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Microchip-Atmel-ATUC256L4U-32-bit-Atmel-AVR-Microcontroller-Manuel
Microchip-Atmel-ATUC256L4U-32-bit-Atmel-AVR-Microcontroller-Manuel
Au format texte :
Features
• High-performance, Low-power 32-bit Atmel® AVR® Microcontroller
– Compact Single-cycle RISC Instruction Set Including DSP Instructions
– Read-modify-write Instructions and Atomic Bit Manipulation
– Performance
• Up to 64DMIPS Running at 50MHz from Flash (1 Flash Wait State)
• Up to 36DMIPS Running at 25MHz from Flash (0 Flash Wait State)
– Memory Protection Unit (MPU)
• Secure Access Unit (SAU) providing User-defined Peripheral Protection
• picoPower® Technology for Ultra-low Power Consumption
• Multi-hierarchy Bus System
– High-performance Data Transfers on Separate Buses for Increased Performance
– 12 Peripheral DMA Channels improve Speed for Peripheral Communication
• Internal High-speed Flash
– 256Kbytes, 128Kbytes, and 64Kbytes Versions
– Single-cycle Access up to 25MHz
– FlashVault Technology Allows Pre-programmed Secure Library Support for End
User Applications
– Prefetch Buffer Optimizing Instruction Execution at Maximum Speed
– 100,000 Write Cycles, 15-year Data Retention Capability
– Flash Security Locks and User-defined Configuration Area
• Internal High-speed SRAM, Single-cycle Access at Full Speed
– 32Kbytes (256Kbytes and 128Kbytes Flash) and 16Kbytes (64Kbytes Flash)
• Interrupt Controller (INTC)
– Autovectored Low-latency Interrupt Service with Programmable Priority
• External Interrupt Controller (EIC)
• Peripheral Event System for Direct Peripheral to Peripheral Communication
• System Functions
– Power and Clock Manager
– SleepWalking Power Saving Control
– Internal System RC Oscillator (RCSYS)
– 32 KHz Oscillator
– Multipurpose Oscillator, Phase Locked Loop (PLL), and Digital Frequency Locked
Loop (DFLL)
• Windowed Watchdog Timer (WDT)
• Asynchronous Timer (AST) with Real-time Clock Capability
– Counter or Calendar Mode Supported
• Frequency Meter (FREQM) for Accurate Measuring of Clock Frequency
• Universal Serial Bus (USBC)
– Full Speed and Low Speed USB Device Support
– Multi-packet Ping-pong Mode
• Six 16-bit Timer/Counter (TC) Channels
– External Clock Inputs, PWM, Capture, and Various Counting Capabilities
• 36 PWM Channels (PWMA)
– 12-bit PWM with a Source Clock up to 150MHz
• Four Universal Synchronous/Asynchronous Receiver/Transmitters (USART)
– Independent Baudrate Generator, Support for SPI
– Support for Hardware Handshaking
32142D–06/2013
32-bit Atmel
AVR
Microcontroller
ATUC256L3U
ATUC128L3U
ATUC64L3U
ATUC256L4U
ATUC128L4U
ATUC64L4U
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32142D–06/2013
ATUC64/128/256L3/4U
• One Master/Slave Serial Peripheral Interface (SPI) with Chip Select Signals
– Up to 15 SPI Slaves can be Addressed
• Two Master and Two Slave Two-wire Interfaces (TWI), 400kbit/s I2
C-compatible
• One 8-channel Analog-to-digital Converter (ADC) with up to 12 Bits Resolution
– Internal Temperature Sensor
• Eight Analog Comparators (AC) with Optional Window Detection
• Capacitive Touch (CAT) Module
– Hardware-assisted Atmel® AVR® QTouch® and Atmel® AVR® QMatrix Touch Acquisition
– Supports QTouch and QMatrix Capture from Capacitive Touch Sensors
• QTouch Library Support
– Capacitive Touch Buttons, Sliders, and Wheels
– QTouch and QMatrix Acquisition
• Audio Bitstream DAC (ABDACB) Suitable for Stereo Audio
• Inter-IC Sound (IISC) Controller
– Compliant with Inter-IC Sound (I2
S) Specification
• On-chip Non-intrusive Debug System
– Nexus Class 2+, Runtime Control, Non-intrusive Data and Program Trace
– aWire Single-pin Programming Trace and Debug Interface, Muxed with Reset Pin
– NanoTrace Provides Trace Capabilities through JTAG or aWire Interface
• 64-pin TQFP/QFN (51 GPIO Pins), 48-pin TQFP/QFN/TLLGA (36 GPIO Pins)
• Six High-drive I/O Pins (64-pin Packages), Four High-drive I/O Pins (48-pin Packages)
• Single 1.62-3.6V Power Supply
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ATUC64/128/256L3/4U
1. Description
The Atmel® AVR® ATUC64/128/256L3/4U is a complete system-on-chip microcontroller based
on the AVR32 UC RISC processor running at frequencies up to 50MHz. AVR32 UC is a highperformance
32-bit RISC microprocessor core, designed for cost-sensitive embedded applications,
with particular emphasis on low power consumption, high code density, and high
performance.
The processor implements a Memory Protection Unit (MPU) and a fast and flexible interrupt controller
for supporting modern and real-time operating systems. The Secure Access Unit (SAU) is
used together with the MPU to provide the required security and integrity.
Higher computation capability is achieved using a rich set of DSP instructions.
The ATUC64/128/256L3/4U embeds state-of-the-art picoPower technology for ultra-low power
consumption. Combined power control techniques are used to bring active current consumption
down to 174µA/MHz, and leakage down to 220nA while still retaining a bank of backup registers.
The device allows a wide range of trade-offs between functionality and power consumption,
giving the user the ability to reach the lowest possible power consumption with the feature set
required for the application.
The Peripheral Direct Memory Access (DMA) controller enables data transfers between peripherals
and memories without processor involvement. The Peripheral DMA controller drastically
reduces processing overhead when transferring continuous and large data streams.
The ATUC64/128/256L3/4U incorporates on-chip Flash and SRAM memories for secure and
fast access. The FlashVault technology allows secure libraries to be programmed into the
device. The secure libraries can be executed while the CPU is in Secure State, but not read by
non-secure software in the device. The device can thus be shipped to end customers, who will
be able to program their own code into the device to access the secure libraries, but without risk
of compromising the proprietary secure code.
The External Interrupt Controller (EIC) allows pins to be configured as external interrupts. Each
external interrupt has its own interrupt request and can be individually masked.
The Peripheral Event System allows peripherals to receive, react to, and send peripheral events
without CPU intervention. Asynchronous interrupts allow advanced peripheral operation in low
power sleep modes.
The Power Manager (PM) improves design flexibility and security. The Power Manager supports
SleepWalking functionality, by which a module can be selectively activated based on peripheral
events, even in sleep modes where the module clock is stopped. Power monitoring is supported
by on-chip Power-on Reset (POR), Brown-out Detector (BOD), and Supply Monitor (SM). The
device features several oscillators, such as Phase Locked Loop (PLL), Digital Frequency
Locked Loop (DFLL), Oscillator 0 (OSC0), and system RC oscillator (RCSYS). Either of these
oscillators can be used as source for the system clock. The DFLL is a programmable internal
oscillator from 20 to 150MHz. It can be tuned to a high accuracy if an accurate reference clock is
running, e.g. the 32KHz crystal oscillator.
The Watchdog Timer (WDT) will reset the device unless it is periodically serviced by the software.
This allows the device to recover from a condition that has caused the system to be
unstable.
The Asynchronous Timer (AST) combined with the 32KHz crystal oscillator supports powerful
real-time clock capabilities, with a maximum timeout of up to 136 years. The AST can operate in
counter or calendar mode.
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ATUC64/128/256L3/4U
The Frequency Meter (FREQM) allows accurate measuring of a clock frequency by comparing it
to a known reference clock.
The Full-speed USB 2.0 device interface (USBC) supports several USB classes at the same
time, thanks to the rich end-point configuration.
The device includes six identical 16-bit Timer/Counter (TC) channels. Each channel can be independently
programmed to perform frequency measurement, event counting, interval
measurement, pulse generation, delay timing, and pulse width modulation.
The Pulse Width Modulation controller (PWMA) provides 12-bit PWM channels which can be
synchronized and controlled from a common timer. 36 PWM channels are available, enabling
applications that require multiple PWM outputs, such as LCD backlight control. The PWM channels
can operate independently, with duty cycles set individually, or in interlinked mode, with
multiple channels changed at the same time.
The ATUC64/128/256L3/4U also features many communication interfaces, like USART, SPI,
and TWI, for communication intensive applications. The USART supports different communication
modes, like SPI Mode and LIN Mode.
A general purpose 8-channel ADC is provided, as well as eight analog comparators (AC). The
ADC can operate in 10-bit mode at full speed or in enhanced mode at reduced speed, offering
up to 12-bit resolution. The ADC also provides an internal temperature sensor input channel.
The analog comparators can be paired to detect when the sensing voltage is within or outside
the defined reference window.
The Capacitive Touch (CAT) module senses touch on external capacitive touch sensors, using
the QTouch technology. Capacitive touch sensors use no external mechanical components,
unlike normal push buttons, and therefore demand less maintenance in the user application.
The CAT module allows up to 17 touch sensors, or up to 16 by 8 matrix sensors to be interfaced.
All touch sensors can be configured to operate autonomously without software interaction,
allowing wakeup from sleep modes when activated.
Atmel offers the QTouch library for embedding capacitive touch buttons, sliders, and wheels
functionality into AVR microcontrollers. The patented charge-transfer signal acquisition offers
robust sensing and includes fully debounced reporting of touch keys as well as Adjacent Key
Suppression® (AKS®) technology for unambiguous detection of key events. The easy-to-use
QTouch Suite toolchain allows you to explore, develop, and debug your own touch applications.
The Audio Bitstream DAC (ABDACB) converts a 16-bit sample value to a digital bitstream with
an average value proportional to the sample value. Two channels are supported, making the
ABDAC particularly suitable for stereo audio.
The Inter-IC Sound Controller (IISC) provides a 5-bit wide, bidirectional, synchronous, digital
audio link with external audio devices. The controller is compliant with the Inter-IC Sound (I2S)
bus specification.
The ATUC64/128/256L3/4U integrates a class 2+ Nexus 2.0 On-chip Debug (OCD) System,
with non-intrusive real-time trace and full-speed read/write memory access, in addition to basic
runtime control. The NanoTrace interface enables trace feature for aWire- or JTAG-based
debuggers. The single-pin aWire interface allows all features available through the JTAG interface
to be accessed through the RESET pin, allowing the JTAG pins to be used for GPIO or
peripherals.
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32142D–06/2013
ATUC64/128/256L3/4U
2. Overview
2.1 Block Diagram
Figure 2-1. Block Diagram
INTERRUPT
CONTROLLER
ASYNCHRONOUS
TIMER
PERIPHERAL
DMA
CONTROLLER
HSB-PB
BRIDGE B
HSB-PB
BRIDGE A
S
MM M
S
S
M
EXTERNAL INTERRUPT
CONTROLLER
HIGH SPEED
BUS MATRIX
GENERALPURPOSE I/Os
GENERAL PURPOSE I/Os
PA
PB
EXTINT[5..1]
NMI
PA
PB
SPI
DMA
MISO, MOSI
NPCS[3..0]
USART0
USART1
USART2
USART3
DMA
RXD
TXD
CLK
RTS, CTS
WATCHDOG
TIMER
SCK
JTAG
INTERFACE
MCKO
MDO[5..0]
MSEO[1..0]
EVTI_N
TDO
TDI
TMS
CONFIGURATION REGISTERS BUS
256/128/64
KB S FLASH
FLASH
CONTROLLER
EVTO_N
AVR32UC CPU
NEXUS
CLASS 2+
OCD
INSTR
INTERFACE
DATA
INTERFACE
MEMORY INTERFACE
LOCAL BUS
32/16 KB
SRAM
MEMORY PROTECTION UNIT
LOCAL BUS
INTERFACE
FREQUENCY METER
PWMA[35..0] PWM CONTROLLER
TWI MASTER 0
DMA
TWI MASTER 1
TWI SLAVE 0
DMA
TWI SLAVE 1
8-CHANNEL ADC
DMA
INTERFACE
POWER MANAGER
RESET
CONTROLLER
SLEEP
CONTROLLER
CLOCK
CONTROLLER
TCK
RESET_N aWire
CAPACITIVE TOUCH
DMA
MODULE
AC INTERFACE
ACREFN
ACAN[3..0]
ACBN[3..0]
ACBP[3..0]
ACAP[3..0]
TWCK
TWD
TWALM
TWCK
TWD
TWALM
GLUE LOGIC
CONTROLLER IN[7..0]
OUT[1..0]
USB 2.0
Interface 8EP
DMA
INTER-IC SOUND
CONTROLLER
TIMER/COUNTER 0
TIMER/COUNTER 1
A[2..0]
B[2..0]
AUDIO BITSTREAM
DMA
DAC DAC0, DAC1
DACN0, DACN1
ISCK
IWS
ISDI
ISDO
IMCK
CLK
SAU S/M
S
DM
DP
SYSTEM CONTROL
INTERFACE
GCLK[9..0]
XIN32
XOUT32 OSC32K
RCSYS
XIN0
XOUT0 OSC0
DFLL
RC32K
RC120M
RC32OUT
PLL
GCLK_IN[2..0]
CSB[16:0]
SMP
CSA[16:0]
SYNC
VDIVEN
DIS
TRIGGER
ADP[1..0]
AD[8..0]
DATAOUT
ADVREFP
CLK[2..0]
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32142D–06/2013
ATUC64/128/256L3/4U
2.2 Configuration Summary
Table 2-1. Configuration Summary
Feature ATUC256L3U ATUC128L3U ATUC64L3U ATUC256L4U ATUC128L4U ATUC64L4U
Flash 256KB 128KB 64KB 256KB 128KB 64KB
SRAM 32KB 16KB 32KB 16KB
GPIO 51 36
High-drive pins 6 4
External Interrupts 6
TWI 2
USART 4
Peripheral DMA Channels 12
Peripheral Event System 1
SPI 1
Asynchronous Timers 1
Timer/Counter Channels 6
PWM channels 36
Frequency Meter 1
Watchdog Timer 1
Power Manager 1
Secure Access Unit 1
Glue Logic Controller 1
Oscillators
Digital Frequency Locked Loop 20-150MHz (DFLL)
Phase Locked Loop 40-240MHz (PLL)
Crystal Oscillator 0.45-16MHz (OSC0)
Crystal Oscillator 32KHz (OSC32K)
RC Oscillator 120MHz (RC120M)
RC Oscillator 115kHz (RCSYS)
RC Oscillator 32kHz (RC32K)
ADC 8-channel 12-bit
Temperature Sensor 1
Analog Comparators 8
Capacitive Touch Module 1
JTAG 1
aWire 1
USB 1
Audio Bitstream DAC 1 0
IIS Controller 1 0
Max Frequency 50MHz
Packages TQFP64/QFN64 TQFP48/QFN48/TLLGA48
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32142D–06/2013
ATUC64/128/256L3/4U
3. Package and Pinout
3.1 Package
The device pins are multiplexed with peripheral functions as described in Section .
Figure 3-1. ATUC64/128/256L4U TQFP48/QFN48 Pinout GND 1 PA09
2
PA08
3
PA03
4
PB12
5
PB00
6
PB02
7
PB03
8
PA22
9
PA06 10
PA00 11
PA05 12
13 PA02
14 PA01
15 PB13
16 PB14
17 VDDIN
18 VDDCORE
19 GND
20 PB05
21 PB04
22 RESET_N
23 PB10
24 PA21
PA14 36
VDDANA 35
ADVREFP 34
GNDANA 33
PB08 32
PB07 31
PB06 30
PB09 29
PA04 28
PA11 27
PA13 26
PA20 25
PA15 37
PA16 38
PA17 39
PA19 40
PA18 41
VDDIO 42
GND 43
PB11 44
GND 45
PA10 46
PA12 47
VDDIO 48
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32142D–06/2013
ATUC64/128/256L3/4U
Figure 3-2. ATUC64/128/256L4U TLLGA48 Pinout GND 1 PA09
2
PA08
3
PA03
4
PB12
5
PB00
6
PB02
7
PB03
8
PA22
9
PA06 10
PA00 11
PA05 12
PA02 13
14 PA01
15 PB13
16 PB14
17 VDDIN
18 VDDCORE
19 GND
20 PB05
21 PB04
22 RESET_N
23 PB10
24 PA21
PA14 36
VDDANA 35
ADVREFP 34
GNDANA 33
PB08 32
PB07 31
PB06 30
PB09 29
PA04 28
PA11 27
PA13 26
PA20 25
PA15 37
PA16 38
PA17 39
PA19 40
PA18 41
VDDIO 42
GND 43
PB11 44
GND 45
PA10 46
PA12 47
VDDIO 48
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32142D–06/2013
ATUC64/128/256L3/4U
Figure 3-3. ATUC64/128/256L3U TQFP64/QFN64 Pinout GND 1 PA09
2
PA08
3
PB19
4
PB20
5
PA03
6
PB12
7
PB00
8
PB02
9
PB03 10
VDDIO 11
GND 12
PA22 13
PA06 14
PA00 15
PA05 16
17 PA02
18 PA01
19 PA07
20 PB01
21 PB26
22 PB13
23 PB14
24 PB27
PB08 44
PB07 43
PB06 42
PB22 41
PB21 40
PB09 39
PA04 38
VDDIO 37
GND 36
PA11 35
PA13 34
PA20 33
PA15 49
PA16 50
PA17 51
PA19 52
PA18 53
PB23 54
PB24 55
PB11 56
PB15 57
PB16 58
PB17 59
PB18 60
25 VDDIN
26
27 GND
28 PB05
29 PB04
30
31 PB10
32 PA21
PA14 48
VDDANA 47
ADVREFP 46
GNDANA 45
PB25 61
PA10 62
PA12 63
VDDIO 64
VDDCORE
RESET_N
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32142D–06/2013
ATUC64/128/256L3/4U
Peripheral Multiplexing on I/O lines
3.1.1 Multiplexed Signals
Each GPIO line can be assigned to one of the peripheral functions. The following table
describes the peripheral signals multiplexed to the GPIO lines.
Table 3-1. GPIO Controller Function Multiplexing
48-
pin
64-
pin
Pin
Name
G
PI
O Supply
Pad
Type
GPIO Function
ABCDE F GH
11 15 PA00 0 VDDIO Normal
I/O
USART0-
TXD
USART1-
RTS
SPINPCS[2]
PWMAPWMA[0]
SCIFGCLK[0]
CATCSA[2]
14 18 PA01 1 VDDIO Normal
I/O
USART0-
RXD
USART1-
CTS
SPINPCS[3]
USART1-
CLK
PWMAPWMA[1]
ACIFBACAP[0]
TWIMS0-
TWALM
CATCSA[1]
13 17 PA02 2 VDDIO Highdrive
I/O
USART0-
RTS
ADCIFBTRIGGER
USART2-
TXD TC0-A0 PWMAPWMA[2]
ACIFBACBP[0]
USART0-
CLK
CATCSA[3]
4 6 PA03 3 VDDIO Normal
I/O
USART0-
CTS
SPINPCS[1]
USART2-
TXD TC0-B0 PWMAPWMA[3]
ACIFBACBN[3]
USART0-
CLK
CATCSB[3]
28 38 PA04 4 VDDIO Normal
I/O SPI-MISO TWIMS0-
TWCK
USART1-
RXD TC0-B1 PWMAPWMA[4]
ACIFBACBP[1]
CATCSA[7]
12 16 PA05 5 VDDIO Normal
I/O (TWI) SPI-MOSI TWIMS1-
TWCK
USART1-
TXD TC0-A1 PWMAPWMA[5]
ACIFBACBN[0]
TWIMS0-
TWD
CATCSB[7]
10 14 PA06 6 VDDIO
Highdrive
I/O,
5V
tolerant
SPI-SCK USART2-
TXD
USART1-
CLK TC0-B0 PWMAPWMA[6]
EICEXTINT[2]
SCIFGCLK[1]
CATCSB[1]
19 PA07 7 VDDIO Normal
I/O (TWI)
SPINPCS[0]
USART2-
RXD
TWIMS1-
TWALM
TWIMS0-
TWCK
PWMAPWMA[7]
ACIFBACAN[0]
EICNMI
(EXTINT[0])
CATCSB[2]
3 3 PA08 8 VDDIO Highdrive
I/O
USART1-
TXD
SPINPCS[2]
TC0-A2 ADCIFBADP[0]
PWMAPWMA[8]
CATCSA[4]
2 2 PA09 9 VDDIO Highdrive
I/O
USART1-
RXD
SPINPCS[3]
TC0-B2 ADCIFBADP[1]
PWMAPWMA[9]
SCIFGCLK[2]
EICEXTINT[1]
CATCSB[4]
46 62 PA10 10 VDDIO Normal
I/O
TWIMS0-
TWD TC0-A0 PWMAPWMA[10]
ACIFBACAP[1]
SCIFGCLK[2]
CATCSA[5]
27 35 PA11 11 VDDIN Normal
I/O
PWMAPWMA[11]
47 63 PA12 12 VDDIO Normal
I/O
USART2-
CLK TC0-CLK1 CAT-SMP PWMAPWMA[12]
ACIFBACAN[1]
SCIFGCLK[3]
CATCSB[5]
26 34 PA13 13 VDDIN Normal
I/O
GLOCOUT[0]
GLOCIN[7]
TC0-A0 SCIFGCLK[2]
PWMAPWMA[13]
CAT-SMP EICEXTINT[2]
CATCSA[0]
36 48 PA14 14 VDDIO Normal
I/O
ADCIFBAD[0]
TC0-CLK2 USART2-
RTS CAT-SMP PWMAPWMA[14]
SCIFGCLK[4]
CATCSA[6]
37 49 PA15 15 VDDIO Normal
I/O
ADCIFBAD[1]
TC0-CLK1 GLOCIN[6]
PWMAPWMA[15]
CATSYNC
EICEXTINT[3]
CATCSB[6]
38 50 PA16 16 VDDIO Normal
I/O
ADCIFBAD[2]
TC0-CLK0 GLOCIN[5]
PWMAPWMA[16]
ACIFBACREFN
EICEXTINT[4]
CATCSA[8]
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39 51 PA17 17 VDDIO Normal
I/O (TWI) TC0-A1 USART2-
CTS
TWIMS1-
TWD
PWMAPWMA[17]
CAT-SMP CAT-DIS CATCSB[8]
41 53 PA18 18 VDDIO Normal
I/O
ADCIFBAD[4]
TC0-B1 GLOCIN[4]
PWMAPWMA[18]
CATSYNC
EICEXTINT[5]
CATCSB[0]
40 52 PA19 19 VDDIO Normal
I/O
ADCIFBAD[5]
TC0-A2 TWIMS1-
TWALM
PWMAPWMA[19]
SCIFGCLK_IN[
0]
CAT-SYNC CATCSA[10]
25 33 PA20 20 VDDIN Normal
I/O
USART2-
TXD TC0-A1 GLOCIN[3]
PWMAPWMA[20]
SCIFRC32OUT
CATCSA[12]
24 32 PA21 21 VDDIN
Normal
I/O (TWI,
5V
tolerant,
SMBus)
USART2-
RXD
TWIMS0-
TWD TC0-B1 ADCIFBTRIGGER
PWMAPWMA[21]
PWMAPWMAOD
[21]
SCIFGCLK[0]
CATSMP
9 13 PA22 22 VDDIO Normal
I/O
USART0-
CTS
USART2-
CLK TC0-B2 CAT-SMP PWMAPWMA[22]
ACIFBACBN[2]
CATCSB[10]
6 8 PB00 32 VDDIO Normal
I/O
USART3-
TXD
ADCIFBADP[0]
SPINPCS[0]
TC0-A1 PWMAPWMA[23]
ACIFBACAP[2]
TC1-A0 CATCSA[9]
20 PB01 33 VDDIO Highdrive
I/O
USART3-
RXD
ADCIFBADP[1]
SPI-SCK TC0-B1 PWMAPWMA[24]
TC1-A1 CATCSB[9]
7 9 PB02 34 VDDIO Normal
I/O
USART3-
RTS
USART3-
CLK SPI-MISO TC0-A2 PWMAPWMA[25]
ACIFBACAN[2]
SCIFGCLK[1]
CATCSB[11]
8 10 PB03 35 VDDIO Normal
I/O
USART3-
CTS
USART3-
CLK SPI-MOSI TC0-B2 PWMAPWMA[26]
ACIFBACBP[2]
TC1-A2 CATCSA[11]
21 29 PB04 36 VDDIN
Normal
I/O (TWI,
5V
tolerant,
SMBus)
TC1-A0 USART1-
RTS
USART1-
CLK
TWIMS0-
TWALM
PWMAPWMA[27]
PWMAPWMAOD
[27]
TWIMS1-
TWCK
CATCSA[14]
20 28 PB05 37 VDDIN
Normal
I/O (TWI,
5V
tolerant,
SMBus)
TC1-B0 USART1-
CTS
USART1-
CLK
TWIMS0-
TWCK
PWMAPWMA[28]
PWMAPWMAOD
[28]
SCIFGCLK[3]
CATCSB[14]
30 42 PB06 38 VDDIO Normal
I/O TC1-A1 USART3-
TXD
ADCIFBAD[6]
GLOCIN[2]
PWMAPWMA[29]
ACIFBACAN[3]
EICNMI
(EXTINT[0])
CATCSB[13]
31 43 PB07 39 VDDIO Normal
I/O TC1-B1 USART3-
RXD
ADCIFBAD[7]
GLOCIN[1]
PWMAPWMA[30]
ACIFBACAP[3]
EICEXTINT[1]
CATCSA[13]
32 44 PB08 40 VDDIO Normal
I/O TC1-A2 USART3-
RTS
ADCIFBAD[8]
GLOCIN[0]
PWMAPWMA[31]
CATSYNC
EICEXTINT[2]
CATCSB[12]
29 39 PB09 41 VDDIO Normal
I/O TC1-B2 USART3-
CTS
USART3-
CLK
PWMAPWMA[32]
ACIFBACBN[1]
EICEXTINT[3]
CATCSB[15]
23 31 PB10 42 VDDIN Normal
I/O TC1-CLK0 USART1-
TXD
USART3-
CLK
GLOCOUT[1]
PWMAPWMA[33]
SCIFGCLK_IN[
1]
EICEXTINT[4]
CATCSB[16]
44 56 PB11 43 VDDIO Normal
I/O TC1-CLK1 USART1-
RXD
ADCIFBTRIGGER
PWMAPWMA[34]
CATVDIVEN
EICEXTINT[5]
CATCSA[16]
5 7 PB12 44 VDDIO Normal
I/O TC1-CLK2 TWIMS1-
TWALM
CATSYNC
PWMAPWMA[35]
ACIFBACBP[3]
SCIFGCLK[4]
CATCSA[15]
15 22 PB13 45 VDDIN USB I/O USBC-DM USART3-
TXD TC1-A1 PWMAPWMA[7]
ADCIFBADP[1]
SCIFGCLK[5]
CATCSB[2]
16 23 PB14 46 VDDIN USB I/O USBC-DP USART3-
RXD TC1-B1 PWMAPWMA[24]
SCIFGCLK[5]
CATCSB[9]
Table 3-1. GPIO Controller Function Multiplexing
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3.2 See Section 3.3 for a description of the various peripheral signals.
Refer to ”Electrical Characteristics” on page 897 for a description of the electrical properties of
the pin types used.
3.2.1 TWI, 5V Tolerant, and SMBUS Pins
Some normal I/O pins offer TWI, 5V tolerance, and SMBUS features. These features are only
available when either of the TWI functions or the PWMAOD function in the PWMA are selected
for these pins.
Refer to the ”Electrical Characteristics” on page 897 for a description of the electrical properties
of the TWI, 5V tolerance, and SMBUS pins.
57 PB15 47 VDDIO Highdrive
I/O
ABDACBCLK
IISCIMCK
SPI-SCK TC0-CLK2 PWMAPWMA[8]
SCIFGCLK[3]
CATCSB[4]
58 PB16 48 VDDIO Normal
I/O
ABDACBDAC[0]
IISC-ISCK USART0-
TXD
PWMAPWMA[9]
SCIFGCLK[2]
CATCSA[5]
59 PB17 49 VDDIO Normal
I/O
ABDACBDAC[1]
IISC-IWS USART0-
RXD
PWMAPWMA[10]
CATCSB[5]
60 PB18 50 VDDIO Normal
I/O
ABDACBDACN[0]
IISC-ISDI USART0-
RTS
PWMAPWMA[12]
CATCSA[0]
4 PB19 51 VDDIO Normal
I/O
ABDACBDACN[1]
IISC-ISDO USART0-
CTS
PWMAPWMA[20]
EICEXTINT[1]
CATCSA[12]
5 PB20 52 VDDIO Normal
I/O
TWIMS1-
TWD
USART2-
RXD
SPINPCS[1]
TC0-A0 PWMAPWMA[21]
USART1-
RTS
USART1-
CLK
CATCSA[14]
40 PB21 53 VDDIO Normal
I/O
TWIMS1-
TWCK
USART2-
TXD
SPINPCS[2]
TC0-B0 PWMAPWMA[28]
USART1-
CTS
USART1-
CLK
CATCSB[14]
41 PB22 54 VDDIO Normal
I/O
TWIMS1-
TWALM
SPINPCS[3]
TC0-CLK0 PWMAPWMA[27]
ADCIFBTRIGGER
SCIFGCLK[0]
CATCSA[8]
54 PB23 55 VDDIO Normal
I/O SPI-MISO USART2-
RTS
USART2-
CLK TC0-A2 PWMAPWMA[0]
CAT-SMP SCIFGCLK[6]
CATCSA[4]
55 PB24 56 VDDIO Normal
I/O SPI-MOSI USART2-
CTS
USART2-
CLK TC0-B2 PWMAPWMA[1]
ADCIFBADP[1]
SCIFGCLK[7]
CATCSA[2]
61 PB25 57 VDDIO Normal
I/O
SPINPCS[0]
USART1-
RXD TC0-A1 PWMAPWMA[2]
SCIFGCLK_IN[
2]
SCIFGCLK[8]
CATCSA[3]
21 PB26 58 VDDIO Normal
I/O SPI-SCK USART1-
TXD TC0-B1 PWMAPWMA[3]
ADCIFBADP[0]
SCIFGCLK[9]
CATCSB[3]
24 PB27 59 VDDIN Normal
I/O
USART1-
RXD TC0-CLK1 PWMAPWMA[4]
ADCIFBADP[1]
EICNMI
(EXTINT[0])
CATCSA[9]
Table 3-1. GPIO Controller Function Multiplexing
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3.2.2 Peripheral Functions
Each GPIO line can be assigned to one of several peripheral functions. The following table
describes how the various peripheral functions are selected. The last listed function has priority
in case multiple functions are enabled on the same pin.
3.2.3 JTAG Port Connections
If the JTAG is enabled, the JTAG will take control over a number of pins, irrespectively of the I/O
Controller configuration.
3.2.4 Nexus OCD AUX Port Connections
If the OCD trace system is enabled, the trace system will take control over a number of pins, irrespectively
of the I/O Controller configuration. Two different OCD trace pin mappings are
possible, depending on the configuration of the OCD AXS register. For details, see the AVR32
UC Technical Reference Manual.
Table 3-2. Peripheral Functions
Function Description
GPIO Controller Function multiplexing GPIO and GPIO peripheral selection A to H
Nexus OCD AUX port connections OCD trace system
aWire DATAOUT aWire output in two-pin mode
JTAG port connections JTAG debug port
Oscillators OSC0, OSC32
Table 3-3. JTAG Pinout
48-pin 64-pin Pin name JTAG pin
11 15 PA00 TCK
14 18 PA01 TMS
13 17 PA02 TDO
4 6 PA03 TDI
Table 3-4. Nexus OCD AUX Port Connections
Pin AXS=1 AXS=0
EVTI_N PA05 PB08
MDO[5] PA10 PB00
MDO[4] PA18 PB04
MDO[3] PA17 PB05
MDO[2] PA16 PB03
MDO[1] PA15 PB02
MDO[0] PA14 PB09
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3.2.5 Oscillator Pinout
The oscillators are not mapped to the normal GPIO functions and their muxings are controlled
by registers in the System Control Interface (SCIF). Please refer to the SCIF chapter for more
information about this.
3.2.6 Other Functions
The functions listed in Table 3-6 are not mapped to the normal GPIO functions. The aWire DATA
pin will only be active after the aWire is enabled. The aWire DATAOUT pin will only be active
after the aWire is enabled and the 2_PIN_MODE command has been sent. The WAKE_N pin is
always enabled. Please refer to Section 6.1.4.2 on page 44 for constraints on the WAKE_N pin.
EVTO_N PA04 PA04
MCKO PA06 PB01
MSEO[1] PA07 PB11
MSEO[0] PA11 PB12
Table 3-4. Nexus OCD AUX Port Connections
Pin AXS=1 AXS=0
Table 3-5. Oscillator Pinout
48-pin 64-pin Pin Name Oscillator Pin
3 3 PA08 XIN0
46 62 PA10 XIN32
26 34 PA13 XIN32_2
2 2 PA09 XOUT0
47 63 PA12 XOUT32
25 33 PA20 XOUT32_2
Table 3-6. Other Functions
48-pin 64-pin Pin Name Function
27 35 PA11 WAKE_N
22 30 RESET_N aWire DATA
11 15 PA00 aWire DATAOUT
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3.3 Signal Descriptions
The following table gives details on signal name classified by peripheral.
Table 3-7. Signal Descriptions List
Signal Name Function Type
Active
Level Comments
Audio Bitstream DAC - ABDACB
CLK D/A Clock out Output
DAC1 - DAC0 D/A Bitstream out Output
DACN1 - DACN0 D/A Inverted bitstream out Output
Analog Comparator Interface - ACIFB
ACAN3 - ACAN0 Negative inputs for comparators "A" Analog
ACAP3 - ACAP0 Positive inputs for comparators "A" Analog
ACBN3 - ACBN0 Negative inputs for comparators "B" Analog
ACBP3 - ACBP0 Positive inputs for comparators "B" Analog
ACREFN Common negative reference Analog
ADC Interface - ADCIFB
AD8 - AD0 Analog Signal Analog
ADP1 - ADP0 Drive Pin for resistive touch screen Output
TRIGGER External trigger Input
aWire - AW
DATA aWire data I/O
DATAOUT aWire data output for 2-pin mode I/O
Capacitive Touch Module - CAT
CSA16 - CSA0 Capacitive Sense A I/O
CSB16 - CSB0 Capacitive Sense B I/O
DIS Discharge current control Analog
SMP SMP signal Output
SYNC Synchronize signal Input
VDIVEN Voltage divider enable Output
External Interrupt Controller - EIC
NMI (EXTINT0) Non-Maskable Interrupt Input
EXTINT5 - EXTINT1 External interrupt Input
Glue Logic Controller - GLOC
IN7 - IN0 Inputs to lookup tables Input
OUT1 - OUT0 Outputs from lookup tables Output
Inter-IC Sound (I2S) Controller - IISC
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IMCK I2S Master Clock Output
ISCK I2S Serial Clock I/O
ISDI I2S Serial Data In Input
ISDO I2S Serial Data Out Output
IWS I2S Word Select I/O
JTAG module - JTAG
TCK Test Clock Input
TDI Test Data In Input
TDO Test Data Out Output
TMS Test Mode Select Input
Power Manager - PM
RESET_N Reset Input Low
Pulse Width Modulation Controller - PWMA
PWMA35 - PWMA0 PWMA channel waveforms Output
PWMAOD35 -
PWMAOD0
PWMA channel waveforms, open drain
mode Output Not all channels support open
drain mode
System Control Interface - SCIF
GCLK9 - GCLK0 Generic Clock Output Output
GCLK_IN2 - GCLK_IN0 Generic Clock Input Input
RC32OUT RC32K output at startup Output
XIN0 Crystal 0 Input Analog/
Digital
XIN32 Crystal 32 Input (primary location) Analog/
Digital
XIN32_2 Crystal 32 Input (secondary location) Analog/
Digital
XOUT0 Crystal 0 Output Analog
XOUT32 Crystal 32 Output (primary location) Analog
XOUT32_2 Crystal 32 Output (secondary location) Analog
Serial Peripheral Interface - SPI
MISO Master In Slave Out I/O
MOSI Master Out Slave In I/O
NPCS3 - NPCS0 SPI Peripheral Chip Select I/O Low
SCK Clock I/O
Timer/Counter - TC0, TC1
A0 Channel 0 Line A I/O
A1 Channel 1 Line A I/O
A2 Channel 2 Line A I/O
Table 3-7. Signal Descriptions List
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Note: 1. ADCIFB: AD3 does not exist.
B0 Channel 0 Line B I/O
B1 Channel 1 Line B I/O
B2 Channel 2 Line B I/O
CLK0 Channel 0 External Clock Input Input
CLK1 Channel 1 External Clock Input Input
CLK2 Channel 2 External Clock Input Input
Two-wire Interface - TWIMS0, TWIMS1
TWALM SMBus SMBALERT I/O Low
TWCK Two-wire Serial Clock I/O
TWD Two-wire Serial Data I/O
Universal Synchronous Asynchronous Receiver Transmitter - USART0, USART1, USART2, USART3
CLK Clock I/O
CTS Clear To Send Input Low
RTS Request To Send Output Low
RXD Receive Data Input
TXD Transmit Data Output
Table 3-7. Signal Descriptions List
Table 3-8. Signal Description List, Continued
Signal Name Function Type
Active
Level Comments
Power
VDDCORE Core Power Supply / Voltage Regulator Output Power
Input/Output 1.62V to 1.98V
VDDIO I/O Power Supply Power Input
1.62V to 3.6V. VDDIO should
always be equal to or lower than
VDDIN.
VDDANA Analog Power Supply Power Input 1.62V to 1.98V
ADVREFP Analog Reference Voltage Power Input 1.62V to 1.98V
VDDIN Voltage Regulator Input Power Input 1.62V to 3.6V(1)
GNDANA Analog Ground Ground
GND Ground Ground
Auxiliary Port - AUX
MCKO Trace Data Output Clock Output
MDO5 - MDO0 Trace Data Output Output
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Note: 1. See Section 6. on page 39
3.4 I/O Line Considerations
3.4.1 JTAG Pins
The JTAG is enabled if TCK is low while the RESET_N pin is released. The TCK, TMS, and TDI
pins have pull-up resistors when JTAG is enabled. The TCK pin always has pull-up enabled during
reset. The TDO pin is an output, driven at VDDIO, and has no pull-up resistor. The JTAG
pins can be used as GPIO pins and multiplexed with peripherals when the JTAG is disabled.
Please refer to Section 3.2.3 on page 13 for the JTAG port connections.
3.4.2 PA00
Note that PA00 is multiplexed with TCK. PA00 GPIO function must only be used as output in the
application.
3.4.3 RESET_N Pin
The RESET_N pin is a schmitt input and integrates a permanent pull-up resistor to VDDIN. As
the product integrates a power-on reset detector, the RESET_N pin can be left unconnected in
case no reset from the system needs to be applied to the product.
The RESET_N pin is also used for the aWire debug protocol. When the pin is used for debugging,
it must not be driven by external circuitry.
3.4.4 TWI Pins PA21/PB04/PB05
When these pins are used for TWI, the pins are open-drain outputs with slew-rate limitation and
inputs with spike filtering. When used as GPIO pins or used for other peripherals, the pins have
the same characteristics as other GPIO pins. Selected pins are also SMBus compliant (refer to
Section on page 10). As required by the SMBus specification, these pins provide no leakage
path to ground when the ATUC64/128/256L3/4U is powered down. This allows other devices on
the SMBus to continue communicating even though the ATUC64/128/256L3/4U is not powered.
After reset a TWI function is selected on these pins instead of the GPIO. Please refer to the
GPIO Module Configuration chapter for details.
MSEO1 - MSEO0 Trace Frame Control Output
EVTI_N Event In Input Low
EVTO_N Event Out Output Low
General Purpose I/O pin
PA22 - PA00 Parallel I/O Controller I/O Port 0 I/O
PB27 - PB00 Parallel I/O Controller I/O Port 1 I/O
Table 3-8. Signal Description List, Continued
Signal Name Function Type
Active
Level Comments
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3.4.5 TWI Pins PA05/PA07/PA17
When these pins are used for TWI, the pins are open-drain outputs with slew-rate limitation and
inputs with spike filtering. When used as GPIO pins or used for other peripherals, the pins have
the same characteristics as other GPIO pins.
After reset a TWI function is selected on these pins instead of the GPIO. Please refer to the
GPIO Module Configuration chapter for details.
3.4.6 GPIO Pins
All the I/O lines integrate a pull-up resistor Programming of this pull-up resistor is performed
independently for each I/O line through the GPIO Controllers. After reset, I/O lines default as
inputs with pull-up resistors disabled, except PA00 which has the pull-up resistor enabled. PA20
selects SCIF-RC32OUT (GPIO Function F) as default enabled after reset.
3.4.7 High-drive Pins
The six pins PA02, PA06, PA08, PA09, PB01, and PB15 have high-drive output capabilities.
Refer to Section 35. on page 897 for electrical characteristics.
3.4.8 USB Pins PB13/PB14
When these pins are used for USB, the pins are behaving according to the USB specification.
When used as GPIO pins or used for other peripherals, the pins have the same behaviour as
other normal I/O pins, but the characteristics are different. Refer to Section 35. on page 897 for
electrical characteristics.
To be able to use the USB I/O the VDDIN power supply must be 3.3V nominal.
3.4.9 RC32OUT Pin
3.4.9.1 Clock output at startup
After power-up, the clock generated by the 32kHz RC oscillator (RC32K) will be output on PA20,
even when the device is still reset by the Power-On Reset Circuitry. This clock can be used by
the system to start other devices or to clock a switching regulator to rise the power supply voltage
up to an acceptable value.
The clock will be available on PA20, but will be disabled if one of the following conditions are
true:
• PA20 is configured to use a GPIO function other than F (SCIF-RC32OUT)
• PA20 is configured as a General Purpose Input/Output (GPIO)
• The bit FRC32 in the Power Manager PPCR register is written to zero (refer to the Power
Manager chapter)
The maximum amplitude of the clock signal will be defined by VDDIN.
Once the RC32K output on PA20 is disabled it can never be enabled again.
3.4.9.2 XOUT32_2 function
PA20 selects RC32OUT as default enabled after reset. This function is not automatically disabled
when the user enables the XOUT32_2 function on PA20. This disturbs the oscillator and
may result in the wrong frequency. To avoid this, RC32OUT must be disabled when XOUT32_2
is enabled.
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3.4.10 ADC Input Pins
These pins are regular I/O pins powered from the VDDIO. However, when these pins are used
for ADC inputs, the voltage applied to the pin must not exceed 1.98V. Internal circuitry ensures
that the pin cannot be used as an analog input pin when the I/O drives to VDD. When the pins
are not used for ADC inputs, the pins may be driven to the full I/O voltage range.
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4. Processor and Architecture
Rev: 2.1.2.0
This chapter gives an overview of the AVR32UC CPU. AVR32UC is an implementation of the
AVR32 architecture. A summary of the programming model, instruction set, and MPU is presented.
For further details, see the AVR32 Architecture Manual and the AVR32UC Technical
Reference Manual.
4.1 Features
• 32-bit load/store AVR32A RISC architecture
– 15 general-purpose 32-bit registers
– 32-bit Stack Pointer, Program Counter and Link Register reside in register file
– Fully orthogonal instruction set
– Privileged and unprivileged modes enabling efficient and secure operating systems
– Innovative instruction set together with variable instruction length ensuring industry leading
code density
– DSP extension with saturating arithmetic, and a wide variety of multiply instructions
• 3-stage pipeline allowing one instruction per clock cycle for most instructions
– Byte, halfword, word, and double word memory access
– Multiple interrupt priority levels
• MPU allows for operating systems with memory protection
• Secure State for supporting FlashVault technology
4.2 AVR32 Architecture
AVR32 is a new, high-performance 32-bit RISC microprocessor architecture, designed for costsensitive
embedded applications, with particular emphasis on low power consumption and high
code density. In addition, the instruction set architecture has been tuned to allow a variety of
microarchitectures, enabling the AVR32 to be implemented as low-, mid-, or high-performance
processors. AVR32 extends the AVR family into the world of 32- and 64-bit applications.
Through a quantitative approach, a large set of industry recognized benchmarks has been compiled
and analyzed to achieve the best code density in its class. In addition to lowering the
memory requirements, a compact code size also contributes to the core’s low power characteristics.
The processor supports byte and halfword data types without penalty in code size and
performance.
Memory load and store operations are provided for byte, halfword, word, and double word data
with automatic sign- or zero extension of halfword and byte data. The C-compiler is closely
linked to the architecture and is able to exploit code optimization features, both for size and
speed.
In order to reduce code size to a minimum, some instructions have multiple addressing modes.
As an example, instructions with immediates often have a compact format with a smaller immediate,
and an extended format with a larger immediate. In this way, the compiler is able to use
the format giving the smallest code size.
Another feature of the instruction set is that frequently used instructions, like add, have a compact
format with two operands as well as an extended format with three operands. The larger
format increases performance, allowing an addition and a data move in the same instruction in a
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single cycle. Load and store instructions have several different formats in order to reduce code
size and speed up execution.
The register file is organized as sixteen 32-bit registers and includes the Program Counter, the
Link Register, and the Stack Pointer. In addition, register R12 is designed to hold return values
from function calls and is used implicitly by some instructions.
4.3 The AVR32UC CPU
The AVR32UC CPU targets low- and medium-performance applications, and provides an
advanced On-Chip Debug (OCD) system, no caches, and a Memory Protection Unit (MPU).
Java acceleration hardware is not implemented.
AVR32UC provides three memory interfaces, one High Speed Bus master for instruction fetch,
one High Speed Bus master for data access, and one High Speed Bus slave interface allowing
other bus masters to access data RAMs internal to the CPU. Keeping data RAMs internal to the
CPU allows fast access to the RAMs, reduces latency, and guarantees deterministic timing.
Also, power consumption is reduced by not needing a full High Speed Bus access for memory
accesses. A dedicated data RAM interface is provided for communicating with the internal data
RAMs.
A local bus interface is provided for connecting the CPU to device-specific high-speed systems,
such as floating-point units and I/O controller ports. This local bus has to be enabled by writing a
one to the LOCEN bit in the CPUCR system register. The local bus is able to transfer data
between the CPU and the local bus slave in a single clock cycle. The local bus has a dedicated
memory range allocated to it, and data transfers are performed using regular load and store
instructions. Details on which devices that are mapped into the local bus space is given in the
CPU Local Bus section in the Memories chapter.
Figure 4-1 on page 23 displays the contents of AVR32UC.
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Figure 4-1. Overview of the AVR32UC CPU
4.3.1 Pipeline Overview
AVR32UC has three pipeline stages, Instruction Fetch (IF), Instruction Decode (ID), and Instruction
Execute (EX). The EX stage is split into three parallel subsections, one arithmetic/logic
(ALU) section, one multiply (MUL) section, and one load/store (LS) section.
Instructions are issued and complete in order. Certain operations require several clock cycles to
complete, and in this case, the instruction resides in the ID and EX stages for the required number
of clock cycles. Since there is only three pipeline stages, no internal data forwarding is
required, and no data dependencies can arise in the pipeline.
Figure 4-2 on page 24 shows an overview of the AVR32UC pipeline stages.
AVR32UC CPU pipeline
Instruction memory controller
MPU
High Speed Bus
High Speed Bus
OCD
systemOCD interface
Interrupt controller interface
High
Speed
Bus slave High Speed Bus
High Speed Bus master
Power/
Reset
control Reset interface
CPU Local
Bus
master CPU Local Bus
Data memory controller
CPU RAM High Speed
Bus master
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Figure 4-2. The AVR32UC Pipeline
4.3.2 AVR32A Microarchitecture Compliance
AVR32UC implements an AVR32A microarchitecture. The AVR32A microarchitecture is targeted
at cost-sensitive, lower-end applications like smaller microcontrollers. This
microarchitecture does not provide dedicated hardware registers for shadowing of register file
registers in interrupt contexts. Additionally, it does not provide hardware registers for the return
address registers and return status registers. Instead, all this information is stored on the system
stack. This saves chip area at the expense of slower interrupt handling.
4.3.2.1 Interrupt Handling
Upon interrupt initiation, registers R8-R12 are automatically pushed to the system stack. These
registers are pushed regardless of the priority level of the pending interrupt. The return address
and status register are also automatically pushed to stack. The interrupt handler can therefore
use R8-R12 freely. Upon interrupt completion, the old R8-R12 registers and status register are
restored, and execution continues at the return address stored popped from stack.
The stack is also used to store the status register and return address for exceptions and scall.
Executing the rete or rets instruction at the completion of an exception or system call will pop
this status register and continue execution at the popped return address.
4.3.2.2 Java Support
AVR32UC does not provide Java hardware acceleration.
4.3.2.3 Memory Protection
The MPU allows the user to check all memory accesses for privilege violations. If an access is
attempted to an illegal memory address, the access is aborted and an exception is taken. The
MPU in AVR32UC is specified in the AVR32UC Technical Reference manual.
4.3.2.4 Unaligned Reference Handling
AVR32UC does not support unaligned accesses, except for doubleword accesses. AVR32UC is
able to perform word-aligned st.d and ld.d. Any other unaligned memory access will cause an
IF ID ALU
MUL
Regfile
write
Prefetch unit Decode unit
ALU unit
Multiply unit
Load-store
unit LS
Regfile
Read
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address exception. Doubleword-sized accesses with word-aligned pointers will automatically be
performed as two word-sized accesses.
The following table shows the instructions with support for unaligned addresses. All other
instructions require aligned addresses.
4.3.2.5 Unimplemented Instructions
The following instructions are unimplemented in AVR32UC, and will cause an Unimplemented
Instruction Exception if executed:
• All SIMD instructions
• All coprocessor instructions if no coprocessors are present
• retj, incjosp, popjc, pushjc
• tlbr, tlbs, tlbw
• cache
4.3.2.6 CPU and Architecture Revision
Three major revisions of the AVR32UC CPU currently exist. The device described in this
datasheet uses CPU revision 3.
The Architecture Revision field in the CONFIG0 system register identifies which architecture
revision is implemented in a specific device.
AVR32UC CPU revision 3 is fully backward-compatible with revisions 1 and 2, ie. code compiled
for revision 1 or 2 is binary-compatible with revision 3 CPUs.
Table 4-1. Instructions with Unaligned Reference Support
Instruction Supported Alignment
ld.d Word
st.d Word
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4.4 Programming Model
4.4.1 Register File Configuration
The AVR32UC register file is shown below.
Figure 4-3. The AVR32UC Register File
4.4.2 Status Register Configuration
The Status Register (SR) is split into two halfwords, one upper and one lower, see Figure 4-4
and Figure 4-5. The lower word contains the C, Z, N, V, and Q condition code flags and the R, T,
and L bits, while the upper halfword contains information about the mode and state the processor
executes in. Refer to the AVR32 Architecture Manual for details.
Figure 4-4. The Status Register High Halfword
Application
Bit 0
Supervisor
Bit 31
PC
SR
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R3
R1
R2
R0
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
INT0
SP_APP SP_SYS
R12
R11
R9
R10
R8
INT1 INT2 INT3 Exception NMI
LR LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SYS
LR
Secure
Bit 31 Bit 0
PC
SR
R12
INT0PC
FINTPC
INT1PC
SMPC
R7
R5
R6
R4
R11
R9
R10
R8
R3
R1
R2
R0
SP_SEC
LR
SS_STATUS
SS_ADRF
SS_ADRR
SS_ADR0
SS_ADR1
SS_SP_SYS
SS_SP_APP
SS_RAR
SS_RSR
Bit 31
0 0 0
Bit 16
Interrupt Level 0 Mask
Interrupt Level 1 Mask
Interrupt Level 3 Mask
Interrupt Level 2 Mask
0 0 0 0 0 0 1 1 0 0 0 0 1
- DM D - M2 M1 M0 EM I2MFE I0M GM LC
1 SS
Initial value
I1M Bit name
Mode Bit 0
Mode Bit 1
-
Mode Bit 2
Reserved
Debug State
- I3M
Reserved
Exception Mask
Global Interrupt Mask
Debug State Mask
Secure State
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Figure 4-5. The Status Register Low Halfword
4.4.3 Processor States
4.4.3.1 Normal RISC State
The AVR32 processor supports several different execution contexts as shown in Table 4-2.
Mode changes can be made under software control, or can be caused by external interrupts or
exception processing. A mode can be interrupted by a higher priority mode, but never by one
with lower priority. Nested exceptions can be supported with a minimal software overhead.
When running an operating system on the AVR32, user processes will typically execute in the
application mode. The programs executed in this mode are restricted from executing certain
instructions. Furthermore, most system registers together with the upper halfword of the status
register cannot be accessed. Protected memory areas are also not available. All other operating
modes are privileged and are collectively called System Modes. They have full access to all privileged
and unprivileged resources. After a reset, the processor will be in supervisor mode.
4.4.3.2 Debug State
The AVR32 can be set in a debug state, which allows implementation of software monitor routines
that can read out and alter system information for use during application development. This
implies that all system and application registers, including the status registers and program
counters, are accessible in debug state. The privileged instructions are also available.
All interrupt levels are by default disabled when debug state is entered, but they can individually
be switched on by the monitor routine by clearing the respective mask bit in the status register.
Bit 15 Bit 0
Reserved
Carry
Zero
Sign
0 0 0 0 0 0 0 0 0 0 0 0 0 0
- T - - - - Bit name
0 0 Initial value
- L Q V N Z C
Overflow
Saturation
- - -
Lock
Reserved
Scratch
Table 4-2. Overview of Execution Modes, their Priorities and Privilege Levels.
Priority Mode Security Description
1 Non Maskable Interrupt Privileged Non Maskable high priority interrupt mode
2 Exception Privileged Execute exceptions
3 Interrupt 3 Privileged General purpose interrupt mode
4 Interrupt 2 Privileged General purpose interrupt mode
5 Interrupt 1 Privileged General purpose interrupt mode
6 Interrupt 0 Privileged General purpose interrupt mode
N/A Supervisor Privileged Runs supervisor calls
N/A Application Unprivileged Normal program execution mode
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Debug state can be entered as described in the AVR32UC Technical Reference Manual.
Debug state is exited by the retd instruction.
4.4.3.3 Secure State
The AVR32 can be set in a secure state, that allows a part of the code to execute in a state with
higher security levels. The rest of the code can not access resources reserved for this secure
code. Secure State is used to implement FlashVault technology. Refer to the AVR32UC Technical
Reference Manual for details.
4.4.4 System Registers
The system registers are placed outside of the virtual memory space, and are only accessible
using the privileged mfsr and mtsr instructions. The table below lists the system registers specified
in the AVR32 architecture, some of which are unused in AVR32UC. The programmer is
responsible for maintaining correct sequencing of any instructions following a mtsr instruction.
For detail on the system registers, refer to the AVR32UC Technical Reference Manual.
Table 4-3. System Registers
Reg # Address Name Function
0 0 SR Status Register
1 4 EVBA Exception Vector Base Address
2 8 ACBA Application Call Base Address
3 12 CPUCR CPU Control Register
4 16 ECR Exception Cause Register
5 20 RSR_SUP Unused in AVR32UC
6 24 RSR_INT0 Unused in AVR32UC
7 28 RSR_INT1 Unused in AVR32UC
8 32 RSR_INT2 Unused in AVR32UC
9 36 RSR_INT3 Unused in AVR32UC
10 40 RSR_EX Unused in AVR32UC
11 44 RSR_NMI Unused in AVR32UC
12 48 RSR_DBG Return Status Register for Debug mode
13 52 RAR_SUP Unused in AVR32UC
14 56 RAR_INT0 Unused in AVR32UC
15 60 RAR_INT1 Unused in AVR32UC
16 64 RAR_INT2 Unused in AVR32UC
17 68 RAR_INT3 Unused in AVR32UC
18 72 RAR_EX Unused in AVR32UC
19 76 RAR_NMI Unused in AVR32UC
20 80 RAR_DBG Return Address Register for Debug mode
21 84 JECR Unused in AVR32UC
22 88 JOSP Unused in AVR32UC
23 92 JAVA_LV0 Unused in AVR32UC
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24 96 JAVA_LV1 Unused in AVR32UC
25 100 JAVA_LV2 Unused in AVR32UC
26 104 JAVA_LV3 Unused in AVR32UC
27 108 JAVA_LV4 Unused in AVR32UC
28 112 JAVA_LV5 Unused in AVR32UC
29 116 JAVA_LV6 Unused in AVR32UC
30 120 JAVA_LV7 Unused in AVR32UC
31 124 JTBA Unused in AVR32UC
32 128 JBCR Unused in AVR32UC
33-63 132-252 Reserved Reserved for future use
64 256 CONFIG0 Configuration register 0
65 260 CONFIG1 Configuration register 1
66 264 COUNT Cycle Counter register
67 268 COMPARE Compare register
68 272 TLBEHI Unused in AVR32UC
69 276 TLBELO Unused in AVR32UC
70 280 PTBR Unused in AVR32UC
71 284 TLBEAR Unused in AVR32UC
72 288 MMUCR Unused in AVR32UC
73 292 TLBARLO Unused in AVR32UC
74 296 TLBARHI Unused in AVR32UC
75 300 PCCNT Unused in AVR32UC
76 304 PCNT0 Unused in AVR32UC
77 308 PCNT1 Unused in AVR32UC
78 312 PCCR Unused in AVR32UC
79 316 BEAR Bus Error Address Register
80 320 MPUAR0 MPU Address Register region 0
81 324 MPUAR1 MPU Address Register region 1
82 328 MPUAR2 MPU Address Register region 2
83 332 MPUAR3 MPU Address Register region 3
84 336 MPUAR4 MPU Address Register region 4
85 340 MPUAR5 MPU Address Register region 5
86 344 MPUAR6 MPU Address Register region 6
87 348 MPUAR7 MPU Address Register region 7
88 352 MPUPSR0 MPU Privilege Select Register region 0
89 356 MPUPSR1 MPU Privilege Select Register region 1
Table 4-3. System Registers (Continued)
Reg # Address Name Function
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4.5 Exceptions and Interrupts
In the AVR32 architecture, events are used as a common term for exceptions and interrupts.
AVR32UC incorporates a powerful event handling scheme. The different event sources, like Illegal
Op-code and interrupt requests, have different priority levels, ensuring a well-defined
behavior when multiple events are received simultaneously. Additionally, pending events of a
higher priority class may preempt handling of ongoing events of a lower priority class.
When an event occurs, the execution of the instruction stream is halted, and execution is passed
to an event handler at an address specified in Table 4-4 on page 34. Most of the handlers are
placed sequentially in the code space starting at the address specified by EVBA, with four bytes
between each handler. This gives ample space for a jump instruction to be placed there, jumping
to the event routine itself. A few critical handlers have larger spacing between them, allowing
the entire event routine to be placed directly at the address specified by the EVBA-relative offset
generated by hardware. All interrupt sources have autovectored interrupt service routine (ISR)
addresses. This allows the interrupt controller to directly specify the ISR address as an address
90 360 MPUPSR2 MPU Privilege Select Register region 2
91 364 MPUPSR3 MPU Privilege Select Register region 3
92 368 MPUPSR4 MPU Privilege Select Register region 4
93 372 MPUPSR5 MPU Privilege Select Register region 5
94 376 MPUPSR6 MPU Privilege Select Register region 6
95 380 MPUPSR7 MPU Privilege Select Register region 7
96 384 MPUCRA Unused in this version of AVR32UC
97 388 MPUCRB Unused in this version of AVR32UC
98 392 MPUBRA Unused in this version of AVR32UC
99 396 MPUBRB Unused in this version of AVR32UC
100 400 MPUAPRA MPU Access Permission Register A
101 404 MPUAPRB MPU Access Permission Register B
102 408 MPUCR MPU Control Register
103 412 SS_STATUS Secure State Status Register
104 416 SS_ADRF Secure State Address Flash Register
105 420 SS_ADRR Secure State Address RAM Register
106 424 SS_ADR0 Secure State Address 0 Register
107 428 SS_ADR1 Secure State Address 1 Register
108 432 SS_SP_SYS Secure State Stack Pointer System Register
109 436 SS_SP_APP Secure State Stack Pointer Application Register
110 440 SS_RAR Secure State Return Address Register
111 444 SS_RSR Secure State Return Status Register
112-191 448-764 Reserved Reserved for future use
192-255 768-1020 IMPL IMPLEMENTATION DEFINED
Table 4-3. System Registers (Continued)
Reg # Address Name Function
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relative to EVBA. The autovector offset has 14 address bits, giving an offset of maximum 16384
bytes. The target address of the event handler is calculated as (EVBA | event_handler_offset),
not (EVBA + event_handler_offset), so EVBA and exception code segments must be set up
appropriately. The same mechanisms are used to service all different types of events, including
interrupt requests, yielding a uniform event handling scheme.
An interrupt controller does the priority handling of the interrupts and provides the autovector offset
to the CPU.
4.5.1 System Stack Issues
Event handling in AVR32UC uses the system stack pointed to by the system stack pointer,
SP_SYS, for pushing and popping R8-R12, LR, status register, and return address. Since event
code may be timing-critical, SP_SYS should point to memory addresses in the IRAM section,
since the timing of accesses to this memory section is both fast and deterministic.
The user must also make sure that the system stack is large enough so that any event is able to
push the required registers to stack. If the system stack is full, and an event occurs, the system
will enter an UNDEFINED state.
4.5.2 Exceptions and Interrupt Requests
When an event other than scall or debug request is received by the core, the following actions
are performed atomically:
1. The pending event will not be accepted if it is masked. The I3M, I2M, I1M, I0M, EM, and
GM bits in the Status Register are used to mask different events. Not all events can be
masked. A few critical events (NMI, Unrecoverable Exception, TLB Multiple Hit, and
Bus Error) can not be masked. When an event is accepted, hardware automatically
sets the mask bits corresponding to all sources with equal or lower priority. This inhibits
acceptance of other events of the same or lower priority, except for the critical events
listed above. Software may choose to clear some or all of these bits after saving the
necessary state if other priority schemes are desired. It is the event source’s responsability
to ensure that their events are left pending until accepted by the CPU.
2. When a request is accepted, the Status Register and Program Counter of the current
context is stored to the system stack. If the event is an INT0, INT1, INT2, or INT3, registers
R8-R12 and LR are also automatically stored to stack. Storing the Status
Register ensures that the core is returned to the previous execution mode when the
current event handling is completed. When exceptions occur, both the EM and GM bits
are set, and the application may manually enable nested exceptions if desired by clearing
the appropriate bit. Each exception handler has a dedicated handler address, and
this address uniquely identifies the exception source.
3. The Mode bits are set to reflect the priority of the accepted event, and the correct register
file bank is selected. The address of the event handler, as shown in Table 4-4 on
page 34, is loaded into the Program Counter.
The execution of the event handler routine then continues from the effective address calculated.
The rete instruction signals the end of the event. When encountered, the Return Status Register
and Return Address Register are popped from the system stack and restored to the Status Register
and Program Counter. If the rete instruction returns from INT0, INT1, INT2, or INT3,
registers R8-R12 and LR are also popped from the system stack. The restored Status Register
contains information allowing the core to resume operation in the previous execution mode. This
concludes the event handling.
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4.5.3 Supervisor Calls
The AVR32 instruction set provides a supervisor mode call instruction. The scall instruction is
designed so that privileged routines can be called from any context. This facilitates sharing of
code between different execution modes. The scall mechanism is designed so that a minimal
execution cycle overhead is experienced when performing supervisor routine calls from timecritical
event handlers.
The scall instruction behaves differently depending on which mode it is called from. The behaviour
is detailed in the instruction set reference. In order to allow the scall routine to return to the
correct context, a return from supervisor call instruction, rets, is implemented. In the AVR32UC
CPU, scall and rets uses the system stack to store the return address and the status register.
4.5.4 Debug Requests
The AVR32 architecture defines a dedicated Debug mode. When a debug request is received by
the core, Debug mode is entered. Entry into Debug mode can be masked by the DM bit in the
status register. Upon entry into Debug mode, hardware sets the SR.D bit and jumps to the
Debug Exception handler. By default, Debug mode executes in the exception context, but with
dedicated Return Address Register and Return Status Register. These dedicated registers
remove the need for storing this data to the system stack, thereby improving debuggability. The
Mode bits in the Status Register can freely be manipulated in Debug mode, to observe registers
in all contexts, while retaining full privileges.
Debug mode is exited by executing the retd instruction. This returns to the previous context.
4.5.5 Entry Points for Events
Several different event handler entry points exist. In AVR32UC, the reset address is
0x80000000. This places the reset address in the boot flash memory area.
TLB miss exceptions and scall have a dedicated space relative to EVBA where their event handler
can be placed. This speeds up execution by removing the need for a jump instruction placed
at the program address jumped to by the event hardware. All other exceptions have a dedicated
event routine entry point located relative to EVBA. The handler routine address identifies the
exception source directly.
AVR32UC uses the ITLB and DTLB protection exceptions to signal a MPU protection violation.
ITLB and DTLB miss exceptions are used to signal that an access address did not map to any of
the entries in the MPU. TLB multiple hit exception indicates that an access address did map to
multiple TLB entries, signalling an error.
All interrupt requests have entry points located at an offset relative to EVBA. This autovector offset
is specified by an interrupt controller. The programmer must make sure that none of the
autovector offsets interfere with the placement of other code. The autovector offset has 14
address bits, giving an offset of maximum 16384 bytes.
Special considerations should be made when loading EVBA with a pointer. Due to security considerations,
the event handlers should be located in non-writeable flash memory, or optionally in
a privileged memory protection region if an MPU is present.
If several events occur on the same instruction, they are handled in a prioritized way. The priority
ordering is presented in Table 4-4 on page 34. If events occur on several instructions at different
locations in the pipeline, the events on the oldest instruction are always handled before any
events on any younger instruction, even if the younger instruction has events of higher priority
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than the oldest instruction. An instruction B is younger than an instruction A if it was sent down
the pipeline later than A.
The addresses and priority of simultaneous events are shown in Table 4-4 on page 34. Some of
the exceptions are unused in AVR32UC since it has no MMU, coprocessor interface, or floatingpoint
unit.
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Table 4-4. Priority and Handler Addresses for Events
Priority Handler Address Name Event source Stored Return Address
1 0x80000000 Reset External input Undefined
2 Provided by OCD system OCD Stop CPU OCD system First non-completed instruction
3 EVBA+0x00 Unrecoverable exception Internal PC of offending instruction
4 EVBA+0x04 TLB multiple hit MPU PC of offending instruction
5 EVBA+0x08 Bus error data fetch Data bus First non-completed instruction
6 EVBA+0x0C Bus error instruction fetch Data bus First non-completed instruction
7 EVBA+0x10 NMI External input First non-completed instruction
8 Autovectored Interrupt 3 request External input First non-completed instruction
9 Autovectored Interrupt 2 request External input First non-completed instruction
10 Autovectored Interrupt 1 request External input First non-completed instruction
11 Autovectored Interrupt 0 request External input First non-completed instruction
12 EVBA+0x14 Instruction Address CPU PC of offending instruction
13 EVBA+0x50 ITLB Miss MPU PC of offending instruction
14 EVBA+0x18 ITLB Protection MPU PC of offending instruction
15 EVBA+0x1C Breakpoint OCD system First non-completed instruction
16 EVBA+0x20 Illegal Opcode Instruction PC of offending instruction
17 EVBA+0x24 Unimplemented instruction Instruction PC of offending instruction
18 EVBA+0x28 Privilege violation Instruction PC of offending instruction
19 EVBA+0x2C Floating-point UNUSED
20 EVBA+0x30 Coprocessor absent Instruction PC of offending instruction
21 EVBA+0x100 Supervisor call Instruction PC(Supervisor Call) +2
22 EVBA+0x34 Data Address (Read) CPU PC of offending instruction
23 EVBA+0x38 Data Address (Write) CPU PC of offending instruction
24 EVBA+0x60 DTLB Miss (Read) MPU PC of offending instruction
25 EVBA+0x70 DTLB Miss (Write) MPU PC of offending instruction
26 EVBA+0x3C DTLB Protection (Read) MPU PC of offending instruction
27 EVBA+0x40 DTLB Protection (Write) MPU PC of offending instruction
28 EVBA+0x44 DTLB Modified UNUSED
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5. Memories
5.1 Embedded Memories
• Internal high-speed flash
– 256Kbytes (ATUC256L3U, ATUC256L4U)
– 128Kbytes (ATUC128L3U, ATUC128L4U)
– 64Kbytes (ATUC64L3U, ATUC64L4U)
• 0 wait state access at up to 25MHz in worst case conditions
• 1 wait state access at up to 50MHz in worst case conditions
• Pipelined flash architecture, allowing burst reads from sequential flash locations, hiding
penalty of 1 wait state access
• Pipelined flash architecture typically reduces the cycle penalty of 1 wait state operation
to only 8% compared to 0 wait state operation
• 100 000 write cycles, 15-year data retention capability
• Sector lock capabilities, bootloader protection, security bit
• 32 fuses, erased during chip erase
• User page for data to be preserved during chip erase
• Internal high-speed SRAM, single-cycle access at full speed
– 32Kbytes (ATUC256L3U, ATUC256L4U, ATUC128L3U, ATUC128L4U)
– 16Kbytes (ATUC64L3U, ATUC64L4U)
5.2 Physical Memory Map
The system bus is implemented as a bus matrix. All system bus addresses are fixed, and they
are never remapped in any way, not even during boot. Note that AVR32 UC CPU uses unsegmented
translation, as described in the AVR32 Architecture Manual. The 32-bit physical address
space is mapped as follows:
Table 5-1. ATUC64/128/256L3/4U Physical Memory Map
Memory Start Address
Size
ATUC256L3U, ATUC256L4U ATUC128L3U, ATUC128L4U ATUC64L3U, ATUC64L4U
Embedded SRAM 0x00000000 32Kbytes 32Kbytes 16Kbytes
Embedded Flash 0x80000000 256Kbytes 128Kbytes 64Kbytes
SAU Channels 0x90000000 256 bytes 256 bytes 256 bytes
HSB-PB Bridge B 0xFFFE0000 64Kbytes 64Kbytes 64Kbytes
HSB-PB Bridge A 0xFFFF0000 64Kbytes 64Kbytes 64Kbytes
Table 5-2. Flash Memory Parameters
Device Flash Size (FLASH_PW) Number of Pages (FLASH_P) Page Size (FLASH_W)
ATUC256L3U,
ATUC256L4U 256Kbytes 512 512 bytes
ATUC128L3U,
ATUC128L4U 128Kbytes 256 512 bytes
ATUC64L3U,
ATUC64L4U 64Kbytes 128 512 bytes
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5.3 Peripheral Address Map
Table 5-3. Peripheral Address Mapping
Address Peripheral Name
0xFFFE0000
FLASHCDW Flash Controller - FLASHCDW
0xFFFE0400
HMATRIX HSB Matrix - HMATRIX
0xFFFE0800
SAU Secure Access Unit - SAU
0xFFFE1000
USBC USB 2.0 Interface - USBC
0xFFFF0000
PDCA Peripheral DMA Controller - PDCA
0xFFFF1000
INTC Interrupt controller - INTC
0xFFFF1400
PM Power Manager - PM
0xFFFF1800
SCIF System Control Interface - SCIF
0xFFFF1C00
AST Asynchronous Timer - AST
0xFFFF2000
WDT Watchdog Timer - WDT
0xFFFF2400
EIC External Interrupt Controller - EIC
0xFFFF2800
FREQM Frequency Meter - FREQM
0xFFFF2C00
GPIO General-Purpose Input/Output Controller - GPIO
0xFFFF3000
USART0 Universal Synchronous Asynchronous Receiver
Transmitter - USART0
0xFFFF3400
USART1 Universal Synchronous Asynchronous Receiver
Transmitter - USART1
0xFFFF3800
USART2 Universal Synchronous Asynchronous Receiver
Transmitter - USART2
0xFFFF3C00
USART3 Universal Synchronous Asynchronous Receiver
Transmitter - USART3
0xFFFF4000
SPI Serial Peripheral Interface - SPI
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5.4 CPU Local Bus Mapping
Some of the registers in the GPIO module are mapped onto the CPU local bus, in addition to
being mapped on the Peripheral Bus. These registers can therefore be reached both by
accesses on the Peripheral Bus, and by accesses on the local bus.
Mapping these registers on the local bus allows cycle-deterministic toggling of GPIO pins since
the CPU and GPIO are the only modules connected to this bus. Also, since the local bus runs at
CPU speed, one write or read operation can be performed per clock cycle to the local busmapped
GPIO registers.
0xFFFF4400
TWIM0 Two-wire Master Interface - TWIM0
0xFFFF4800
TWIM1 Two-wire Master Interface - TWIM1
0xFFFF4C00
TWIS0 Two-wire Slave Interface - TWIS0
0xFFFF5000
TWIS1 Two-wire Slave Interface - TWIS1
0xFFFF5400
PWMA Pulse Width Modulation Controller - PWMA
0xFFFF5800
TC0 Timer/Counter - TC0
0xFFFF5C00
TC1 Timer/Counter - TC1
0xFFFF6000
ADCIFB ADC Interface - ADCIFB
0xFFFF6400
ACIFB Analog Comparator Interface - ACIFB
0xFFFF6800
CAT Capacitive Touch Module - CAT
0xFFFF6C00
GLOC Glue Logic Controller - GLOC
0xFFFF7000
AW aWire - AW
0xFFFF7400
ABDACB Audio Bitstream DAC - ABDACB
0xFFFF7800
IISC Inter-IC Sound (I2S) Controller - IISC
Table 5-3. Peripheral Address Mapping
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The following GPIO registers are mapped on the local bus:
Table 5-4. Local Bus Mapped GPIO Registers
Port Register Mode
Local Bus
Address Access
0 Output Driver Enable Register (ODER) WRITE 0x40000040 Write-only
SET 0x40000044 Write-only
CLEAR 0x40000048 Write-only
TOGGLE 0x4000004C Write-only
Output Value Register (OVR) WRITE 0x40000050 Write-only
SET 0x40000054 Write-only
CLEAR 0x40000058 Write-only
TOGGLE 0x4000005C Write-only
Pin Value Register (PVR) - 0x40000060 Read-only
1 Output Driver Enable Register (ODER) WRITE 0x40000140 Write-only
SET 0x40000144 Write-only
CLEAR 0x40000148 Write-only
TOGGLE 0x4000014C Write-only
Output Value Register (OVR) WRITE 0x40000150 Write-only
SET 0x40000154 Write-only
CLEAR 0x40000158 Write-only
TOGGLE 0x4000015C Write-only
Pin Value Register (PVR) - 0x40000160 Read-only
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6. Supply and Startup Considerations
6.1 Supply Considerations
6.1.1 Power Supplies
The ATUC64/128/256L3/4U has several types of power supply pins:
• VDDIO: Powers I/O lines. Voltage is 1.8 to 3.3V nominal.
• VDDIN: Powers I/O lines, the USB pins, and the internal regulator. Voltage is 1.8 to 3.3V
nominal if USB is not used, and 3.3V nominal when USB is used.
• VDDANA: Powers the ADC. Voltage is 1.8V nominal.
• VDDCORE: Powers the core, memories, and peripherals. Voltage is 1.8V nominal.
The ground pins GND are common to VDDCORE, VDDIO, and VDDIN. The ground pin for
VDDANA is GNDANA.
When VDDCORE is not connected to VDDIN, the VDDIN voltage must be higher than 1.98V.
Refer to Section 35. on page 897 for power consumption on the various supply pins.
For decoupling recommendations for the different power supplies, please refer to the schematic
checklist.
Refer to Section on page 10 for power supply connections for I/O pins.
6.1.2 Voltage Regulator
The ATUC64/128/256L3/4U embeds a voltage regulator that converts from 3.3V nominal to
1.8V with a load of up to 60 mA. The regulator supplies the output voltage on VDDCORE. The
regulator may only be used to drive internal circuitry in the device. VDDCORE should be externally
connected to the 1.8V domains. See Section 6.1.3 for regulator connection figures.
Adequate output supply decoupling is mandatory for VDDCORE to reduce ripple and avoid
oscillations. The best way to achieve this is to use two capacitors in parallel between VDDCORE
and GND as close to the device as possible. Please refer to Section 35.8 on page 911 for
decoupling capacitors values and regulator characteristics.
Figure 6-1. Supply Decoupling.
The voltage regulator can be turned off in the shutdown mode to power down the core logic and
keep a small part of the system powered in order to reduce power consumption. To enter this
mode the 3.3V supply mode, with 1.8V regulated I/O lines power supply configuration must be
used.
3.3V
1.8V
VDDIN
VDDCORE
1.8V
Regulator
CIN1
COUT1 COUT2
C IN3 IN2 C
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6.1.3 Regulator Connection
The ATUC64/128/256L3/4U supports three power supply configurations:
• 3.3V single supply mode
– Shutdown mode is not available
• 1.8V single supply mode
– Shutdown mode is not available
• 3.3V supply mode, with 1.8V regulated I/O lines
– Shutdown mode is available
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6.1.3.1 3.3V Single Supply Mode
In 3.3V single supply mode the internal regulator is connected to the 3.3V source (VDDIN pin)
and its output feeds VDDCORE. Figure 6-2 shows the power schematics to be used for 3.3V
single supply mode. All I/O lines will be powered by the same power (VDDIN=VDDIO).
Figure 6-2. 3.3V Single Supply Mode
VDDIO
VDDCORE
+
- 1.98-3.6V
VDDANA ADC
VDDIN GND
GNDANA
CPU,
Peripherals,
Memories,
SCIF, BOD,
RCSYS,
DFLL, PLL
OSC32K,
RC32K,
POR33,
SM33
I/O Pins I/O Pins
OSC32K_2,
AST, Wake,
Regulator
control
Linear
regulator
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6.1.3.2 1.8V Single Supply Mode
In 1.8V single supply mode the internal regulator is not used, and VDDIO and VDDCORE are
powered by a single 1.8V supply as shown in Figure 6-3. All I/O lines will be powered by the
same power (VDDIN = VDDIO = VDDCORE).
Figure 6-3. 1.8V Single Supply Mode
VDDIO
VDDCORE
+
-
1.62-1.98V
VDDANA ADC
VDDIN GND
GNDANA
CPU,
Peripherals,
Memories,
SCIF, BOD,
RCSYS,
DFLL, PLL
OSC32K,
RC32K,
POR33,
SM33
I/O Pins I/O Pins
OSC32K_2,
AST, Wake,
Regulator
control
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6.1.3.3 3.3V Supply Mode with 1.8V Regulated I/O Lines
In this mode, the internal regulator is connected to the 3.3V source and its output is connected
to both VDDCORE and VDDIO as shown in Figure 6-4. This configuration is required in order to
use Shutdown mode.
Figure 6-4. 3.3V Supply Mode with 1.8V Regulated I/O Lines
In this mode, some I/O lines are powered by VDDIN while other I/O lines are powered by VDDIO.
Refer to Section on page 10 for description of power supply for each I/O line.
Refer to the Power Manager chapter for a description of what parts of the system are powered in
Shutdown mode.
Important note: As the regulator has a maximum output current of 60 mA, this mode can only be
used in applications where the maximum I/O current is known and compatible with the core and
peripheral power consumption. Typically, great care must be used to ensure that only a few I/O
lines are toggling at the same time and drive very small loads.
VDDIO
VDDCORE
+
- 1.98-3.6V
VDDANA ADC
VDDIN GND
GNDANA
CPU,
Peripherals,
Memories,
SCIF, BOD,
RCSYS,
DFLL, PLL
OSC32K,
RC32K,
POR33,
SM33
I/O Pins I/O Pins
OSC32K_2,
AST, Wake,
Regulator
control
Linear
regulator
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6.1.4 Power-up Sequence
6.1.4.1 Maximum Rise Rate
To avoid risk of latch-up, the rise rate of the power supplies must not exceed the values
described in Table 35-3 on page 898.
Recommended order for power supplies is also described in this chapter.
6.1.4.2 Minimum Rise Rate
The integrated Power-on Reset (POR33) circuitry monitoring the VDDIN powering supply
requires a minimum rise rate for the VDDIN power supply.
See Table 35-3 on page 898 for the minimum rise rate value.
If the application can not ensure that the minimum rise rate condition for the VDDIN power supply
is met, one of the following configurations can be used:
• A logic “0” value is applied during power-up on pin PA11 (WAKE_N) until VDDIN rises above
1.2V.
• A logic “0” value is applied during power-up on pin RESET_N until VDDIN rises above 1.2V.
6.2 Startup Considerations
This chapter summarizes the boot sequence of the ATUC64/128/256L3/4U. The behavior after
power-up is controlled by the Power Manager. For specific details, refer to the Power Manager
chapter.
6.2.1 Starting of Clocks
After power-up, the device will be held in a reset state by the Power-on Reset (POR18 and
POR33) circuitry for a short time to allow the power to stabilize throughout the device. After
reset, the device will use the System RC Oscillator (RCSYS) as clock source. Please refer to
Table 35-17 on page 910 for the frequency for this oscillator.
On system start-up, all high-speed clocks are disabled. All clocks to all modules are running. No
clocks have a divided frequency; all parts of the system receive a clock with the same frequency
as the System RC Oscillator.
When powering up the device, there may be a delay before the voltage has stabilized, depending
on the rise time of the supply used. The CPU can start executing code as soon as the supply
is above the POR18 and POR33 thresholds, and before the supply is stable. Before switching to
a high-speed clock source, the user should use the BOD to make sure the VDDCORE is above
the minimum level (1.62V).
6.2.2 Fetching of Initial Instructions
After reset has been released, the AVR32 UC CPU starts fetching instructions from the reset
address, which is 0x80000000. This address points to the first address in the internal Flash.
The code read from the internal flash is free to configure the clock system and clock sources.
Please refer to the PM and SCIF chapters for more details.
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7. Peripheral DMA Controller (PDCA)
Rev: 1.2.3.1
7.1 Features
• Multiple channels
• Generates transfers between memories and peripherals such as USART and SPI
• Two address pointers/counters per channel allowing double buffering
• Performance monitors to measure average and maximum transfer latency
• Optional synchronizing of data transfers with extenal peripheral events
• Ring buffer functionality
7.2 Overview
The Peripheral DMA Controller (PDCA) transfers data between on-chip peripheral modules such
as USART, SPI and memories (those memories may be on- and off-chip memories). Using the
PDCA avoids CPU intervention for data transfers, improving the performance of the microcontroller.
The PDCA can transfer data from memory to a peripheral or from a peripheral to memory.
The PDCA consists of multiple DMA channels. Each channel has:
• A Peripheral Select Register
• A 32-bit memory pointer
• A 16-bit transfer counter
• A 32-bit memory pointer reload value
• A 16-bit transfer counter reload value
The PDCA communicates with the peripheral modules over a set of handshake interfaces. The
peripheral signals the PDCA when it is ready to receive or transmit data. The PDCA acknowledges
the request when the transmission has started.
When a transmit buffer is empty or a receive buffer is full, an optional interrupt request can be
generated.
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7.3 Block Diagram
Figure 7-1. PDCA Block Diagram
7.4 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
7.4.1 Power Management
If the CPU enters a sleep mode that disables the PDCA clocks, the PDCA will stop functioning
and resume operation after the system wakes up from sleep mode.
7.4.2 Clocks
The PDCA has two bus clocks connected: One High Speed Bus clock (CLK_PDCA_HSB) and
one Peripheral Bus clock (CLK_PDCA_PB). These clocks are generated by the Power Manager.
Both clocks are enabled at reset, and can be disabled in the Power Manager. It is
recommended to disable the PDCA before disabling the clocks, to avoid freezing the PDCA in
an undefined state.
7.4.3 Interrupts
The PDCA interrupt request lines are connected to the interrupt controller. Using the PDCA
interrupts requires the interrupt controller to be programmed first.
HSB to PB
Bridge
Peripheral DMA
Controller
(PDCA)
Peripheral
0
High Speed
Bus Matrix
Handshake Interfaces Peripheral Bus
IRQ
HSB
HSB
Interrupt
Controller
Peripheral
1
Peripheral
2
Peripheral
(n-1) ...
Memory
HSB
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7.4.4 Peripheral Events
The PDCA peripheral events are connected via the Peripheral Event System. Refer to the
Peripheral Event System chapter for details.
7.5 Functional Description
7.5.1 Basic Operation
The PDCA consists of multiple independent PDCA channels, each capable of handling DMA
requests in parallel. Each PDCA channels contains a set of configuration registers which must
be configured to start a DMA transfer.
In this section the steps necessary to configure one PDCA channel is outlined.
The peripheral to transfer data to or from must be configured correctly in the Peripheral Select
Register (PSR). This is performed by writing the Peripheral Identity (PID) value for the corresponding
peripheral to the PID field in the PSR register. The PID also encodes the transfer
direction, i.e. memory to peripheral or peripheral to memory. See Section 7.5.6.
The transfer size must be written to the Transfer Size field in the Mode Register (MR.SIZE). The
size must match the data size produced or consumed by the selected peripheral. See Section
7.5.7.
The memory address to transfer to or from, depending on the PSR, must be written to the Memory
Address Register (MAR). For each transfer the memory address is increased by either a
one, two or four, depending on the size set in MR. See Section 7.5.2.
The number of data items to transfer is written to the TCR register. If the PDCA channel is
enabled, a transfer will start immediately after writing a non-zero value to TCR or the reload version
of TCR, TCRR. After each transfer the TCR value is decreased by one. Both MAR and TCR
can be read while the PDCA channel is active to monitor the DMA progress. See Section 7.5.3.
The channel must be enabled for a transfer to start. A channel is enable by writing a one to the
EN bit in the Control Register (CR).
7.5.2 Memory Pointer
Each channel has a 32-bit Memory Address Register (MAR). This register holds the memory
address for the next transfer to be performed. The register is automatically updated after each
transfer. The address will be increased by either one, two or four depending on the size of the
DMA transfer (byte, halfword or word). The MAR can be read at any time during transfer.
7.5.3 Transfer Counter
Each channel has a 16-bit Transfer Counter Register (TCR). This register must be written with
the number of transfers to be performed. The TCR register should contain the number of data
items to be transferred independently of the transfer size. The TCR can be read at any time during
transfer to see the number of remaining transfers.
7.5.4 Reload Registers
Both the MAR and the TCR have a reload register, respectively Memory Address Reload Register
(MARR) and Transfer Counter Reload Register (TCRR). These registers provide the
possibility for the PDCA to work on two memory buffers for each channel. When one buffer has
completed, MAR and TCR will be reloaded with the values in MARR and TCRR. The reload logic
is always enabled and will trigger if the TCR reaches zero while TCRR holds a non-zero value.
After reload, the MARR and TCRR registers are cleared.
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If TCR is zero when writing to TCRR, the TCR and MAR are automatically updated with the
value written in TCRR and MARR.
7.5.5 Ring Buffer
When Ring Buffer mode is enabled the TCRR and MARR registers will not be cleared when
TCR and MAR registers reload. This allows the PDCA to read or write to the same memory
region over and over again until the transfer is actively stopped by the user. Ring Buffer mode is
enabled by writing a one to the Ring Buffer bit in the Mode Register (MR.RING).
7.5.6 Peripheral Selection
The Peripheral Select Register (PSR) decides which peripheral should be connected to the
PDCA channel. A peripheral is selected by writing the corresponding Peripheral Identity (PID) to
the PID field in the PSR register. Writing the PID will both select the direction of the transfer
(memory to peripheral or peripheral to memory), which handshake interface to use, and the
address of the peripheral holding register. Refer to the Peripheral Identity (PID) table in the Module
Configuration section for the peripheral PID values.
7.5.7 Transfer Size
The transfer size can be set individually for each channel to be either byte, halfword or word (8-
bit, 16-bit or 32-bit respectively). Transfer size is set by writing the desired value to the Transfer
Size field in the Mode Register (MR.SIZE).
When the PDCA moves data between peripherals and memory, data is automatically sized and
aligned. When memory is accessed, the size specified in MR.SIZE and system alignment is
used. When a peripheral register is accessed the data to be transferred is converted to a word
where bit n in the data corresponds to bit n in the peripheral register. If the transfer size is byte or
halfword, bits greater than 8 and16 respectively are set to zero.
Refer to the Module Configuration section for information regarding what peripheral registers are
used for the different peripherals and then to the peripheral specific chapter for information
about the size option available for the different registers.
7.5.8 Enabling and Disabling
Each DMA channel is enabled by writing a one to the Transfer Enable bit in the Control Register
(CR.TEN) and disabled by writing a one to the Transfer Disable bit (CR.TDIS). The current status
can be read from the Status Register (SR).
While the PDCA channel is enabled all DMA request will be handled as long the TCR and TCRR
is not zero.
7.5.9 Interrupts
Interrupts can be enabled by writing a one to the corresponding bit in the Interrupt Enable Register
(IER) and disabled by writing a one to the corresponding bit in the Interrupt Disable Register
(IDR). The Interrupt Mask Register (IMR) can be read to see whether an interrupt is enabled or
not. The current status of an interrupt source can be read through the Interrupt Status Register
(ISR).
The PDCA has three interrupt sources:
• Reload Counter Zero - The TCRR register is zero.
• Transfer Finished - Both the TCR and TCRR registers are zero.
• Transfer Error - An error has occurred in accessing memory.
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7.5.10 Priority
If more than one PDCA channel is requesting transfer at a given time, the PDCA channels are
prioritized by their channel number. Channels with lower numbers have priority over channels
with higher numbers, giving channel zero the highest priority.
7.5.11 Error Handling
If the Memory Address Register (MAR) is set to point to an invalid location in memory, an error
will occur when the PDCA tries to perform a transfer. When an error occurs, the Transfer Error
bit in the Interrupt Status Register (ISR.TERR) will be set and the DMA channel that caused the
error will be stopped. In order to restart the channel, the user must program the Memory
Address Register to a valid address and then write a one to the Error Clear bit in the Control
Register (CR.ECLR). If the Transfer Error interrupt is enabled, an interrupt request will be generated
when a transfer error occurs.
7.5.12 Peripheral Event Trigger
Peripheral events can be used to trigger PDCA channel transfers. Peripheral Event synchronizations
are enabled by writing a one to the Event Trigger bit in the Mode Register (MR.ETRIG).
When set, all DMA requests will be blocked until a peripheral event is received. For each peripheral
event received, only one data item is transferred. If no DMA requests are pending when a
peripheral event is received, the PDCA will start a transfer as soon as a peripheral event is
detected. If multiple events are received while the PDCA channel is busy transferring data, an
overflow condition will be signaled in the Peripheral Event System. Refer to the Peripheral Event
System chapter for more information.
7.6 Performance Monitors
Up to two performance monitors allow the user to measure the activity and stall cycles for PDCA
transfers. To monitor a PDCA channel, the corresponding channel number must be written to
one of the MON0/1CH fields in the Performance Control Register (PCONTROL) and a one must
be written to the corresponding CH0/1EN bit in the same register.
Due to performance monitor hardware resource sharing, the two monitor channels should NOT
be programmed to monitor the same PDCA channel. This may result in UNDEFINED performance
monitor behavior.
7.6.1 Measuring mechanisms
Three different parameters can be measured by each channel:
• The number of data transfer cycles since last channel reset, both for read and write
• The number of stall cycles since last channel reset, both for read and write
• The maximum latency since last channel reset, both for read and write
These measurements can be extracted by software and used to generate indicators for bus
latency, bus load, and maximum bus latency.
Each of the counters has a fixed width, and may therefore overflow. When an overflow is
encountered in either the Performance Channel Data Read/Write Cycle registers (PRDATA0/1
and PWDATA0/1) or the Performance Channel Read/Write Stall Cycles registers (PRSTALL0/1
and PWSTALL0/1) of a channel, all registers in the channel are reset. This behavior is altered if
the Channel Overflow Freeze bit is one in the Performance Control register (PCONTROL.CH0/1OVF).
If this bit is one, the channel registers are frozen when either DATA or
STALL reaches its maximum value. This simplifies one-shot readout of the counter values.
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The registers can also be manually reset by writing a one to the Channel Reset bit in the PCONTROL
register (PCONTROL.CH0/1RES). The Performance Channel Read/Write Latency
registers (PRLAT0/1 and PWLAT0/1) are saturating when their maximum count value is
reached. The PRLAT0/1 and PWLAT0/1 registers can only be reset by writing a one to the corresponding
reset bit in PCONTROL (PCONTROL.CH0/1RES).
A counter is enabled by writing a one to the Channel Enable bit in the Performance Control Register
(PCONTROL.CH0/1EN).
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7.7 User Interface
7.7.1 Memory Map Overview
The channels are mapped as shown in Table 7-1. Each channel has a set of configuration registers,
shown in Table 7-2, where n is the channel number.
7.7.2 Channel Memory Map
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the
end of this chapter.
Table 7-1. PDCA Register Memory Map
Address Range Contents
0x000 - 0x03F DMA channel 0 configuration registers
0x040 - 0x07F DMA channel 1 configuration registers
... ...
(0x000 - 0x03F)+m*0x040 DMA channel m configuration registers
0x800-0x830 Performance Monitor registers
0x834 Version register
Table 7-2. PDCA Channel Configuration Registers
Offset Register Register Name Access Reset
0x000 + n*0x040 Memory Address Register MAR Read/Write 0x00000000
0x004 + n*0x040 Peripheral Select Register PSR Read/Write - (1)
0x008 + n*0x040 Transfer Counter Register TCR Read/Write 0x00000000
0x00C + n*0x040 Memory Address Reload Register MARR Read/Write 0x00000000
0x010 + n*0x040 Transfer Counter Reload Register TCRR Read/Write 0x00000000
0x014 + n*0x040 Control Register CR Write-only 0x00000000
0x018 + n*0x040 Mode Register MR Read/Write 0x00000000
0x01C + n*0x040 Status Register SR Read-only 0x00000000
0x020 + n*0x040 Interrupt Enable Register IER Write-only 0x00000000
0x024 + n*0x040 Interrupt Disable Register IDR Write-only 0x00000000
0x028 + n*0x040 Interrupt Mask Register IMR Read-only 0x00000000
0x02C + n*0x040 Interrupt Status Register ISR Read-only 0x00000000
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7.7.3 Performance Monitor Memory Map
Note: 1. The number of performance monitors is device specific. If the device has only one performance
monitor, the Channel1 registers are not available. Please refer to the Module
Configuration section at the end of this chapter for the number of performance monitors on this
device.
7.7.4 Version Register Memory Map
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 7-3. PDCA Performance Monitor Registers(1)
Offset Register Register Name Access Reset
0x800 Performance Control Register PCONTROL Read/Write 0x00000000
0x804 Channel0 Read Data Cycles PRDATA0 Read-only 0x00000000
0x808 Channel0 Read Stall Cycles PRSTALL0 Read-only 0x00000000
0x80C Channel0 Read Max Latency PRLAT0 Read-only 0x00000000
0x810 Channel0 Write Data Cycles PWDATA0 Read-only 0x00000000
0x814 Channel0 Write Stall Cycles PWSTALL0 Read-only 0x00000000
0x818 Channel0 Write Max Latency PWLAT0 Read-only 0x00000000
0x81C Channel1 Read Data Cycles PRDATA1 Read-only 0x00000000
0x820 Channel1 Read Stall Cycles PRSTALL1 Read-only 0x00000000
0x824 Channel1 Read Max Latency PRLAT1 Read-only 0x00000000
0x828 Channel1 Write Data Cycles PWDATA1 Read-only 0x00000000
0x82C Channel1 Write Stall Cycles PWSTALL1 Read-only 0x00000000
0x830 Channel1 Write Max Latency PWLAT1 Read-only 0x00000000
Table 7-4. PDCA Version Register Memory Map
Offset Register Register Name Access Reset
0x834 Version Register VERSION Read-only - (1)
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7.7.5 Memory Address Register
Name: MAR
Access Type: Read/Write
Offset: 0x000 + n*0x040
Reset Value: 0x00000000
• MADDR: Memory Address
Address of memory buffer. MADDR should be programmed to point to the start of the memory buffer when configuring the
PDCA. During transfer, MADDR will point to the next memory location to be read/written.
31 30 29 28 27 26 25 24
MADDR[31:24]
23 22 21 20 19 18 17 16
MADDR[23:16]
15 14 13 12 11 10 9 8
MADDR[15:8]
76543210
MADDR[7:0]
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7.7.6 Peripheral Select Register
Name: PSR
Access Type: Read/Write
Offset: 0x004 + n*0x040
Reset Value: -
• PID: Peripheral Identifier
The Peripheral Identifier selects which peripheral should be connected to the DMA channel. Writing a PID will select both which
handshake interface to use, the direction of the transfer and also the address of the Receive/Transfer Holding Register for the
peripheral. See the Module Configuration section of PDCA for details. The width of the PID field is device specific and
dependent on the number of peripheral modules in the device.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
PID
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7.7.7 Transfer Counter Register
Name: TCR
Access Type: Read/Write
Offset: 0x008 + n*0x040
Reset Value: 0x00000000
• TCV: Transfer Counter Value
Number of data items to be transferred by the PDCA. TCV must be programmed with the total number of transfers to be made.
During transfer, TCV contains the number of remaining transfers to be done.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
TCV[15:8]
76543210
TCV[7:0]
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7.7.8 Memory Address Reload Register
Name: MARR
Access Type: Read/Write
Offset: 0x00C + n*0x040
Reset Value: 0x00000000
• MARV: Memory Address Reload Value
Reload Value for the MAR register. This value will be loaded into MAR when TCR reaches zero if the TCRR register has a nonzero
value.
31 30 29 28 27 26 25 24
MARV[31:24]
23 22 21 20 19 18 17 16
MARV[23:16]
15 14 13 12 11 10 9 8
MARV[15:8]
76543210
MARV[7:0]
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7.7.9 Transfer Counter Reload Register
Name: TCRR
Access Type: Read/Write
Offset: 0x010 + n*0x040
Reset Value: 0x00000000
• TCRV: Transfer Counter Reload Value
Reload value for the TCR register. When TCR reaches zero, it will be reloaded with TCRV if TCRV has a positive value. If TCRV
is zero, no more transfers will be performed for the channel. When TCR is reloaded, the TCRR register is cleared.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
TCRV[15:8]
76543210
TCRV[7:0]
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7.7.10 Control Register
Name: CR
Access Type: Write-only
Offset: 0x014 + n*0x040
Reset Value: 0x00000000
• ECLR: Transfer Error Clear
Writing a zero to this bit has no effect.
Writing a one to this bit will clear the Transfer Error bit in the Status Register (SR.TERR). Clearing the SR.TERR bit will allow the
channel to transmit data. The memory address must first be set to point to a valid location.
• TDIS: Transfer Disable
Writing a zero to this bit has no effect.
Writing a one to this bit will disable transfer for the DMA channel.
• TEN: Transfer Enable
Writing a zero to this bit has no effect.
Writing a one to this bit will enable transfer for the DMA channel.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - - ECLR
76543210
- - - - - - TDIS TEN
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7.7.11 Mode Register
Name: MR
Access Type: Read/Write
Offset: 0x018 + n*0x040
Reset Value: 0x00000000
• RING: Ring Buffer
0:The Ring buffer functionality is disabled.
1:The Ring buffer functionality is enabled. When enabled, the reload registers, MARR and TCRR will not be cleared after reload.
• ETRIG: Event Trigger
0:Start transfer when the peripheral selected in Peripheral Select Register (PSR) requests a transfer.
1:Start transfer only when or after a peripheral event is received.
• SIZE: Size of Transfer
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - RING ETRIG SIZE
Table 7-5. Size of Transfer
SIZE Size of Transfer
0 Byte
1 Halfword
2 Word
3 Reserved
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7.7.12 Status Register
Name: SR
Access Type: Read-only
Offset: 0x01C + n*0x040
Reset Value: 0x00000000
• TEN: Transfer Enabled
This bit is cleared when the TDIS bit in CR is written to one.
This bit is set when the TEN bit in CR is written to one.
0: Transfer is disabled for the DMA channel.
1: Transfer is enabled for the DMA channel.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - TEN
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7.7.13 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x020 + n*0x040
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TERR TRC RCZ
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7.7.14 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x024 + n*0x040
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TERR TRC RCZ
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7.7.15 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x028 + n*0x040
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TERR TRC RCZ
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7.7.16 Interrupt Status Register
Name: ISR
Access Type: Read-only
Offset: 0x02C + n*0x040
Reset Value: 0x00000000
• TERR: Transfer Error
This bit is cleared when no transfer errors have occurred since the last write to CR.ECLR.
This bit is set when one or more transfer errors has occurred since reset or the last write to CR.ECLR.
• TRC: Transfer Complete
This bit is cleared when the TCR and/or the TCRR holds a non-zero value.
This bit is set when both the TCR and the TCRR are zero.
• RCZ: Reload Counter Zero
This bit is cleared when the TCRR holds a non-zero value.
This bit is set when TCRR is zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TERR TRC RCZ
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7.7.17 Performance Control Register
Name: PCONTROL
Access Type: Read/Write
Offset: 0x800
Reset Value: 0x00000000
• MON1CH: Performance Monitor Channel 1
• MON0CH: Performance Monitor Channel 0
The PDCA channel number to monitor with counter n
Due to performance monitor hardware resource sharing, the two performance monitor channels should NOT be programmed to
monitor the same PDCA channel. This may result in UNDEFINED monitor behavior.
• CH1RES: Performance Channel 1 Counter Reset
Writing a zero to this bit has no effect.
Writing a one to this bit will reset the counter in the channel specified in MON1CH.
This bit always reads as zero.
• CH0RES: Performance Channel 0 Counter Reset
Writing a zero to this bit has no effect.
Writing a one to this bit will reset the counter in the channel specified in MON0CH.
This bit always reads as zero.
• CH1OF: Channel 1 Overflow Freeze
0: The performance channel registers are reset if DATA or STALL overflows.
1: All performance channel registers are frozen just before DATA or STALL overflows.
• CH1OF: Channel 0 Overflow Freeze
0: The performance channel registers are reset if DATA or STALL overflows.
1: All performance channel registers are frozen just before DATA or STALL overflows.
• CH1EN: Performance Channel 1 Enable
0: Performance channel 1 is disabled.
1: Performance channel 1 is enabled.
• CH0EN: Performance Channel 0 Enable
0: Performance channel 0 is disabled.
1: Performance channel 0 is enabled.
31 30 29 28 27 26 25 24
- - MON1CH
23 22 21 20 19 18 17 16
- - MON0CH
15 14 13 12 11 10 9 8
- - - - - - CH1RES CH0RES
76543210
- - CH1OF CH0OF - - CH1EN CH0EN
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7.7.18 Performance Channel 0 Read Data Cycles
Name: PRDATA0
Access Type: Read-only
Offset: 0x804
Reset Value: 0x00000000
• DATA: Data Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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7.7.19 Performance Channel 0 Read Stall Cycles
Name: PRSTALL0
Access Type: Read-only
Offset: 0x808
Reset Value: 0x00000000
• STALL: Stall Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
STALL[31:24]
23 22 21 20 19 18 17 16
STALL[23:16]
15 14 13 12 11 10 9 8
STALL[15:8]
76543210
STALL[7:0]
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7.7.20 Performance Channel 0 Read Max Latency
Name: PRLAT0
Access Type: Read/Write
Offset: 0x80C
Reset Value: 0x00000000
• LAT: Maximum Transfer Initiation Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
This counter is saturating. The register is reset only when PCONTROL.CH0RES is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
LAT[15:8]
76543210
LAT[7:0]
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7.7.21 Performance Channel 0 Write Data Cycles
Name: PWDATA0
Access Type: Read-only
Offset: 0x810
Reset Value: 0x00000000
• DATA: Data Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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7.7.22 Performance Channel 0 Write Stall Cycles
Name: PWSTALL0
Access Type: Read-only
Offset: 0x814
Reset Value: 0x00000000
• STALL: Stall Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
STALL[31:24]
23 22 21 20 19 18 17 16
STALL[23:16]
15 14 13 12 11 10 9 8
STALL[15:8]
76543210
STALL[7:0]
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7.7.23 Performance Channel 0 Write Max Latency
Name: PWLAT0
Access Type: Read/Write
Offset: 0x818
Reset Value: 0x00000000
• LAT: Maximum Transfer Initiation Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
This counter is saturating. The register is reset only when PCONTROL.CH0RES is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
LAT[15:8]
76543210
LAT[7:0]
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7.7.24 Performance Channel 1 Read Data Cycles
Name: PRDATA1
Access Type: Read-only
Offset: 0x81C
Reset Value: 0x00000000
• DATA: Data Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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7.7.25 Performance Channel 1 Read Stall Cycles
Name: PRSTALL1
Access Type: Read-only
Offset: 0x820
Reset Value: 0x00000000
• STALL: Stall Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
STALL[31:24]
23 22 21 20 19 18 17 16
STALL[23:16]
15 14 13 12 11 10 9 8
STALL[15:8]
76543210
STALL[7:0]
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7.7.26 Performance Channel 1 Read Max Latency
Name: PRLAT1
Access Type: Read/Write
Offset: 0x824
Reset Value: 0x00000000
• LAT: Maximum Transfer Initiation Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
This counter is saturating. The register is reset only when PCONTROL.CH1RES is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
LAT[15:8]
76543210
LAT[7:0]
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7.7.27 Performance Channel 1 Write Data Cycles
Name: PWDATA1
Access Type: Read-only
Offset: 0x828
Reset Value: 0x00000000
• DATA: Data Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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7.7.28 Performance Channel 1 Write Stall Cycles
Name: PWSTALL1
Access Type: Read-only
Offset: 0x82C
Reset Value: 0x00000000
• STALL: Stall Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
31 30 29 28 27 26 25 24
STALL[31:24]
23 22 21 20 19 18 17 16
STALL[23:16]
15 14 13 12 11 10 9 8
STALL[15:8]
76543210
STALL[7:0]
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7.7.29 Performance Channel 1 Write Max Latency
Name: PWLAT1
Access Type: Read/Write
Offset: 0x830
Reset Value: 0x00000000
• LAT: Maximum Transfer Initiation Cycles Counted Since Last Reset
Clock cycles are counted using the CLK_PDCA_HSB clock
This counter is saturating. The register is reset only when PCONTROL.CH1RES is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
LAT[15:8]
76543210
LAT[7:0]
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7.7.30 PDCA Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x834
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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7.8 Module Configuration
The specific configuration for each PDCA instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
The PDCA and the peripheral modules communicate through a set of handshake signals. The
following table defines the valid settings for the Peripheral Identifier (PID) in the PDCA Peripheral
Select Register (PSR). The direction is specified as observed from the memory, so RX
means transfers from peripheral to memory, and TX means from memory to peripheral.
Table 7-6. PDCA Configuration
Feature PDCA
Number of channels 12
Number of performance monitors 1
Table 7-7. PDCA Clocks
Clock Name Description
CLK_PDCA_HSB Clock for the PDCA HSB interface
CLK_PDCA_PB Clock for the PDCA PB interface
Table 7-8. Register Reset Values
Register Reset Value
PSR CH 0 0
PSR CH 1 1
PSR CH 2 2
PSR CH 3 3
PSR CH 4 4
PSR CH 5 5
PSR CH 6 6
PSR CH 7 7
PSR CH 8 8
PSR CH 9 9
PSR CH 10 10
PSR CH 11 11
VERSION 123
Table 7-9. Peripheral Identity Values
PID Direction Peripheral Instance Peripheral Register
0 RX USART0 RHR
1 RX USART1 RHR
2 RX USART2 RHR
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3 RX USART3 RHR
4 RX SPI RDR
5 RX TWIM0 RHR
6 RX TWIM1 RHR
7 RX TWIS0 RHR
8 RX TWIS1 RHR
9 RX ADCIFB LCDR
10 RX AW RHR
11 RX CAT ACOUNT
12 TX USART0 THR
13 TX USART1 THR
14 TX USART2 THR
15 TX USART3 THR
16 TX SPI TDR
17 TX TWIM0 THR
18 TX TWIM1 THR
19 TX TWIS0 THR
20 TX TWIS1 THR
21 TX AW THR
22 TX CAT MBLEN
23 TX ABDACB SDR0
24 TX ABDACB SDR1
25 RX IISC RHR (CH0)
26 RX IISC RHR (CH1)
27 TX IISC THR (CH0)
28 TX IISC THR (CH1)
29 RX CAT DMATSR
30 TX CAT DMATSW
Table 7-9. Peripheral Identity Values
PID Direction Peripheral Instance Peripheral Register
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8. USB Interface (USBC)
Rev: 2.0.0.15
8.1 Features
• Compatible with the USB 2.0 specification
• Supports full (12Mbit/s) and low (1.5Mbit/s) speed communication
• Seven physical pipes/endpoints in ping-pong mode
• Flexible pipe/endpoint configuration and reallocation of data buffers in embedded RAM
• Up to two memory banks per pipe/endpoint
• Built-in DMA with multi-packet support through ping-pong mode
• On-chip transceivers with built-in pull-ups and pull-downs
8.2 Overview
The Universal Serial Bus interface (USBC) module complies with the Universal Serial Bus (USB)
2.0 specification.
Each pipe/endpoint can be configured into one of several transfer types. It can be associated
with one or more memory banks (located inside the embedded system or CPU RAM) used to
store the current data payload. If two banks are used (“ping-pong” mode), then one bank is read
or written by the CPU (or any other HSB master) while the other is read or written by the USBC
core.
Table 8-1 describes the hardware configuration of the USBC module.
8.3 Block Diagram
The USBC interfaces a USB link with a data flow stored in the embedded ram (CPU or HSB).
The USBC requires a 48MHz ± 0.25% reference clock, which is the USB generic clock. For
more details see ”Clocks” on page 84. The 48MHz clock is used to generate either a 12MHz fullspeed
or a 1.5MHz low-speed bit clock from the received USB differential data, and to transmit
data according to full- or low-speed USB device tolerances. Clock recovery is achieved by a digital
phase-locked loop (a DPLL, not represented) in the USBC module, which complies with the
USB jitter specifications.
The USBC module consists of:
• HSB master interface
Table 8-1. Description of USB pipes/endpoints
pipe/endpoint Mnemonic Max. size
Number of
available banks Type
0 PEP0 1023 bytes 1 Control/Isochronous/Bulk/Interrupt
1 PEP1 1023 bytes 2 Control/Isochronous/Bulk/Interrupt
2 PEP2 1023 bytes 2 Control/Isochronous/Bulk/Interrupt
... ... ... ... ...
6 PEP6 1023 bytes 2 Control/Isochronous/Bulk/Interrupt
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• User interface
• USB Core
• Transceiver pads
Figure 8-1. USBC Block Diagram
Note: in the block diagram is symbolic, it is mapped to a GPIO pin (See Section “8.5.1” on page 84.).
The VBUS detection (rising edge detection on the GPIO pin) should be handled by software.
Interrupt
Controller
USB interrupts
DM
USB_VBUS (1)
USB
DP
User interface
SCIF GCLK_USBC @ 48 MHz
PB
USB 2.0
Core
USB clock
domain
System clock
domain
HSB
HSB Master
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8.4 I/O Lines Description
Table 8-2. I/O Lines Description
PIn Name Pin Description Type Active Level
DM Data -: Differential Data Line - Port Input/Output
DP Data +: Differential Data Line + Port Input/Output
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8.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
8.5.1 I/O Lines
The USBC pins may be multiplexed with the I/O Controller lines. The user must first configure
the I/O Controller to assign the desired USBC pins to their peripheral functions.
The USB VBUS line should be connected to a GPIO pin and the user should monitor this with
software.
8.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the USBC, the USBC will stop functioning
and resume operation after the system wakes up from sleep mode.
8.5.3 Clocks
The USBC has two bus clocks connected: One High Speed Bus clock (CLK_USBC_HSB) and
one Peripheral Bus clock (CLK_USBC_PB). These clocks are generated by the Power Manager.
Both clocks are enabled at reset, and can be disabled by the Power Manager. It is
recommended to disable the USBC before disabling the clocks, to avoid freezing the USBC in
an undefined state.
The 48MHz USB clock is generated by a dedicated generic clock from the SCIF module. Before
using the USB, the user must ensure that the USB generic clock (GCLK_USBC) is enabled at
48MHz in the SCIF module.
8.5.4 Interrupts
The USBC interrupt request line is connected to the interrupt controller. Using the USBC interrupt
requires the interrupt controller to be programmed first.
The USBC asynchronous interrupt can wake the CPU from any sleep mode:
• The Wakeup Interrupt (WAKEUP)
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8.6 Functional Description
8.6.1 USB General Operation
8.6.1.1 Initialization
After a hardware reset, the USBC is in the Reset state. In this state:
• The module is disabled. The USBC Enable bit in the General Control register
(USBCON.USBE) is reset.
• The module clock is stopped in order to minimize power consumption. The Freeze USB Clock
bit in USBCON (USBCON.FRZCLK) is set.
• The USB pad is in suspend mode.
• The internal states and registers of the device are reset.
• The Freeze USB Clock (FRZCLK), USBC Enable (USBE), in USBCON and the Low-Speed
mode bit in the Device General Control register (UDCON.LS) can be written to by software,
so that the user can configure pads and speed before enabling the module. These values are
only taken into account once the module has been enabled and unfrozen.
After writing a one to USBCON.USBE, the USBC enters device mode in idle state.
Refer to Section 8.6.2 for the basic operation of the device mode.
The USBC can be disabled at any time by writing a zero to USBCON.USBE, this acts as a hardware
reset, except that the FRZCLK,bit in USBCON, and the LS bits in UDCON are not reset.
8.6.1.2 Interrupts
One interrupt vector is assigned to the USBC.
See Section 8.6.2.18 for further details about device interrupts.
See Section 8.5.4 for asynchronous interrupts.
8.6.1.3 Frozen clock
When the USB clock is frozen, it is still possible to access the following bits: FRZCLK, and USBE
in the USBCON register, and LS in the UDCON register.
When FRZCLK is set, only the asynchronous interrupt can trigger a USB interrupt (see Section
8.5.4).
8.6.1.4 Speed control
• Device mode
When the USBC interface is in device mode, the speed selection is done by the UDCON.LS bit,
connecting an internal pull-up resistor to either DP (full-speed mode) or DM (low-speed mode).
The LS bit shall be written before attaching the device, which can be simulated by clearing the
UDCON.DETACH bit.
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Figure 8-2. Speed Selection in device mode
8.6.1.5 Data management
Endpoints and pipe buffers can be allocated anywhere in the embedded memory (CPU RAM or
HSB RAM).
See ”RAM management” on page 90.
8.6.1.6 Pad Suspend
Figure 8-3 illustrates the behavior of the USB pad in device mode.
Figure 8-3. Pad Behavior
• In Idle state, the pad is in low power consumption mode.
• In Active state, the pad is working.
Figure 8-4 illustrates the pad events leading to a PAD state change.
RPU
UDCON.DETACH
DP
DM
UDCON.LS
VBUS
Idle
Active
USBE = 1
& DETACH = 0
& Suspend
USBE = 0
| DETACH = 1
| Suspend
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Figure 8-4. Pad events
The Suspend Interrupt bit in the Device Global Interrupt register (UDINT.SUSP) is set and the
Wakeup Interrupt (UDINT.WAKEUP) bit is cleared when a USB Suspend state has been
detected on the USB bus. This event automatically puts the USB pad in the Idle state. The
detection of a non-idle event sets WAKEUP, clears SUSP, and wakes the USB pad.
The pad goes to the Idle state if the module is disabled or if UDCON.DETACH is written to one.
It returns to the Active state when USBCON.USBE is written to one and DETACH is written to
zero.
SUSP Suspend detected Cleared on Wakeup
WAKEUP Wakeup detected Cleared by software to acknowledge the interrupt
PAD state
Active Idle Active
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8.6.2 USBC Device Mode Operation
8.6.2.1 Device Enabling
In device mode, the USBC supports full- and low-speed data transfers.
Including the default control endpoint, a total of seven endpoints are provided. They can be configured
as isochronous, bulk or interrupt types, as described in Table 8-1 on page 81
After a hardware reset, the USBC device mode is in the reset state (see Section 8.6.1.1). In this
state, the endpoint banks are disabled and neither DP nor DM are pulled up (DETACH is one).
DP or DM will be pulled up according to the selected speed as soon as the DETACH bit is written
to zero. See “Device mode” for further details.
When the USBC is enabled (USBE is one) in device mode, it enters the Idle state, minimizing
power consumption. Being in Idle state does not require the USB clocks to be activated.
The USBC device mode can be disabled or reset at any time by disabling the USBC (by writing
a zero to USBE).
8.6.2.2 USB reset
The USB bus reset is initiated by a connected host and managed by hardware.
When a USB reset state is detected on the USB bus, the following operations are performed by
the controller:
• UDCON register is reset except for the DETACH and SPDCONF bits.
• Device Frame Number Register (UDFNUM), Endpoint n Configuration Register (UECFGn),
and Endpoint n Control Register (UECONn) registers are cleared.
• The data toggle sequencing in all the endpoints are cleared.
• At the end of the reset process, the End of Reset (EORST) bit in the UDINT register is set.
8.6.2.3 Endpoint activation
When an endpoint is disabled (UERST.EPENn = 0) the data toggle sequence, Endpoint n Status
Set (UESTAn), and UECONn registers will be reset. The controller ignores all transactions to
this endpoint as long as it is inactive.
To complete an endpoint activation, the user should fill out the endpoint descriptor: see Figure 8-
5 on page 91.
8.6.2.4 Data toggle sequence
In order to respond to a CLEAR_FEATURE USB request without disabling the endpoint, the
user can clear the data toggle sequence by writing a one to the Reset Data Toggle Set bit in the
Endpoint n Control Set register (UECONnSET.RSTDTS)
8.6.2.5 Busy bank enable
In order to make an endpoint bank look busy regardless of its actual state, the user can write a
one to the Busy Bank Enable bit in the Endpoint n Control Register (UECONnSET.BUSY0/1ES).
If a BUSYnE bit is set, any transaction to this bank will be rejected with a NAK reply.
8.6.2.6 Address setup
The USB device address is set up according to the USB protocol.
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• After all kinds of resets, the USB device address is 0.
• The host starts a SETUP transaction with a SET_ADDRESS(addr) request.
• The user writes this address to the USB Address field (UDCON.UADD), and writes a zero to
the Address Enable bit (UDCON.ADDEN), resulting in the address remaining zero.
• The user sends a zero-length IN packet from the control endpoint.
• The user enables the stored USB device address by writing a one to ADDEN.
Once the USB device address is configured, the controller filters the packets to only accept
those targeting the address stored in UADD.
UADD and ADDEN should not be written to simultaneously. They should be written sequentially,
UADD field first.
If UADD or ADDEN is cleared, the default device address 0 is used. UADD and ADDEN are
cleared:
• On a hardware reset.
• When the USBC is disabled (USBE written to zero).
• When a USB reset is detected.
8.6.2.7 Suspend and Wakeup
When an idle USB bus state has been detected for 3 ms, the controller sets the Suspend
(SUSP) interrupt bit in UDINT. In this case, the transceiver is suspended, reducing power
consumption.
To further reduce power consumption it is recommended to freeze the USB clock by writing a
one to the Freeze USB Clock (FRZCLK) bit in USBCON when the USB bus is in suspend mode.
The MCU can also enter the idle or frozen sleep mode to further lower power consumption.
To recover from the suspend mode, the user shall wait for the Wakeup (WAKEUP) interrupt bit,
which is set when a non-idle event is detected, and then write a zero to FRZCLK.
As the WAKEUP interrupt bit in UDINT is set when a non-idle event is detected, it can occur
regardless of whether the controller is in the suspend mode or not. The SUSP and WAKEUP
interrupts are thus independent of each other except for that one bit is cleared when the other is
set.
8.6.2.8 Detach
The reset value of the DETACH bit located in the UDCON register, is one.
It is possible to initiate a device re-enumeration simply by writing a one and then a zero to
DETACH.
DETACH acts on the pull-up connections of the DP and DM pads. See “Device mode” for further
details.
8.6.2.9 Remote wakeup
The remote wakeup request (also known as upstream resume) is the only request the device
may send on its own initiative. This should be preceded by a DEVICE_REMOTE_WAKEUP
request from the host.
• First, the USBC must have detected a “Suspend” state on the bus, i.e. the remote wakeup
request can only be sent after a SUSP interrupt has been set.
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• The user may then write a one to the remote wakeup (RMWKUP) bit in UDCON to send an
Upstream Resume to the host initiating the wakeup. This will automatically be done by the
controller after 5ms of inactivity on the USB bus.
• When the controller sends the Upstream Resume, the Upstream Resume (UPRSM) interrupt
is set and SUSP is cleared.
• RMWKUP is cleared at the end of the transmitting Upstream Resume.
• In case of a rebroadcast resume initiated by the host, the End of Resume (EORSM) interrupt
is set when the rebroadcast resume is completed.
8.6.2.10 RAM management
Endpoint data can be physically allocated anywhere in the embedded RAM. The USBC controller
accesses these endpoints directly through the HSB master (built-in DMA).
The USBC controller reads the USBC descriptors to know where each endpoint is located. The
base address of the USBC descriptor (UDESC.UDESCA) needs to be written by the user. The
descriptors can also be allocated anywhere in the embedded RAM.
Before using an endpoint, the user should setup the endpoint address for each bank. Depending
on the direction, the type, and the packet-mode (single or multi-packet), the user should also initialize
the endpoint packet size, and the endpoint control and status fields, so that the USBC
controller does not compute random values from the RAM.
When using an endpoint the user should read the UESTAX.CURRBK field to know which bank
is currently being processed.
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Figure 8-5. Memory organization
Each descriptor of an endpoint n consists of four words.
• The address of the endpoint and the bank used (EPn_ADDR_BK0/1).
• The packet size information for the endpoint and bank (EPn_PCKSIZE_BK0/1):
Table 8-3. EPn_PCKSIZE_BK0/1 structure
– AUTO_ZLP: Auto zero length packet, see ”Multi packet mode for IN endpoints” on
page 96.
– MULTI_PACKET_SIZE: see ”Multi packet mode and single packet mode.” on page
93.
– BYTE_COUNT: see ”Multi packet mode and single packet mode.” on page 93.
31 30:16 15 14:0
AUTO_ZLP MULTI_PACKET_SIZE - BYTE_COUNT
EPn BK0
EP0_CTR_STA_BK0
E P 0 _ P C K S IZ E _ B K 0
EP0_ADDR_BK0 UDESCA
Growing Memory Addresses
Descriptor EP0
R e se rve d
EP0_CTR _STA_BK1
E P 0 _ P C K S IZ E _ B K 1
EP0_ADDR_BK1
R e se rve d
Bank0
Bank1
+0x000
+0x004
+0x008
+0x00C
+0x010
+0x014
+0x018
+0x01C
EP1_CTR_STA_BK0
E P 1 _ P C K S IZ E _ B K 0
EP1_ADDR_BK0
Descriptor EP1
R e se rve d
EP1_CTR _STA_BK1
E P 1 _ P C K S IZ E _ B K 1
EP1_ADDR_BK1
R e se rve d
Bank0
Bank1
+0x020
+0x024
+0x028
+0x02C
+0x030
+0x034
+0x038
+0x03C
EPn_CTR_STA_BK0
E P n _ P C K S IZ E _ B K 0
EPn_ADDR_BK0
R e se rve d
EPn_CTR _STA_BK1
E P n _ P C K S IZ E _ B K 1
EPn_ADDR_BK1
R e se rve d
Bank0
Bank1
Descriptor EPn
EPn BK1
U S B d e s c rip to rs
U S B B u ffe rs
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• The control and status fields for the endpoint and bank (EPn_CTR_STA_BK0/1):
Table 8-4. EPn_CTR_STA_BK0/1 structure
– UNDERF: Underflow status for isochronous IN transfer. See ”Data flow error” on
page 99.
– OVERF: Overflow status for isochronous OUT transfer. See ”Data flow error” on
page 99.
– CRCERR: CRC error status for isochronous OUT transfer. See ”CRC error” on page
99.
– STALLRQ_NEXT: Stall request for the next transfer. See ”STALL request” on page
92.
8.6.2.11 STALL request
For each endpoint, the STALL management is performed using:
• The STALL Request (STALLRQ) bit in UECONn is set to initiate a STALL request.
• The STALLed Interrupt (STALLEDI) bit in UESTAn is set when a STALL handshake has been
sent.
To answer requests with a STALL handshake, STALLRQ has to be set by writing a one to the
STALL Request Set (STALLRQS) bit. All following requests will be discarded (RXOUTI, etc. will
not be set) and handshaked with a STALL until the STALLRQ bit is cleared, by receiving a new
SETUP packet (for control endpoints) or by writing a one to the STALL Request Clear (STALLRQC)
bit.
Each time a STALL handshake is sent, the STALLEDI bit is set by the USBC and the EPnINT
interrupt is set.
The user can use the descriptor to manage STALL requests. The USBC controller reads the
EPn_CTR_STA_BK0/1.STALLRQ_NEXT bit after successful transactions and if it is one the
USBC controller will set UECON.STALLRQ. The STALL_NEXT bit will be cleared upon receiving
a SETUP transaction and the USBC controller will then clear the STALLRQ bit.
• Special considerations for control endpoints
If a SETUP packet is received at a control endpoint where a STALL request is active, the
Received SETUP Interrupt (RXSTPI) bit in UESTAn is set, and the STALLRQ and STALLEDI
bits are cleared. It allows the SETUP to be always ACKed as required by the USB standard.
This management simplifies the enumeration process management. If a command is not supported
or contains an error, the user requests a STALL and can return to the main task, waiting
for the next SETUP request.
• STALL handshake and retry mechanism
The retry mechanism has priority over the STALL handshake. A STALL handshake is sent if the
STALLRQ bit is set and if there is no retry required.
31:19 18 17 16 15:1 0
Status elements Control elements
- UNDERF OVERF CRCERR - STALLRQ_NEXT
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8.6.2.12 Multi packet mode and single packet mode.
Single packet mode is the default mode where one USB packet is managed per bank.
The multi-packet mode allows the user to manage data exceeding the maximum endpoint size
(UECFGn.EPSIZE) for an endpoint bank across multiple packets without software intervention.
This mode can also be coupled with the ping-pong mode.
• For an OUT endpoint, the EPn_PCKSIZE_BK0/1.MULTI_PACKET_SIZE field should be
configured correctly to enable the multi-packet mode. See ”Multi packet mode for OUT
endpoints” on page 98. For single packet mode, the MULTI_PACKET_SIZE should be
initialized to 0.
• For an IN endpoint, the EPn_PCKSIZE_BK0/1.BYTE_COUNT field should be configured
correctly to enable the multi-packet mode. See”Multi packet mode for IN endpoints” on page
96. For single packet mode, the BYTE_COUNT should be less than EPSIZE.
8.6.2.13 Management of control endpoints
• Overview
A SETUP request is always ACKed. When a new SETUP packet is received, the RXSTPI is set,
but not the Received OUT Data Interrupt (RXOUTI) bit.
The FIFO Control (FIFOCON) bit in UECONn is irrelevant for control endpoints. The user should
therefore never use it for these endpoints. When read, this value is always zero.
Control endpoints are managed using:
• The RXSTPI bit: is set when a new SETUP packet is received. This has to be cleared by
firmware in order to acknowledge the packet and to free the bank.
• The RXOUTI bit: is set when a new OUT packet is received. This has to be cleared by
firmware in order to acknowledge the packet and to free the bank.
• The Transmitted IN Data Interrupt (TXINI) bit: is set when the current bank is ready to accept
a new IN packet. This has to be cleared by firmware in order to send the packet.
• Control write
Figure 8-6 on page 94 shows a control write transaction. During the status stage, the controller
will not necessarily send a NAK on the first IN token:
• If the user knows the exact number of descriptor bytes that will be read, the status stage can
be predicted, and a zero-length packet can be sent after the next IN token.
• Alternatively the bytes can be read until the NAKed IN Interrupt (NAKINI) is triggered,
notifying that all bytes are sent by the host and that the transaction is now in the status stage.
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Figure 8-6. Control Write
• Control read
Figure 8-7 on page 94 shows a control read transaction. The USBC has to manage the simultaneous
write requests from the CPU and USB host.
Figure 8-7. Control Read
A NAK handshake is always generated as the first status stage command. The UESTAn.NAKINI
bit is set. It allows the user to know that the host aborts the IN data stage. As a consequence,
the user should stop processing the IN data stage and should prepare to receive the OUT status
stage by checking the UESTAn.RXOUTI bit.
The OUT retry is always ACKed. This OUT reception sets RXOUTI. Handle this with the following
software algorithm:
// process the IN data stage
set TXINI
wait for RXOUTI (rising) OR TXINI (falling)
if RXOUTI is high, then process the OUT status stage
if TXINI is low, then return to process the IN data stage
Once the OUT status stage has been received, the USBC waits for a SETUP request. The
SETUP request has priority over all other requests and will be ACKed.
SETUP
RXSTPI
RXOUTI
TXINI
USB Bus
HW SW
OUT
HW SW
OUT
HW SW
IN IN
NAK
SW
SETUP STATUS DATA
SETUP
RXSTPI
RXOUTI
TXINI
USB Bus
HW SW
IN
HW SW
IN OUT OUT
NAK
SW
SW
HW
Wr Enable
HOST
Wr Enable
CPU
SETUP STATUS DATA
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8.6.2.14 Management of IN endpoints
• Overview
IN packets are sent by the USBC device controller upon IN requests from the host.
The endpoint and its descriptor in RAM must be pre configured (see section ”RAM management”
on page 90 for more details).
When the current bank is clear, the TXINI and FIFO Control (UECONn.FIFOCON) bits will be set
simultaneously. This triggers an EPnINT interrupt if the Transmitted IN Data Interrupt Enable
(TXINE) bit in UECONn is one.
TXINI shall be cleared by software (by writing a one to the Transmitted IN Data Interrupt Enable
Clear bit in the Endpoint n Control Clear register (UECONnCLR.TXINIC)) to acknowledge the
interrupt. This has no effect on the endpoint FIFO.
The user writes the IN data to the bank referenced by the EPn descriptor and allows the USBC
to send the data by writing a one to the FIFO Control Clear (UECONnCLR.FIFOCONC) bit. This
will also cause a switch to the next bank if the IN endpoint is composed of multiple banks. The
TXINI and FIFOCON bits will be updated accordingly.
TXINI should always be cleared before clearing FIFOCON to avoid missing an TXINI event.
Figure 8-8. Example of an IN endpoint with one data bank
Figure 8-9. Example of an IN endpoint with two data banks
IN DATA
(bank 0) ACK
TXINI
FIFOCON
HW
write data to CPU
BANK 0
SW
SW SW
SW
IN
NAK
write data to CPU
BANK 0
IN DATA
(bank 0) ACK
TXINI
FIFOCON write data to CPU
BANK 0
SW
SW SW
SW
IN DATA
(bank 1) ACK
write data to CPU
BANK 1
SW
HW
write data to CPU
BANK0
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• Detailed description
The data is written according to this sequence:
• When the bank is empty, TXINI and FIFOCON are set, which triggers an EPnINT interrupt if
TXINE is one.
• The user acknowledges the interrupt by clearing TXINI.
• The user reads the UESTAX.CURRBK field to see which the current bank is.
• The user writes the data to the current bank, located in RAM as described by its descriptor:
EPn_ADDR_BK0/1.
• The user should write the size of the IN packet into the USB descriptor:
EPn_PCKSIZE_BK0/1.BYTE_COUNT.
• The user allows the controller to send the bank contents and switches to the next bank (if
any) by clearing FIFOCON.
If the endpoint uses several banks, the current one can be written while the previous one is
being read by the host. When the user clears FIFOCON, the next current bank may already be
clear and TXINI is set immediately.
An “Abort” stage can be produced when a zero-length OUT packet is received during an IN
stage of a control or isochronous IN transaction. The Kill IN Bank (KILLBK) bit in UECONn is
used to kill the last written bank. The best way to manage this abort is to apply the algorithm represented
on Figure 8-10 on page 96. See ”Endpoint n Control Register” on page 130 for more
details about the KILLBK bit.
Figure 8-10. Abort Algorithm
• Multi packet mode for IN endpoints
In multi packet mode, the user can prepare n USB packets in the bank to be sent on a multiple
IN transaction. The packet sizes will equal UECFGn.EPSIZE unless the AUTO_ZLP option is
Endpoint
Abort
Abort Done
Abort is based on the fact
that no bank is busy, i.e.,
that nothing has to be sent
Disable the TXINI interrupt.
EPRSTn = 1
NBUSYBK
== 0?
Yes
TXINEC = 1
No
KILLBKS = 1
KILLBK
Yes == 1?
Kill the last written bank.
Wait for the end of the
procedure
No
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set, or if the total byte count is not an integral multiple of EPSIZE, whereby the last packet
should be short.
To enable the multi packet mode, the user should configure the endpoint descriptor
(EPn_PCKSIZE_BK0/1.BYTE_COUNT) to the total size of the multi packet, which should be
larger than the endpoint size (EPSIZE).
Since the EPn_PCKSIZE_BK0/1.MULTI_PACKET_SIZE is incremented (by the transmitted
packet size) after each successful transaction, it should be set to zero when setting up a new
multi packet transfer.
The EPn_PCKSIZE_BK0/1.MULTI_PACKET_SIZE is cleared by hardware when all the bank
contents have been sent. The bank is considered as ready and the TX_IN flag is set when:
• A short packet (smaller than EPSIZE) has been transmitted.
• A packet has been successfully transmitted, the updated MULTI_PACKET_SIZE equals the
BYTE_COUNT, and the AUTO_ZLP field is not set.
• An extra zero length packet has been automatically sent for the last transfer of the current
bank, if BYTE_COUNT is a multiple of EPSIZE and AUTO_ZLP is set.
8.6.2.15 Management of OUT endpoints
• Overview
The endpoint and its descriptor in RAM must be pre configured, see section ”RAM management”
on page 90 for more details.
When the current bank is full, the RXOUTI and FIFO Control (UECONn.FIFOCON) bits will be
set simultaneously. This triggers an EPnINT interrupt if the Received OUT Data Interrupt Enable
(RXOUTE) bit in UECONn is one.
RXOUTI shall be cleared by software (by writing a one to the Received OUT Data Interrupt Clear
(RXOUTIC) bit) to acknowledge the interrupt. This has no effect on the endpoint FIFO.
The user reads the OUT data from the RAM and clears the FIFOCON bit to free the bank. This
will also cause a switch to the next bank if the OUT endpoint is composed of multiple banks.
RXOUTI should always be cleared before clearing FIFOCON to avoid missing an RXOUTI
event.
Figure 8-11. Example of an OUT endpoint with one data bank
OUT DATA
(bank 0) ACK
RXOUTI
FIFOCON
HW
OUT DATA
(bank 0) ACK
HW
SW
SW
SW
read data from CPU
BANK 0
read data from CPU
BANK 0
NAK
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Figure 8-12. Example of an OUT endpoint with two data banks
• Detailed description
Before using the OUT endpoint, one should properly initialize its descriptor for each bank. See
Figure 8-5 on page 91.
The data is read, according to this sequence:
• When the bank is full, RXOUTI and FIFOCON are set, which triggers an EPnINT interrupt if
RXOUTE is one.
• The user acknowledges the interrupt by writing a one to RXOUTIC in order to clear RXOUTI.
• The user reads the UESTAX.CURRBK field to know the current bank number.
• The user reads the byte count of the current bank from the descriptor in RAM
(EPn_PCKSIZE_BK0/1.BYTE_COUNT) to know how many bytes to read.
• The user reads the data in the current bank, located in RAM as described by its descriptor:
EPn_ADDR_BK0/1.
• The user frees the bank and switches to the next bank (if any) by clearing FIFOCON.
If the endpoint uses several banks, the current one can be read while the next is being written by
the host. When the user clears FIFOCON, the following bank may already be ready and RXOUTI
will be immediately set.
• Multi packet mode for OUT endpoints
In multi packet mode, the user can extend the size of the bank allowing the storage of n USB
packets in the bank.
To enable the multi packet mode, the user should configure the endpoint descriptor
(EPn_PCKSIZE_BK0/1.MULTI_PACKET_SIZE) to match the size of the multi packet.This value
should be a multiple of the endpoint size (UECFGn.EPSIZE).
Since the EPn_PCKSIZE_BK0/1.BYTE_COUNT is incremented (by the received packet size)
after each successful transaction, it should be set to zero when setting up a new multi packet
transfer.
As for single packet mode, the number of received data bytes is stored in the BYTE_CNT field.
The bank is considered as “valid” and the RX_OUT flag is set when:
OUT DATA
(bank 0)
ACK
RXOUTI
FIFOCON
HW
OUT DATA
(bank 1) ACK
SW
read data from CPU SW
BANK 0
HW
SW
read data from CPU
BANK 1
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• A packet has been successfully received and the updated BYTE_COUNT equals the
MULTI_PACKET_SIZE.
• A short packet (smaller than EPSIZE) has been received.
8.6.2.16 Data flow error
This error exists only for isochronous IN/OUT endpoints. It sets the Errorflow Interrupt
(ERRORFI) bit in UESTAn, which triggers an EPnINT interrupt if the Errorflow Interrupt Enable
(ERRORFE) bit is one. The user can check the EPn_CTR_STA_BK0/1.UNDERF and OVERF
bits in the endpoint descriptor to see which current bank has been affected.
• An underflow can occur during IN stage if the host attempts to read from an empty bank. A
zero-length packet is then automatically sent by the USBC. The endpoint descriptor
EPn_CTR_STA_BK0/1.UNDERF points out the bank from which the IN data should have
originated. If a new successful transaction occurs, the UNDERF bit is overwritten to 0 only if
the UESTAn.ERRORFI is cleared.
• An overflow can occur during the OUT stage if the host tries to send a packet while the bank
is full. Typically this occurs when a CPU is not fast enough. The packet data is not written to
the bank and is lost. The endpoint descriptor EPn_CTR_STA_BK0/1.OVERF points out
which bank the OUT data was destined to. If the UESTAn.ERRORFI bit is cleared and a new
transaction is successful, the OVERF bit will be overwritten to zero.
8.6.2.17 CRC error
This error exists only for isochronous OUT endpoints. It sets the CRC Error Interrupt (CRCERRI)
bit in UESTAn, which triggers an EPnINT interrupt if the CRC Error Interrupt Enable
(CRCERRE) bit is one.
A CRC error can occur during an isochronous OUT stage if the USBC detects a corrupted
received packet. The OUT packet is stored in the bank as if no CRC error had occurred
(RXOUTI is set).
The user can also check the endpoint descriptor to see which current bank is impacted by the
CRC error by reading EPn_CTR_STA_BK0/1.CRCERR.
8.6.2.18 Interrupts
There are two kinds of device interrupts: processing, i.e. their generation is part of the normal
processing, and exception, i.e. errors not related to CPU exceptions.
• Global interrupts
The processing device global interrupts are:
• The Suspend (SUSP) interrupt
• The Start of Frame (SOF) interrupt with no frame number CRC error (the Frame Number
CRC Error (FNCERR) bit in the Device Frame Number (UDFNUM) register is zero)
• The End of Reset (EORST) interrupt
• The Wakeup (WAKEUP) interrupt
• The End of Resume (EORSM) interrupt
• The Upstream Resume (UPRSM) interrupt
• The Endpoint n (EPnINT) interrupt
The exception device global interrupts are:
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• The Start of Frame (SOF) interrupt with a frame number CRC error (FNCERR is one)
• Endpoint interrupts
The processing device endpoint interrupts are:
• The Transmitted IN Data Interrupt (TXINI)
• The Received OUT Data Interrupt (RXOUTI)
• The Received SETUP Interrupt (RXSTPI)
• The Number of Busy Banks (NBUSYBK) interrupt
The exception device endpoint interrupts are:
• The Errorflow Interrupt (ERRORFI)
• The NAKed OUT Interrupt (NAKOUTI)
• The NAKed IN Interrupt (NAKINI)
• The STALLed Interrupt (STALLEDI)
• The CRC Error Interrupt (CRCERRI)
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8.7 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 8-5. USBC Register Memory Map
Offset Register Name Access Reset Value
0x0000 Device General Control Register UDCON Read/Write 0x00000100
0x0004 Device Global Interrupt Register UDINT Read-Only 0x00000000
0x0008 Device Global Interrupt Clear Register UDINTCLR Write-Only 0x00000000
0x000C Device Global Interrupt Set Register UDINTSET Write-Only 0x00000000
0x0010 Device Global Interrupt Enable Register UDINTE Read-Only 0x00000000
0x0014 Device Global Interrupt Enable Clear Register UDINTECLR Write-Only 0x00000000
0x0018 Device Global Interrupt Enable Set Register UDINTESET Write-Only 0x00000000
0x001C Endpoint Enable/Reset Register UERST Read/Write 0x00000000
0x0020 Device Frame Number Register UDFNUM Read-Only 0x00000000
0x0100 + n*4 Endpoint n Configuration Register UECFGn Read/Write 0x00000000
0x0130 + n*4 Endpoint n Status Register UESTAn Read-Only 0x00000100
0x0160 + n*4 Endpoint n Status Clear Register UESTAnCLR Write-Only 0x00000000
0x0190 + n*4 Endpoint n Status Set Register UESTAnSET Write-Only 0x00000000
0x01C0 + n*4 Endpoint n Control Register UECONn Read-Only 0x00000000
0x01F0 + n*4 Endpoint n Control Set Register UECONnSET Write-Only 0x00000000
0x0220 + n*4 Endpoint n Control Clear Register UECONnCLR Write-Only 0x00000000
0x0800 General Control Register USBCON Read/Write 0x00004000
0x0804 General Status Register USBSTA Read-Only 0x00000000
0x0808 General Status Clear Register USBSTACLR Write-Only 0x00000000
0x080C General Status Set Register USBSTASET Write-Only 0x00000000
0x0818 IP Version Register UVERS Read-Only -(1)
0x081C IP Features Register UFEATURES Read-Only -(1)
0x0820 IP PB Address Size Register UADDRSIZE Read-Only -(1)
0x0824 IP Name Register 1 UNAME1 Read-Only -(1)
0x0828 IP Name Register 2 UNAME2 Read-Only -(1)
0x082C USB Finite State Machine Status Register USBFSM Read-Only 0x00000009
0x0830 USB Descriptor address UDESC Read/Write 0x00000000
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8.7.1 USB General Registers
8.7.1.1 General Control Register
Name: USBCON
Access Type: Read/Write
Offset: 0x0800
Reset Value: 0x00004000
• USBE: USBC Enable
Writing a zero to this bit will disable the USBC, USB transceiver, and USB clock inputs. This will over-ride FRZCLK settings but
not affect the value. Unless explicitly stated, all registers will become reset and read-only.
Writing a one to this bit will enable the USBC.
0: The USBC is disabled.
1: The USBC is enabled.
This bit can be written to even if FRZCLK is one.
• FRZCLK: Freeze USB Clock
Writing a zero to this bit will enable USB clock inputs.
Writing a one to this bit will disable USB clock inputs. The resume detection will remain active. Unless explicitly stated, all
registers will become read-only.
0: The clock inputs are enabled.
1: The clock inputs are disabled.
This bit can be written to even if USBE is zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
-- - -- -
15 14 13 12 11 10 9 8
USBE FRZCLK - - - - - -
76543210
--------
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8.7.1.2 General Status Register
Register Name: USBSTA
Access Type: Read-Only
Offset: 0x0804
Reset Value: 0x00000000
• CLKUSABLE: Generic Clock Usable
This bit is cleared when the USB generic clock is not usable.
This bit is set when the USB generic clock (that should be 48 Mhz) is usable.
• SPEED: Speed Status
This field is set according to the controller speed mode.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CLKUSABLE SPEED - - - -
76543210
--------
SPEED Speed Status
00 full-speed mode
01 Reserved
10 low-speed mode
11 Reserved
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8.7.1.3 General Status Clear Register
Register Name: USBSTACLR
Access Type: Write-Only
Offset: 0x0808
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in USBSTA.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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8.7.1.4 General Status Set Register
Register Name: USBSTASET
Access Type: Write-Only
Offset: 0x080C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in USBSTA.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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8.7.1.5 Version Register
Register Name: UVERS
Access Type: Read-Only
Offset: 0x0818
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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8.7.1.6 Features Register
Register Name: UFEATURES
Access Type: Read-Only
Offset: 0x081C
Reset Value: -
• EPTNBRMAX: Maximal Number of pipes/endpoints
This field indicates the number of hardware-implemented pipes/endpoints:
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - EPTNBRMAX
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8.7.1.7 Address Size Register
Register Name: UADDRSIZE
Access Type: Read-Only
Offset: 0x0820
Reset Value: -
• UADDRSIZE: IP PB Address Size
This field indicates the size of the PB address space reserved for the USBC IP interface.
31 30 29 28 27 26 25 24
UADDRSIZE[31:24]
23 22 21 20 19 18 17 16
UADDRSIZE[23:16]
15 14 13 12 11 10 9 8
UADDRSIZE[15:8]
76543210
UADDRSIZE[7:0]
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8.7.1.8 IP Name Register 1
Register Name: UNAME1
Access Type: Read-Only
Offset: 0x0824
Reset Value: -
• UNAME1: IP Name Part One
This field indicates the first part of the ASCII-encoded name of the USBC IP.
31 30 29 28 27 26 25 24
UNAME1[31:24]
23 22 21 20 19 18 17 16
UNAME1[23:16]
15 14 13 12 11 10 9 8
UNAME1[15:8]
76543210
UNAME1[7:0]
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8.7.1.9 IP Name Register 2
Register Name: UNAME2
Access Type: Read-Only
Offset: 0x0828
Reset Value:
• UNAME2: IP Name Part Two
This field indicates the second part of the ASCII-encoded name of the USBC IP.
31 30 29 28 27 26 25 24
UNAME2[31:24]
23 22 21 20 19 18 17 16
UNAME2[23:16]
15 14 13 12 11 10 9 8
UNAME2[15:8]
76543210
UNAME2[7:0]
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8.7.1.10 Finite State Machine Status Register
Register Name: USBFSM
Access Type: Read-Only
Offset: 0x082C
Reset Value: 0x00000009
• DRDSTATE: Dual Role Device State
This field indicates the state of the USBC.
For Device mode it should always read 9.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - DRDSTATE
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8.7.1.11 USB Descriptor Address
Register Name: UDESC
Access Type: Read-Write
Offset: 0x0830
Reset Value: -
• UDESCA: USB Descriptor Address
This field contains the address of the USB descriptor. The three least significant bits are always zero.
31 30 29 28 27 26 25 24
UDESCA[31:24]
23 22 21 20 19 18 17 16
UDESCA[23:16]
15 14 13 12 11 10 9 8
UDESCA[15:8]
76543210
UDESCA[7:0]
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8.7.2 USB Device Registers
8.7.2.1 Device General Control Register
Register Name: UDCON
Access Type: Read/Write
Offset: 0x0000
Reset Value: 0x00000100
• GNAK: Global NAK
0: Normal mode.
1: A NAK handshake is answered for each USB transaction regardless of the current endpoint memory bank status.
• LS: low-speed mode force
0: The full-speed mode is active.
1: The low-speed mode is active.
This bit can be written to even if USBE is zero or FRZCLK is one. Disabling the USBC (by writing a zero to the USBE bit) does
not reset this bit.
• RMWKUP: Remote wakeup
Writing a zero to this bit has no effect.
Writing a one to this bit will send an upstream resume to the host for a remote wakeup.
This bit is cleared when the USBC receives a USB reset or once the upstream resume has been sent.
• DETACH: Detach
Writing a zero to this bit will reconnect the device.
Writing a one to this bit will physically detach the device (disconnect internal pull-up resistor from DP and DM).
• ADDEN: Address Enable
Writing a zero to this bit has no effect.
Writing a one to this bit will activate the UADD field (USB address).
This bit is cleared when a USB reset is received.
• UADD: USB Address
This field contains the device address.
This field is cleared when a USB reset is received.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - GNAK -
15 14 13 12 11 10 9 8
- - - LS - - RMWKUP DETACH
76543210
ADDEN UADD
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8.7.2.2 Device Global Interrupt Register
Register Name: UDINT
Access Type: Read-Only
Offset: 0x0004
Reset Value: 0x00000000
Note: 1. EPnINT bits are within the range from EP0INT to EP6INT.
• EPnINT: Endpoint n Interrupt
This bit is cleared when the interrupt source is serviced.
This bit is set when an interrupt is triggered by the endpoint n (UESTAn, UECONn). This triggers a USB interrupt if EPnINTE is
one.
• UPRSM: Upstream Resume Interrupt
This bit is cleared when the UDINTCLR.UPRSMC bit is written to one to acknowledge the interrupt (USB clock inputs must be
enabled before).
This bit is set when the USBC sends a resume signal called “Upstream Resume”. This triggers a USB interrupt if UPRSME is
one.
• EORSM: End of Resume Interrupt
This bit is cleared when the UDINTCLR.EORSMC bit is written to one to acknowledge the interrupt.
This bit is set when the USBC detects a valid “End of Resume” signal initiated by the host. This triggers a USB interrupt if
EORSME is one.
• WAKEUP: Wakeup Interrupt
This bit is cleared when the UDINTCLR.WAKEUPC bit is written to one to acknowledge the interrupt (USB clock inputs must be
enabled before) or when the Suspend (SUSP) interrupt bit is set.
This bit is set when the USBC is reactivated by a filtered non-idle signal from the lines (not by an upstream resume). This
triggers an interrupt if WAKEUPE is one.
This interrupt is generated even if the clock is frozen by the FRZCLK bit.
• EORST: End of Reset Interrupt
This bit is cleared when the UDINTCLR.EORSTC bit is written to one to acknowledge the interrupt.
This bit is set when a USB “End of Reset” has been detected. This triggers a USB interrupt if EORSTE is one.
• SOF: Start of Frame Interrupt
This bit is cleared when the UDINTCLR.SOFC bit is written to one to acknowledge the interrupt.
This bit is set when a USB “Start of Frame” PID (SOF) has been detected (every 1 ms). This triggers a USB interrupt if SOFE is
one. The FNUM field is updated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - EP8INT(1) EP7INT(1) EP6INT(1) EP5INT(1) EP4INT(1)
15 14 13 12 11 10 9 8
EP3INT(1) EP2INT(1) EP1INT(1) EP0INT - - - -
76543210
- UPRSM EORSM WAKEUP EORST SOF - SUSP
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• SUSP: Suspend Interrupt
This bit is cleared when the UDINTCLR.SUSPC bit is written to one to acknowledge the interrupt or when the Wakeup
(WAKEUP) interrupt bit is set.
This bit is set when a USB “Suspend” idle bus state has been detected for 3 frame periods (J state for 3 ms). This triggers a
USB interrupt if SUSPE is one.
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8.7.2.3 Device Global Interrupt Clear Register
Register Name: UDINTCLR
Access Type: Write-Only
Offset: 0x0008
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in UDINT.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- UPRSMC EORSMC WAKEUPC EORSTC SOFC - SUSPC
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8.7.2.4 Device Global Interrupt Set Register
Register Name: UDINTSET
Access Type: Write-Only
Offset: 0x000C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in UDINT, which may be useful for test or debug purposes.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- UPRSMS EORSMS WAKEUPS EORSTS SOFS - SUSPS
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8.7.2.5 Device Global Interrupt Enable Register
Register Name: UDINTE
Access Type: Read-Only
Offset: 0x0010
Reset Value: 0x00000000
Note: 1. EPnINTE bits are within the range from EP0INTE to EP6INTE.
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in UDINTECLR is written to one.
A bit in this register is set when the corresponding bit in UDINTESET is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - EP8INTE(1) EP7INTE(1) EP6INTE(1) EP5INTE(1) EP4INTE(1)
15 14 13 12 11 10 9 8
EP3INTE(1) EP2INTE(1) EP1INTE(1) EP0INTE - - - -
76543210
- UPRSME EORSME WAKEUPE EORSTE SOFE - SUSPE
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8.7.2.6 Device Global Interrupt Enable Clear Register
Register Name: UDINTECLR
Access Type: Write-Only
Offset: 0x0014
Reset Value: 0x00000000
Note: 1. EPnINTEC bits are within the range from EP0INTEC to EP6INTEC.
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in UDINTE.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - EP8INTEC(1) EP7INTEC(1) EP6INTEC(1) EP5INTEC(1) EP4INTEC(1)
15 14 13 12 11 10 9 8
EP3INTEC(1) EP2INTEC(1) EP1INTEC(1) EP0INTEC - - - -
76543210
- UPRSMEC EORSMEC WAKEUPEC EORSTEC SOFEC - SUSPEC
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8.7.2.7 Device Global Interrupt Enable Set Register
Register Name: UDINTESET
Access Type: Write-Only
Offset: 0x0018
Reset Value: 0x00000000
Note: 1. EPnINTES bits are within the range from EP0INTES to EP6INTES.
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in UDINTE.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - EP8INTES(1) EP7INTES(1) EP6INTES(1) EP5INTES(1) EP4INTES(1)
15 14 13 12 11 10 9 8
EP3INTES(1) EP2INTES(1) EP1INTES(1) EP0INTES - - - -
76543210
- UPRSMES EORSMES WAKEUPES EORSTES SOFES - SUSPES
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8.7.2.8 Endpoint Enable/Reset Register
Register Name: UERST
Access Type: Read/Write
Offset: 0x001C
Reset Value: 0x00000000
• EPENn: Endpoint n Enable
Note: 1. EPENn bits are within the range from EPEN0 to EPEN6.
Writing a zero to this bit will disable the endpoint n (USB requests will be ignored), and resets the endpoints registers (UECFGn,
UESTAn, UECONn), but not the endpoint configuration (EPBK, EPSIZE, EPDIR, EPTYPE).
Writing a one to this bit will enable the endpoint n.
0: The endpoint n is disabled.
1: The endpoint n is enabled.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - - EPEN8(1)
76543210
EPEN7(1) EPEN6(1) EPEN5(1) EPEN4(1) EPEN3(1) EPEN2(1) EPEN1(1) EPEN0
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8.7.2.9 Device Frame Number Register
Register Name: UDFNUM
Access Type: Read-Only
Offset: 0x0020
Reset Value: 0x00000000
• FNCERR: Frame Number CRC Error
This bit is cleared upon receiving a USB reset.
This bit is set when a corrupted frame number is received. This bit and the SOF interrupt bit are updated at the same time.
• FNUM: Frame Number
This field is cleared upon receiving a USB reset.
This field contains the 11-bit frame number information, as provided from the last SOF packet.
FNUM is updated even if a corrupted SOF is received.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
FNCERR - FNUM[10:5]
76543210
FNUM[4:0] - - -
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8.7.2.10 Endpoint n Configuration Register
Register Name: UECFGn, n in [0..6]
Access Type: Read/Write
Offset: 0x0100 + (n * 0x04)
Reset Value: 0x00000000
• EPTYPE: Endpoint Type
This field selects the endpoint type:
This field is cleared upon receiving a USB reset.
• EPDIR: Endpoint Direction
0: The endpoint direction is OUT.
1: The endpoint direction is IN (nor for control endpoints).
This bit is cleared upon receiving a USB reset.
• EPSIZE: Endpoint Size
This field determines the size of each endpoint bank:
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - EPTYPE - - EPDIR
76543210
- EPSIZE - EPBK - -
EPTYPE Endpoint Type
0 0 Control
0 1 Isochronous
1 0 Bulk
1 1 Interrupt
EPSIZE Endpoint Size
0 0 0 8 bytes
0 0 1 16 bytes
0 1 0 32 bytes
0 1 1 64 bytes
1 0 0 128 bytes
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This field is cleared upon receiving a USB reset (except for the endpoint 0).
• EPBK: Endpoint Banks
This bit selects the number of banks for the endpoint:
0: single-bank endpoint
1: double-bank endpoint
For control endpoints, a single-bank endpoint shall be selected.
This field is cleared upon receiving a USB reset (except for the endpoint 0).
1 0 1 256 bytes
1 1 0 512 bytes
1 1 1 1024 bytes
EPSIZE Endpoint Size
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8.7.2.11 Endpoint n Status Register
Register Name: UESTAn, n in [0..6]
Access Type: Read-Only 0x0100
Offset: 0x0130 + (n * 0x04)
Reset Value: 0x00000000
• CTRLDIR: Control Direction
Writing a zero or a one to this bit has no effect.
This bit is cleared after a SETUP packet to indicate that the following packet is an OUT packet.
This bit is set after a SETUP packet to indicate that the following packet is an IN packet.
• CURRBK: Current Bank
This bit is set for non-control endpoints, indicating the current bank:
This field may be updated one clock cycle after the RWALL bit changes, so the user should not poll this field as an interrupt bit.
• NBUSYBK: Number of Busy Banks
This field is set to indicate the number of busy banks:
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - CTRLDIR -
15 14 13 12 11 10 9 8
CURRBK NBUSYBK RAMACERI - DTSEQ
76543210
- STALLEDI/
CRCERRI - NAKINI NAKOUTI RXSTPI/
ERRORFI RXOUTI TXINI
CURRBK Current Bank
0 0 Bank0
0 1 Bank1
1 0 Reserved
1 1 Reserved
NBUSYBK Number of Busy Banks
0 0 0 (all banks free)
0 11
1 02
1 1 Reserved
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For IN endpoints, this indicates the number of banks filled by the user and ready for IN transfers. When all banks are free an
EPnINT interrupt will be triggered if NBUSYBKE is one.
For OUT endpoints, this indicates the number of banks filled by OUT transactions from the host. When all banks are busy an
EPnINT interrupt will be triggered if NBUSYBKE is one.
• RAMACERI: Ram Access Error Interrupt
This bit is cleared when the RAMACERIC bit is written to one, acknowledging the interrupt.
This bit is set when a RAM access underflow error occurs during an IN data stage.
• DTSEQ: Data Toggle Sequence
This field is set to indicate the PID of the current bank:
For IN transfers, this indicates the data toggle sequence that will be used for the next packet to be sent.
For OUT transfers, this value indicates the data toggle sequence of the data received in the current bank.
• STALLEDI: STALLed Interrupt
This bit is cleared when the STALLEDIC bit is written to one, acknowledging the interrupt.
This bit is set when a STALL handshake has been sent and triggers an EPnINT interrupt if STALLEDE is one.
• CRCERRI: CRC Error Interrupt
This bit is cleared when the CRCERRIC bit is written to one, acknowledging the interrupt.
This bit is set when a CRC error has been detected in an isochronous OUT endpoint bank, and triggers an EPnINT interrupt if
CRCERRE is one.
• NAKINI: NAKed IN Interrupt
This bit is cleared when the NAKINIC bit is written to one, acknowledging the interrupt.
This bit is set when a NAK handshake has been sent in response to an IN request from the host, and triggers an EPnINT
interrupt if NAKINE is one.
• NAKOUTI: NAKed OUT Interrupt
This bit is cleared when the NAKOUTIC bit is written to one, acknowledging the interrupt.
This bit is set when a NAK handshake has been sent in response to an OUT request from the host, and triggers an EPnINT
interrupt if NAKOUTE is one.
• ERRORFI: Isochronous Error flow Interrupt
This bit is cleared when the ERRORFIC bit is written to one, acknowledging the interrupt.
This bit is set, for isochronous IN/OUT endpoints, when an errorflow (underflow or overflow) error occurs, and triggers an
EPnINT interrupt if ERRORFE is one.
An underflow can occur during IN stage if the host attempts to read from an empty bank. A zero-length packet is then
automatically sent by the USBC.
An overflow can also occur during OUT stage if the host sends a packet while the bank is already full, resulting in the packet
being lost. This is typically due to a CPU not being fast enough.
This bit is inactive (cleared) for bulk and interrupt IN/OUT endpoints and it means RXSTPI for control endpoints.
• RXSTPI: Received SETUP Interrupt
This bit is cleared when the RXSTPIC bit is written to one, acknowledging the interrupt and freeing the bank.
This bit is set, for control endpoints, to signal that the current bank contains a new valid SETUP packet, and triggers an EPnINT
interrupt if RXSTPE is one.
This bit is inactive (cleared) for bulk and interrupt IN/OUT endpoints and it means UNDERFI for isochronous IN/OUT endpoints.
• RXOUTI: Received OUT Data Interrupt
This bit is cleared when the RXOUTIC bit is written to one, acknowledging the interrupt. For control endpoints, it releases the
bank. For other endpoint types, the user should clear the FIFOCON bit to free the bank. RXOUTI shall always be cleared before
clearing FIFOCON to avoid missing an interrupt.
DTSEQ Data Toggle Sequence
0 0 Data0
0 1 Data1
1 X Reserved
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This bit is set, for control endpoints, when the current bank contains a bulk OUT packet (data or status stage). This triggers an
EPnINT interrupt if RXOUTE is one.
This bit is set for isochronous, bulk and, interrupt OUT endpoints, at the same time as FIFOCON when the current bank is full.
This triggers an EPnINT interrupt if RXOUTE is one.
This bit is inactive (cleared) for isochronous, bulk and interrupt IN endpoints.
• TXINI: Transmitted IN Data Interrupt
This bit is cleared when the TXINIC bit is written to one, acknowledging the interrupt. For control endpoints, this will send the
packet. For other endpoint types, the user should clear the FIFOCON to allow the USBC to send the data. TXINI shall always be
cleared before clearing FIFOCON to avoid missing an interrupt.
This bit is set for control endpoints, when the current bank is ready to accept a new IN packet. This triggers an EPnINT interrupt
if TXINE is one.
This bit is set for isochronous, bulk and interrupt IN endpoints, at the same time as FIFOCON when the current bank is free.
This triggers an EPnINT interrupt if TXINE is one.
This bit is inactive (cleared) for isochronous, bulk and interrupt OUT endpoints.
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8.7.2.12 Endpoint n Status Clear Register
Register Name: UESTAnCLR, n in [0..6]
Access Type: Write-Only
Offset: 0x0160 + (n * 0x04)
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in UESTA.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - RAMACERIC - - -
76543210
- STALLEDIC/
CRCERRIC - NAKINIC NAKOUTIC RXSTPIC/
ERRORFIC RXOUTIC TXINIC
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8.7.2.13 Endpoint n Status Set Register
Register Name: UESTAnSET, n in [0..6]
Access Type: Write-Only
Offset: 0x0190 + (n * 0x04)
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in UESTA.
These bits always read as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - NBUSYBKS RAMACERIS - -
76543210
- STALLEDIS/
CRCERRIS - NAKINIS NAKOUTIS RXSTPIS/
ERRORFIS RXOUTIS TXINIS
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8.7.2.14 Endpoint n Control Register
Register Name: UECONn, n in [0..6]
Access Type: Read-Only
Offset: 0x01C0 + (n * 0x04)
Reset Value: 0x00000000
• BUSY0E: Busy Bank0 Enable
This bit is cleared when the BUSY0C bit is written to one.
This bit is set when the BUSY0ES bit is written to one. This will set the bank 0 as “busy”. All transactions, except SETUP,
destined to this bank will be rejected (i.e: NAK token will be answered).
• BUSY1E: Busy Bank1 Enable
This bit is cleared when the BUSY1C bit is written to one.
This bit is set when the BUSY1ES bit is written to one. This will set the bank 1 as “busy”. All transactions, except SETUP,
destined to this bank will be rejected (i.e: NAK token will be answered).
• STALLRQ: STALL Request
This bit is cleared when a new SETUP packet is received or when the STALLRQC bit is written to zero.
This bit is set when the STALLRQS bit is written to one, requesting a STALL handshake to be sent to the host.
• RSTDT: Reset Data Toggle
The data toggle sequence is cleared when the RSTDTS bit is written to one (i.e., Data0 data toggle sequence will be selected
for the next sent (IN endpoints) or received (OUT endpoints) packet.
This bit is always read as zero.
• FIFOCON: FIFO Control
For control endpoints:
The FIFOCON and RWALL bits are irrelevant. The software shall therefore never use them for these endpoints. When read,
their value is always 0.
For IN endpoints:
This bit is cleared when the FIFOCONC bit is written to one, sending the FIFO data and switching to the next bank.
This bit is set simultaneously to TXINI, when the current bank is free.
For OUT endpoints:
This bit is cleared when the FIFOCONC bit is written to one, freeing the current bank and switching to the next.
This bit is set simultaneously to RXINI, when the current bank is full.
31 30 29 28 27 26 25 24
- - - - - - BUSY1E BUSY0E
23 22 21 20 19 18 17 16
- - - - STALLRQ RSTDT - -
15 14 13 12 11 10 9 8
- FIFOCON KILLBK NBUSYBKE RAMACERE - -
76543210
- STALLEDE/
CRCERRE - NAKINE NAKOUTE RXSTPE/
ERRORFE RXOUTE TXINE
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• KILLBK: Kill IN Bank
This bit is cleared by hardware after the completion of the “kill packet procedure”.
This bit is set when the KILLBKS bit is written to one, killing the last written bank.
The user shall wait for this bit to be cleared before trying to process another IN packet.
Caution: The bank is cleared when the “kill packet” procedure is completed by the USBC core:
If the bank is really killed, the NBUSYBK field is decremented.
If the bank sent instead of killed (IN transfer), the NBUSYBK field is decremented and the TXINI flag is set. This specific case
can occur if an IN token comes while the user tries to kill the bank.
Note: If two banks are ready to be sent, the above specific case will not occur, since the first bank is sent (IN transfer) while the
last bank is killed.
• NBUSYBKE: Number of Busy Banks Interrupt Enable
This bit is cleared when the NBUSYBKEC bit is written to zero, disabling the Number of Busy Banks interrupt (NBUSYBK).
This bit is set when the NBUSYBKES bit is written to one, enabling the Number of Busy Banks interrupt (NBUSYBK).
• RAMACERE: RAMACER Interrupt Enable
This bit is cleared when the RAMACEREC bit is written to one, disabling the RAMACER interrupt (RAMACERI).
This bit is set when the RAMACERES bit is written to one, enabling the RAMACER interrupt (RAMACERI).
• STALLEDE: STALLed Interrupt Enable
This bit is cleared when the STALLEDEC bit is written to one, disabling the STALLed interrupt (STALLEDI).
This bit is set when the STALLEDES bit is written to one, enabling the STALLed interrupt (STALLEDI).
• CRCERRE: CRC Error Interrupt Enable
This bit is cleared when the CRCERREC bit is written to one, disabling the CRC Error interrupt (CRCERRI).
This bit is set when the CRCERRES bit is written to one, enabling the CRC Error interrupt (CRCERRI).
• NAKINE: NAKed IN Interrupt Enable
This bit is cleared when the NAKINEC bit is written to one, disabling the NAKed IN interrupt (NAKINI).
This bit is set when the NAKINES bit is written to one, enabling the NAKed IN interrupt (NAKINI).
• NAKOUTE: NAKed OUT Interrupt Enable
This bit is cleared when the NAKOUTEC bit is written to one, disabling the NAKed OUT interrupt (NAKOUTI).
This bit is set when the NAKOUTES bit is written to one, enabling the NAKed OUT interrupt (NAKOUTI).
• RXSTPE: Received SETUP Interrupt Enable
This bit is cleared when the RXSTPEC bit is written to one, disabling the Received SETUP interrupt (RXSTPI).
This bit is set when the RXSTPES bit is written to one, enabling the Received SETUP interrupt (RXSTPI).
• ERRORFE: Errorflow Interrupt Enable
This bit is cleared when the ERRORFEC bit is written to one, disabling the Underflow interrupt (ERRORFI).
This bit is set when the ERRORFES bit is written to one, enabling the Underflow interrupt (ERRORFI).
• RXOUTE: Received OUT Data Interrupt Enable
This bit is cleared when the RXOUTEC bit is written to one, disabling the Received OUT Data interrupt (RXOUT).
This bit is set when the RXOUTES bit is written to one, enabling the Received OUT Data interrupt (RXOUT).
• TXINE: Transmitted IN Data Interrupt Enable
This bit is cleared when the TXINEC bit is written to one, disabling the Transmitted IN Data interrupt (TXINI).
This bit is set when the TXINES bit is written to one, enabling the Transmitted IN Data interrupt (TXINI).
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8.7.2.15 Endpoint n Control Clear Register
Register Name: UECONnCLR, n in [0..6]
Access Type: Write-Only
Offset: 0x0220 + (n * 0x04)
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in UECONn.
These bits always read as zero.
31 30 29 28 27 26 25 24
- - - - - - BUSY1EC BUSY0EC
23 22 21 20 19 18 17 16
- - - - STALLRQC - - -
15 14 13 12 11 10 9 8
- FIFOCONC - NBUSYBKEC RAMACEREC - - -
76543210
- STALLEDEC/
CRCERREC - NAKINEC NAKOUTEC RXSTPEC/
ERRORFEC RXOUTEC TXINEC
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8.7.2.16 Endpoint n Control Set Register
Register Name: UECONnSET, n in [0..6]
Access Type: Write-Only
Offset: 0x01F0 + (n * 0x04)
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in UECONn.
These bits always read as zero.
•
•
31 30 29 28 27 26 25 24
- - - - - - BUSY1ES BUSY0ES
23 22 21 20 19 18 17 16
- - - - STALLRQS RSTDTS - -
15 14 13 12 11 10 9 8
- - KILLBKS NBUSYBKES RAMACERES ---
76543210
- STALLEDES/
CRCERRES - NAKINES NAKOUTES RXSTPES/
ERRORFES RXOUTES TXINES
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8.8 Module Configuration
The specific configuration for each USBC instance is listed in the following tables. The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 8-6. USBC Clocks
Clock Name Description
CLK_USBC_PB Clock for the USBC PB interface
CLK_USBC_HSB Clock for the USBC HSB interface
GCLK_USBC The generic clock used for the USBC is GCLK7
Table 8-7. Register Reset Values
Register Reset Value
UVERS 0x00000200
UFEATURES 0x00000007
UADDRSIZE 0x00001000
UNAME1 0x48555342
UNAME2 0x00000000
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9. Flash Controller (FLASHCDW)
Rev: 1.2.0.0
9.1 Features
• Controls on-chip flash memory
• Supports 0 and 1 wait state bus access
• Buffers reducing penalty of wait state in sequential code or loops
• Allows interleaved burst reads for systems with one wait state, outputting one 32-bit word per
clock cycle for sequential reads
• Secure State for supporting FlashVault technology
• 32-bit HSB interface for reads from flash and writes to page buffer
• 32-bit PB interface for issuing commands to and configuration of the controller
• Flash memory is divided into 16 regions can be individually protected or unprotected
• Additional protection of the Boot Loader pages
• Supports reads and writes of general-purpose Non Volatile Memory (NVM) bits
• Supports reads and writes of additional NVM pages
• Supports device protection through a security bit
• Dedicated command for chip-erase, first erasing all on-chip volatile memories before erasing
flash and clearing security bit
9.2 Overview
The Flash Controller (FLASHCDW) interfaces the on-chip flash memory with the 32-bit internal
HSB bus. The controller manages the reading, writing, erasing, locking, and unlocking
sequences.
9.3 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
9.3.1 Power Management
If the CPU enters a sleep mode that disables clocks used by the FLASHCDW, the FLASHCDW
will stop functioning and resume operation after the system wakes up from sleep mode.
9.3.2 Clocks
The FLASHCDW has two bus clocks connected: One High Speed Bus clock
(CLK_FLASHCDW_HSB) and one Peripheral Bus clock (CLK_FLASHCDW_PB). These clocks
are generated by the Power Manager. Both clocks are enabled at reset, and can be disabled by
writing to the Power Manager. The user has to ensure that CLK_FLASHCDW_HSB is not turned
off before reading the flash or writing the pagebuffer and that CLK_FLASHCDW_PB is not
turned off before accessing the FLASHCDW configuration and control registers. Failing to do so
may deadlock the bus.
9.3.3 Interrupts
The FLASHCDW interrupt request lines are connected to the interrupt controller. Using the
FLASHCDW interrupts requires the interrupt controller to be programmed first.
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9.3.4 Debug Operation
When an external debugger forces the CPU into debug mode, the FLASHCDW continues normal
operation. If the FLASHCDW is configured in a way that requires it to be periodically
serviced by the CPU through interrupts or similar, improper operation or data loss may result
during debugging.
9.4 Functional Description
9.4.1 Bus Interfaces
The FLASHCDW has two bus interfaces, one High Speed Bus (HSB) interface for reads from the
flash memory and writes to the page buffer, and one Peripheral Bus (PB) interface for issuing
commands and reading status from the controller.
9.4.2 Memory Organization
The flash memory is divided into a set of pages. A page is the basic unit addressed when programming
the flash. A page consists of several words. The pages are grouped into 16 regions of
equal size. Each of these regions can be locked by a dedicated fuse bit, protecting it from accidental
modification.
• p pages (FLASH_P)
• w bytes in each page and in the page buffer (FLASH_W)
• pw bytes in total (FLASH_PW)
• f general-purpose fuse bits (FLASH_F), used as region lock bits and for other device-specific
purposes
• 1 security fuse bit
• 1 User page
9.4.3 User Page
The User page is an additional page, outside the regular flash array, that can be used to store
various data, such as calibration data and serial numbers. This page is not erased by regular
chip erase. The User page can only be written and erased by a special set of commands. Read
accesses to the User page are performed just as any other read accesses to the flash. The
address map of the User page is given in Figure 9-1 on page 138.
9.4.4 Read Operations
The on-chip flash memory is typically used for storing instructions to be executed by the CPU.
The CPU will address instructions using the HSB bus, and the FLASHCDW will access the flash
memory and return the addressed 32-bit word.
In systems where the HSB clock period is slower than the access time of the flash memory, the
FLASHCDW can operate in 0 wait state mode, and output one 32-bit word on the bus per clock
cycle. If the clock frequency allows, the user should use 0 wait state mode, because this gives
the highest performance as no stall cycles are encountered.
The FLASHCDW can also operate in systems where the HSB bus clock period is faster than the
access speed of the flash memory. Wait state support and a read granularity of 64 bits ensure
efficiency in such systems.
Performance for systems with high clock frequency is increased since the internal read word
width of the flash memory is 64 bits. When a 32-bit word is to be addressed, the word itself and
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also the other word in the same 64-bit location is read. The first word is output on the bus, and
the other word is put into an internal buffer. If a read to a sequential address is to be performed
in the next cycle, the buffered word is output on the bus, while the next 64-bit location is read
from the flash memory. Thus, latency in 1 wait state mode is hidden for sequential fetches.
The programmer can select the wait states required by writing to the FWS field in the Flash Control
Register (FCR). It is the responsibility of the programmer to select a number of wait states
compatible with the clock frequency and timing characteristics of the flash memory.
In 0ws mode, no wait states are encountered on any flash read operations. In 1 ws mode, one
stall cycle is encountered on the first access in a single or burst transfer. In 1 ws mode, if the first
access in a burst access is to an address that is not 64-bit aligned, an additional stall cycle is
also encountered when reading the second word in the burst. All subsequent words in the burst
are accessed without any stall cycles.
The Flash Controller provides two sets of buffers that can be enabled in order to speed up
instruction fetching. These buffers can be enabled by writing a one to the FCR.SEQBUF and
FCR.BRBUF bits. The SEQBUF bit enables buffering hardware optimizing sequential instruction
fetches. The BRBUF bit enables buffering hardware optimizing tight inner loops. These buffers
are never used when the flash is in 0 wait state mode. Usually, both these buffers should be
enabled when operating in 1 wait state mode. Some users requiring absolute cycle determinism
may want to keep the buffers disabled.
The Flash Controller address space is displayed in Figure 9-1. The memory space between
address pw and the User page is reserved, and reading addresses in this space returns an
undefined result. The User page is permanently mapped to an offset of 0x00800000 from the
start address of the flash memory.
Table 9-1. User Page Addresses
Memory type Start address, byte sized Size
Main array 0 pw bytes
User 0x00800000 w bytes
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Figure 9-1. Memory Map for the Flash Memories
9.4.5 High Speed Read Mode
The flash provides a High Speed Read Mode, offering slightly higher flash read speed at the
cost of higher power consumption. Two dedicated commands, High Speed Read Mode Enable
(HSEN) and High Speed Read Mode Disable (HSDIS) control the speed mode. The High Speed
Mode (HSMODE) bit in the Flash Status Register (FSR) shows which mode the flash is in. After
reset, the High Speed Mode is disabled, and must be manually enabled if the user wants to.
Refer to the Electrical Characteristics chapter at the end of this datasheet for details on the maximum
clock frequencies in Normal and High Speed Read Mode.
0
pw
Reserved Flash data array
Reserved User Page
Flash with User Page
0x0080 0000
All addresses are byte addresses
Flash base address
Offset from
base address
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Figure 9-2. High Speed Mode
9.4.6 Quick Page Read
A dedicated command, Quick Page Read (QPR), is provided to read all words in an addressed
page. All bits in all words in this page are AND’ed together, returning a 1-bit result. This result is
placed in the Quick Page Read Result (QPRR) bit in Flash Status Register (FSR). The QPR
command is useful to check that a page is in an erased state. The QPR instruction is much
faster than performing the erased-page check using a regular software subroutine.
9.4.7 Quick User Page Read
A dedicated command, Quick User Page Read (QPRUP), is provided to read all words in the
user page. All bits in all words in this page are AND’ed together, returning a 1-bit result. This
result is placed in the Quick Page Read Result (QPRR) bit in Flash Status Register (FSR). The
QPRUP command is useful to check that a page is in an erased state. The QPRUP instruction is
much faster than performing the erased-page check using a regular software subroutine.
9.4.8 Page Buffer Operations
The flash memory has a write and erase granularity of one page; data is written and erased in
chunks of one page. When programming a page, the user must first write the new data into the
Page Buffer. The contents of the entire Page Buffer is copied into the desired page in flash
memory when the user issues the Write Page command, Refer to Section 9.5.1 on page 141.
In order to program data into flash page Y, write the desired data to locations Y0 to Y31 in the
regular flash memory map. Writing to an address A in the flash memory map will not update the
flash memory, but will instead update location A%32 in the page buffer. The PAGEN field in the
Flash Command (FCMD) register will at the same time be updated with the value A/32.
Frequency
Frequency limit
for 0 wait state
operation
Normal
High
Speed mode
1 wait state
0 wait state
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Figure 9-3. Mapping from Page Buffer to Flash
Internally, the flash memory stores data in 64-bit doublewords. Therefore, the native data size of
the Page Buffer is also a 64-bit doubleword. All locations shown in Figure 9-3 are therefore doubleword
locations. Since the HSB bus only has a 32-bit data width, two 32-bit HSB transfers
must be performed to write a 64-bit doubleword into the Page Buffer. The FLASHCDW has logic
to combine two 32-bit HSB transfers into a 64-bit data before writing this 64-bit data into the
Page Buffer. This logic requires the word with the low address to be written to the HSB bus
before the word with the high address. To exemplify, to write a 64-bit value to doubleword X0
residing in page X, first write a 32-bit word to the byte address pointing to address X0, thereafter
write a word to the byte address pointing to address (X0+4).
The page buffer is word-addressable and should only be written with aligned word transfers,
never with byte or halfword transfers. The page buffer can not be read.
The page buffer is also used for writes to the User page.
Page buffer write operations are performed with 4 wait states. Any accesses attempted to the
FLASHCDW on the HSB bus during these cycles will be automatically stalled.
Writing to the page buffer can only change page buffer bits from one to zero, i.e. writing
0xAAAAAAAA to a page buffer location that has the value 0x00000000 will not change the page
buffer value. The only way to change a bit from zero to one is to erase the entire page buffer with
the Clear Page Buffer command.
Z3 Z2 Z1 Z0
Z7 Z6 Z5 Z4
Z11 Z10 Z9 Z8
Z15 Z14 Z13 Z12
Z19 Z18 Z17 Z16
Z23 Z22 Z21 Z20
Z27 Z26 Z25 Z24
Z31 Z30 Z29 Z28
Y3 Y2 Y1 Y0
Y7 Y6 Y5 Y4
Y11 Y10 Y9 Y8
Y15 Y14 Y13 Y12
Y19 Y18 Y17 Y16
Y23 Y22 Y21 Y20
Y27 Y26 Y25 Y24
Y31 Y30 Y29 Y28
X3 X2 X1 X0
X7 X6 X5 X4
X11 X10 X9 X8
X15 X14 X13 X12
X19 X18 X17 X16
X23 X22 X21 X20
X27 X26 X25 X24
X31 X30 X29 X28
3 2 1 0
7 6 5 4
11 10 9 8
15 14 13 12
19 18 17 16
23 22 21 20
27 26 25 24
31 30 29 28
Page X
Page Y
Page Z
Page Buffer
64-bit data
Flash
All locations are doubleword locations
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The page buffer is not automatically reset after a page write. The programmer should do this
manually by issuing the Clear Page Buffer flash command. This can be done after a page write,
or before the page buffer is loaded with data to be stored to the flash page.
9.5 Flash Commands
The FLASHCDW offers a command set to manage programming of the flash memory, locking
and unlocking of regions, and full flash erasing. See Section 9.8.2 for a complete list of
commands.
To run a command, the CMD field in the Flash Command Register (FCMD) has to be written
with the command number. As soon as the FCMD register is written, the FRDY bit in the Flash
Status Register (FSR) is automatically cleared. Once the current command is complete, the
FSR.FRDY bit is automatically set. If an interrupt has been enabled by writing a one to
FCR.FRDY, the interrupt request line of the Flash Controller is activated. All flash commands
except for Quick Page Read (QPR) and Quick User Page Read (QPRUP) will generate an interrupt
request upon completion if FCR.FRDY is one.
Any HSB bus transfers attempting to read flash memory when the FLASHCDW is busy executing
a flash command will be stalled, and allowed to continue when the flash command is
complete.
After a command has been written to FCMD, the programming algorithm should wait until the
command has been executed before attempting to read instructions or data from the flash or
writing to the page buffer, as the flash will be busy. The waiting can be performed either by polling
the Flash Status Register (FSR) or by waiting for the flash ready interrupt. The command
written to FCMD is initiated on the first clock cycle where the HSB bus interface in FLASHCDW
is IDLE. The user must make sure that the access pattern to the FLASHCDW HSB interface
contains an IDLE cycle so that the command is allowed to start. Make sure that no bus masters
such as DMA controllers are performing endless burst transfers from the flash. Also, make sure
that the CPU does not perform endless burst transfers from flash. This is done by letting the
CPU enter sleep mode after writing to FCMD, or by polling FSR for command completion. This
polling will result in an access pattern with IDLE HSB cycles.
All the commands are protected by the same keyword, which has to be written in the eight highest
bits of the FCMD register. Writing FCMD with data that does not contain the correct key
and/or with an invalid command has no effect on the flash memory; however, the PROGE bit is
set in the Flash Status Register (FSR). This bit is automatically cleared by a read access to the
FSR register.
Writing a command to FCMD while another command is being executed has no effect on the
flash memory; however, the PROGE bit is set in the Flash Status Register (FSR). This bit is
automatically cleared by a read access to the FSR register.
If the current command writes or erases a page in a locked region, or a page protected by the
BOOTPROT fuses, the command has no effect on the flash memory; however, the LOCKE bit is
set in the FSR register. This bit is automatically cleared by a read access to the FSR register.
9.5.1 Write/Erase Page Operation
Flash technology requires that an erase must be done before programming. The entire flash can
be erased by an Erase All command. Alternatively, pages can be individually erased by the
Erase Page command.
The User page can be written and erased using the mechanisms described in this chapter.
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After programming, the page can be locked to prevent miscellaneous write or erase sequences.
Locking is performed on a per-region basis, so locking a region locks all pages inside the region.
Additional protection is provided for the lowermost address space of the flash. This address
space is allocated for the Boot Loader, and is protected both by the lock bit(s) corresponding to
this address space, and the BOOTPROT[2:0] fuses.
Data to be written is stored in an internal buffer called the page buffer. The page buffer contains
w words. The page buffer wraps around within the internal memory area address space and
appears to be repeated by the number of pages in it. Writing of 8-bit and 16-bit data to the page
buffer is not allowed and may lead to unpredictable data corruption.
Data must be written to the page buffer before the programming command is written to the Flash
Command Register (FCMD). The sequence is as follows:
• Reset the page buffer with the Clear Page Buffer command.
• Fill the page buffer with the desired contents as described in Section 9.4.8 on page 139.
• Programming starts as soon as the programming key and the programming command are
written to the Flash Command Register. The PAGEN field in the Flash Command Register
(FCMD) must contain the address of the page to write. PAGEN is automatically updated
when writing to the page buffer, but can also be written to directly. The FRDY bit in the Flash
Status Register (FSR) is automatically cleared when the page write operation starts.
• When programming is completed, the FRDY bit in the Flash Status Register (FSR) is set. If
an interrupt was enabled by writing FCR.FRDY to one, an interrupt request is generated.
Two errors can be detected in the FSR register after a programming sequence:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
• Lock Error: Can have two different causes:
– The page to be programmed belongs to a locked region. A command must be
executed to unlock the corresponding region before programming can start.
– A bus master without secure status attempted to program a page requiring secure
privileges.
9.5.2 Erase All Operation
The entire memory is erased if the Erase All command (EA) is written to the Flash Command
Register (FCMD). Erase All erases all bits in the flash array. The User page is not erased. All
flash memory locations, the general-purpose fuse bits, and the security bit are erased (reset to
0xFF) after an Erase All.
The EA command also ensures that all volatile memories, such as register file and RAMs, are
erased before the security bit is erased.
Erase All operation is allowed only if no regions are locked, and the BOOTPROT fuses are configured
with a BOOTPROT region size of 0. Thus, if at least one region is locked, the bit LOCKE
in FSR is set and the command is cancelled. If the LOCKE bit in FCR is one, an interrupt request
is set generated.
When the command is complete, the FRDY bit in the Flash Status Register (FSR) is set. If an
interrupt has been enabled by writing FCR.FRDY to one, an interrupt request is generated. Two
errors can be detected in the FSR register after issuing the command:
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• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
• Lock Error: At least one lock region is protected, or BOOTPROT is different from 0. The erase
command has been aborted and no page has been erased. A “Unlock region containing
given page” (UP) command must be executed to unlock any locked regions.
9.5.3 Region Lock Bits
The flash memory has p pages, and these pages are grouped into 16 lock regions, each region
containing p/16 pages. Each region has a dedicated lock bit preventing writing and erasing
pages in the region. After production, the device may have some regions locked. These locked
regions are reserved for a boot or default application. Locked regions can be unlocked to be
erased and then programmed with another application or other data.
To lock or unlock a region, the commands Lock Region Containing Page (LP) and Unlock
Region Containing Page (UP) are provided. Writing one of these commands, together with the
number of the page whose region should be locked/unlocked, performs the desired operation.
One error can be detected in the FSR register after issuing the command:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
The lock bits are implemented using the lowest 16 general-purpose fuse bits. This means that
lock bits can also be set/cleared using the commands for writing/erasing general-purpose fuse
bits, see Section 9.6. The general-purpose bit being in an erased (1) state means that the region
is unlocked.
The lowermost pages in the flash can additionally be protected by the BOOTPROT fuses, see
Section 9.6.
9.6 General-purpose Fuse Bits
The flash memory has a number of general-purpose fuse bits that the application programmer
can use freely. The fuse bits can be written and erased using dedicated commands, and read
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through a dedicated Peripheral Bus address. Some of the general-purpose fuse bits are
reserved for special purposes, and should not be used for other functions:
The BOOTPROT fuses protects the following address space for the Boot Loader:
Table 9-2. General-purpose Fuses with Special Functions
GeneralPurpose
fuse
number Name Usage
15:0 LOCK Region lock bits.
16 EPFL
External Privileged Fetch Lock. Used to prevent the CPU from
fetching instructions from external memories when in privileged
mode. This bit can only be changed when the security bit is
cleared. The address range corresponding to external
memories is device-specific, and not known to the Flash
Controller. This fuse bit is simply routed out of the CPU or bus
system, the Flash Controller does not treat this fuse in any
special way, except that it can not be altered when the security
bit is set.
If the security bit is set, only an external JTAG or aWire Chip
Erase can clear EPFL. No internal commands can alter EPFL if
the security bit is set.
When the fuse is erased (i.e. "1"), the CPU can execute
instructions fetched from external memories. When the fuse is
programmed (i.e. "0"), instructions can not be executed from
external memories.
This fuse has no effect in devices with no External Memory
Interface (EBI).
19:17 BOOTPROT
Used to select one of eight different bootloader sizes. Pages
included in the bootloader area can not be erased or
programmed except by a JTAG or aWire chip erase.
BOOTPROT can only be changed when the security bit is
cleared.
If the security bit is set, only an external JTAG or aWire Chip
Erase can clear BOOTPROT, and thereby allow the pages
protected by BOOTPROT to be programmed. No internal
commands can alter BOOTPROT or the pages protected by
BOOTPROT if the security bit is set.
21:20 SECURE
Used to configure secure state and secure state debug
capabilities. Decoded into SSE and SSDE signals as shown in
Table 9-5. Refer to the AVR32 Architecture Manual and the
AVR32UC Technical Reference Manual for more details on
SSE and SSDE.
22 UPROT
If programmed (i.e. “0”), the JTAG USER PROTECTION
feature is enabled. If this fuse is programmed some HSB
addresses will be accessible by JTAG access even if the flash
security fuse is programmed. Refer to the JTAG documentation
for more information on this functionality. This bit can only be
changed when the security bit is cleared.
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The SECURE fuses have the following functionality:
To erase or write a general-purpose fuse bit, the commands Write General-Purpose Fuse Bit
(WGPB) and Erase General-Purpose Fuse Bit (EGPB) are provided. Writing one of these commands,
together with the number of the fuse to write/erase, performs the desired operation.
An entire General-Purpose Fuse byte can be written at a time by using the Program GP Fuse
Byte (PGPFB) instruction. A PGPFB to GP fuse byte 2 is not allowed if the flash is locked by the
security bit. The PFB command is issued with a parameter in the PAGEN field:
• PAGEN[2:0] - byte to write
• PAGEN[10:3] - Fuse value to write
All general-purpose fuses can be erased by the Erase All General-Purpose fuses (EAGP) command.
An EAGP command is not allowed if the flash is locked by the security bit.
Two errors can be detected in the FSR register after issuing these commands:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
• Lock Error:
– A write or erase of the BOOTPROT or EPFL or UPROT fuse bits was attempted
while the flash is locked by the security bit.
– A write or erase of the SECURE fuse bits was attempted when SECURE mode was
enabled.
The lock bits are implemented using the lowest 16 general-purpose fuse bits. This means that
the 16 lowest general-purpose fuse bits can also be written/erased using the commands for
locking/unlocking regions, see Section 9.5.3.
Table 9-3. Boot Loader Area Specified by BOOTPROT
BOOTPROT
Pages protected by
BOOTPROT
Size of protected
memory
7 None 0
6 0-1 1Kbyte
5 0-3 2Kbyte
4 0-7 4Kbyte
3 0-15 8Kbyte
2 0-31 16Kbyte
1 0-63 32Kbyte
0 0-127 64Kbyte
Table 9-5. Secure State Configuration
SECURE Functionality SSE SSDE
00 Secure state disabled 0 0
01 Secure enabled, secure state debug enabled 1 1
10 Secure enabled, secure state debug disabled 1 0
11 Secure state disabled 0 0
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9.7 Security Bit
The security bit allows the entire device to be locked from external JTAG, aWire, or other debug
access for code security. The security bit can be written by a dedicated command, Set Security
Bit (SSB). Once set, the only way to clear the security bit is through the JTAG or aWire Chip
Erase command.
Once the security bit is set, the following Flash Controller commands will be unavailable and
return a lock error if attempted:
• Write General-Purpose Fuse Bit (WGPB) to BOOTPROT or EPFL fuses
• Erase General-Purpose Fuse Bit (EGPB) to BOOTPROT or EPFL fuses
• Program General-Purpose Fuse Byte (PGPFB) of fuse byte 2
• Erase All General-Purpose Fuses (EAGPF)
One error can be detected in the FSR register after issuing the command:
• Programming Error: A bad keyword and/or an invalid command have been written in the
FCMD register.
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9.8 User Interface
Note: 1. The value of the Lock bits depend on their programmed state. All other bits in FSR are 0.
2. All bits in FGPRHI/LO are dependent on the programmed state of the fuses they map to. Any bits in these registers not
mapped to a fuse read as 0.
3. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 9-6. FLASHCDW Register Memory Map
Offset Register Register Name Access Reset
0x00 Flash Control Register FCR Read/Write 0x00000000
0x04 Flash Command Register FCMD Read/Write 0x00000000
0x08 Flash Status Register FSR Read-only -(1)
0x0C Flash Parameter Register FPR Read-only -(3)
0x10 Flash Version Register FVR Read-only -(3)
0x14 Flash General Purpose Fuse Register Hi FGPFRHI Read-only -(2)
0x18 Flash General Purpose Fuse Register Lo FGPFRLO Read-only -(2)
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9.8.1 Flash Control Register
Name: FCR
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• BRBUF: Branch Target Instruction Buffer Enable
0: The Branch Target Instruction Buffer is disabled.
1: The Branch Target Instruction Buffer is enabled.
• SEQBUF: Sequential Instruction Fetch Buffer Enable
0: The Sequential Instruction Fetch Buffer is disabled.
1: The Sequential Instruction Fetch Buffer is enabled.
• FWS: Flash Wait State
0: The flash is read with 0 wait states.
1: The flash is read with 1 wait state.
• PROGE: Programming Error Interrupt Enable
0: Programming Error does not generate an interrupt request.
1: Programming Error generates an interrupt request.
• LOCKE: Lock Error Interrupt Enable
0: Lock Error does not generate an interrupt request.
1: Lock Error generates an interrupt request.
• FRDY: Flash Ready Interrupt Enable
0: Flash Ready does not generate an interrupt request.
1: Flash Ready generates an interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - BRBUF SEQBUF -
76543210
- FWS - - PROGE LOCKE - FRDY
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9.8.2 Flash Command Register
Name: FCMD
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
The FCMD can not be written if the flash is in the process of performing a flash command. Doing
so will cause the FCR write to be ignored, and the PROGE bit in FSR to be set.
• KEY: Write protection key
This field should be written with the value 0xA5 to enable the command defined by the bits of the register. If the field is written
with a different value, the write is not performed and no action is started.
This field always reads as 0.
• PAGEN: Page number
The PAGEN field is used to address a page or fuse bit for certain operations. In order to simplify programming, the PAGEN field
is automatically updated every time the page buffer is written to. For every page buffer write, the PAGEN field is updated with the
page number of the address being written to. Hardware automatically masks writes to the PAGEN field so that only bits
representing valid page numbers can be written, all other bits in PAGEN are always 0. As an example, in a flash with 1024
pages (page 0 - page 1023), bits 15:10 will always be 0.
31 30 29 28 27 26 25 24
KEY
23 22 21 20 19 18 17 16
PAGEN [15:8]
15 14 13 12 11 10 9 8
PAGEN [7:0]
76543210
- - CMD
Table 9-7. Semantic of PAGEN field in different commands
Command PAGEN description
No operation Not used
Write Page The number of the page to write
Clear Page Buffer Not used
Lock region containing given Page Page number whose region should be locked
Unlock region containing given Page Page number whose region should be unlocked
Erase All Not used
Write General-Purpose Fuse Bit GPFUSE #
Erase General-Purpose Fuse Bit GPFUSE #
Set Security Bit Not used
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• CMD: Command
This field defines the flash command. Issuing any unused command will cause the Programming Error bit in FSR to be set, and
the corresponding interrupt to be requested if the PROGE bit in FCR is one.
Program GP Fuse Byte WriteData[7:0], ByteAddress[2:0]
Erase All GP Fuses Not used
Quick Page Read Page number
Write User Page Not used
Erase User Page Not used
Quick Page Read User Page Not used
High Speed Mode Enable Not used
High Speed Mode Disable Not used
Table 9-8. Set of commands
Command Value Mnemonic
No operation 0 NOP
Write Page 1 WP
Erase Page 2 EP
Clear Page Buffer 3 CPB
Lock region containing given Page 4 LP
Unlock region containing given Page 5 UP
Erase All 6 EA
Write General-Purpose Fuse Bit 7 WGPB
Erase General-Purpose Fuse Bit 8 EGPB
Set Security Bit 9 SSB
Program GP Fuse Byte 10 PGPFB
Erase All GPFuses 11 EAGPF
Quick Page Read 12 QPR
Write User Page 13 WUP
Erase User Page 14 EUP
Quick Page Read User Page 15 QPRUP
High Speed Mode Enable 16 HSEN
High Speed Mode Disable 17 HSDIS
RESERVED 16-31
Table 9-7. Semantic of PAGEN field in different commands
Command PAGEN description
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9.8.3 Flash Status Register
Name: FSR
Access Type: Read-only
Offset: 0x08
Reset Value: 0x00000000
• LOCKx: Lock Region x Lock Status
0: The corresponding lock region is not locked.
1: The corresponding lock region is locked.
• HSMODE: High-Speed Mode
0: High-speed mode disabled.
1: High-speed mode enabled.
• QPRR: Quick Page Read Result
0: The result is zero, i.e. the page is not erased.
1: The result is one, i.e. the page is erased.
• SECURITY: Security Bit Status
0: The security bit is inactive.
1: The security bit is active.
• PROGE: Programming Error Status
Automatically cleared when FSR is read.
0: No invalid commands and no bad keywords were written in the Flash Command Register FCMD.
1: An invalid command and/or a bad keyword was/were written in the Flash Command Register FCMD.
• LOCKE: Lock Error Status
Automatically cleared when FSR is read.
0: No programming of at least one locked lock region has happened since the last read of FSR.
1: Programming of at least one locked lock region has happened since the last read of FSR.
• FRDY: Flash Ready Status
0: The Flash Controller is busy and the application must wait before running a new command.
1: The Flash Controller is ready to run a new command.
31 30 29 28 27 26 25 24
LOCK15 LOCK14 LOCK13 LOCK12 LOCK11 LOCK10 LOCK9 LOCK8
23 22 21 20 19 18 17 16
LOCK7 LOCK6 LOCK5 LOCK4 LOCK3 LOCK2 LOCK1 LOCK0
15 14 13 12 11 10 9 8
--------
76543210
- HSMODE QPRR SECURITY PROGE LOCKE - FRDY
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9.8.4 Flash Parameter Register
Name: FPR
Access Type: Read-only
Offset: 0x0C
Reset Value: -
• PSZ: Page Size
The size of each flash page.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - PSZ
76543210
- - - - FSZ
Table 9-9. Flash Page Size
PSZ Page Size
0 32 Byte
1 64 Byte
2 128 Byte
3 256 Byte
4 512 Byte
5 1024 Byte
6 2048 Byte
7 4096 Byte
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• FSZ: Flash Size
The size of the flash. Not all device families will provide all flash sizes indicated in the table.
Table 9-10. Flash Size
FSZ Flash Size FSZ Flash Size
0 4 Kbyte 8 192 Kbyte
1 8 Kbyte 9 256 Kbyte
2 16 Kbyte 10 384 Kbyte
3 32 Kbyte 11 512 Kbyte
4 48 Kbyte 12 768 Kbyte
5 64 Kbyte 13 1024 Kbyte
6 96 Kbyte 14 2048 Kbyte
7 128 Kbyte 15 Reserved
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9.8.5 Flash Version Register
Name: FVR
Access Type: Read-only
Offset: 0x10
Reset Value: 0x00000000
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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9.8.6 Flash General Purpose Fuse Register High
Name: FGPFRHI
Access Type: Read-only
Offset: 0x14
Reset Value: -
This register is only used in systems with more than 32 GP fuses.
• GPFxx: General Purpose Fuse xx
0: The fuse has a written/programmed state.
1: The fuse has an erased state.
31 30 29 28 27 26 25 24
GPF63 GPF62 GPF61 GPF60 GPF59 GPF58 GPF57 GPF56
23 22 21 20 19 18 17 16
GPF55 GPF54 GPF53 GPF52 GPF51 GPF50 GPF49 GPF48
15 14 13 12 11 10 9 8
GPF47 GPF46 GPF45 GPF44 GPF43 GPF42 GPF41 GPF40
76543210
GPF39 GPF38 GPF37 GPF36 GPF35 GPF34 GPF33 GPF32
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9.8.7 Flash General Purpose Fuse Register Low
Name: FGPFRLO
Access Type: Read-only
Offset: 0x18
Reset Value: -
• GPFxx: General Purpose Fuse xx
0: The fuse has a written/programmed state.
1: The fuse has an erased state.
31 30 29 28 27 26 25 24
GPF31 GPF30 GPF29 GPF28 GPF27 GPF26 GPF25 GPF24
23 22 21 20 19 18 17 16
GPF23 GPF22 GPF21 GPF20 GPF19 GPF18 GPF17 GPF16
15 14 13 12 11 10 9 8
GPF15 GPF14 GPF13 GPF12 GPF11 GPF10 GPF09 GPF08
76543210
GPF07 GPF06 GPF05 GPF04 GPF03 GPF02 GPF01 GPF00
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9.9 Fuse Settings
The flash contains 32 general purpose fuses. These 32 fuses can be found in the Flash General
Purpose Fuse Register Low (FGPFRLO). The Flash General Purpose Fuse Register High
(FGPFRHI) is not used. In addition to the general purpose fuses, parts of the flash user page
can have a defined meaning outside of the flash controller and will also be described in this
section.
Note that when writing to the user page the values do not get loaded by the other modules on
the device until a chip reset occurs.
The general purpose fuses are erased by a JTAG or aWire chip erase.
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9.9.1 Flash General Purpose Fuse Register Low (FGPFRLO)
• BODEN: Brown Out Detector Enable
• BODHYST: Brown Out Detector Hysteresis
0: The Brown out detector hysteresis is disabled
1: The Brown out detector hysteresis is enabled
• BODLEVEL: Brown Out Detector Trigger Level
This controls the voltage trigger level for the Brown out detector. Refer to ”Electrical Characteristics” on page 897.
• UPROT, SECURE, BOOTPROT, EPFL, LOCK
These are Flash Controller fuses and are described in the FLASHCDW section.
9.9.1.1 Default Fuse Value
The devices are shipped with the FGPFRLO register value:0xE07FFFFF:
• BODEN fuses set to 11. BOD is disabled.
• BODHYST fuse set to 1. The BOD hysteresis is enabled.
• BODLEVEL fuses set to 000000. This is the minimum voltage trigger level for BOD. This level
is lower than the POR level, so when BOD is enabled, it will never trigger with this default
value.
• UPROT fuse set to 1.
• SECURE fuse set to 11.
• BOOTPROT fuses set to 111. The bootloader protection is disabled.
• EPFL fuse set to 1. External privileged fetch is not locked.
• LOCK fuses set to 1111111111111111. No region locked.
After the JTAG or aWire chip erase command, the FGPFR register value is 0xFFFFFFFF.
31 30 29 28 27 26 25 24
BODEN BODHYST BODLEVEL[5:1]
23 22 21 20 19 18 17 16
BODLEVEL[0] UPROT SECURE BOOTPROT EPFL
15 14 13 12 11 10 9 8
LOCK[15:8]
7 6543210
LOCK[7:0]
BODEN Description
00 BOD disabled
01 BOD enabled, BOD reset enabled
10 BOD enabled, BOD reset disabled
11 BOD disabled
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9.9.2 First Word of the User Page (Address 0x80800000)
• WDTAUTO: WatchDog Timer Auto Enable at Startup
0: The WDT is automatically enabled at startup.
1: The WDT is not automatically enabled at startup.
Please refer to the WDT chapter for detail about timeout settings when the WDT is automatically enabled.
9.9.2.1 Default user page first word value
The devices are shipped with the user page erased (all bits 1):
• WDTAUTO set to 1, WDT disabled.
31 30 29 28 27 26 25 24
- -------
23 22 21 20 19 18 17 16
- -------
15 14 13 12 11 10 9 8
- -------
7 6543210
- - - - - - - WDTAUTO
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9.9.3 Second Word of the User Page (Address 0x80800004)
• SSADRR: Secure State End Address for the RAM
• SSADRF: Secure State End Address for the Flash
9.9.3.1 Default user page second word value
The devices are shipped with the User page erased (all bits 1).
9.10 Serial Number
Each device has a unique 120 bits serial number readable from address 0x8080020C to
0x8080021A.
9.11 Module Configuration
The specific configuration for each FLASHCDW instance is listed in the following tables.The
module bus clocks listed here are connected to the system bus clocks. Please refer to the Power
Manager chapter for details.
31 30 29 28 27 26 25 24
SSADRR[15:8]
23 22 21 20 19 18 17 16
SSADRR[7:0]
15 14 13 12 11 10 9 8
SSADRF[15:8]
7 6543210
SSADRF[7:0]
Table 9-11. Module Configuration
Feature
ATUC256L3U,
ATUC256L4U
ATUC128L3U,
ATUC128L4U
ATUC64L3U,
ATUC64L4U
Flash size 256Kbytes 128Kbytes 64Kbytes
Number of pages 512 256 128
Page size 512 bytes 512 bytes 512 bytes
Table 9-12. Module Clock Name
Module Name Clock Name Description
FLASHCDW
CLK_FLASHCDW_HSB Clock for the FLASHCDW HSB interface
CLK_FLASHCDW_PB Clock for the FLASHCDW PB interface
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Table 9-13. Register Reset Values
Register
ATUC256L3U,
ATUC256L4U
ATUC128L3U,
ATUC128L4U
ATUC64L3U,
ATUC64L4U
FVR 0x00000120 0x00000120 0x00000120
FPR 0x00000409 0x00000407 0x00000405
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10. Secure Access Unit (SAU)
Rev: 1.1.1.3
10.1 Features
• Remaps registers in memory regions protected by the MPU to regions not protected by the MPU
• Programmable physical address for each channel
• Two modes of operation: Locked and Open
– In Locked Mode, access to a channel must be preceded by an unlock action
• An unlocked channel remains open only for a specific amount of time, if no access is
performed during this time, the channel is relocked
• Only one channel can be open at a time, opening a channel while another one is open
locks the first one
• Access to a locked channel is denied, a bus error and optionally an interrupt is returned
• If a channel is relocked due to an unlock timeout, an interrupt can optionally be
generated
– In Open Mode, all channels are permanently unlocked
10.2 Overview
In many systems, erroneous access to peripherals can lead to catastrophic failure. An example
of such a peripheral is the Pulse Width Modulator (PWM) used to control electric motors. The
PWM outputs a pulse train that controls the motor. If the control registers of the PWM module
are inadvertently updated with wrong values, the motor can start operating out of control, possibly
causing damage to the application and the surrounding environment. However, sometimes
the PWM control registers must be updated with new values, for example when modifying the
pulse train to accelerate the motor. A mechanism must be used to protect the PWM control registers
from inadvertent access caused by for example:
• Errors in the software code
• Transient errors in the CPU caused by for example electrical noise altering the execution path
of the program
To improve the security in a computer system, the AVR32UC implements a Memory Protection
Unit (MPU). The MPU can be set up to limit the accesses that can be performed to specific
memory addresses. The MPU divides the memory space into regions, and assigns a set of
access restrictions on each region. Access restrictions can for example be read/write if the CPU
is in supervisor mode, and read-only if the CPU is in application mode. The regions can be of different
size, but each region is usually quite large, e.g. protecting 1 kilobyte of address space or
more. Furthermore, access to each region is often controlled by the execution state of the CPU,
i.e. supervisor or application mode. Such a simple control mechanism is often too inflexible (too
coarse-grained chunks) and with too much overhead (often requiring system calls to access protected
memory locations) for simple or real-time systems such as embedded microcontrollers.
Usually, the Secure Access Unit (SAU) is used together with the MPU to provide the required
security and integrity. The MPU is set up to protect regions of memory, while the SAU is set up
to provide a secure channel into specific memory locations that are protected by the MPU.
These specific locations can be thought of as fine-grained overrides of the general coarsegrained
protection provided by the MPU.
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10.3 Block Diagram
Figure 10-1 presents the SAU integrated in an example system with a CPU, some memories,
some peripherals, and a bus system. The SAU is connected to both the Peripheral Bus (PB) and
the High Speed Bus (HSB). Configuration of the SAU is done via the PB, while memory
accesses are done via the HSB. The SAU receives an access on its HSB slave interface,
remaps it, checks that the channel is unlocked, and if so, initiates a transfer on its HSB master
interface to the remapped address.
The thin arrows in Figure 10-1 exemplifies control flow when using the SAU. The CPU wants to
read the RX Buffer in the USART. The MPU has been configured to protect all registers in the
USART from user mode access, while the SAU has been configured to remap the RX Buffer into
a memory space that is not protected by the MPU. This unprotected memory space is mapped
into the SAU HSB slave space. When the CPU reads the appropriate address in the SAU, the
SAU will perform an access to the desired RX buffer register in the USART, and thereafter return
the read results to the CPU. The return data flow will follow the opposite direction of the control
flow arrows in Figure 10-1.
Figure 10-1. SAU Block Diagram
SAU Channel
Bus master
MPU
CPU
Bus slave
USART
PWM
Bus slave Bus master
Bus slave
Flash
Bus slave
RAM
Bus bridge
SAU Configuration
Interrupt
request
High Speed Bus
SAU
Peripheral Bus
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10.4 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
10.4.1 Power Management
If the CPU enters a sleep mode that disables clocks used by the SAU, the SAU will stop functioning
and resume operation after the system wakes up from sleep mode.
10.4.2 Clocks
The SAU has two bus clocks connected: One High Speed Bus clock (CLK_SAU_HSB) and one
Peripheral Bus clock (CLK_SAU_PB). These clocks are generated by the Power Manager. Both
clocks are enabled at reset, and can be disabled by writing to the Power Manager. The user has
to ensure that CLK_SAU_HSB is not turned off before accessing the SAU. Likewise, the user
must ensure that no bus access is pending in the SAU before disabling CLK_SAU_HSB. Failing
to do so may deadlock the High Speed Bus.
10.4.3 Interrupt
The SAU interrupt request line is connected to the interrupt controller. Using the SAU interrupt
requires the interrupt controller to be programmed first.
10.4.4 Debug Operation
When an external debugger forces the CPU into debug mode, the SAU continues normal operation.
If the SAU is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
10.5 Functional Description
10.5.1 Enabling the SAU
The SAU is enabled by writing a one to the Enable (EN) bit in the Control Register (CR). This will
set the SAU Enabled (EN) bit in the Status Register (SR).
10.5.2 Configuring the SAU Channels
The SAU has a set of channels, mapped in the HSB memory space. These channels can be
configured by a Remap Target Register (RTR), located at the same memory address. When the
SAU is in normal mode, the SAU channel is addressed, and when the SAU is in setup mode, the
RTR can be addressed.
Before the SAU can be used, the channels must be configured and enabled. To configure a
channel, the corresponding RTR must be programmed with the Remap Target Address. To do
this, make sure the SAU is in setup mode by writing a one to the Setup Mode Enable (SEN) bit
in CR. This makes sure that a write to the RTR address accesses the RTR, not the SAU channel.
Thereafter, the RTR is written with the address to remap to, typically the address of a
specific PB register. When all channels have been configured, return to normal mode by writing
a one to the Setup Mode Disable (SDIS) in CR. The channels can now be enabled by writing
ones to the corresponding bits in the Channel Enable Registers (CERH/L).
The SAU is only able to remap addresses above 0xFFFC0000.
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10.5.2.1 Protecting SAU configuration registers
In order to prevent the SAU configuration registers to be changed by malicious or runaway code,
they should be protected by the MPU as soon as they have been configured. Maximum security
is provided in the system if program memory does not contain any code to unprotect the configuration
registers in the MPU. This guarantees that runaway code can not accidentally unprotect
and thereafter change the SAU configuration registers.
10.5.3 Lock Mechanism
The SAU can be configured to use two different access mechanisms: Open and Locked. In
Open Mode, SAU channels can be accessed freely after they have been configured and
enabled. In order to prevent accidental accesses to remapped addresses, it is possible to configure
the SAU in Locked Mode. Writing a one to the Open Mode bit in the CONFIG register
(CONFIG.OPEN) will enable Open Mode. Writing a zero to CONFIG.OPEN will enable Locked
Mode.
When using Locked Mode, the lock mechanism must be configured by writing a user defined key
value to the Unlock Key (UKEY) field in the Configuration Register (CONFIG). The number of
CLK_SAU_HSB cycles the channel remains unlocked must be written to the Unlock Number of
Clock Cycles (UCYC) field in CONFIG.
Access control to the SAU channels is enabled by means of the Unlock Register (UR), which
resides in the same address space as the SAU channels. Before a channel can be accessed,
the unlock register must be written with th correct key and channel number (single write access).
Access to the channel is then permitted for the next CONFIG.UCYC clock cycles, or until a successful
access to the unlocked channel has been made.
Only one channel can be unlocked at a time. If any other channel is unlocked at the time of writing
UR, this channel will be automatically locked before the channel addressed by the UR write
is unlocked.
An attempted access to a locked channel will be aborted, and the Channel Access Unsuccessful
bit (SR.CAU) will be set.
Any pending errors bits in SR must be cleared before it is possible to access UR. The following
SR bits are defined as error bits: EXP, CAU, URREAD, URKEY, URES, MBERROR, RTRADR.
If any of these bits are set while writing to UR, the write is aborted and the Unlock Register Error
Status (URES) bit in SR is set.
10.5.4 Normal Operation
The following sequence must be used in order to access a SAU channel in normal operation
(CR.SEN=0):
1. If not in Open Mode, write the unlock key to UR.KEY and the channel number to
UR.CHANNEL.
2. Perform the read or write operation to the SAU channel. If not in Open Mode, this must
be done within CONFIG.UCYC clock cycles of unlocking the channel. The SAU will use
its HSB master interface to remap the access to the target address pointed to by the
corresponding RTR.
3. To confirm that the access was successful, wait for the IDLE transfer status bit
(SR.IDLE) to indicate the operation is completed. Then check SR for possible error conditions.
The SAU can be configured to generate interrupt requests or a Bus Error
Exception if the access failed.
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10.5.4.1 Operation example
Figure 10-2 shows a typical memory map, consisting of some memories, some simple peripherals,
and a SAU with multiple channels and an Unlock Register (UR). Imagine that the MPU has
been set up to disallow all accesses from the CPU to the grey modules. Thus the CPU has no
way of accessing for example the Transmit Holding register in the UART, present on address X
on the bus. Note that the SAU RTRs are not protected by the MPU, thus the RTRs can be
accessed. If for example RTR0 is configured to point to address X, an access to RTR0 will be
remapped by the SAU to address X according to the algorithm presented above. By programming
the SAU RTRs, specific addresses in modules that have generally been protected by the
MPU can be performed.
Figure 10-2. Example Memory Map for a System with SAU
10.5.5 Interrupts
The SAU can generate an interrupt request to signal different events. All events that can generate
an interrupt request have dedicated bits in the Status Register (SR). An interrupt request will
be generated if the corresponding bit in the Interrupt Mask Register (IMR) is set. Bits in IMR are
set by writing a one to the corresponding bit in the Interrupt Enable Register (IER), and cleared
by writing a one to the corresponding bit in the Interrupt Disable Register (IDR). The interrupt
request remains active until the corresponding bit in SR is cleared by writing a one to the corresponding
bit in the Interrupt Clear Register (ICR).
The following SR bits are used for signalling the result of SAU accesses:
• RTR Address Error (RTRADR) is set if an illegal address is written to the RTRs. Only
addresses in the range 0xFFFC0000-0xFFFFFFFF are allowed.
• Master Interface Bus Error (MBERROR) is set if any of the conditions listed in Section 10.5.7
occurred.
Transmit Holding
Baudrate
Control
Receive Holding
Channel 1
RTR0
RTR1
Address X
Address Z
UART
SAU
CONFIG
SAU
CHANNEL
UR
RTR62 ...
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• Unlock Register Error Status (URES) is set if an attempt was made to unlock a channel by
writing to the Unlock Register while one or more error bits in SR were set (see Section
10.5.6). The unlock operation was aborted.
• Unlock Register Key Error (URKEY) is set if the Unlock Register was attempted written with
an invalid key.
• Unlock Register Read (URREAD) is set if the Unlock Register was attempted read.
• Channel Access Unsuccessful (CAU) is set if the channel access was unsuccessful.
• Channel Access Successful (CAS) is set if the channel access was successful.
• Channel Unlock Expired (EXP) is set if the channel lock expired, with no channel being
accessed after the channel was unlocked.
10.5.6 Error bits
If error bits are set when attempting to unlock a channel, SR.URES will be set. The following SR
bits are considered error bits:
• EXP
• CAU
• URREAD
• URKEY
• URES
• MBERROR
• RTRADR
10.5.7 Bus Error Responses
By writing a one to the Bus Error Response Enable bit (CR.BERREN), serious access errors will
be configured to return a bus error to the CPU. This will cause the CPU to execute its Bus Error
Data Fetch exception routine.
The conditions that can generate a bus error response are:
• Reading the Unlock Register
• Trying to access a locked channel
• The SAU HSB master receiving a bus error response from its addressed slave
10.5.8 Disabling the SAU
To disable the SAU, the user must first ensure that no SAU bus operations are pending. This
can be done by checking that the SR.IDLE bit is set.
The SAU may then be disabled by writing a one to the Disable (DIS) bit in CR.
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10.6 User Interface
The following addresses are used by SAU channel configuration registers. All offsets are relative to the SAU’s PB base
address.
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
The following addresses are used by SAU channel registers. All offsets are relative to the SAU’s HSB base address. The
number of channels implemented is device specific, refer to the Module Configuration section at the end of this chapter.
Table 10-1. SAU Configuration Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Write-only 0x00000000
0x04 Configuration Register CONFIG Write-only 0x00000000
0x08 Channel Enable Register High CERH Read/Write 0x00000000
0x0C Channel Enable Register Low CERL Read/Write 0x00000000
0x10 Status Register SR Read-only 0x00000400
0x14 Interrupt Enable Register IER Write-only 0x00000000
0x18 Interrupt Disable Register IDR Write-only 0x00000000
0x1C Interrupt Mask Register IMR Read-only 0x00000000
0x20 Interrupt Clear Register ICR Write-only 0x00000000
0x24 Parameter Register PARAMETER Read-only -(1)
0x28 Version Register VERSION Read-only -(1)
Table 10-2. SAU Channel Register Memory Map
Offset Register Register Name Access Reset
0x00 Remap Target Register 0 RTR0 Read/Write N/A
0x04 Remap Target Register 1 RTR1 Read/Write N/A
0x08 Remap Target Register 2 RTR2 Read/Write N/A
... ... ... ... ...
0x04*n Remap Target Register n RTRn Read/Write N/A
0xFC Unlock Register UR Write-only N/A
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10.6.1 Control Register
Name: CR
Access Type: Write-only
Offset: 0x00
Reset Value: 0x00000000
• BERRDIS: Bus Error Response Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables Bus Error Response from the SAU.
• BERREN: Bus Error Response Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables Bus Error Response from the SAU.
• SDIS: Setup Mode Disable
Writing a zero to this bit has no effect.
Writing a one to this bit exits setup mode.
• SEN: Setup Mode Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enters setup mode.
• DIS: SAU Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the SAU.
• EN: SAU Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the SAU.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - BERRDIS BERREN SDIS SEN DIS EN
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10.6.2 Configuration Register
Name: CONFIG
Access Type: Write-only
Offset: 0x04
Reset Value: 0x00000000
• OPEN: Open Mode Enable
Writing a zero to this bit disables open mode.
Writing a one to this bit enables open mode.
• UCYC: Unlock Number of Clock Cycles
Once a channel has been unlocked, it remains unlocked for this amount of CLK_SAU_HSB clock cycles or until one access to a
channel has been made.
• UKEY: Unlock Key
The value in this field must be written to UR.KEY to unlock a channel.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - OPEN
15 14 13 12 11 10 9 8
UCYC
76543210
UKEY
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10.6.3 Channel Enable Register High
Name: CERH
Access Type: Read/Write
Offset: 0x08
Reset Value: 0x00000000
• CERH[n]: Channel Enable Register High
0: Channel (n+32) is not enabled.
1: Channel (n+32) is enabled.
31 30 29 28 27 26 25 24
- CERH[30:24]
23 22 21 20 19 18 17 16
CERH[23:16]
15 14 13 12 11 10 9 8
CERH[15:8]
76543210
CERH[7:0]
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10.6.4 Channel Enable Register Low
Name: CERL
Access Type: Read/Write
Offset: 0x0C
Reset Value: 0x00000000
• CERL[n]: Channel Enable Register Low
0: Channel n is not enabled.
1: Channel n is enabled.
31 30 29 28 27 26 25 24
CERL[31:24]
23 22 21 20 19 18 17 16
CERL[23:16]
15 14 13 12 11 10 9 8
CERL[15:8]
76543210
CERL[7:0]
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10.6.5 Status Register
Name: SR
Access Type: Read-only
Offset: 0x10
Reset Value: 0x00000400
• IDLE
This bit is cleared when a read or write operation to the SAU channel is started.
This bit is set when the operation is completed and no SAU bus operations are pending.
• SEN: SAU Setup Mode Enable
This bit is cleared when the SAU exits setup mode.
This bit is set when the SAU enters setup mode.
• EN: SAU Enabled
This bit is cleared when the SAU is disabled.
This bit is set when the SAU is enabled.
• RTRADR: RTR Address Error
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if, in the configuration phase, an RTR was written with an illegal address, i.e. the upper 16 bits in the address were
different from 0xFFFC, 0xFFFD, 0xFFFE or 0xFFFF.
• MBERROR: Master Interface Bus Error
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if a channel access generated a transfer on the master interface that received a bus error response from the
addressed slave.
• URES: Unlock Register Error Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if an attempt was made to unlock a channel by writing to the Unlock Register while one or more error bits were set
in SR. The unlock operation was aborted.
• URKEY: Unlock Register Key Error
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if the Unlock Register was attempted written with an invalid key.
• URREAD: Unlock Register Read
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if the Unlock Register was read.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - IDLE SEN EN
76543210
RTRADR MBERROR URES URKEY URREAD CAU CAS EXP
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• CAU: Channel Access Unsuccessful
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if channel access was unsuccessful, i.e. an access was attempted to a locked or disabled channel.
• CAS: Channel Access Successful
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if channel access successful, i.e. one access was made after the channel was unlocked.
• EXP: Channel Unlock Expired
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set if channel unlock has expired, i.e. no access being made after the channel was unlocked.
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10.6.6 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RTRADR MBERROR URES URKEY URREAD CAU CAS EXP
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10.6.7 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x18
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RTRADR MBERROR URES URKEY URREAD CAU CAS EXP
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10.6.8 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RTRADR MBERROR URES URKEY URREAD CAU CAS EXP
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10.6.9 Interrupt Clear Register
Name: ICR
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and any corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RTRADR MBERROR URES URKEY URREAD CAU CAS EXP
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10.6.10 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x24
Reset Value: -
• CHANNELS:
Number of channels implemented.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CHANNELS
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10.6.11 Version Register
Name: VERSION
Access Type: Write-only
Offset: 0x28
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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10.6.12 Remap Target Register n
Name: RTRn
Access Type: Read/Write
Offset: n*4
Reset Value: 0x00000000
• RTR: Remap Target Address for Channel n
RTR[31:16] must have one of the following values, any other value will result in UNDEFINED behavior:
0xFFFC
0xFFFD
0xFFFE
0xFFFF
RTR[1:0] must be written to 00, any other value will result in UNDEFINED behavior.
31 30 29 28 27 26 25 24
RTR[31:24]
23 22 21 20 19 18 17 16
RTR[23:16]
15 14 13 12 11 10 9 8
RTR[15:8]
76543210
RTR[7:0]
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10.6.13 Unlock Register
Name: UR
Access Type : Write-only
Offset: 0xFC
Reset Value: 0x00000000
• KEY: Unlock Key
The correct key must be written in order to unlock a channel. The key value written must correspond to the key value defined in
CONFIG.UKEY.
• CHANNEL: Channel Number
Number of the channel to unlock.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
KEY
76543210
- - CHANNEL
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10.7 Module Configuration
The specific configuration for each SAU instance is listed in the following tables.The module bus
clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 10-3. SAU configuration
Feature SAU
SAU Channels 16
Table 10-4. SAU clock name
Module name Clock name Description
SAU CLK_SAU_HSB Clock for the SAU HSB interface
SAU CLK_SAU_PB Clock for the SAU PB interface
Table 10-5. Register Reset Values
Register Reset Value
VERSION 0x00000111
PARAMETER 0x00000010
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11. HSB Bus Matrix (HMATRIXB)
Rev: 1.3.0.3
11.1 Features
• User Interface on peripheral bus
• Configurable number of masters (up to 16)
• Configurable number of slaves (up to 16)
• One decoder for each master
• Programmable arbitration for each slave
– Round-Robin
– Fixed priority
• Programmable default master for each slave
– No default master
– Last accessed default master
– Fixed default master
• One cycle latency for the first access of a burst
• Zero cycle latency for default master
• One special function register for each slave (not dedicated)
11.2 Overview
The Bus Matrix implements a multi-layer bus structure, that enables parallel access paths
between multiple High Speed Bus (HSB) masters and slaves in a system, thus increasing the
overall bandwidth. The Bus Matrix interconnects up to 16 HSB Masters to up to 16 HSB Slaves.
The normal latency to connect a master to a slave is one cycle except for the default master of
the accessed slave which is connected directly (zero cycle latency). The Bus Matrix provides 16
Special Function Registers (SFR) that allow the Bus Matrix to support application specific
features.
11.3 Product Dependencies
In order to configure this module by accessing the user registers, other parts of the system must
be configured correctly, as described below.
11.3.1 Clocks
The clock for the HMATRIX bus interface (CLK_HMATRIX) is generated by the Power Manager.
This clock is enabled at reset, and can be disabled in the Power Manager.
11.4 Functional Description
11.4.1 Special Bus Granting Mechanism
The Bus Matrix provides some speculative bus granting techniques in order to anticipate access
requests from some masters. This mechanism reduces latency at first access of a burst or single
transfer. This bus granting mechanism sets a different default master for every slave.
At the end of the current access, if no other request is pending, the slave remains connected to
its associated default master. A slave can be associated with three kinds of default masters: no
default master, last access master, and fixed default master.
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To change from one kind of default master to another, the Bus Matrix user interface provides the
Slave Configuration Registers, one for each slave, that set a default master for each slave. The
Slave Configuration Register contains two fields: DEFMSTR_TYPE and FIXED_DEFMSTR. The
2-bit DEFMSTR_TYPE field selects the default master type (no default, last access master, fixed
default master), whereas the 4-bit FIXED_DEFMSTR field selects a fixed default master provided
that DEFMSTR_TYPE is set to fixed default master. Please refer to the Bus Matrix user
interface description.
11.4.1.1 No Default Master
At the end of the current access, if no other request is pending, the slave is disconnected from
all masters. No Default Master suits low-power mode.
11.4.1.2 Last Access Master
At the end of the current access, if no other request is pending, the slave remains connected to
the last master that performed an access request.
11.4.1.3 Fixed Default Master
At the end of the current access, if no other request is pending, the slave connects to its fixed
default master. Unlike last access master, the fixed master does not change unless the user
modifies it by a software action (field FIXED_DEFMSTR of the related SCFG).
11.4.2 Arbitration
The Bus Matrix provides an arbitration mechanism that reduces latency when conflict cases
occur, i.e. when two or more masters try to access the same slave at the same time. One arbiter
per HSB slave is provided, thus arbitrating each slave differently.
The Bus Matrix provides the user with the possibility of choosing between 2 arbitration types for
each slave:
1. Round-Robin Arbitration (default)
2. Fixed Priority Arbitration
This is selected by the ARBT field in the Slave Configuration Registers (SCFG).
Each algorithm may be complemented by selecting a default master configuration for each
slave.
When a re-arbitration must be done, specific conditions apply. This is described in “Arbitration
Rules” .
11.4.2.1 Arbitration Rules
Each arbiter has the ability to arbitrate between two or more different master requests. In order
to avoid burst breaking and also to provide the maximum throughput for slave interfaces, arbitration
may only take place during the following cycles:
1. Idle Cycles: When a slave is not connected to any master or is connected to a master
which is not currently accessing it.
2. Single Cycles: When a slave is currently doing a single access.
3. End of Burst Cycles: When the current cycle is the last cycle of a burst transfer. For
defined length burst, predicted end of burst matches the size of the transfer but is managed
differently for undefined length burst. This is described below.
4. Slot Cycle Limit: When the slot cycle counter has reached the limit value indicating that
the current master access is too long and must be broken. This is described below.
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• Undefined Length Burst Arbitration
In order to avoid long slave handling during undefined length bursts (INCR), the Bus Matrix provides
specific logic in order to re-arbitrate before the end of the INCR transfer. A predicted end
of burst is used as a defined length burst transfer and can be selected among the following five
possibilities:
1. Infinite: No predicted end of burst is generated and therefore INCR burst transfer will
never be broken.
2. One beat bursts: Predicted end of burst is generated at each single transfer inside the
INCP transfer.
3. Four beat bursts: Predicted end of burst is generated at the end of each four beat
boundary inside INCR transfer.
4. Eight beat bursts: Predicted end of burst is generated at the end of each eight beat
boundary inside INCR transfer.
5. Sixteen beat bursts: Predicted end of burst is generated at the end of each sixteen beat
boundary inside INCR transfer.
This selection can be done through the ULBT field in the Master Configuration Registers
(MCFG).
• Slot Cycle Limit Arbitration
The Bus Matrix contains specific logic to break long accesses, such as very long bursts on a
very slow slave (e.g., an external low speed memory). At the beginning of the burst access, a
counter is loaded with the value previously written in the SLOT_CYCLE field of the related Slave
Configuration Register (SCFG) and decreased at each clock cycle. When the counter reaches
zero, the arbiter has the ability to re-arbitrate at the end of the current byte, halfword, or word
transfer.
11.4.2.2 Round-Robin Arbitration
This algorithm allows the Bus Matrix arbiters to dispatch the requests from different masters to
the same slave in a round-robin manner. If two or more master requests arise at the same time,
the master with the lowest number is first serviced, then the others are serviced in a round-robin
manner.
There are three round-robin algorithms implemented:
1. Round-Robin arbitration without default master
2. Round-Robin arbitration with last default master
3. Round-Robin arbitration with fixed default master
• Round-Robin Arbitration without Default Master
This is the main algorithm used by Bus Matrix arbiters. It allows the Bus Matrix to dispatch
requests from different masters to the same slave in a pure round-robin manner. At the end of
the current access, if no other request is pending, the slave is disconnected from all masters.
This configuration incurs one latency cycle for the first access of a burst. Arbitration without
default master can be used for masters that perform significant bursts.
• Round-Robin Arbitration with Last Default Master
This is a biased round-robin algorithm used by Bus Matrix arbiters. It allows the Bus Matrix to
remove the one latency cycle for the last master that accessed the slave. At the end of the cur-
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rent transfer, if no other master request is pending, the slave remains connected to the last
master that performed the access. Other non privileged masters still get one latency cycle if they
want to access the same slave. This technique can be used for masters that mainly perform single
accesses.
• Round-Robin Arbitration with Fixed Default Master
This is another biased round-robin algorithm. It allows the Bus Matrix arbiters to remove the one
latency cycle for the fixed default master per slave. At the end of the current access, the slave
remains connected to its fixed default master. Every request attempted by this fixed default master
will not cause any latency whereas other non privileged masters will still get one latency
cycle. This technique can be used for masters that mainly perform single accesses.
11.4.2.3 Fixed Priority Arbitration
This algorithm allows the Bus Matrix arbiters to dispatch the requests from different masters to
the same slave by using the fixed priority defined by the user. If two or more master requests are
active at the same time, the master with the highest priority number is serviced first. If two or
more master requests with the same priority are active at the same time, the master with the
highest number is serviced first.
For each slave, the priority of each master may be defined through the Priority Registers for
Slaves (PRAS and PRBS).
11.4.3 Slave and Master assignation
The index number assigned to Bus Matrix slaves and masters are described in the Module Configuration
section at the end of this chapter.
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11.5 User Interface
Table 11-1. HMATRIX Register Memory Map
Offset Register Name Access Reset Value
0x0000 Master Configuration Register 0 MCFG0 Read/Write 0x00000002
0x0004 Master Configuration Register 1 MCFG1 Read/Write 0x00000002
0x0008 Master Configuration Register 2 MCFG2 Read/Write 0x00000002
0x000C Master Configuration Register 3 MCFG3 Read/Write 0x00000002
0x0010 Master Configuration Register 4 MCFG4 Read/Write 0x00000002
0x0014 Master Configuration Register 5 MCFG5 Read/Write 0x00000002
0x0018 Master Configuration Register 6 MCFG6 Read/Write 0x00000002
0x001C Master Configuration Register 7 MCFG7 Read/Write 0x00000002
0x0020 Master Configuration Register 8 MCFG8 Read/Write 0x00000002
0x0024 Master Configuration Register 9 MCFG9 Read/Write 0x00000002
0x0028 Master Configuration Register 10 MCFG10 Read/Write 0x00000002
0x002C Master Configuration Register 11 MCFG11 Read/Write 0x00000002
0x0030 Master Configuration Register 12 MCFG12 Read/Write 0x00000002
0x0034 Master Configuration Register 13 MCFG13 Read/Write 0x00000002
0x0038 Master Configuration Register 14 MCFG14 Read/Write 0x00000002
0x003C Master Configuration Register 15 MCFG15 Read/Write 0x00000002
0x0040 Slave Configuration Register 0 SCFG0 Read/Write 0x00000010
0x0044 Slave Configuration Register 1 SCFG1 Read/Write 0x00000010
0x0048 Slave Configuration Register 2 SCFG2 Read/Write 0x00000010
0x004C Slave Configuration Register 3 SCFG3 Read/Write 0x00000010
0x0050 Slave Configuration Register 4 SCFG4 Read/Write 0x00000010
0x0054 Slave Configuration Register 5 SCFG5 Read/Write 0x00000010
0x0058 Slave Configuration Register 6 SCFG6 Read/Write 0x00000010
0x005C Slave Configuration Register 7 SCFG7 Read/Write 0x00000010
0x0060 Slave Configuration Register 8 SCFG8 Read/Write 0x00000010
0x0064 Slave Configuration Register 9 SCFG9 Read/Write 0x00000010
0x0068 Slave Configuration Register 10 SCFG10 Read/Write 0x00000010
0x006C Slave Configuration Register 11 SCFG11 Read/Write 0x00000010
0x0070 Slave Configuration Register 12 SCFG12 Read/Write 0x00000010
0x0074 Slave Configuration Register 13 SCFG13 Read/Write 0x00000010
0x0078 Slave Configuration Register 14 SCFG14 Read/Write 0x00000010
0x007C Slave Configuration Register 15 SCFG15 Read/Write 0x00000010
0x0080 Priority Register A for Slave 0 PRAS0 Read/Write 0x00000000
0x0084 Priority Register B for Slave 0 PRBS0 Read/Write 0x00000000
0x0088 Priority Register A for Slave 1 PRAS1 Read/Write 0x00000000
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0x008C Priority Register B for Slave 1 PRBS1 Read/Write 0x00000000
0x0090 Priority Register A for Slave 2 PRAS2 Read/Write 0x00000000
0x0094 Priority Register B for Slave 2 PRBS2 Read/Write 0x00000000
0x0098 Priority Register A for Slave 3 PRAS3 Read/Write 0x00000000
0x009C Priority Register B for Slave 3 PRBS3 Read/Write 0x00000000
0x00A0 Priority Register A for Slave 4 PRAS4 Read/Write 0x00000000
0x00A4 Priority Register B for Slave 4 PRBS4 Read/Write 0x00000000
0x00A8 Priority Register A for Slave 5 PRAS5 Read/Write 0x00000000
0x00AC Priority Register B for Slave 5 PRBS5 Read/Write 0x00000000
0x00B0 Priority Register A for Slave 6 PRAS6 Read/Write 0x00000000
0x00B4 Priority Register B for Slave 6 PRBS6 Read/Write 0x00000000
0x00B8 Priority Register A for Slave 7 PRAS7 Read/Write 0x00000000
0x00BC Priority Register B for Slave 7 PRBS7 Read/Write 0x00000000
0x00C0 Priority Register A for Slave 8 PRAS8 Read/Write 0x00000000
0x00C4 Priority Register B for Slave 8 PRBS8 Read/Write 0x00000000
0x00C8 Priority Register A for Slave 9 PRAS9 Read/Write 0x00000000
0x00CC Priority Register B for Slave 9 PRBS9 Read/Write 0x00000000
0x00D0 Priority Register A for Slave 10 PRAS10 Read/Write 0x00000000
0x00D4 Priority Register B for Slave 10 PRBS10 Read/Write 0x00000000
0x00D8 Priority Register A for Slave 11 PRAS11 Read/Write 0x00000000
0x00DC Priority Register B for Slave 11 PRBS11 Read/Write 0x00000000
0x00E0 Priority Register A for Slave 12 PRAS12 Read/Write 0x00000000
0x00E4 Priority Register B for Slave 12 PRBS12 Read/Write 0x00000000
0x00E8 Priority Register A for Slave 13 PRAS13 Read/Write 0x00000000
0x00EC Priority Register B for Slave 13 PRBS13 Read/Write 0x00000000
0x00F0 Priority Register A for Slave 14 PRAS14 Read/Write 0x00000000
0x00F4 Priority Register B for Slave 14 PRBS14 Read/Write 0x00000000
0x00F8 Priority Register A for Slave 15 PRAS15 Read/Write 0x00000000
0x00FC Priority Register B for Slave 15 PRBS15 Read/Write 0x00000000
0x0110 Special Function Register 0 SFR0 Read/Write –
0x0114 Special Function Register 1 SFR1 Read/Write –
0x0118 Special Function Register 2 SFR2 Read/Write –
0x011C Special Function Register 3 SFR3 Read/Write –
0x0120 Special Function Register 4 SFR4 Read/Write –
0x0124 Special Function Register 5 SFR5 Read/Write –
0x0128 Special Function Register 6 SFR6 Read/Write –
Table 11-1. HMATRIX Register Memory Map (Continued)
Offset Register Name Access Reset Value
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0x012C Special Function Register 7 SFR7 Read/Write –
0x0130 Special Function Register 8 SFR8 Read/Write –
0x0134 Special Function Register 9 SFR9 Read/Write –
0x0138 Special Function Register 10 SFR10 Read/Write –
0x013C Special Function Register 11 SFR11 Read/Write –
0x0140 Special Function Register 12 SFR12 Read/Write –
0x0144 Special Function Register 13 SFR13 Read/Write –
0x0148 Special Function Register 14 SFR14 Read/Write –
0x014C Special Function Register 15 SFR15 Read/Write –
Table 11-1. HMATRIX Register Memory Map (Continued)
Offset Register Name Access Reset Value
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11.5.1 Master Configuration Registers
Name: MCFG0...MCFG15
Access Type: Read/Write
Offset: 0x00 - 0x3C
Reset Value: 0x00000002
• ULBT: Undefined Length Burst Type
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
––––––––
15 14 13 12 11 10 9 8
––––––––
76543210
– – – – – ULBT
Table 11-2. Undefined Length Burst Type
ULBT Undefined Length Burst Type Description
000 Inifinite Length Burst No predicted end of burst is generated and therefore INCR bursts coming from this
master cannot be broken.
001 Single-Access The undefined length burst is treated as a succession of single accesses, allowing rearbitration
at each beat of the INCR burst.
010 4 Beat Burst The undefined length burst is split into a four-beat burst, allowing re-arbitration at each
four-beat burst end.
011 8 Beat Burst The undefined length burst is split into an eight-beat burst, allowing re-arbitration at
each eight-beat burst end.
100 16 Beat Burst The undefined length burst is split into a sixteen-beat burst, allowing re-arbitration at
each sixteen-beat burst end.
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11.5.2 Slave Configuration Registers
Name: SCFG0...SCFG15
Access Type: Read/Write
Offset: 0x40 - 0x7C
Reset Value: 0x00000010
• ARBT: Arbitration Type
0: Round-Robin Arbitration
1: Fixed Priority Arbitration
• FIXED_DEFMSTR: Fixed Default Master
This is the number of the Default Master for this slave. Only used if DEFMSTR_TYPE is 2. Specifying the number of a master
which is not connected to the selected slave is equivalent to setting DEFMSTR_TYPE to 0.
• DEFMSTR_TYPE: Default Master Type
0: No Default Master
At the end of the current slave access, if no other master request is pending, the slave is disconnected from all masters.
This results in a one cycle latency for the first access of a burst transfer or for a single access.
1: Last Default Master
At the end of the current slave access, if no other master request is pending, the slave stays connected to the last master having
accessed it.
This results in not having one cycle latency when the last master tries to access the slave again.
2: Fixed Default Master
At the end of the current slave access, if no other master request is pending, the slave connects to the fixed master the number
that has been written in the FIXED_DEFMSTR field.
This results in not having one cycle latency when the fixed master tries to access the slave again.
• SLOT_CYCLE: Maximum Number of Allowed Cycles for a Burst
When the SLOT_CYCLE limit is reached for a burst, it may be broken by another master trying to access this slave.
This limit has been placed to avoid locking a very slow slave when very long bursts are used.
This limit must not be very small. Unreasonably small values break every burst and the Bus Matrix arbitrates without performing
any data transfer. 16 cycles is a reasonable value for SLOT_CYCLE.
31 30 29 28 27 26 25 24
– – – – – – – ARBT
23 22 21 20 19 18 17 16
– – FIXED_DEFMSTR DEFMSTR_TYPE
15 14 13 12 11 10 9 8
––––––––
76543210
SLOT_CYCLE
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11.5.3 Bus Matrix Priority Registers A For Slaves
Register Name: PRAS0...PRAS15
Access Type: Read/Write
Offset: -
Reset Value: 0x00000000
• MxPR: Master x Priority
Fixed priority of Master x for accessing the selected slave. The higher the number, the higher the priority.
31 30 29 28 27 26 25 24
- - M7PR - - M6PR
23 22 21 20 19 18 17 16
- - M5PR - - M4PR
15 14 13 12 11 10 9 8
- - M3PR - - M2PR
76543210
- - M1PR - - M0PR
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11.5.4 Priority Registers B For Slaves
Name: PRBS0...PRBS15
Access Type: Read/Write
Offset: -
Reset Value: 0x00000000
• MxPR: Master x Priority
Fixed priority of Master x for accessing the selected slave. The higher the number, the higher the priority.
31 30 29 28 27 26 25 24
- - M15PR - - M14PR
23 22 21 20 19 18 17 16
- - M13PR - - M12PR
15 14 13 12 11 10 9 8
- - M11PR - - M10PR
76543210
- - M9PR - - M8PR
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11.5.5 Special Function Registers
Name: SFR0...SFR15
Access Type: Read/Write
Offset: 0x110 - 0x14C
Reset Value: -
• SFR: Special Function Register Fields
Those registers are not a HMATRIX specific register. The field of those will be defined where they are used.
31 30 29 28 27 26 25 24
SFR
23 22 21 20 19 18 17 16
SFR
15 14 13 12 11 10 9 8
SFR
76543210
SFR
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11.6 Module Configuration
The specific configuration for each HMATRIX instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power
Manager chapter for details.
11.6.1 Bus Matrix Connections
The bus matrix has the several masters and slaves. Each master has its own bus and its own
decoder, thus allowing a different memory mapping per master. The master number in the table
below can be used to index the HMATRIX control registers. For example, HMATRIX MCFG0
register is associated with the CPU Data master interface.
Each slave has its own arbiter, thus allowing a different arbitration per slave. The slave number
in the table below can be used to index the HMATRIX control registers. For example, SCFG3 is
associated with the Internal SRAM Slave Interface.
Accesses to unused areas returns an error result to the master requesting such an access.
Table 11-3. HMATRIX Clocks
Clock Name Description
CLK_HMATRIX Clock for the HMATRIX bus interface
Table 11-4. High Speed Bus Masters
Master 0 CPU Data
Master 1 CPU Instruction
Master 2 CPU SAB
Master 3 SAU
Master 4 PDCA
Master 5 USBC
Table 11-5. High Speed Bus Slaves
Slave 0 Internal Flash
Slave 1 HSB-PB Bridge A
Slave 2 HSB-PB Bridge B
Slave 3 Internal SRAM
Slave 4 SAU
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Figure 11-1. HMatrix Master / Slave Connections
CPU Data 0
CPU
Instruction 1
CPU SAB 2
SAU 3
Internal Flash
0
HSB-PB
Bridge 0
1
HSB-PB
Bridge 1
2
Internal SRAM
3
HMATRIX SLAVES
HMATRIX MASTERS
SAU
4
PDCA 4
USBC 5
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12. Interrupt Controller (INTC)
Rev: 1.0.2.5
12.1 Features
• Autovectored low latency interrupt service with programmable priority
– 4 priority levels for regular, maskable interrupts
– One Non-Maskable Interrupt
• Up to 64 groups of interrupts with up to 32 interrupt requests in each group
12.2 Overview
The INTC collects interrupt requests from the peripherals, prioritizes them, and delivers an interrupt
request and an autovector to the CPU. The AVR32 architecture supports 4 priority levels for
regular, maskable interrupts, and a Non-Maskable Interrupt (NMI).
The INTC supports up to 64 groups of interrupts. Each group can have up to 32 interrupt request
lines, these lines are connected to the peripherals. Each group has an Interrupt Priority Register
(IPR) and an Interrupt Request Register (IRR). The IPRs are used to assign a priority level and
an autovector to each group, and the IRRs are used to identify the active interrupt request within
each group. If a group has only one interrupt request line, an active interrupt group uniquely
identifies the active interrupt request line, and the corresponding IRR is not needed. The INTC
also provides one Interrupt Cause Register (ICR) per priority level. These registers identify the
group that has a pending interrupt of the corresponding priority level. If several groups have a
pending interrupt of the same level, the group with the lowest number takes priority.
12.3 Block Diagram
Figure 12-1 gives an overview of the INTC. The grey boxes represent registers that can be
accessed via the user interface. The interrupt requests from the peripherals (IREQn) and the
NMI are input on the left side of the figure. Signals to and from the CPU are on the right side of
the figure.
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Figure 12-1. INTC Block Diagram
12.4 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
12.4.1 Power Management
If the CPU enters a sleep mode that disables CLK_SYNC, the INTC will stop functioning and
resume operation after the system wakes up from sleep mode.
12.4.2 Clocks
The clock for the INTC bus interface (CLK_INTC) is generated by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager.
The INTC sampling logic runs on a clock which is stopped in any of the sleep modes where the
system RC oscillator is not running. This clock is referred to as CLK_SYNC. This clock is
enabled at reset, and only turned off in sleep modes where the system RC oscillator is stopped.
12.4.3 Debug Operation
When an external debugger forces the CPU into debug mode, the INTC continues normal
operation.
12.5 Functional Description
All of the incoming interrupt requests (IREQs) are sampled into the corresponding Interrupt
Request Register (IRR). The IRRs must be accessed to identify which IREQ within a group that
is active. If several IREQs within the same group are active, the interrupt service routine must
prioritize between them. All of the input lines in each group are logically ORed together to form
the GrpReqN lines, indicating if there is a pending interrupt in the corresponding group.
The Request Masking hardware maps each of the GrpReq lines to a priority level from INT0 to
INT3 by associating each group with the Interrupt Level (INTLEVEL) field in the corresponding
Request
Masking
OR
IREQ0
IREQ1
IREQ2
IREQ31
GrpReq0
Masks SREG
Masks
I[3-0]M
GM
INTLEVEL
AUTOVECTOR
Prioritizer
Interrupt Controller CPU
OR GrpReqN
NMIREQ
OR
IREQ32
IREQ33
IREQ34
IREQ63
GrpReq1
IRR Registers IPR Registers ICR Registers
INT_level,
offset
INT_level,
offset
INT_level,
offset
IPR0
IPR1
IPRn
IRR0
IRR1
IRRn
ValReq0
ValReq1
ValReqN
.
.
.
.
.
.
.
.
.
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Interrupt Priority Register (IPR). The GrpReq inputs are then masked by the mask bits from the
CPU status register. Any interrupt group that has a pending interrupt of a priority level that is not
masked by the CPU status register, gets its corresponding ValReq line asserted.
Masking of the interrupt requests is done based on five interrupt mask bits of the CPU status
register, namely Interrupt Level 3 Mask (I3M) to Interrupt Level 0 Mask (I0M), and Global Interrupt
Mask (GM). An interrupt request is masked if either the GM or the corresponding interrupt
level mask bit is set.
The Prioritizer hardware uses the ValReq lines and the INTLEVEL field in the IPRs to select the
pending interrupt of the highest priority. If an NMI interrupt request is pending, it automatically
gets the highest priority of any pending interrupt. If several interrupt groups of the highest pending
interrupt level have pending interrupts, the interrupt group with the lowest number is
selected.
The INTLEVEL and handler autovector offset (AUTOVECTOR) of the selected interrupt are
transmitted to the CPU for interrupt handling and context switching. The CPU does not need to
know which interrupt is requesting handling, but only the level and the offset of the handler
address. The IRR registers contain the interrupt request lines of the groups and can be read via
user interface registers for checking which interrupts of the group are actually active.
The delay through the INTC from the peripheral interrupt request is set until the interrupt request
to the CPU is set is three cycles of CLK_SYNC.
12.5.1 Non-Maskable Interrupts
A NMI request has priority over all other interrupt requests. NMI has a dedicated exception vector
address defined by the AVR32 architecture, so AUTOVECTOR is undefined when
INTLEVEL indicates that an NMI is pending.
12.5.2 CPU Response
When the CPU receives an interrupt request it checks if any other exceptions are pending. If no
exceptions of higher priority are pending, interrupt handling is initiated. When initiating interrupt
handling, the corresponding interrupt mask bit is set automatically for this and lower levels in status
register. E.g, if an interrupt of level 3 is approved for handling, the interrupt mask bits I3M,
I2M, I1M, and I0M are set in status register. If an interrupt of level 1 is approved, the masking
bits I1M and I0M are set in status register. The handler address is calculated by logical OR of
the AUTOVECTOR to the CPU system register Exception Vector Base Address (EVBA). The
CPU will then jump to the calculated address and start executing the interrupt handler.
Setting the interrupt mask bits prevents the interrupts from the same and lower levels to be
passed through the interrupt controller. Setting of the same level mask bit prevents also multiple
requests of the same interrupt to happen.
It is the responsibility of the handler software to clear the interrupt request that caused the interrupt
before returning from the interrupt handler. If the conditions that caused the interrupt are not
cleared, the interrupt request remains active.
12.5.3 Clearing an Interrupt Request
Clearing of the interrupt request is done by writing to registers in the corresponding peripheral
module, which then clears the corresponding NMIREQ/IREQ signal.
The recommended way of clearing an interrupt request is a store operation to the controlling
peripheral register, followed by a dummy load operation from the same register. This causes a
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pipeline stall, which prevents the interrupt from accidentally re-triggering in case the handler is
exited and the interrupt mask is cleared before the interrupt request is cleared.
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12.6 User Interface
Table 12-1. INTC Register Memory Map
Offset Register Register Name Access Reset
0x000 Interrupt Priority Register 0 IPR0 Read/Write 0x00000000
0x004 Interrupt Priority Register 1 IPR1 Read/Write 0x00000000
... ... ... ... ...
0x0FC Interrupt Priority Register 63 IPR63 Read/Write 0x00000000
0x100 Interrupt Request Register 0 IRR0 Read-only N/A
0x104 Interrupt Request Register 1 IRR1 Read-only N/A
... ... ... ... ...
0x1FC Interrupt Request Register 63 IRR63 Read-only N/A
0x200 Interrupt Cause Register 3 ICR3 Read-only N/A
0x204 Interrupt Cause Register 2 ICR2 Read-only N/A
0x208 Interrupt Cause Register 1 ICR1 Read-only N/A
0x20C Interrupt Cause Register 0 ICR0 Read-only N/A
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12.6.1 Interrupt Priority Registers
Name: IPR0...IPR63
Access Type: Read/Write
Offset: 0x000 - 0x0FC
Reset Value: 0x00000000
• INTLEVEL: Interrupt Level
Indicates the EVBA-relative offset of the interrupt handler of the corresponding group:
00: INT0: Lowest priority
01: INT1
10: INT2
11: INT3: Highest priority
• AUTOVECTOR: Autovector Address
Handler offset is used to give the address of the interrupt handler. The least significant bit should be written to zero to give
halfword alignment.
31 30 29 28 27 26 25 24
INTLEVEL - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - AUTOVECTOR[13:8]
76543210
AUTOVECTOR[7:0]
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12.6.2 Interrupt Request Registers
Name: IRR0...IRR63
Access Type: Read-only
Offset: 0x0FF - 0x1FC
Reset Value: N/A
• IRR: Interrupt Request line
This bit is cleared when no interrupt request is pending on this input request line.
This bit is set when an interrupt request is pending on this input request line.
The are 64 IRRs, one for each group. Each IRR has 32 bits, one for each possible interrupt request, for a total of 2048 possible
input lines. The IRRs are read by the software interrupt handler in order to determine which interrupt request is pending. The
IRRs are sampled continuously, and are read-only.
31 30 29 28 27 26 25 24
IRR[32*x+31] IRR[32*x+30] IRR[32*x+29] IRR[32*x+28] IRR[32*x+27] IRR[32*x+26] IRR[32*x+25] IRR[32*x+24]
23 22 21 20 19 18 17 16
IRR[32*x+23] IRR[32*x+22] IRR[32*x+21] IRR[32*x+20] IRR[32*x+19] IRR[32*x+18] IRR[32*x+17] IRR[32*x+16]
15 14 13 12 11 10 9 8
IRR[32*x+15] IRR[32*x+14] IRR[32*x+13] IRR[32*x+12] IRR[32*x+11] IRR[32*x+10] IRR[32*x+9] IRR[32*x+8]
76543210
IRR[32*x+7] IRR[32*x+6] IRR[32*x+5] IRR[32*x+4] IRR[32*x+3] IRR[32*x+2] IRR[32*x+1] IRR[32*x+0]
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12.6.3 Interrupt Cause Registers
Name: ICR0...ICR3
Access Type: Read-only
Offset: 0x200 - 0x20C
Reset Value: N/A
• CAUSE: Interrupt Group Causing Interrupt of Priority n
ICRn identifies the group with the highest priority that has a pending interrupt of level n. This value is only defined when at least
one interrupt of level n is pending.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CAUSE
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12.7 Module Configuration
The specific configuration for each INTC instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
12.7.1 Interrupt Request Signal Map
12.8 Interrupt Request Signal Map
The various modules may output Interrupt request signals. These signals are routed to the Interrupt
Controller (INTC), described in a later chapter. The Interrupt Controller supports up to 64
groups of interrupt requests. Each group can have up to 32 interrupt request signals. All interrupt
signals in the same group share the same autovector address and priority level. Refer to the
documentation for the individual submodules for a description of the semantics of the different
interrupt requests.
The interrupt request signals are connected to the INTC as follows.
Table 12-2. INTC Clock Name
Module Name Clock Name Description
INTC CLK_INTC Clock for the INTC bus interface
Table 12-3. Interrupt Request Signal Map
Group Line Module Signal
0 0 AVR32UC3 CPU SYSREG COMPARE
1
0 AVR32UC3 CPU OCD DCEMU_DIRTY
1 AVR32UC3 CPU OCD DCCPU_READ
2 0 Flash Controller FLASHCDW
3 0 Secure Access Unit SAU
4
0 Peripheral DMA Controller PDCA 0
1 Peripheral DMA Controller PDCA 1
2 Peripheral DMA Controller PDCA 2
3 Peripheral DMA Controller PDCA 3
5
0 Peripheral DMA Controller PDCA 4
1 Peripheral DMA Controller PDCA 5
2 Peripheral DMA Controller PDCA 6
3 Peripheral DMA Controller PDCA 7
6
0 Peripheral DMA Controller PDCA 8
1 Peripheral DMA Controller PDCA 9
2 Peripheral DMA Controller PDCA 10
3 Peripheral DMA Controller PDCA 11
7 0 Power Manager PM
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8 0 System Control Interface SCIF
9 0 Asynchronous Timer AST ALARM
10
0 Asynchronous Timer AST PER
1 Asynchronous Timer AST OVF
2 Asynchronous Timer AST READY
3 Asynchronous Timer AST CLKREADY
11
0 External Interrupt Controller EIC 1
1 External Interrupt Controller EIC 2
2 External Interrupt Controller EIC 3
3 External Interrupt Controller EIC 4
12 0 External Interrupt Controller EIC 5
13 0 Frequency Meter FREQM
14
0 General-Purpose Input/Output Controller GPIO 0
1 General-Purpose Input/Output Controller GPIO 1
2 General-Purpose Input/Output Controller GPIO 2
3 General-Purpose Input/Output Controller GPIO 3
4 General-Purpose Input/Output Controller GPIO 4
5 General-Purpose Input/Output Controller GPIO 5
6 General-Purpose Input/Output Controller GPIO 6
7 General-Purpose Input/Output Controller GPIO 7
15 0 Universal Synchronous Asynchronous
Receiver Transmitter USART0
16 0 Universal Synchronous Asynchronous
Receiver Transmitter USART1
17 0 Universal Synchronous Asynchronous
Receiver Transmitter USART2
18 0 Universal Synchronous Asynchronous
Receiver Transmitter USART3
19 0 Serial Peripheral Interface SPI
20 0 Two-wire Master Interface TWIM0
21 0 Two-wire Master Interface TWIM1
22 0 Two-wire Slave Interface TWIS0
23 0 Two-wire Slave Interface TWIS1
24 0 Pulse Width Modulation Controller PWMA
25
0 Timer/Counter TC00
1 Timer/Counter TC01
2 Timer/Counter TC02
Table 12-3. Interrupt Request Signal Map
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26
0 Timer/Counter TC10
1 Timer/Counter TC11
2 Timer/Counter TC12
27 0 ADC Interface ADCIFB
28 0 Analog Comparator Interface ACIFB
29 0 Capacitive Touch Module CAT
30 0 aWire AW
31 0 Audio Bitstream DAC ABDACB
32 0 USB 2.0 Interface USBC
33 0 Inter-IC Sound (I2S) Controller IISC
Table 12-3. Interrupt Request Signal Map
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13. Power Manager (PM)
Rev: 4.2.0.4
13.1 Features
• Generates clocks and resets for digital logic
• On-the-fly frequency change of CPU, HSB and PBx clocks
• Sleep modes allow simple disabling of logic clocks and clock sources
• Module-level clock gating through maskable peripheral clocks
• Wake-up from internal or external interrupts
• Automatic identification of reset sources
• Supports advanced Shutdown sleep mode
13.2 Overview
The Power Manager (PM) provides synchronous clocks used to clock the main digital logic in the
device, namely the CPU, and the modules and peripherals connected to the High Speed Bus
(HSB) and the Peripheral Buses (PBx).
The PM contains advanced power-saving features, allowing the user to optimize the power consumption
for an application. The synchronous clocks are divided into a number of clock
domains, one for the CPU and HSB, and one for each PBx. The clocks can run at different
speeds, allowing the user to save power by running peripherals relatively slow, whilst maintaining
high CPU performance. The clocks can be independently changed on-the-fly, without halting
any peripherals. The user may adjust CPU and memory speeds according to the dynamic application
load, without disturbing or re-configuring active peripherals.
Each module has a separate clock, enabling the user to save power by switching off clocks to
inactive modules. Clocks and oscillators can be automatically switched off during idle periods by
the CPU sleep instruction. The system will return to normal operation when interrupts occur.
To achieve minimal power usage, a special sleep mode, called Shutdown is available, where
power on all internal logic (CPU, peripherals) and most of the I/O lines is removed, reducing current
leakage. Only a small amount of logic, including the 32KHz crystal oscillator (OSC32K) and
the AST remain powered.
The Power Manager also contains a Reset Controller, which collects all possible reset sources,
generates hard and soft resets, and allows the reset source to be identified by software.
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13.3 Block Diagram
Figure 13-1. PM Block Diagram
13.4 I/O Lines Description
13.5 Product Dependencies
13.5.1 Interrupt
The PM interrupt line is connected to one of the interrupt controllers internal sources. Using the
PM interrupt requires the interrupt controller to be configured first.
13.5.2 Clock Implementation
In ATUC64/128/256L3/4U, the HSB shares source clock with the CPU. Write attempts to the
HSB Clock Select register (HSBSEL) will be ignored, and it will always read the same as the
CPU Clock Select register (CPUSEL).
The PM bus interface clock (CLK_PM) is generated by the Power Manager. This clock is
enabled at reset, and can be disabled in the Power Manager. If disabled it can only be reenabled
by a reset.
13.5.3 Power Considerations
The Shutdown mode is only available for the “3.3V supply mode, with 1.8V regulated I/O lines“
power configuration.
Table 13-1. I/O Lines Description
Name Description Type Active Level
RESET_N Reset Input Low
Sleep Controller
Synchronous
Clock Generator
Reset Controller
Main Clock Sources
Sleep
Instruction
Power-on Reset
Detector(s)
Resets
Synchronous
clocks
CPU, HSB,
PBx
Interrupts
External Reset Pin
Reset Sources
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13.6 Functional Description
13.6.1 Synchronous Clocks
The System RC Oscillator (RCSYS) and a selection of other clock sources can provide the
source for the main clock, which is the origin for the synchronous CPU/HSB and PBx module
clocks. For details about the other main clock sources, please refer to the Main Clock Control
(MCCTRL) register description. The synchronous clocks can run of the main clock and all the 8-
bit prescaler settings as long as fCPU fPBx,. The synchronous clock source can be changed onthe
fly, according to variations in application load. The clock domains can be shut down in sleep
mode, as described in Section 13.6.3. The module clocks in every synchronous clock domain
can be individually masked to minimize power consumption in inactive modules.
Figure 13-2. Synchronous Clock Generation
13.6.1.1 Selecting the main clock source
The common main clock can be connected to RCSYS or a selection of other clock sources. For
details about the other main clock sources, please refer to the MCCTRL register description. By
default, the main clock will be connected to RCSYS. The user can connect the main clock to
another source by writing to the Main Clock Select (MCCTRL.MCSEL) field. The user must first
assure that the source is enabled and ready in order to avoid a deadlock. Care should also be
taken so that the new synchronous clock frequencies do not exceed the maximum frequency for
each clock domain.
13.6.1.2 Selecting synchronous clock division ratio
The main clock feeds an 8-bit prescaler, which can be used to generate the synchronous clocks.
By default, the synchronous clocks run on the undivided main clock. The user can select a prescaler
division for the CPU clock by writing a one to the CPU Division bit in the CPU Clock Select
register (CPUSEL.CPUDIV), and a value to the CPU Clock Select field (CPUSEL.CPUSEL),
resulting in a CPU clock frequency:
fCPU = fmain / 2(CPUSEL+1)
Mask
Prescaler Main Clock
Sources
MCSEL
0
1
CPUSEL
CPUDIV
Main Clock
Sleep
Controller
CPUMASK
CPU Clocks
HSB Clocks
PBx Clocks
Sleep
Instruction
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Similarly, the PBx clocks can be divided by writing their respective Clock Select (PBxSEL) registers
to get the divided PBx frequency:
fPBx = fmain / 2(PBSEL+1)
The PBx clock frequency can not exceed the CPU clock frequency. The user must select a PBxSEL.PBSEL
value greater than or equal to the CPUSEL.CPUSEL value, so that fCPU fPBx. If the
user selects division factors that will result in fCPU< fPBx, the Power Manager will automatically
change the PBxSEL.PBSEL/PBDIV values to ensure correct operation (fCPU fPBx).
The HSB clock will always be forced to the same division as the CPU clock.
To ensure correct operation, the frequencies must never exceed the specified maximum frequency
for each clock domain.
For modules connected to the HSB bus, the PB clock frequency must be the same as the CPU
clock frequency.
13.6.1.3 Clock Ready flag
There is a slight delay from CPUSEL and PBxSEL being written to the new clock setting taking
effect. During this interval, the Clock Ready bit in the Status Register (SR.CKRDY) will read as
zero. When the clock settings change is completed, the bit will read as one. The Clock Select
registers (CPUSEL, PBxSEL) must not be written to while SR.CKRDY is zero, or the system
may become unstable or hang.
The Clock Ready bit in the Interrupt Status Register (ISR.CKRDY) is set on a SR.CKRDY zeroto-one
transition. If the Clock Ready bit in the Interrupt Mask Register (IMR.CKRDY) is set, an
interrupt request is generated. IMR.CKRDY is set by writing a one to the corresponding bit in the
Interrupt Enable Register (IER.CKRDY).
13.6.2 Peripheral Clock Masking
By default, the clocks for all modules are enabled, regardless of which modules are actually
being used. It is possible to disable the clock for a module in the CPU, HSB, or PBx clock
domain by writing a zero to the corresponding bit in the corresponding Clock Mask (CPUMASK/HSBMASK/PBxMASK)
register. When a module is not clocked, it will cease operation,
and its registers cannot be read nor written. The module can be re-enabled later by writing a one
to the corresponding mask bit. A module may be connected to several clock domains, in which
case it will have several mask bits. The Maskable Module Clocks table in the Clock Mask register
description contains a list of implemented maskable clocks.
13.6.2.1 Cautionary note
Note that clocks should only be switched off if it is certain that the module will not be used.
Switching off the clock for the Flash Controller will cause a problem if the CPU needs to read
from the flash. Switching off the clock to the Power Manager, which contains the mask registers,
or the corresponding PBx bridge, will make it impossible to write to the mask registers again. In
this case, they can only be re-enabled by a system reset.
13.6.3 Sleep Modes
In normal operation, all clock domains are active, allowing software execution and peripheral
operation. When the CPU is idle, it is possible to switch it and other (optional) clock domains off
to save power. This is done by the sleep instruction, which takes the sleep mode index number
from Table 13-2 on page 213 as argument.
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13.6.3.1 Entering and exiting sleep modes
The sleep instruction will halt the CPU and all modules belonging to the stopped clock domains.
The modules will be halted regardless of the bit settings in the mask registers.
Clock sources can also be switched off to save power. Some of these have a relatively long
start-up time, and are only switched off when very low power consumption is required.
The CPU and affected modules are restarted when the sleep mode is exited. This occurs when
an interrupt triggers. Note that even if an interrupt is enabled in sleep mode, it may not trigger if
the source module is not clocked.
13.6.3.2 Supported sleep modes
The following sleep modes are supported. These are detailed in Table 13-2 on page 213.
• Idle: The CPU is stopped, the rest of the device is operational.
• Frozen: The CPU and HSB modules are stopped, peripherals are operational.
• Standby: All synchronous clocks are stopped, and the clock sources are running, allowing for
a quick wake-up to normal mode.
• Stop: As Standby, but oscillators, and other clock sources are also stopped. 32KHz Oscillator
OSC32K(2), RCSYS, AST, and WDT will remain operational.
• DeepStop: All synchronous clocks and clock sources are stopped. Bandgap voltage
reference and BOD are turned off. OSC32K(2) and RCSYS remain operational.
• Static: All clock sources, including RCSYS are stopped. Bandgap voltage reference and BOD
are turned off. OSC32K(2) remains operational.
• Shutdown: All clock sources, including RCSYS are stopped. Bandgap voltage reference,
BOD detector, and Voltage regulator are turned off. OSC32K(2) remains operational. This
mode can only be used in the “3.3V supply mode, with 1.8V regulated I/O lines“
configuration (described in Power Considerations chapter). Refer to Section 13.6.4 for more
details.
Notes: 1. The sleep mode index is used as argument for the sleep instruction.
2. OSC32K will only remain operational if pre-enabled.
3. Clock sources other than those specifically listed in the table.
4. SYSTIMER is the clock for the CPU COUNT and COMPARE registers.
The internal voltage regulator is also adjusted according to the sleep mode in order to reduce its
power consumption.
Table 13-2. Sleep Modes
Index(1) Sleep Mode CPU HSB
PBx,
GCLK
Clock Sources(3),
SYSTIMER(4) OSC32K(2) RCSYS
BOD &
Bandgap
Voltage
Regulator
0 Idle Stop Run Run Run Run Run On Normal mode
1 Frozen Stop Stop Run Run Run Run On Normal mode
2 Standby Stop Stop Stop Run Run Run On Normal mode
3 Stop Stop Stop Stop Stop Run Run On Low power mode
4 DeepStop Stop Stop Stop Stop Run Run Off Low power mode
5 Static Stop Stop Stop Stop Run Stop Off Low power mode
6 Shutdown Stop Stop Stop Stop Run Stop Off Off
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13.6.3.3 Waking from sleep modes
There are two types of wake-up sources from sleep mode, synchronous and asynchronous.
Synchronous wake-up sources are all non-masked interrupts. Asynchronous wake-up sources
are AST, WDT, external interrupts from EIC, external reset, external wake pin (WAKE_N), and
all asynchronous wake-ups enabled in the Asynchronous Wake Up Enable (AWEN) register. The
valid wake-up sources for each sleep mode are detailed in Table 13-3 on page 214.
In Shutdown the only wake-up sources are external reset, external wake-up pin or AST. See
Section 13.6.4.3 on page 216.
Notes: 1. The sleep mode index is used as argument for the sleep instruction.
2. Only PB modules operational, as HSB module clocks are stopped.
3. WDT only available if clocked from pre-enabled OSC32K.
13.6.3.4 SleepWalking
In all sleep modes where the PBx clocks are stopped, except for Shutdown mode, the device
can partially wake up if a PBx module asynchronously discovers that it needs its clock. Only the
requested clocks and clock sources needed will be started, all other clocks will remain masked
to zero. E.g. if the main clock source is OSC0, only OSC0 will be started even if other clock
sources were enabled in normal mode. Generic clocks can also be started in a similar way. The
state where only requested clocks are running is referred to as SleepWalking.
The time spent to start the requested clock is mostly limited by the startup time of the given clock
source. This allows PBx modules to handle incoming requests, while still keeping the power consumption
at a minimum.
When the device is SleepWalking any asynchronous wake-up can wake the device up at any
time without stopping the requested PBx clock.
All requests to start clocks can be masked by writing to the Peripheral Power Control Register
(PPCR), all requests are enabled at reset.
During SleepWalking the interrupt controller clock will be running. If an interrupt is pending when
entering SleepWalking, it will wake the whole device up.
13.6.3.5 Precautions when entering sleep mode
Modules communicating with external circuits should normally be disabled before entering a
sleep mode that will stop the module operation. This will prevent erratic behavior caused by
entering or exiting sleep modes. Please refer to the relevant module documentation for recommended
actions.
Table 13-3. Wake-up Sources
Index(1) Sleep Mode Wake-up Sources
0 Idle Synchronous, Asynchronous
1 Frozen Synchronous(2), Asynchronous
2 Standby Asynchronous
3 Stop Asynchronous
4 DeepStop Asynchronous
5 Static Asynchronous(3)
6 Shutdown External reset, External wake-up pin
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Communication between the synchronous clock domains is disturbed when entering and exiting
sleep modes. Bus transactions over clock domains affected by the sleep mode are therefore not
recommended. The system may hang if the bus clocks are stopped during a bus transaction.
The CPU is automatically stopped in a safe state to ensure that all CPU bus operations are complete
when the sleep mode goes into effect. Thus, when entering Idle mode, no further action is
necessary.
When entering a sleep mode (except Idle mode), all HSB masters must be stopped before
entering the sleep mode. In order to let potential PBx write operations complete, the user should
let the CPU perform a PBx register read operation before issuing the sleep instruction. This will
stall the CPU until pending PBx operations have completed.
The Shutdown sleep mode requires extra care. Please refer to Section 13.6.4.
13.6.4 Shutdown Sleep Mode
13.6.4.1 Description
The Shutdown sleep mode is available only when the device is used in the “3.3V supply mode,
with 1.8V regulated I/O lines“ configuration (refer to the Power Considerations chapter). In this
configuration, the voltage regulator supplies both VDDCORE and VDDIO power supplies.
When the device enters Shutdown mode, the regulator is turned off and only the following logic
is kept powered by VDDIN:
– OSC32K using alternate pinout PA13/PA20
– AST core logic (internal counter and alarm detection logic)
– Backup Registers
– I/O lines PA11, PA13, PA20, PA21, PB04, PB05, and PB10
– RESET_N line
The table below lists I/O line functionality that remains operational during Shutdown sleep mode.
If no special function is used the I/O line will keep its setting when entering the sleep mode
13.6.4.2 Entering Shutdown sleep mode
Before entering the Shutdown sleep mode, a few actions are required:
– All modules should normally be disabled before entering Shutdown sleep mode (see
Section 13.6.3.5)
Table 13-4. I/O Lines Usage During Shutdown Mode
Pin Possible Usage During Shutdown Sleep Mode
PA11 WAKE_N signal (active low wake-up)
PA13 XIN32_2 (OSC32K using alternate pinout)
PA20 XOUT32_2 (OSC32K using alternate pinout)
PA21
PB04
PB05
PB10
RESET_N Reset pin
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– The POR33 must be masked to avoid spurious resets when the power is back. This
must also be done when POR33 is disabled, as POR33 will be enabled
automatically when the device wakes up from Shutdown mode. Disable the POR33
by writing a one to the POR33MASK bit in the SCIF.VREGCR register. Due to
internal synchronisation, this bit must be read as a one before the sleep instruction is
executed by the CPU. Refer to the System Control Interface (SCIF) chapter for more
details.
– The 32KHz RC oscillator (RC32K) must be running and stable. This is done by
writing a one to the EN bit in the SCIF.RC32KCR register. Due to internal
synchronisation, this bit must be read as a one to ensure that the oscillator is stable
before the sleep instruction is executed by the CPU.
As soon as the Shutdown sleep mode is entered, all CPU and peripherals are reset to ensure a
consistent state. POR33 and RC32K are automatically disabled to save extra power.
13.6.4.3 Leaving Shutdown sleep mode
Exiting Shutdown sleep mode can be done by the events described in Table 13-5.
When a wake-up event occurs, the regulator is turned on and the device will wait for VDDCORE
to be valid before starting. The Sleep Reset bit in the Reset Cause register (RCAUSE.SLEEP) is
then set, allowing software running on the device to distinguish between the first power-up and a
wake-up from Shutdown mode.
13.6.4.4 Special consideration regarding waking up from Shutdown sleep mode using the WAKE_N pin
By default, the WAKE_N pin will only wake the device up if it is pulled low after entering Shutdown
mode. If the WAKE_N is pulled low before the Shutdown mode is entered, it will not wake
the device from the Shutdown sleep mode. In order to wake the device by pulling WAKE_N low
before entering Shutdown mode, the user has to write a one to the bit corresponding to the
WAKEN wake-up source in the AWEN register. In this scenario, the CPU execution will proceed
with the next instruction, and the RCAUSE register content will not be altered.
13.6.5 Divided PB Clocks
The clock generator in the Power Manager provides divided PBx clocks for use by peripherals
that require a prescaled PBx clock. This is described in the documentation for the relevant modules.
The divided clocks are directly maskable, and are stopped in sleep modes where the PBx
clocks are stopped.
Table 13-5. Events That Can Wake up the Device from Shutdown Mode
Source How
PA11 (WAKE_N) Pulling-down PA11 will wake up the device
RESET_N
Pulling-down RESET_N pin will wake up the device
The device is kept under reset until RESET_N is tied high
again
AST
OSC32K must be set-up to use alternate pinout (XIN32_2
and XOUT32_2) Refer to the SCIF Chapter
AST must be configured to use the clock from OSC32K
AST must be configured to allow alarm, periodic, or
overflow wake-up
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13.6.6 Reset Controller
The Reset Controller collects the various reset sources in the system and generates hard and
soft resets for the digital logic.
The device contains a Power-on Reset (POR) detector, which keeps the system reset until
power is stable. This eliminates the need for external reset circuitry to guarantee stable operation
when powering up the device.
It is also possible to reset the device by pulling the RESET_N pin low. This pin has an internal
pull-up, and does not need to be driven externally during normal operation. Table 13-6 on page
217 lists these and other reset sources supported by the Reset Controller.
Figure 13-3. Reset Controller Block Diagram
In addition to the listed reset types, the JTAG & aWire can keep parts of the device statically
reset. See JTAG and aWire documentation for details.
Table 13-6. Reset Description
Reset Source Description
Power-on Reset Supply voltage below the Power-on Reset detector threshold
voltage VPOT
External Reset RESET_N pin asserted
Brown-out Reset VDDCORE supply voltage below the Brown-out detector
threshold voltage
JTAG
Reset
Controller
RESET_N
Power-on Reset
Detector(s)
OCD
Watchdog Reset
RCAUSE
CPU, HSB, PBx
OCD, AST, WDT,
Clock Generator
Brown-out
Detector
AWIRE
SM33 Detector
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Depending on the reset source, when a reset occurs, some parts of the device are not always
reset. Only the Power-on Reset (POR) will force a whole device reset. Refer to the table in the
Module Configuration section at the end of this chapter for further details. The latest reset cause
can be read in the RCAUSE register, and can be read during the applications boot sequence in
order to determine proper action.
13.6.6.1 Power-on Reset Detector
The Power-on Reset 1.8V (POR18) detector monitors the VDDCORE supply pin and generates
a Power-on Reset (POR) when the device is powered on. The POR is active until the
VDDCORE voltage is above the power-on threshold level (VPOT). The POR will be re-generated
if the voltage drops below the power-on threshold level. See Electrical Characteristics for parametric
details.
The Power-on Reset 3.3V (POR33) detector monitors the internal regulator supply pin and generates
a Power-on Reset (POR) when the device is powered on. The POR is active until the
internal regulator supply voltage is above the regulator power-on threshold level (VPOT). The
POR will be re-generated if the voltage drops below the regulator power-on threshold level. See
Electrical Characteristics for parametric details.
13.6.6.2 External Reset
The external reset detector monitors the RESET_N pin state. By default, a low level on this pin
will generate a reset.
13.6.7 Clock Failure Detector
This mechanism automatically switches the main clock source to the safe RCSYS clock when
the main clock source fails. This may happen when an external crystal is selected as a source
for the main clock and the crystal is not mounted on the board. The main clock is compared with
RCSYS, and if no rising edge of the main clock is detected during one RCSYS period, the clock
is considered to have failed.
The detector is enabled by writing a one to the Clock Failure Detection Enable bit in the Clock
Failure Detector Control Register (CFDCTRL.CFDEN). As soon as the detector is enabled, the
clock failure detector will monitor the divided main clock. Note that the detector does not monitor
the main clock if RCSYS is the source of the main clock, or if the main clock is temporarily not
available (startup-time after a wake-up, switching timing etc.), or in sleep mode where the main
clock is driven by the RCSYS (Stop and DeepStop mode). When a clock failure is detected, the
main clock automatically switches to the RCSYS clock and the Clock Failure Detected (CFD)
interrupt is generated if enabled. The MCCTRL register is also changed by hardware to indicate
that the main clock comes from RCSYS.
13.6.8 Interrupts
The PM has a number of interrupt sources:
• AE - Access Error,
SM33 Reset Internal regulator supply voltage below the SM33 threshold
voltage. This generates a Power-on Reset.
Watchdog Timer See Watchdog Timer documentation
OCD See On-Chip Debug documentation
Reset Source Description
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– A lock protected register is written to without first being unlocked.
• CKRDY - Clock Ready:
– New Clock Select settings in the CPUSEL/PBxSEL registers have taken effect. (A
zero-to-one transition on SR.CKRDY is detected).
• CFD - Clock Failure Detected:
– The system detects that the main clock is not running.
The Interrupt Status Register contains one bit for each interrupt source. A bit in this register is
set on a zero-to-one transition of the corresponding bit in the Status Register (SR), and cleared
by writing a one to the corresponding bit in the Interrupt Clear Register (ICR). The interrupt
sources will generate an interrupt request if the corresponding bit in the Interrupt Mask Register
is set. The interrupt sources are ORed together to form one interrupt request. The Power Manager
will generate an interrupt request if at least one of the bits in the Interrupt Mask Register
(IMR) is set. Bits in IMR are set by writing a one to the corresponding bit in the Interrupt Enable
Register (IER), and cleared by writing a one to the corresponding bit in the Interrupt Disable
Register (IDR). The interrupt request remains active until the corresponding bit in the Interrupt
Status Register (ISR) is cleared by writing a one to the corresponding bit in the Interrupt Clear
Register (ICR). Because all the interrupt sources are ORed together, the interrupt request from
the Power Manager will remain active until all the bits in ISR are cleared.
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13.7 User Interface
Note: 1. The reset value is device specific. Please refer to the Module Configuration section at the end of this chapter.
2. Latest Reset Source.
3. Latest Wake Source.
Table 13-7. PM Register Memory Map
Offset Register Register Name Access Reset
0x000 Main Clock Control MCCTRL Read/Write 0x00000000
0x004 CPU Clock Select CPUSEL Read/Write 0x00000000
0x008 HSB Clock Select HSBSEL Read-only 0x00000000
0x00C PBA Clock Select PBASEL Read/Write 0x00000000
0x010 PBB Clock Select PBBSEL Read/Write 0x00000000
0x014 - 0x01C Reserved
0x020 CPU Mask CPUMASK Read/Write 0x00010001
0x024 HSB Mask HSBMASK Read/Write 0x0000007F
0x028 PBA Mask PBAMASK Read/Write 0x0FFFFFFF
0x02C PBB Mask PBBMASK Read/Write 0x0000000F
0x030- 0x03C Reserved
0x040 PBA Divided Mask PBADIVMASK Read/Write 0x0000007F
0x044 - 0x050 Reserved
0x054 Clock Failure Detector Control CFDCTRL Read/Write 0x00000000
0x058 Unlock Register UNLOCK Write-only 0x00000000
0x05C - 0x0BC Reserved
0x0C0 Interrupt Enable Register IER Write-only 0x00000000
0x0C4 Interrupt Disable Register IDR Write-only 0x00000000
0x0C8 Interrupt Mask Register IMR Read-only 0x00000000
0x0CC Interrupt Status Register ISR Read-only 0x00000000
0x0D0 Interrupt Clear Register ICR Write-only 0x00000000
0x0D4 Status Register SR Read-only 0x00000020
0x0D8 - 0x15C Reserved
0x160 Peripheral Power Control Register PPCR Read/Write 0x000001FA
0x164 - 0x17C Reserved
0x180 Reset Cause Register RCAUSE Read-only -(2)
0x184 Wake Cause Register WCAUSE Read-only -(3)
0x188 Asynchronous Wake Up Enable Register AWEN Read/Write 0x00000000
0x18C - 0x3F4 Reserved
0x3F8 Configuration Register CONFIG Read-only 0x00000043
0x3FC Version Register VERSION Read-only -(1)
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13.7.1 Main Clock Control
Name: MCCTRL
Access Type: Read/Write
Offset: 0x000
Reset Value: 0x00000000
• MCSEL: Main Clock Select
Note: 1. If the 120MHz RC oscillator is selected as main clock source, it must be divided by at least 4 before being used as clock
source for the CPU. This division is selected by writing to the CPUSEL and CPUDIV bits in the CPUSEL register, before
switching to RC120M as main clock source.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - MCSEL
Table 13-8. Main clocks in ATUC64/128/256L3/4U.
MCSEL[2:0] Main clock source
0 System RC oscillator (RCSYS)
1 Oscillator0 (OSC0)
2 DFLL
3 120MHz RC oscillator
(RC120M)(1)
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13.7.2 CPU Clock Select
Name: CPUSEL
Access Type: Read/Write
Offset: 0x004
Reset Value: 0x00000000
• CPUDIV, CPUSEL: CPU Division and Clock Select
CPUDIV = 0: CPU clock equals main clock.
CPUDIV = 1: CPU clock equals main clock divided by 2(CPUSEL+1).
Note that if CPUDIV is written to 0, CPUSEL should also be written to 0 to ensure correct operation.
Also note that writing this register clears POSCSR.CKRDY. The register must not be re-written until CKRDY goes high.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
CPUDIV - - - - CPUSEL
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13.7.3 HSB Clock Select
Name: HSBSEL
Access Type: Read
Offset: 0x008
Reset Value: 0x00000000
This register is read-only and its content is always equal to CPUSEL.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
HSBDIV - - - - HSBSEL
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13.7.4 PBx Clock Select
Name: PBxSEL
Access Type: Read/Write
Offset: 0x00C-0x010
Reset Value: 0x00000000
• PBDIV, PBSEL: PBx Division and Clock Select
PBDIV = 0: PBx clock equals main clock.
PBDIV = 1: PBx clock equals main clock divided by 2(PBSEL+1).
Note that if PBDIV is written to 0, PBSEL should also be written to 0 to ensure correct operation.
Also note that writing this register clears SR.CKRDY. The register must not be re-written until SR.CKRDY is set.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
PBDIV - - - - PBSEL
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13.7.5 Clock Mask
Name: CPUMASK/HSBMASK/PBAMASK/PBBMASK
Access Type: Read/Write
Offset: 0x020-0x02C
Reset Value: -
• MASK: Clock Mask
If bit n is cleared, the clock for module n is stopped. If bit n is set, the clock for module n is enabled according to the current
power mode. The number of implemented bits in each mask register, as well as which module clock is controlled by each bit, is
shown in Table 13-9.
31 30 29 28 27 26 25 24
MASK[31:24]
23 22 21 20 19 18 17 16
MASK[23:16]
15 14 13 12 11 10 9 8
MASK[15:8]
76543210
MASK[7:0]
Table 13-9. Maskable Module Clocks in ATUC64/128/256L3/4U.
Bit CPUMASK HSBMASK PBAMASK PBBMASK
0 OCD PDCA PDCA FLASHCDW
1 - FLASHCDW INTC HMATRIX
2 - SAU PM SAU
3 - PBB bridge SCIF USBC
4 - PBA bridge AST -
5 - Peripheral Event System WDT -
6 - USBC EIC -
7 - - FREQM -
8 - - GPIO -
9 - - USART0 -
10 - - USART1 -
11 - - USART2 -
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Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
12 - - USART3 -
13 - - SPI -
14 - - TWIM0 -
15 - - TWIM1 -
16 SYSTIMER - TWIS0 -
17 - - TWIS1 -
18 - - PWMA -
19 - - TC0 -
20 - - TC1 -
21 - - ADCIFB -
22 - - ACIFB -
23 - - CAT -
24 - - GLOC -
25 - - AW -
26 - - ABDACB -
27 - - IISC -
31:28 - - - -
Table 13-9. Maskable Module Clocks in ATUC64/128/256L3/4U.
Bit CPUMASK HSBMASK PBAMASK PBBMASK
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13.7.6 PBA Divided Mask
Name: PBADIVMASK
Access Type: Read/Write
Offset: 0x040
Reset Value: 0x0000007F
• MASK: Clock Mask
If bit n is written to zero, the clock divided by 2(n+1) is stopped. If bit n is written to one, the clock divided by 2(n+1) is enabled
according to the current power mode. Table 13-10 shows what clocks are affected by the different MASK bits.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- ------
15 14 13 12 11 10 9 8
--------
76543210
- MASK[6:0]
Table 13-10. Divided Clock Mask
Bit USART0 USART1 USART2 USART3 TC0 TC1
0 - - - - TIMER_CLOCK2 TIMER_CLOCK2
1- - - - - -
2 CLK_USART/
DIV
CLK_USART/
DIV
CLK_USART/
DIV
CLK_USART/
DIV TIMER_CLOCK3 TIMER_CLOCK3
3- - - - - -
4 - - - - TIMER_CLOCK4 TIMER_CLOCK4
5- - - - - -
6 - - - - TIMER_CLOCK5 TIMER_CLOCK5
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13.7.7 Clock Failure Detector Control Register
Name: CFDCTRL
Access Type: Read/Write
Offset: 0x054
Reset Value: 0x00000000
• SFV: Store Final Value
0: The register is read/write
1: The register is read-only, to protect against further accidental writes.
• CFDEN: Clock Failure Detection Enable
0: Clock Failure Detector is disabled
1: Clock Failure Detector is enabled
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
SFV - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - CFDEN
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13.7.8 Unlock Register
Name: UNLOCK
Access Type: Write-only
Offset: 0x058
Reset Value: 0x00000000
To unlock a write protected register, first write to the UNLOCK register with the address of the register to unlock in the
ADDR field and 0xAA in the KEY field. Then, in the next PB access write to the register specified in the ADDR field.
• KEY: Unlock Key
Write this bit field to 0xAA to enable unlock.
• ADDR: Unlock Address
Write the address of the register to unlock to this field.
31 30 29 28 27 26 25 24
KEY
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - ADDR[9:8]
76543210
ADDR[7:0]
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13.7.9 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x0C0
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.10 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x0C4
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.11 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x0C8
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.12 Interrupt Status Register
Name: ISR
Access Type: Read-only
Offset: 0x0CC
Reset Value: 0x00000000
0: The corresponding interrupt is cleared.
1: The corresponding interrupt is pending.
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set on a zero-to-one transition of the corresponding bit in the Status Register (SR).
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.13 Interrupt Clear Register
Name: ICR
Access Type: Write-only
Offset: 0x0D0
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in ISR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.14 Status Register
Name: SR
Access Type: Read-only
Offset: 0x0D4
Reset Value: 0x00000020
• AE: Access Error
0: No access error has occurred.
1: A write to lock protected register without unlocking it has occurred.
• CKRDY: Clock Ready
0: One of the CPUSEL/PBxSEL registers has been written, and the new clock setting is not yet effective.
1: The synchronous clocks have frequencies as indicated in the CPUSEL/PBxSEL registers.
• CFD: Clock Failure Detected
0: Main clock is running correctly.
1: Failure on main clock detected. Main clock is now running on RCSYS.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - CKRDY - - - - CFD
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13.7.15 Peripheral Power Control Register
Name: PPCR
Access Type: Read/Write
Offset: 0x004
Reset Value: 0x000001FA
• RSTTM: Reset test mode
0: External reset not in test mode
1: External reset in test mode
• FRC32: Force RC32 out
0: RC32 signal is not forced as output
1: RC32 signal is forced as output
• RSTPUN: Reset Pull-up, active low
0: Pull-up for external reset on
1: Pull-up for external reset off
31 30 29 28 27 26 25 24
PPC[31:24]
23 22 21 20 19 18 17 16
PPC[23:16]
15 14 13 12 11 10 9 8
PPC[15:8]
76543210
PPC[7:0]
Table 13-11. Peripheral Power Control
Bit Name
0 RSTPUN
1 FRC32
2 RSTTM
3 CATRCMASK
4 ACIFBCRCMASK
5 ADCIFBRCMASK
6 ASTRCMASK
7 TWIS0RCMASK
8 TWIS1RCMASK
31:9 -
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• CATRCMASK: CAT Request Clock Mask
0: CAT Request Clock is disabled
1: CAT Request Clock is enabled
• ACIFBRCMASK: ACIFB Request Clock Mask
0: ACIFB Request Clock is disabled
1: ACIFB Request Clock is enabled
• ADCIFBRCMASK: ADCIFB Request Clock Mask
0: ADCIFB Request Clock is disabled
1: ADCIFB Request Clock is enabled
• ASTRCMASK: AST Request Clock Mask
0: AST Request Clock is disabled
1: AST Request Clock is enabled
• TWIS0RCMASK: TWIS0 Request Clock Mask
0: TWIS0 Request Clock is disabled
1: TWIS0 Request Clock is enabled
• TWIS1RCMASK: TWIS1 Request Clock Mask
0: TWIS1 Request Clock is disabled
1: TWIS1 Request Clock is enabled
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
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13.7.16 Reset Cause Register
Name: RCAUSE
Access Type: Read-only
Offset: 0x180
Reset Value: Latest Reset Source
• AWIRE: aWire Reset
This bit is set when the last reset was caused by the aWire.
• JTAG: JTAG Reset
This bit is set when the last reset was caused by the JTAG.
• OCDRST: OCD Reset
This bit is set when the last reset was due to the RES bit in the OCD Development Control register having been written to one.
• SLEEP: Sleep Reset
This bit is set when the last reset was due to the device waking up from the Shutdown sleep mode.
• WDT: Watchdog Reset
This bit is set when the last reset was due to a watchdog time-out.
• EXT: External Reset Pin
This bit is set when the last reset was due to the RESET_N pin being pulled low.
• BOD: Brown-out Reset
This bit is set when the last reset was due to the core supply voltage being lower than the brown-out threshold level.
• POR: Power-on Reset
This bit is set when the last reset was due to the core supply voltage VDDCORE being lower than the power-on threshold level
(the reset is generated by the POR18 detector), or the internal regulator supply voltage being lower than the regulator power-on
threshold level (generated by the POR33 detector), or the internal regulator supply voltage being lower than the minimum
required input voltage (generated by the 3.3V supply monitor SM33).
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - AWIRE - JTAG OCDRST
76543210
- SLEEP - - WDT EXT BOD POR
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13.7.17 Wake Cause Register
Name: WCAUSE
Access Type: Read-only
Offset: 0x184
Reset Value: Latest Wake Source
A bit in this register is set on wake up caused by the peripheral referred to in Table 13-12 on page 239.
31 30 29 28 27 26 25 24
WCAUSE[31:24]
23 22 21 20 19 18 17 16
WCAUSE[23:16]
15 14 13 12 11 10 9 8
WCAUSE[15:8]
76543210
WCAUSE[7:0]
Table 13-12. Wake Cause
Bit Wake Cause
0 CAT
1 ACIFB
2 ADCIFB
3 TWI Slave 0
4 TWI Slave 1
5 WAKE_N
6 ADCIFB Pen Detect
7 USBC
15:8 -
16 EIC
17 AST
31:18 -
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13.7.18 Asynchronous Wake Up Enable Register
Name: AWEN
Access Type: Read/Write
Offset: 0x188
Reset Value: 0x00000000
Each bit in this register corresponds to an asynchronous wake-up source, according to Table 13-13 on page 240.
0: The corresponding wake up is disabled.
1: The corresponding wake up is enabled
31 30 29 28 27 26 25 24
AWEN[31:24]
23 22 21 20 19 18 17 16
AWEN[23:16]
15 14 13 12 11 10 9 8
AWEN[15:8]
76543210
AWEN[7:0]
Table 13-13. Asynchronous Wake-up Sources
Bit Asynchronous Wake-up Source
0 CAT
1 ACIFB
2 ADCIFB
3 TWIS0
4 TWIS1
5 WAKEN
6 ADCIFBPD
7 USBC
31:8 -
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13.7.19 Configuration Register
Name: CONFIG
Access Type: Read-Only
Offset: 0x3F8
Reset Value: -
This register shows the configuration of the PM.
• HSBPEVC:HSB PEVC Clock Implemented
0: HSBPEVC not implemented.
1: HSBPEVC implemented.
• PBD: PBD Implemented
0: PBD not implemented.
1: PBD implemented.
• PBC: PBC Implemented
0: PBC not implemented.
1: PBC implemented.
• PBB: PBB Implemented
0: PBB not implemented.
1: PBB implemented.
• PBA: PBA Implemented
0: PBA not implemented.
1: PBA implemented.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
HSBPEVC - - - PBD PBC PBB PBA
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13.7.20 Version Register
Name: VERSION
Access Type: Read-Only
Offset: 0x3FC
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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13.8 Module Configuration
The specific configuration for each PM instance is listed in the following tables. The module bus
clocks listed here are connected to the system bus clocks. Please refer to the “Synchronous
Clocks”, “Peripheral Clock Masking” and “Sleep Modes” sections for details.
Table 13-14. Power Manager Clocks
Clock Name Description
CLK_PM Clock for the PM bus interface
Table 13-15. Register Reset Values
Register Reset Value
VERSION 0x00000420
Table 13-16. Effect of the Different Reset Events
Power-on
Reset
External
Reset
Watchdog
Reset
BOD
Reset
SM33
Reset
CPU Error
Reset
OCD
Reset
JTAG
Reset
CPU/HSB/PBx
(excluding Power Manager)
Y Y Y YY Y YY
32KHz oscillator Y N N N N N N N
RC Oscillator Calibration register Y N N N N N N N
Other oscillator control registers Y Y Y Y Y Y Y Y
AST registers, except interrupt
registers
Y N N NN N NN
Watchdog control register Y Y N Y Y Y Y Y
Voltage Calibration register Y N N N N N N N
SM33 control register Y Y Y Y Y Y Y Y
BOD control register Y Y Y N Y Y Y Y
Clock control registers Y Y Y Y Y Y Y Y
OCD system and OCD registers Y Y N Y Y Y N Y
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14. System Control Interface (SCIF)
Rev: 1.1.0.0
14.1 Features
• Supports crystal oscillator 0.45-16MHz (OSC0)
• Supports Digital Frequency Locked Loop 20-150MHz (DFLL)
• Supports Phase Locked Loop 80-240MHz (PLL)
• Supports 32KHz ultra-low-power oscillator (OSC32K)
• Supports 32kHz RC oscillator (RC32K)
• Integrated low-power RC oscillator (RCSYS)
• Generic clocks (GCLK) with wide frequency range provided
• Generic Clock Prescaler
• Controls Bandgap
• Controls Brown-out detectors (BOD) and supply monitors
• Controls Voltage Regulator (VREG) behavior and calibration
• Controls Temperature Sensor
• Controls Supply Monitor 33 (SM33) operating modes and calibration
• Controls 120MHz integrated RC Oscillator (RC120M)
• Four 32-bit general-purpose backup registers
14.2 Overview
The System Control Interface (SCIF) controls the oscillators, Generic Clocks, BODs, Bandgap,
VREG, Temperature Sensor, and Backup Registers.
14.3 I/O Lines Description
14.4 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
Table 14-1. I/O Lines Description
Pin Name Pin Description Type
RC32OUT RC32 output at startup Output
XIN0 Crystal 0 Input Analog/Digital
XIN32 Crystal 32 Input (primary location) Analog/Digital
XIN32_2 Crystal 32 Input (secondary location) Analog/Digital
XOUT0 Crystal 0 Output Analog
XOUT32 Crystal 32 Output (primary location) Analog
XOUT32_2 Crystal 32 Output (secondary location) Analog
GCLK9-GCLK0 Generic Clock Output Output
GCLK_IN2-GCLK_IN0 Generic Clock Input Input
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14.4.1 I/O Lines
The SCIF provides a number of generic clock outputs, which can be connected to output pins,
multiplexed with GPIO lines. The programmer must first program the GPIO controller to assign
these pins to their peripheral function. If the I/O pins of the SCIF are not used by the application,
they can be used for other purposes by the GPIO controller. Oscillator pins are also multiplexed
with GPIO. When oscillators are used, the related pins are controlled directly by the SCIF, overriding
GPIO settings.
RC32OUT will be output after reset, and the GPIO controller can assign this pin to other peripheral
function after start-up.
14.4.2 Power Management
The BODs and all the oscillators, except the 32KHz oscillator (OSC32K) are turned off in some
sleep modes and turned automatically on when the device wakes up. The Voltage Regulator is
set in low power mode in some sleep modes and automatically set back in normal mode when
the device wakes up. Please refer to the Power Manager chapter for details.
The BOD control registers will not be reset by the Power Manager on a BOD reset.
14.4.3 Clocks
The SCIF controls all oscillators in the device. The oscillators can be used as source for the CPU
and peripherals. Selection of source is done in the Power Manager. The oscillators can also be
used as source for generic clocks.
14.4.4 Interrupts
The SCIF interrupt request line is connected to the interrupt controller. Using the SCIF interrupt
requires the interrupt controller to be programmed first.
14.4.5 Debug Operation
The SCIF does not interact with debug operations.
14.5 Functional Description
14.5.1 Oscillator (OSC) Operation
Rev: 1.1.1.0
The main oscillator (OSCn) is designed to be used with an external 0.450 to 16MHz crystal and
two biasing capacitors, as shown in the Electrical Characteristics chapter, or with an external
clock connected to the XIN. The oscillator can be used as source for the main clock in the
device, as described in the Power Manager chapter. The oscillator can be used as source for the
generic clocks, as described in the Generic Clocks section.
The oscillator is disabled by default after reset. When the oscillator is disabled, the XIN and
XOUT pins can be used as general purpose I/Os. When the oscillator is enabled, the XIN and
XOUT pins are controlled directly by the SCIF, overriding GPIO settings. When the oscillator is
configured to use an external clock, the clock must be applied to the XIN pin while the XOUT pin
can be used as general purpose I/O.
The oscillator is enabled by writing a one to the Oscillator Enable bit in the Oscillator Control register
(OSCCTRLn.OSCEN). Operation mode (external clock or crystal) is selected by writing to
the Oscillator Mode bit in OSCCTRLn (OSCCTRLn.MODE). The oscillator is automatically dis-
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abled in certain sleep modes to reduce power consumption, as described in the Power Manager
chapter.
After a hard reset, or when waking up from a sleep mode where the oscillators were disabled,
the oscillator will need a certain amount of time to stabilize on the correct frequency. This startup
time can be set in the OSCCTRLn register.
The SCIF masks the oscillator outputs during the start-up time, to ensure that no unstable clocks
propagate to the digital logic.
The OSCn Ready bit in the Power and Clock Status Register (PCLKSR.OSCnRDY) is set when
the oscillator is stable and ready to be used as clock source. An interrupt can be generated on a
zero-to-one transition on OSCnRDY if the OSCnRDY bit in the Interrupt Mask Register
(IMR.OSCnRDY) is set. This bit is set by writing a one to the corresponding bit in the Interrupt
Enable Register (IER.OSCnRDY).
14.5.2 32KHz Oscillator (OSC32K) Operation
Rev: 1.1.0.1
The 32KHz oscillator operates as described for the oscillator above. The 32KHz oscillator can
be used as source clock for the Asynchronous Timer (AST) and the Watchdog Timer (WDT).
The 32KHz oscillator can also be used as source for the generic clocks.
The oscillator is disabled by default after reset. When the oscillator is disabled, the XIN32 and
XOUT32 pins can be used as general-purpose I/Os. When the oscillator is enabled, the XIN32
and XOUT32 pins are controlled directly by the SCIF, overriding GPIO settings. When the oscillator
is configured to use an external clock, the clock must be applied to the XIN32 pin while the
XOUT32 pin can be used as general-purpose I/O.
The oscillator is enabled writing a one to the OSC32 Enable bit in the 32KHz Oscillator Control
Register (OSCCTRL32OSC32EN). The oscillator is disabled by writing a zero to the OSC32EN
bit, while keeping the other bits unchanged. Writing to OSC32EN while also writing to other bits
may result in unpredictable behavior. Operation mode (external clock or crystal) is selected by
writing to the Oscillator Mode bit in OSCCTRL32 (OSCCTRL32.MODE). The oscillator is an
ultra-low-power design and remains enabled in all sleep modes.
The start-up time of the 32KHz oscillator is selected by writing to the Oscillator Start-up Time
field in the OSCCTRL32 register (OSCCTRL32.STARTUP). The SCIF masks the oscillator output
during the start-up time, to ensure that no unstable clock cycles propagate to the digital logic.
The OSC32 Ready bit in the Power and Clock Status Register (PCLKSR.OSC32RDY) is set
when the oscillator is stable and ready to be used as clock source. An interrupt can be generated
on a zero-to-one transition on PCLKSR.OSC32RDY if the OSC32RDY bit in the Interrupt
Mask Register (IMR.OSC32RDY) is set. This bit is set by writing a one to the corresponding bit
in the Interrupt Enable Register (IER.OSC32RDY).
.As a crystal oscillator usually requires a very long start-up time (up to 1 second), the 32KHz
oscillator will keep running across resets, except a Power-on Reset (POR).
The 32KHz oscillator also has a 1KHz output. This is enabled by writing a one to the Enable
1KHz output bit in OSCCTRL32 register (OSCCTRL32.EN1K). If the 32KHz output clock is not
needed when 1K is enabled, this can be disabled by writing a zero to the Enable 32KHz output
bit in the OSCCTRL32 register (OSCCTRL32.EN32K). OSCCTRL32.EN32K is set after a POR.
The 32KHz oscillator has two possible sets of pins. To select between them write to the Pin
Select bit in the OSCCTRL32 register (OSCCTRL32.PINSEL). If the 32KHz oscillator is to be
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used in Shutdown mode, PINSEL must be written to one, and XIN32_2 and XOUT32_2 must be
used.
14.5.3 PLL Operation
Rev: 1.1.0.0
The device contains one Phase Locked Loop (PLL), which is controlled by the Phase Locked
Loop Interface (PLLIF). The PLL is disabled by default, but can be enabled to provide high frequency
source clocks for synchronous or generic clocks. The PLL can use different clock
sources as reference clock, please refer to the “PLL Clock Sources” table in the SCIF Module
Configuration section for details. The PLL output is divided by a multiplication factor, and the
PLL compares the phase of the resulting clock to the reference clock. The PLL will adjust its output
frequency until the two compared clocks phases are equal, thus locking the output frequency
to a multiple of the reference clock frequency.
When the PLL is switched on, or when changing the clock source or multiplication factor for the
PLL, the PLL is unlocked and the output frequency is undefined. The PLL clock for the digital
logic is automatically masked when the PLL is unlocked, to prevent the connected digital logic
from receiving a too high frequency and thus become unstable.
The PLL can be configured by writing the PLL Control Register (PLLn). To prevent unexpected
writes due to software bugs, write access to the PLLn register is protected by a locking mechanism,
for details please refer to the UNLOCK register description.
Figure 14-1. PLL with Control Logic and Filters
14.5.3.1 Enabling the PLL
Before the PLL is enabled it must be set up correctly. The PLL Oscillator Select field (PLLOSC)
selects a source for the reference clock. The PLL Multiply Factor (PLLMUL) and PLL Division
Phase
Detector
Output
Divider
Source
clocks
PLLOSC PLLOPT[0]
PLLMUL
Lock bit
Mask PLL clock
Input
Divider
PLLDIV
1/2
PLLOPT[1]
0
1
VCO
fvco fPLL
Lock
Counter
fREF
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Factor (PLLDIV) fields must be written with the multiplication and division factors, respectively.
The PLLMUL must always be greater than 1, creating the PLL frequency:
fvco = (PLLMUL+1)/PLLDIV • fREF, if PLLDIV >0
fvco = 2•(PLLMUL+1) • fREF, if PLLDIV = 0
The PLL Options (PLLOPT) field should be configured to proper values according to the PLL
operating frequency. The PLLOPT field can also be configured to divide the output frequency of
the PLL by 2 and Wide-Bandwidth mode, which allows faster startup time and out-of-lock time.
It is not possible to change any of the PLL configuration bits when the PLL is enabled, Any write
to PLLn while the PLL is enabled will be discarded.
After setting up the PLL, the PLL is enabled by writing a one to the PLL Enable (PLLEN) bit in
the PLLn register.
14.5.3.2 Disabling the PLL
The PLL is disabled by writing a zero to the PLL Enable (PLLEN) bit in the PLLn register. After
disabling the PLL, the PLL configuration fields becomes writable.
14.5.3.3 PLL Lock
The lock signal for each PLL is available as a PLLLOCKn flag in the PCLKSR register. If the lock
for some reason is lost, the PLLLOCKLOSTn flag in PCLKSR register will be set. An interrupt
can be generated on a 0 to 1 transition of these bits.
14.5.4 Digital Frequency Locked Loop (DFLL) Operation
Rev: 2.1.0.1
The DFLL is controlled by the Digital Frequency Locked Loop Interface (DFLLIF). The DFLL is
disabled by default, but can be enabled to provide a high-frequency source clock for synchronous
and generic clocks.
Features:
• Internal oscillator with no external components
• 20-150MHz frequency in closed loop mode
• Can operate standalone as a high-frequency programmable oscillator in open loop mode
• Can operate as an accurate frequency multiplier against a known frequency in closed loop
mode
• Optional spread-spectrum clock generation
• Very high-frequency multiplication supported - can generate all frequencies from a 32KHz
clock
The DFLL can operate in both open loop mode and closed loop mode. In closed loop mode a
low frequency clock with high accuracy can be used as reference clock to get high accuracy on
the output clock (CLK_DFLL).
To prevent unexpected writes due to software bugs, write access to the configuration registers is
protected by a locking mechanism. For details please refer to the UNLOCK register description.
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Figure 14-2. DFLLIF Block Diagram
14.5.4.1 Enabling the DFLL
The DFLL is enabled by writing a one to the Enable bit (EN) in the DFLLn Configuration Register
(DFLLnCONF). No other bits or fields in DFLLnCONF must be changed simultaneously, or
before the DFLL is enabled.
14.5.4.2 Internal synchronization
Due to multiple clock domains in the DFLLIF, values in the DFLLIF configuration registers need
to be synchronized to other clock domains. The status of this synchronization can be read from
the Power and Clocks Status Register (PCLKSR). Before writing to a DFLLIF configuration register,
the user must check that the DFLLn Synchronization Ready bit (DFLLnRDY) in PCLKSR is
set. When this bit is set, the DFLL can be configured, and CLK_DFLL is ready to be used. Any
write to a DFLLIF configuration register while DFLLnRDY is cleared will be ignored.
Before reading the value in any of the DFLL configuration registers a one must be written to the
Synchronization bit (SYNC) in the DFLLn Synchronization Register (DFLLnSYNC). The DFLL
configuration registers are ready to be read when PCLKSR.DFLLnRDY is set.
14.5.4.3 Disabling the DFLL
The DFLL is disabled by writing a zero to DFLLnCONF.EN. No other bits or fields in DFLLnCONF
must be changed simultaneously.
After disabling the DFLL, PCLKSR.DFLLnRDY will not be set. It is not required to wait for
PCLKSR.DFLLnRDY to be set before re-enabling the DFLL.
14.5.4.4 Open loop operation
After enabling the DFLL, open loop mode is selected by writing a zero to the Mode Selection bit
(MODE) in DFLLnCONF. When operating in open loop mode the output frequency of the DFLL
will be determined by the values written to the Coarse Calibration Value field (COARSE) and the
Fine Calibration Value field (FINE) in the DFLLnCONF register. When writing to COARSE and
DFLL
COARSE
FINE
8
9
CLK_DFLL
IMUL
FMUL 32
CLK_DFLLIF_REF
FREQUENCY
TUNER
DFLLLOCKC
DFLLLOCKLOSTC
DFLLLOCKF
DFLLLOCKLOSTF
DFLLLOCKA
DFLLLOCKLOSTA
CSTEP
FSTEP 8+9 CLK_DFLLIF_DITHER
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FINE, be aware that the output frequency must not exceed the maximum frequency of the
device after the division in the clock generator. It is possible to change the value of COARSE
and FINE, and thereby the output frequency of the DFLL, while the DFLL is enabled and in use.
The DFLL clock is ready to be used when PCLKSR.DFLLnRDY is cleared after enabling the
DFLL.
The frequency range in open loop mode is 20-150MHz, but maximum frequency can be higher,
and the minimum frequency can be lower. The best way to start the DFLL at a specific frequency
in open loop mode is to first configure it for closed loop mode, see Section 14.5.4.5. When a lock
is achieved, read back the COARSE and FINE values and switch to open loop mode using these
values. An alternative approach is to use the Frequency Meter (FREQM) to monitor the DFLL
frequency and adjust the COARSE and FINE values based on measurement results form the
FREQM. Please refer to the FREQM chapter for more information on how to use it. Note that the
output frequency of the DFLL will drift when in open loop mode due to temperature and voltage
changes. Please refer to the Electrical Characteristics chapter for details.
14.5.4.5 Closed loop operation
The DFLL must be correctly configured before closed loop operation can be enabled. After
enabling the DFLL, enable and select a reference clock (CLK_DFLLIF_REF).
CLK_DFLLIF_REF is a generic clock, please refer to Generic Clocks section for details. Then
set the maximum step size allowed in finding the COARSE and FINE values by setting the
Coarse Maximum Step field (CSTEP) and Fine Maximum Step field (FSTEP) in the DFLLn Maximum
Step Register (DFLLnSTEP). A small step size will ensure low overshoot on the output
frequency, but can typically result in longer lock times. A high value might give a big overshoot,
but can typically give faster locking. DFLLnSTEP.CSTEP and DFLLnSTEP.FSTEP must be
lower than 50% of the maximum value of DFLLnCONF.COARSE and DFLLnCONF.FINE
respectively. Then select the multiplication factor in the Integer Multiply Factor field (IMUL) and
the Fractional Multiply field (FMUL) in the DFLLn Multiplier Register (DFLLnMUL). Care must be
taken when choosing IMUL and FMUL so the output frequency does not exceed the maximum
frequency of the device. Start the closed loop mode by writing a one to DFLLnCONF.MODE bit.
The frequency of CLK_DFLL (fDFLL) is given by:
where fREF is the frequency of CLK_DFLLIF_REF. COARSE and FINE in DFLLnCONF are readonly
in closed loop mode, and are controlled by the DFLLIF to meet user specified frequency.
The values in COARSE when the closed loop mode is enabled is used by the frequency tuner as
a starting point for COARSE. Setting COARSE to a value close to the final value will reduce the
time needed to get a lock on COARSE.
Frequency locking
The locking of the frequency in closed loop mode is divided into three stages. In the COARSE
stage the control logic quickly finds the correct value for DFLLnCONF.COARSE and thereby
sets the output frequency to a value close to the correct frequency. The DFLLn Locked on
Coarse Value bit (DFLLnLOCKC) in PCLKSR will be set when this is done. In the FINE stage the
control logic tunes the value in DFLLnCONF.FINE so the output frequency will be very close to
the desired frequency. DFLLn Locked on Fine Value bit (DFLLnLOCKF) in PCLKSR will be set
when this is done. In the ACCURATE stage the DFLL frequency tuning mechanism uses dithering
on the FINE bits to obtain an accurate average output frequency. DFLLn Locked on Accurate
Value bit (DFLLnLOCKA) in PCLKSR will be set when this is done. The ACCURATE stage will
f
DFLL IMUL FMUL
216
+ ----------------- f
REF =
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only be executed if the Dithering Enable bit (DITHER) in DFLLnCONF has been written to a one.
If DITHER is written to a zero DFLLnLOCKA will never occur. If dithering is enabled, the frequency
of the dithering is decided by a generic clock (CLK_DFLLIF_DITHER). This clock has to
be set up correctly before enabling dithering. Please refer to the Generic Clocks section for
details.
Figure 14-3. DFLL Closed loop State Diagram
When dithering is enabled the accuracy of the average output frequency of the DFLL will be
higher. However, the actual frequency will be alternating between two frequencies. If a fixed frequency
is required, the dithering should not be enabled.
Figure 14-4. DFLL Locking in Closed loop
CLK_DFLL is ready to be used when the DFLLn Synchronization Ready bit (DFLLnRDY) in
PCLKSR is set after enabling the DFLL. However, the accuracy of the output frequency depends
on which locks are set.
For lock times, please refer to the Electrical Characteristics chapter.
Measure
fDFLLn
Calculate
new
COARSE
value
DFLLnLOCKC
0
Calculate
new FINE
value
DFLLnLOCKF
0
1 1 DFLLnLOCKA
Calculate
new
dithering
dutycycle
0
Compensate
for
drift
1 DITHER 1
Compensate
for
drift
0
Initial
frequency
Target
frequency
DFLLnLOCKC DFLLnLOCKF DFLLnLOCKA
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Drift compensation
The frequency tuner will automatically compensate for drift in the fDFLL without losing either of the
locks. If the FINE value overflows or underflows, which should normally not happen, but could
occur due to large drift in temperature and voltage, all locks will be lost, and the COARSE and
FINE values will be recalibrated as described earlier. If any lock is lost the corresponding bit in
PCLKSR will be set, DFLLn Lock Lost on Coarse Value bit (DFLLnLOCKLOSTC) for lock lost on
COARSE value, DFLLn Lock Lost on Fine Value bit (DFLLnLOCKLOSTF) for lock lost on FINE
value and DFLLn Lock Lost on Accurate Value bit (DFLLnLOCKLOSTA) for lock lost on ACCURATE
value. The corresponding lock status bit will be cleared when the lock lost bit is set, and
vice versa.
Reference clock stop detection
If CLK_DFLLIF_REF stops or is running at a very slow frequency, the DFLLn Reference Clock
Stopped bit (DFLLnRCS) in PCLKSR will be set. Note that the detection of the clock stop will
take a long time. The DFLLIF operate as if it was in open loop mode if it detects that the reference
clock has stopped. This means that the COARSE and FINE values will be kept constant
while PCLKSR.DFLLnRCS is set. Closed loop mode operation will automatically resume if the
CLK_DFLLIF_REF is restarted, and compensate for any drift during the time CLK_DFLLIF_REF
was stopped. No locks will be lost.
Frequency error measurement
The ratio between CLK_DFLLIF_REF and CLK_DFLL is measured automatically by the DFLLIF.
The difference between this ratio and DFLLnMUL is stored in the Multiplication Ratio Difference
field (RATIODIFF) in the DFLLn Ratio Register (DFLLnRATIO). The relative error on CLK_DFLL
compared to the target frequency can be calculated as follows:
where is the number of reference clock cycles the DFLLIF is using for calculating the
ratio.
14.5.4.6 Dealing with delay in the DFLL
The time from selecting a new frequency until this frequency is output by the DFLL, can be up to
several micro seconds. If the difference between the desired output frequency (CLK_DFLL) and
the frequency of CLK_DFLLIF_REF is small this can lead to an instability in the DFLLIF locking
mechanism, which can prevent the DFLLIF from achieving locks. To avoid this, a chill cycle
where the CLK_DFLL frequency is not measured can be enabled. The chill cycle is enabled by
writing a one to the Chill Cycle Enable (CCEN) bit in the DFLLnCONF register. Enabling chill
cycles might double the lock time,
Another solution to the same problem can be to use less strict lock requirements. This is called
Quick Lock (QL), which is enabled by writing a one to the Quick Lock Enable (QLEN) bit in the
DFLLnCONF register. The QL might lead to bigger spread in the outputted frequency than chill
cycles, but the average output frequency is the same.
If the target frequency is below 40MHz, one of these methods should always be used.
14.5.4.7 Spread Spectrum Generator (SSG)
When the DFLL is used as the main clock source for the device, the EMI radiated from the
device will be synchronous to fDFLL. To provide better Electromagnetic Compatibility (EMC) the
error RATIODIFF fREF
2NUMREF f
DFLL = ------------------------------------------------
2NUMREF
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DFLLIF can provide a clock with the energy spread in the frequency domain. This is done by
adding or subtracting values from the FINE value. SSG is enabled by writing a one to the Enable
bit (EN) in the DFLLn Spread Spectrum Generator Control Register (DFLLnSSG).
A generic clock sets the rate at which the SSG changes the frequency of the DFLL clock to generate
a spread spectrum (CLK_DFLLIF_DITHER). This is the same clock used by the dithering
mechanism. The frequency of this clock should be higher than fREF to ensure that the DFLLIF
can lock. Please refer to the Generic clocks section for details.
Optionally, the clock ticks can be qualified by a Pseudo Random Binary Sequence (PRBS) if the
PRBS bit in DFLLnSSG is one. This reduces the modulation effect of CLK_DFLLIF_DITHER frequency
onto fDFLL.
The amplitude of the frequency variation can be selected by setting the SSG Amplitude field
(AMPLITUDE) in DFLLnSSG. If AMPLITUDE is zero the SSG will toggle on the LSB of the FINE
value. If AMPLITUDE is one the SSG will add the sequence {1,-1, 0} to FINE.
The step size of the SSG is selected by writing to the SSG Step Size field (STEPSIZE) in
DFLLnSSG. STEPSIZE equal to zero or one will result in a step size equal to one. If the step
size is set to n, the output value from the SSG will be incremented/decremented by n on every
tick of the source clock.
The Spread Spectrum Generator is available in both open and closed loop mode.
When spread spectrum is enabled in closed loop mode, and the AMPLITUDE is high, an overflow/underflow
in FINE is more likely to occur.
Figure 14-5. Spread Spectrum Generator Block Diagram.
14.5.4.8 Wake from sleep modes
The DFLLIF may optionally reset its lock bits when waking from a sleep mode which disables the
DFLL. This is configured by the Lose Lock After Wake (LLAW) bit in DFLLnCONF register. If
DFLLnCONF.LLAW is written to zero the DFLL will be re-enabled and start running with the
same configuration as before going to sleep even if the reference clock is not available. The
locks will not be lost. When the reference clock has restarted, the FINE tracking will quickly compensate
for any frequency drift during sleep. If a one is written to DFLLnCONF.LLAW before
going to a sleep mode where the DFLL is turned off, the DFLLIF will lose all its locks when waking
up, and needs to regain these through the full lock sequence.
14.5.4.9 Accuracy
There are mainly three factors that decide the accuracy of the fDFLL. These can be tuned to
obtain maximum accuracy when fine lock is achieved.
Pseudorandom
Binary Sequence Spread Spectrum
Generator
FINE
9
To DFLL CLK_DFLLIF_DITHER
AMPLITUDE,
STEPSIZE PRBS
1
0
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• FINE resolution: The frequency step between two FINE values. This is relatively smaller for
high output frequencies.
• Resolution of the measurement: If the resolution of the measured fDFLL is low, i.e. the ratio
between CLK_DFLL frequency and CLK_DFLLIF_REF is small, then the DFLLIF might lock
at a frequency that is lower than the targeted frequency. It is recommended to use a
reference clock frequency of 32 KHz or lower to avoid this issue for low target frequencies.
• The accuracy of the reference clock.
14.5.4.10 Interrupts
A interrupt can be generated on a zero-to-one transaction on DFLLnLOCKC, DFLLnLOCKF,
DFLLnLOCKA, DFLLnLOCKLOSTC, DFLLnLOCKLOSTF, DFLLnLOCKLOSTA, DFLLnRDY or
DFLLnRCS.
14.5.5 Brown-Out Detection (BOD)
Rev: 1.2.0.0
The Brown-Out Detector monitors the VDDCORE supply pin and compares the supply voltage
to the brown-out detection level.
The BOD is disabled by default, and is enabled by writing to the BOD Control field in the BOD
Control Register (BOD.CTRL). This field can also be updated by flash fuses.
The BOD is powered by VDDIO and will not be powered during Shutdown sleep mode.
To prevent unexpected writes to the BOD register due to software bugs, write access to this register
is protected by a locking mechanism. For details please refer to the UNLOCK register
description.
To prevent further modifications by software, the content of the BOD register can be set as readonly
by writing a one to the Store Final Value bit (BOD.SFV). When this bit is one, software can
not change the BOD register content. This bit is cleared after flash calibration and after a reset
except after a BOD reset.
The brown-out detection level is selected by writing to the BOD Level field in BOD
(BOD.LEVEL). Please refer to the Electrical Characteristics chapter for parametric details.
If the BOD is enabled (BOD.CTRL is one or two) and the supply voltage goes below the detection
level, the Brown-Out Detection bit in the Power and Clocks Status Register
(PCLKSR.BODDET) is set. This bit is cleared when the supply voltage goes above the detection
level. An interrupt request will be generated on a zero-to-one transition on PCLKSR.BODDET if
the Brown-Out Detection bit in the Interrupt Mask Register (IMR.BODDET) is set. This bit is set
by writing a one to the corresponding bit in the Interrupt Enable Register (IER.BODDET).
If BOD.CTRL is one, a BOD reset will be generated when the supply voltage goes below the
detection level. If BOD.CTRL is two, the device will not be reset.
Writing a one to the BOD Hysteresis bit in BOD (BOD.HYST) will add a hysteresis on the BOD
detection level.
Note that the BOD must be disabled before changing BOD.LEVEL, to avoid spurious reset or
interrupt. After enabling the BOD, the BOD output will be masked during one half of a RCSYS
clock cycle and two main clocks cycles to avoid false results.
When the JTAG or aWire is enabled, the BOD reset and interrupt are masked.
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The CTRL, HYST, and LEVEL fields in the BOD Control Register are loaded factory defined calibration
values from flash fuses after a reset. If the Flash Calibration Done bit in the BOD Control
Register (BOD.FCD) is zero, the flash calibration will be redone after any reset, and the
BOD.FCD bit will be set before program execution starts in the CPU. If BOD.FCD is one, the
flash calibration is redone after any reset except for a BOD reset. The BOD.FCD bit is cleared
after a reset, except for a BOD reset. BOD.FCD is set when these fields have been updated after
a flash calibration. It is possible to override the values in the BOD.CTRL, BOD.HYST, and
BOD.LEVEL fields after reset by writing to the BOD Control Register. Please refer to the Fuse
Settings chapter for more details about BOD fuses and how to program the fuses.
Figure 14-6. BOD Block Diagram
14.5.6 Bandgap
Rev: 1.2.0.0
The flash memory, the BOD, and the Temperature Sensor need a stable voltage reference to
operate. This reference voltage is provided by an internal Bandgap voltage reference. This reference
is automatically turned on at start-up and turned off during some sleep modes to save
power. The Bandgap reference is powered by the internal regulator supply voltage and will not
be powered during Shutdown sleep mode. Please refer to the Power Manager chapter for
details.
VDDCORE
POR18 BOD
SCIF
POWER MANAGER(PM) INTC
Reset
Bod
Detected
Enable
BO
D Hyst
BOD
Level
Reset
In et rrupt
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14.5.7 System RC Oscillator (RCSYS)
Rev: 1.1.1.0
The system RC oscillator has a startup time of three cycles, and is always available except in
some sleep modes. Please refer to the Power Manager chapter for details. The system RC oscillator
operates at a nominal frequency of 115kHz, and is calibrated using the Calibration Value
field (CALIB) in the RC Oscillator Calibration Register (RCCR). After a Power-on Reset (POR),
the RCCR.CALIB field is loaded with a factory defined value stored in the Flash fuses. Please
refer to the Fuse setting chapter for more details about RCCR fuses and how to program the
fuses.
If the Flash Calibration Done (FCD) bit in the RCCR is zero at any reset, the flash calibration will
be redone and the RCCR.FCD bit will be set before program execution starts in the CPU. If the
RCCR.FCD is one, the flash calibration will only be redone after a Power-on Reset.
To prevent unexpected writes to RCCR due to software bugs, write access to this register is protected
by a locking mechanism. For details please refer to the UNLOCK register description.
Although it is not recommended to override default factory settings, it is still possible to override
the default values by writing to RCCR.CALIB.
14.5.8 Voltage Regulator (VREG)
Rev: 1.1.0.0
The embedded voltage regulator can be used to provide the VDDCORE voltage from the internal
regulator supply voltage. It is controlled by the Voltage Regulator Calibration Register
(VREGCR). The voltage regulator is enabled by default at start-up but can be disabled by software
if an external voltage is provided on the VDDCORE pin. The VREGCR also contains bits to
control the POR18 detector and the POR33 detector.
14.5.8.1 Register protection
To prevent unexpected writes to VREGCR due to software bugs, write access to this register is
protected by a locking mechanism. For details please refer to the UNLOCK register description.
To prevent further modifications by software, the content of the VREGCR register can be set as
read-only by writing a one to the Store Final Value bit (VREGCR.SFV). Once this bit is set, software
can not change the VREGCR content until a Power-on Reset (POR) is applied.
14.5.8.2 Controlling voltage regulator output
The voltage regulator is always enabled at start-up, i.e. after a POR or when waking up from
Shutdown mode. It can be disabled by software by writing a zero to the Enable bit
(VREGCR.EN). This bit is set after a POR. Because of internal synchronization, the voltage regulator
is not immediately enabled or disabled. The actual state of the voltage regulator can be
read from the ON bit (VREGCR.ON).
The voltage regulator output level is controlled by the Select VDD field (SELVDD) in VREGCR.
The default value of this field corresponds to a regulator output voltage of 1.8V. Other values of
this field are not defined, and it is not recommended to change the value of this field.
The Voltage Regulator OK bit (VREGCR.VREGOK) bit indicates when the voltage regulator output
has reached the voltage threshold level.
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14.5.8.3 Factory calibration
After a Power-on Reset (POR) the VREGCR.CALIB field is loaded with a factory defined calibration
value. This value is chosen so that the normal output voltage of the regulator after a powerup
is 1.8V.
Although it is not recommended to override default factory settings, it is still possible to override
these default values by writing to VREGCR.CALIB.
If the Flash Calibration Done bit in VREGCR (VREGCR.FCD) is zero, the flash calibration will be
redone after any reset, and the VREGCR.FCD bit will be set before program execution starts in
the CPU. If VREGCR.FCD is one, the flash calibration will only be redone after a POR.
14.5.8.4 POR33 control
VREGCR includes control bits for the Power-on Reset 3.3V (POR33) detector that monitors the
internal regulator supply voltage. The POR33 detector is enabled by default but can be disabled
by software to reduce power consumption. The 3.3V Supply Monitor (SM33) can then be used to
monitor the regulator power supply.
The POR33 detector is disabled by writing a zero to the POR33 Enable bit
(VREGCR.POR33EN). Because of internal synchronisation, the POR33 detector is not immediately
enabled or disabled. The actual state of the POR33 detector can be read from the POR33
Status bit (VREGCR.POR33STATUS).
The 32kHz RC oscillator (RC32K) must be enabled before disabling the POR33 detector. Once
the POR33 detector has been disabled, the RC32K oscillator can be disabled again.
To avoid spurious resets, it is mandatory to mask the Power-on Reset when enabling or disabling
the POR33 detector. The Power-on Reset generated by the POR33 detector can be
ignored by writing a one to the POR33 Mask bit (VREGCR.POR33MASK). Because of internal
synchronization, the masking is not immediately effective, so software should wait for the
VREGCR.POR33MASK to read as a one before assuming the masking is effective.
The output of the POR33 detector is zero if the internal regulator supply voltage is below the
POR33 power-on threshold level, and one if the internal regulator supply voltage is above the
POR33 power-on threshold level. This output (before masking) can be read from the POR33
Value bit (VREGCR.POR33VALUE).
14.5.8.5 POR18 control
VREGCR includes control bits for the Power-on Reset 1.8V (POR18) detector that monitors the
VDDCORE voltage. The POR18 detector is enabled by default but can be disabled by software
to reduce power consumption.
The POR18 detector is disabled by writing a zero to the POR18 Enable bit
(VREGCR.POR18EN). Because of internal synchronization, the POR18 detector is not immediately
enabled or disabled. The actual state of the POR18 detector can be read from the POR18
Status bit (VREGCR.POR18STATUS).
Please note that the POR18 detector cannot be disabled while the JTAG or aWire debug interface
is used. Writing a zero to VREGCR.POR18EN bit will have no effect.
To avoid spurious resets, it is mandatory to mask the Power-on Reset when enabling or disabling
the POR18 detector. The Power-on Reset generated by the POR18 detector can be
ignored by writing a one to the POR18 Mask bit (VREGCR.POR18MASK). Because of internal
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synchronisation, the masking is not immediately effective, so software should wait for the
VREGCR.POR18MASK to read as one before assuming the masking is effective.
The output of the POR18 detector is zero if the VDDCORE voltage is below the POR18 poweron
threshold level, and one if the VDDCORE voltage is above the POR18 power-on threshold
level. The output of the POR18 detector (before masking) can be read from the POR18 Value bit
(VREGCR.POR18VALUE).
14.5.9 3.3 V Supply Monitor (SM33)
Rev: 1.1.0.0
The 3.3V supply monitor is a specific voltage detector for the internal regulator supply voltage. It
will indicate if the internal regulator supply voltage is above the minimum required input voltage
threshold. The user can choose to generate either a Power-on Reset (POR) and an interrupt
request, or only an interrupt request, when the internal regulator supply voltage drops below this
threshold.
Please refer to the Electrical Characteristics chapter for parametric details.
14.5.9.1 Register protection
To prevent unexpected writes to SM33 register due to software bugs, write access to this register
is protected by a locking mechanism. For details please refer to the UNLOCK register
description.
To prevent further modifications by software, the content of the register can be set as read-only
by writing a one to the Store Final Value bit (SM33.SFV). When this bit is one, software can not
change the SM33 register content until the device is reset.
14.5.9.2 Operating modes
The SM33 is disabled by default and is enabled by writing to the Supply Monitor Control field in
the SM33 control register (SM33.CTRL). The current state of the SM33 can be read from the
Supply Monitor On Indicator bit in SM33 (SM33.ONSM). Enabling the SM33 will disable the
POR33 detector.
The SM33 can operate in continuous mode or in sampling mode. In sampling mode, the SM33 is
periodically enabled for a short period of time, just enough to make a a measurement, and then
disabled for a longer time to reduce power consumption.
By default, the SM33 operates in sampling mode during DeepStop and Static mode and in continuous
mode for other sleep modes. Sampling mode can also be forced during sleep modes
other than DeepStop and Static, and during normal operation, by writing a one to the Force
Sampling Mode bit in the SM33 register (SM33.FS).
The user can select the sampling frequency by writing to the Sampling Frequency field in SM33
(SM33.SAMPFREQ). The sampling mode uses the 32kHz RC oscillator (RC32K) as clock
source. The 32kHz RC oscillator is automatically enabled when the SM33 operates in sampling
mode.
14.5.9.3 Interrupt and reset generation
If the SM33 is enabled (SM33.CTRL is one or two) and the regulator supply voltage drops below
the SM33 threshold, the SM33DET bit in the Power and Clocks Status Register
(PCLKSR.SM33DET) is set. This bit is cleared when the supply voltage goes above the threshold.
An interrupt request is generated on a zer-to-one transition of PCLKSR.SM33DET if the
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Supply Monitor 3.3V Detection bit in the Interrupt Mask Register (IMR.SM33DET) is set. This bit
is set by writing a one to the corresponding bit in the Interrupt Enable Register (IER.SM33DET).
If SM33.CTRL is one, a POR will be generated when the voltage drops below the threshold. If
SM33.CTRL is two, the device will not be reset.
14.5.9.4 Factory calibration
After a reset the SM33.CALIB field is loaded with a factory defined value. This value is chosen
so that the nominal threshold value is 1.75V. The flash calibration is redone after any reset, and
the Flash Calibration Done bit in SM33 (SM33.FCD) is set before program execution starts in the
CPU.
Although it is not recommended to override default factory settings, it is still possible to override
the default value by writing to SM33.CALIB
14.5.10 Temperature Sensor
Rev: 1.0.0.0
The Temperature Sensor is connected to an ADC channel, please refer to the ADC chapter for
details. It is enabled by writing one to the Enable bit (EN) in the Temperature Sensor Configuration
Register (TSENS). The Temperature Sensor can not be calibrated.
Please refer to the Electrical Characteristics chapter for more details.
14.5.11 120MHz RC Oscillator (RC120M)
Rev: 1.1.0.0
The 120MHz RC Oscillator can be used as source for the main clock in the device, as described
in the Power Manager chapter. The oscillator can also be used as source for the generic clocks,
as described in Generic Clock section. The RC120M must be enabled before it is used as a
source clock. To enable the clock, the user must write a one to the Enable bit in the 120MHz RC
Oscillator Control Register (RC120MCR.EN), and read back the RC120MCR register until the
EN bit reads one. The clock is disabled by writing a zero to RC120MCR.EN. The EN bit must be
read back as zero before the RC120M is re-enabled. If not, undefined behavior may occur.
The oscillator is automatically disabled in certain sleep modes to reduce power consumption, as
described in the Power Manager chapter.
14.5.12 Backup Registers (BR)
Rev: 1.0.0.1
Four 32-bit backup registers are available to store values when the device is in Shutdown
mode. These registers will keep their content even when the VDDCORE supply and the internal
regulator supply voltage supplies are removed. The backup registers can be accessed by reading
from and writing to the BR0, BR1, BR2, and BR3 registers.
After writing to one of the backup registers the user must wait until the Backup Register Interface
Ready bit in tne Power and Clocks Status Register (PCLKSR.BRIFARDY) is set before writing to
another backup register. Writes to the backup register while PCLKSR.BRIFARDY is zero will be
discarded. An interrupt can be generated on a zero-to-one transition on PCLKSR.BRIFARDY if
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the BRIFARDY bit in the Interrupt Mask Register (IMR.BRIFARDY) is set. This bit is set by writing
a one to the corresponding bit in the Interrupt Enable Register (IER.BRIFARDY).
After powering up the device the Backup Register Interface Valid bit in PCLKSR (PCLKSR.BRIFAVALID)
is cleared, indicating that the content of the backup registers has not been written and
contains the reset value. After writing to one of the backup registers the PCLKSR.BRIFAVALID
bit is set. During writes to the backup registers (when BRIFARDY is zero) BRIFAVALID will be
zero. If a reset occurs when BRIFARDY is zero, BRIFAVALID will be cleared after the reset, indicating
that the content of the backup registers is not valid. If BRIFARDY is one when a reset
occurs, BRIFAVALID will be one and the content is the same as before the reset.
The user must ensure that BRIFAVALID and BRIFARDY are both set before reading the backup
register values.
14.5.13 32kHz RC Oscillator (RC32K)
Rev: 1.1.0.0
The RC32K can be used as source for the generic clocks, as described in The Generic Clocks
section.
The 32kHz RC oscillator (RC32K) is forced on after reset, and output on PA20. The clock is
available on the pad until the PPCR.FRC32 bit in the Power Manager has been cleared or a different
peripheral function has been chosen on PA20 (PA20 will start with peripheral function F
by default). Note that the forcing will only enable the clock output. To be able to use the RC32K
normally the oscillator must be enabled as described below.
The oscillator is enabled by writing a one to the Enable bit in the 32kHz RC Oscillator Configuration
Register (RC32KCR.EN) and disabled by writing a zero to RC32KCR.EN. The oscillator is
also automatically enabled when the sampling mode is requested for the SM33. In this case,
writing a zero to RC32KCR.EN will not disable the RC32K until the sampling mode is no longer
requested.
14.5.14 Generic Clock Prescalers
Rev: 1.0.0.0
The generic clocks can be sourced by two special prescalers to increase the generic clock frequency
precision.
These prescalers are named the High Resolution Prescaler (HRP) and the Fractional Prescaler
(FP).
14.5.14.1 High resolution prescaler
The HRP is a 24-bit counter that can generate a very accurate clock waveform. The clock
obtained has 50% duty cycle.
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Figure 14-7. High Resolution Prescaler Generation
The HRP is enabled by writing a one to the High Resolution Prescaler Enable (HRPEN) bit in the
High Resolution Prescaler Control Register (HRPCR).
The user can select a clock source for the HRP by writing to the Clock Selection (CKSEL) field of
the HRPCR register.
The user must configure the High Resolution Prescaler Clock (HRPCLK) frequency by writing to
the High Resolution Count (HRCOUNT) field of the High Resolution Counter (HRPCR) register.
This results in the output frequency:
fHRPCLK = fSRC / (2*(HRCOUNT+1))
The CKSEL field can not be changed dynamically but the HRCOUNT field can be changed onthe-fly.
14.5.14.2 Fractional prescaler
The FP generates a clock whose average frequency is more precise than the HRP. However,
this clock frequency is subject to jitter around the target clock frequency. This jitter influence can
be decreased by dividing this clock with the GCLK divider. Moreover the duty cycle of this clock
is not precisely 50%.
Figure 14-8. Fractional Prescaler Generation
The FP is enabled by writing a one to the FPEN bit in the Fractional Prescaler Control Register
(FPCR).
The user can select a clock source for the FP by writing to the CKSEL field of the FPCR register.
Divider
CKSEL
HRPCLK
HRCOUNT
Mask
HRPEN
Divider
CKSEL
FPCLK
FPDIV
Mask
FPMUL FPEN
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The user must configure the FP frequency by writing to the FPMUL and FPDIV fields of the
FPMUL and FPDIV registers. FPMUL and FPDIV must not be equal to zero and FPDIV must be
greater or equal to FPMUL. This results in the output frequency:
fFPCLK = fSRC * FPMUL/ (2*FPDIV)
The CKSEL field can not be changed dynamically but the FPMUL and FPDIV fields can be
changed on-the-fly.
• Jitter description
As described in Figure 14-9, the CLKFP half period lengths are integer multiples of the source
clock period but are not always equals. However the difference between the low level half period
length and the high level half period length is at the most one source clock period.
This induces when FPDIV is not an integer multiple of FPMUL a jitter on the FPCLK. The more
the FPCLK frequency is low, the more the jitter incidence is reduced.
Figure 14-9. Fractional Prescaler Jitter Examples
14.5.15 Generic Clocks
Rev: 1.1.0.0
Timers, communication modules, and other modules connected to external circuitry may require
specific clock frequencies to operate correctly. The SCIF defines a number of generic clocks that
can provide a wide range of accurate clock frequencies.
Each generic clock runs from either clock source listed in the “Generic Clock Sources” table in
the SCIF Module Configuration section. The selected source can optionally be divided by any
even integer up to 512. Each clock can be independently enabled and disabled, and is also
automatically disabled along with peripheral clocks by the Sleep Controller in the Power
Manager.
SRC clock
FPCLK
FMUL= 5
FDIV=5
FMUL=3
FDIV=10
FMUL=7
FDIV=9
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Figure 14-10. Generic Clock Generation
14.5.15.1 Enabling a generic clock
A generic clock is enabled by writing a one to the Clock Enable bit (CEN) in the Generic Clock
Control Register (GCCTRL). Each generic clock can individually select a clock source by writing
to the Oscillator Select field (OSCSEL). The source clock can optionally be divided by writing a
one to the Divide Enable bit (DIVEN) and the Division Factor field (DIV), resulting in the output
frequency:
where fSRC is the frequency of the selected source clock, and fGCLK is the output frequency of the
generic clock.
14.5.15.2 Disabling a generic clock
A generic clock is disabled by writing a zero to CEN or entering a sleep mode that disables the
PB clocks. In either case, the generic clock will be switched off on the first falling edge after the
disabling event, to ensure that no glitches occur. After CEN has been written to zero, the bit will
still read as one until the next falling edge occurs, and the clock is actually switched off. When
writing a zero to CEN the other bits in GCCTRL should not be changed until CEN reads as zero,
to avoid glitches on the generic clock. The generic clocks will be automatically re-enabled when
waking from sleep.
14.5.15.3 Changing clock frequency
When changing the generic clock frequency by changing OSCSEL or DIV, the clock should be
disabled before being re-enabled with the new clock source or division setting. This prevents
glitches during the transition.
14.5.15.4 Generic clock allocation
The generic clocks are allocated to different functions as shown in the “Generic Clock Allocation”
table in the SCIF Module Configuration section.
14.5.16 Interrupts
The SCIF has the following interrupt sources:
• AE - Access Error:
– A protected SCIF register was accessed without first being correctly unlocked.
Divider
OSCSEL
Generic Clock
DIV
0
1
DIVEN
Mask
CEN
Sleep Controller
fSRC fGCLK
Generic
Clock
Sources
f
GCLK
f
SRC
2 DIV + 1 = ----------------------------
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• PLLLOCK - PLL Lock
– A 0 to 1 transition on the PCLKSR.PLLLOCK bit is detected.
• PLLLOCKLOST - PLL Lock Lost
– A to 1 transition on the PCLKSR.PLLLOCKLOST bit is detected.
• BRIFARDY - Backup Register Interface Ready.
– A 0 to 1 transition on the PCLKSR.BRIFARDY bit is detected.
• DFLL0RCS - DFLL Reference Clock Stopped:
– A 0 to 1 transition on the PCLKSR.DFLLRCS bit is detected.
• DFLL0RDY - DFLL Ready:
– A 0 to 1 transition on the PCLKSR.DFLLRDY bit is detected.
• DFLL0LOCKLOSTA - DFLL lock lost on Accurate value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTA bit is detected.
• DFLL0LOCKLOSTF - DFLL lock lost on Fine value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTF bit is detected.
• DFLL0LOCKLOSTC - DFLL lock lost on Coarse value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTC bit is detected.
• DFLL0LOCKA - DFLL Locked on Accurate value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKA bit is detected.
• DFLL0LOCKF - DFLL Locked on Fine value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKF bit is detected.
• DFLL0LOCKC - DFLL Locked on Coarse value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKC bit is detected.
• BODDET - Brown out detection:
– A 0 to 1 transition on the PCLKSR.BODDET bit is detected.
• SM33DET - Supply Monitor 3.3V Detector:
– A 0 to 1 transition on the PCLKSR.SM33DET bit is detected.
• VREGOK - Voltage Regulator OK:
– A 0 to 1 transition on the PCLKSR.VREGOK bit is detected.
• OSC0RDY - Oscillator Ready:
– A 0 to 1 transition on the PCLKSR.OSC0RDY bit is detected.
• OSC32RDY - 32KHz Oscillator Ready:
– A 0 to 1 transition on the PCLKSR.OSC32RDY bit is detected.
The interrupt sources will generate an interrupt request if the corresponding bit in the Interrupt
Mask Register is set. The interrupt sources are ORed together to form one interrupt request. The
SCIF will generate an interrupt request if at least one of the bits in the Interrupt Mask Register
(IMR) is set. Bits in IMR are set by writing a one to the corresponding bit in the Interrupt Enable
Register (IER), and cleared by writing a one to the corresponding bit in the Interrupt Disable
Register (IDR). The interrupt request remains active until the corresponding bit in the Interrupt
Status Register (ISR) is cleared by writing a one to the corresponding bit in the Interrupt Clear
Register (ICR). Because all the interrupt sources are ORed together, the interrupt request from
the SCIF will remain active until all the bits in ISR are cleared.
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14.6 User Interface
Table 14-2. SCIF Register Memory Map
Offset Register Register Name Access Reset
0x0000 Interrupt Enable Register IER Write-only 0x00000000
0x0004 Interrupt Disable Register IDR Write-only 0x00000000
0x0008 Interrupt Mask Register IMR Read-only 0x00000000
0x000C Interrupt Status Register ISR Read-only 0x00000000
0x0010 Interrupt Clear Register ICR Write-only 0x00000000
0x0014 Power and Clocks Status Register PCLKSR Read-only 0x00000000
0x0018 Unlock Register UNLOCK Write-only 0x00000000
0x001C Oscillator 0 Control Register OSCCTRL0 Read/Write 0x00000000
0x0020 Oscillator 32 Control Register OSCCTRL32 Read/Write 0x00000004
0x0024 DFLL Config Register DFLL0CONF Read/Write 0x00000000
0x0028 DFLL Multiplier Register DFLL0MUL Write-only 0x00000000
0x002C DFLL Step Register DFLL0STEP Write-only 0x00000000
0x0030 DFLL Spread Spectrum Generator Control
Register DFLL0SSG Write-only 0x00000000
0x0034 DFLL Ratio Register DFLL0RATIO Read-only 0x00000000
0x0038 DFLL Synchronization Register DFLL0SYNC Write-only 0x00000000
0x003C BOD Level Register BOD Read/Write -(2)
0x0044 Voltage Regulator Calibration Register VREGCR Read/Write -(2)
0x0048 System RC Oscillator Calibration Register RCCR Read/Write -(2)
0x004C Supply Monitor 33 Calibration Register SM33 Read/Write -(2)
0x0050 Temperature Sensor Calibration Register TSENS Read/Write 0x00000000
0x0058 120MHz RC Oscillator Control Register RC120MCR Read/Write 0x00000000
0x005C-0x0068 Backup Registers BR Read/Write 0x00000000
0x006C 32kHz RC Oscillator Control Register RC32KCR Read/Write 0x00000000
0x0070 Generic Clock Control0 GCCTRL0 Read/Write 0x00000000
0x0074 Generic Clock Control1 GCCTRL1 Read/Write 0x00000000
0x0078 Generic Clock Control2 GCCTRL2 Read/Write 0x00000000
0x007C Generic Clock Control3 GCCTRL3 Read/Write 0x00000000
0x0080 Generic Clock Control4 GCCTRL4 Read/Write 0x00000000
0x0084 Generic Clock Control5 GCCTRL5 Read/Write 0x00000000
0x0088 Generic Clock Control6 GCCTRL6 Read/Write 0x00000000
0x008C Generic Clock Control7 GCCTRL7 Read/Write 0x00000000
0x0090 Generic Clock Control8 GCCTRL8 Read/Write 0x00000000
0x0094 Generic Clock Control9 GCCTRL9 Read/Write 0x00000000
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Note: 1. The reset value is device specific. Please refer to the Module Configuration section at the end of this chapter.
2. The reset value of this register depends on factory calibration.
0x0098 PLL0 Control Register PLL0 Read/Write 0x00000000
0x009C High Resolution Prescaler Control Register HRPCR Read/Write 0x00000000
0x00A0 Fractional Prescaler Control Register FPCR Read/Write 0x00000000
0x00A4 Fractional Prescaler Multiplier Register FPMUL Read/Write 0x00000000
0x00A8 Fractional Prescaler DIVIDER Register FPDIV Read/Write 0x00000000
0x03BC Commonly used Modules Version Register CMVERSION Read-only -(1)
0x03C0 Generic Clock Prescaler Version Register GCLKPRESCVERSION Read-only -(1)
0x03C4 PLL Version Register PLLVERSION Read-only -(1)
0x03C8 Oscillator0 Version Register OSC0VERSION Read-only -(1)
0x03CC 32 KHz Oscillator Version Register OSC32VERSION Read-only -(1)
0x03D0 DFLL Version Register DFLLIFVERSION Read-only -(1)
0x03D4 BOD Version Register BODIFAVERSION Read-only -(1)
0x03D8 Voltage Regulator Version Register VREGIFBVERSION Read-only -(1)
0x03DC System RC Oscillator Version Register RCOSCIFAVERSION Read-only -(1)
0x03E0 3.3V Supply Monitor Version Register SM33IFAVERSION Read-only -(1)
0x03E4 Temperature Sensor Version Register TSENSIFAVERSION Read-only -(1)
0x03EC 120MHz RC Oscillator Version Register RC120MIFAVERSION Read-only -(1)
0x03F0 Backup Register Interface Version Register BRIFAVERSION Read-only -(1)
0x03F4 32kHz RC Oscillator Version Register RC32KIFAVERSION Read-only -(1)
0x03F8 Generic Clock Version Register GCLKVERSION Read-only -(1)
0x03FC SCIF Version Register VERSION Read-only -(1)
Table 14-2. SCIF Register Memory Map
Offset Register Register Name Access Reset
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14.6.1 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x0000
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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14.6.2 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x0004
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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14.6.3 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x0008
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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14.6.4 Interrupt Status Register
Name: ISR
Access Type: Read-only
Offset: 0x000C
Reset Value: 0x00000000
0: The corresponding interrupt is cleared.
1: The corresponding interrupt is pending.
A bit in this register is cleared when the corresponding bit in ICR is written to one.
A bit in this register is set when the corresponding interrupt occurs.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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14.6.5 Interrupt Clear Register
Name: ICR
Access Type: Write-only
Offset: 0x0010
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in ISR.
31 30 29 28 27 26 25 24
AE - - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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14.6.6 Power and Clocks Status Register
Name: PCLKSR
Access Type: Read-only
Offset: 0x0014
Reset Value: 0x00000000
• BRIFAVALID: Backup Register Interface Valid
0: The values in the backup registers are not valid.
1: The values in the backup registers are valid.
• PLLL0LOCKLOST: PLL0 lock lost value
0: PLL0 has not lost it’s lock or has never been enabled.
1: PLL0 has lost it’s lock, either by disabling the PLL0 or due to faulty operation.
• PLL0LOCK: PLL0 Locked on Accurate value
0: PLL0 is unlocked on accurate value.
1: PLL0 is locked on accurate value, and is ready to be selected as clock source with an accurate output clock.
• BRIFARDY: Backup Register Interface Ready
0: The backup register interface is busy updating the backup registers. Writes to BRn will be discarded.
1: The backup register interface is ready to accept new writes to the backup registers.
• DFLL0RCS: DFLL0 Reference Clock Stopped
0: The DFLL reference clock is running, or has never been enabled.
1: The DFLL reference clock has stopped or is too slow.
• DFLL0RDY: DFLL0 Synchronization Ready
0: Read or write to DFLL registers is invalid
1: Read or write to DFLL registers is valid
• DFLL0LOCKLOSTA: DFLL0 Lock Lost on Accurate Value
0: DFLL has not lost its Accurate lock or has never been enabled.
1: DFLL has lost its Accurate lock, either by disabling the DFLL or due to faulty operation.
• DFLL0LOCKLOSTF: DFLL0 Lock Lost on Fine Value
0: DFLL has not lost its Fine lock or has never been enabled.
1: DFLL has lost its Fine lock, either by disabling the DFLL or due to faulty operation.
31 30 29 28 27 26 25 24
- BRIFAVALID - - - - - -
23 22 21 20 19 18 17 16
----- PLLLOCKLO
ST0 PLLLOCK0 BRIFARDY
15 14 13 12 11 10 9 8
DFLL0RCS DFLL0RDY DFLL0LOCK
LOSTA
DFLL0LOCK
LOSTF
DFLL0LOCK
LOSTC
DFLL0LOCK
A
DFLL0LOCK
F
DFLL0LOCK
C
76543210
BODDET SM33DET VREGOK - - - OSC0RDY OSC32RDY
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• DFLL0LOCKLOSTC: DFLL0 Lock Lost on Coarse Value
0: DFLL has not lost its Coarse lock or has never been enabled.
1: DFLL has lost its Coarse lock, either by disabling the DFLL or due to faulty operation.
• DFLL0LOCKA: DFLL0 Locked on Accurate Value
0: DFLL is unlocked on Accurate value.
1: DFLL is locked on Accurate value, and is ready to be selected as clock source with an accurate output clock.
• DFLL0LOCKF: DFLL0 Locked on Fine Value
0: DFLL is unlocked on Fine value.
1: DFLL is locked on Fine value, and is ready to be selected as clock source with a high accuracy on the output clock.
• DFLL0LOCKC: DFLL0 Locked on Coarse Value
0: DFLL is unlocked on Coarse value.
1: DFLL is locked on Coarse value, and is ready to be selected as clock source with medium accuracy on the output clock.
• BODDET: Brown-Out Detection
0: No BOD Event.
1: BOD has detected that the supply voltage is below the BOD reference value.
• SM33DET: Supply Monitor 3.3V Detector
0: SM33 not enabled or the supply voltage is above the SM33 threshold.
1: SM33 enabled and the supply voltage is below the SM33 threshold.
• VREGOK: Voltage Regulator OK
0: Voltage regulator not enabled or not ready.
1: Voltage regulator has reached its output threshold value after being enabled.
• OSC0RDY: OSC0 Ready
0: Oscillator not enabled or not ready.
1: Oscillator is stable and ready to be used as clock source.
• OSC32RDY: 32 KHz oscillator Ready
0: OSC32K not enabled or not ready.
1: OSC32K is stable and ready to be used as clock source.
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14.6.7 Unlock Register
Name: UNLOCK
Access Type: Write-only
Offset: 0x0018
Reset Value: 0x00000000
To unlock a write protected register, first write to the UNLOCK register with the address of the register to unlock in the ADDR
field and 0xAA in the KEY field. Then, in the next PB access write to the register specified in the ADDR field.
The LOCK is by default off. To turn on the LOCK, first write 0xAA to the KEY field and UNLOCK address offset to the ADDR field
in the UNLOCK register, followed by writing 0x5A5A5A5A to the UNLOCK register. To turn off the LOCK, first write 0xAA to the
KEY field and UNLOCK address offset to the ADDR field in the UNLOCK register, followed by writing 0xA5AA5A55 to the
UNLOCK register.
• KEY: Unlock Key
Write this bit field to 0xAA to enable unlock.
• ADDR: Unlock Address
Write the address offset of the register to unlock to this field.
31 30 29 28 27 26 25 24
KEY
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - ADDR[9:8]
76543210
ADDR[7:0]
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14.6.8 Oscillator Control Register
Name: OSCCTRLn
Access Type: Read/Write
Reset Value: 0x00000000
• OSCEN: Oscillator Enable
0: The oscillator is disabled.
1: The oscillator is enabled.
• STARTUP: Oscillator Start-up Time
Select start-up time for the oscillator. Please refer to the “Oscillator Startup Time” table in the SCIF Module Configuration
section for details.
• AGC: Automatic Gain Control
For test purposes.
• GAIN: Gain
Selects the gain for the oscillator. Please refer to the “Oscillator Gain Settings” table in the SCIF Module Configuration section
for details.
• MODE: Oscillator Mode
0: External clock connected on XIN. XOUT can be used as general-purpose I/O (no crystal).
1: Crystal is connected to XIN/XOUT.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - OSCEN
15 14 13 12 11 10 9 8
- - - - STARTUP[3:0]
76543210
- - - - AGC GAIN[1:0] MODE
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14.6.9 32KHz Oscillator Control Register
Name: OSCCTRL32
Access Type: Read/Write
Reset Value: 0x00000004
Note: This register is only reset by Power-On Reset
• RESERVED
This bit must always be written to zero.
• STARTUP: Oscillator Start-up Time
Select start-up time for 32 KHz oscillator
31 30 29 28 27 26 25 24
RESERVED -------
23 22 21 20 19 18 17 16
- - - - - STARTUP[2:0]
15 14 13 12 11 10 9 8
- - - - - MODE[2:0]
76543210
- - - - EN1K EN32K PINSEL OSC32EN
Table 14-3. Start-up Time for 32 KHz Oscillator
STARTUP
Number of RCSYS Clock
Cycle
Approximative Equivalent Time
(RCOSC = 115 kHz)
00 0
1 128 1.1 ms
2 8192 72.3 ms
3 16384 143 ms
4 65536 570 ms
5 131072 1.1 s
6 262144 2.3 s
7 524288 4.6 s
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• MODE: Oscillator Mode
• EN1K: 1 KHz output Enable
0: The 1 KHz output is disabled.
1: The 1 KHz output is enabled.
• EN32K: 32 KHz output Enable
0: The 32 KHz output is disabled.
1: The 32 KHz output is enabled.
• PINSEL: Pins Select
0: Default pins used.
1: Alternate pins: XIN32_2 pin is used instead of XIN32 pin, XOUT32_2 pin is used instead of XOUT32.
• OSC32EN: 32 KHz Oscillator Enable
0: The 32 KHz Oscillator is disabled
1: The 32 KHz Oscillator is enabled
Table 14-4. Operation Mode for 32 KHz Oscillator
MODE Description
0 External clock connected to XIN32, XOUT32 can be used as general-purpose I/O (no crystal)
1 Crystal mode. Crystal is connected to XIN32/XOUT32.
2 Reserved
3 Reserved
4 Crystal and high current mode. Crystal is connected to XIN32/XOUT32.
5 Reserved
6 Reserved
7 Reserved
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14.6.10 DFLLn Configuration Register
Name: DFLLnCONF
Access Type: Read/Write
Reset Value: 0x00000000
• COARSE: Coarse Calibration Value
Set the value of the coarse calibration register. If in closed loop mode, this field is Read-only.
• FINE: FINE Calibration Value
Set the value of the fine calibration register. If in closed loop mode, this field is Read-only.
• QLEN: Quick Lock Enable
0: Quick Lock is disabled.
1: Quick Lock is enabled.
• CCEN: Chill Cycle Enable
0: Chill Cycle is disabled.
1: Chill Cycle is enabled.
• LLAW: Lose Lock After Wake
0: Locks will not be lost after waking up from sleep modes.
1: Locks will be lost after waking up from sleep modes where the DFLL clock has been stopped.
• DITHER: Enable Dithering
0: The fine LSB input to the VCO is constant.
1: The fine LSB input to the VCO is dithered to achieve sub-LSB approximation to the correct multiplication ratio.
• MODE: Mode Selection
0: The DFLL is in open loop operation.
1: The DFLL is in closed loop operation.
• EN: Enable
0: The DFLL is disabled.
1: The DFLL is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
COARSE[7:0]
23 22 21 20 19 18 17 16
- - - - - - - FINE[8]
15 14 13 12 11 10 9 8
FINE[7:0]
76543210
- QLEN CCEN - LLAW DITHER MODE EN
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14.6.11 DFLLn Multiplier Register
Name: DFLLnMUL
Access Type: Read/Write
Reset Value: 0x00000000
• IMUL: Integer Multiply Factor
This field, together with FMUL, determines the ratio between fDFLL and fREFthe DFLL. IMUL is the integer part, while the FMUL is
the fractional part.
In open loop mode, writing to this register has no effect.
• FMUL: Fractional Multiply Factor
This field, together with IMUL, determines the ratio between fDFLL and fREFthe DFLL. IMUL is the integer part, while the FMUL is
the fractional part.
In open loop mode, writing to this register has no effect.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
IMUL[15:8]
23 22 21 20 19 18 17 16
IMUL[7:0]
15 14 13 12 11 10 9 8
FMUL[15:8]
76543210
FMUL[7:0]
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14.6.12 DFLLn Maximum Step Register
Name: DFLLnSTEP
Access Type: Read/Write
Reset Value: 0x00000000
• FSTEP: Fine Maximum Step
This indicates the maximum step size during fine adjustment in closed-loop mode. When adjusting to a new frequency, the
expected overshoot of that frequency depends on this step size.
• CSTEP: Coarse Maximum Step
This indicates the maximum step size during coarse adjustment in closed-loop mode. When adjusting to a new frequency, the
expected overshoot of that frequency depends on this step size.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
- - - - - - - FSTEP[8]
23 22 21 20 19 18 17 16
FSTEP[7:0]
15 14 13 12 11 10 9 8
--------
76543210
CSTEP[7:0]
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14.6.13 DFLLn Spread Spectrum Generator Control Register
Name: DFLLnSSG
Access Type: Read/Write
Reset Value: 0x00000000
• STEPSIZE: SSG Step Size
Sets the step size of the spread spectrum.
• AMPLITUDE: SSG Amplitude
Sets the amplitude of the spread spectrum.
• PRBS: Pseudo Random Bit Sequence
0: Each spread spectrum frequency is applied at constant intervals
1: Each spread spectrum frequency is applied at pseudo-random intervals
• EN: Enable
0: SSG is disabled.
1: SSG is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
- -------
23 22 21 20 19 18 17 16
- - - STEPSIZE[4:0]
15 14 13 12 11 10 9 8
- - - AMPLITUDE[4:0]
76543210
- - - - - - PRBS EN
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14.6.14 DFLLn Ratio Register
Name: DFLLnRATIO
Access Type: Read-only
Reset Value: 0x00000000
• RATIODIFF: Multiplication Ratio Difference
In closed-loop mode, this field indicates the error in the ratio between the VCO frequency and the target frequency.
• NUMREF: Numerical Reference
The number of reference clock cycles used to measure the VCO frequency equals 2^NUMREF.
31 30 29 28 27 26 25 24
RATIODIFF[15:8]
23 22 21 20 19 18 17 16
RATIODIFF[7:0]
15 14 13 12 11 10 9 8
- -------
76543210
- - - NUMREF[4:0]
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14.6.15 DFLLn Synchronization Register
Name: DFLLnSYNC
Access Type: Write-only
Reset Value: 0x00000000
• SYNC: Synchronization
To be able to read the current value of DFLLnCONF or DFLLnRATIO in closed-loop mode, this bit should be written to one. The
updated value is available in DFLLnCONF and DFLLnRATIO when PCLKSR.DFLLnRDY is set.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - SYNC
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14.6.16 BOD Control Register
Name: BOD
Access Type: Read/Write
Reset Value: -
• SFV: Store Final Value
0: The register is read/write
1: The register is read-only, to protect against further accidental writes.
This bit is cleared after any reset except for a BOD reset, and during flash calibration.
• FCD: Fuse Calibration Done
0: The flash calibration will be redone after any reset.
1: The flash calibration will be redone after any reset except for a BOD reset.
This bit is cleared after any reset, except for a BOD reset.
This bit is set when the CTRL, HYST and LEVEL fields have been updated by the flash fuses after a reset.
• CTRL: BOD Control
• HYST: BOD Hysteresis
0: No hysteresis.
1: Hysteresis on.
• LEVEL: BOD Level
This field sets the triggering threshold of the BOD. See Electrical Characteristics for actual voltage levels.
Note that any change to the LEVEL field of the BOD register should be done with the BOD deactivated to avoid spurious reset
or interrupt.
31 30 29 28 27 26 25 24
SFV - - - - - - -
23 22 21 20 19 18 17 16
- - - - - - - FCD
15 14 13 12 11 10 9 8
- - - - - - CTRL
76543210
- HYST LEVEL
Table 14-5. Operation Mode for BOD
CTRL Description
0 BOD is disabled.
1 BOD is enabled and can reset the device. An interrupt request will be generated, if enabled in the IMR
register.
2 BOD is enabled but cannot reset the device. An interrupt request will be generated, if enabled in the IMR
register.
3 Reserved.
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Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
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14.6.17 Voltage Regulator Calibration Register
Name: VREGCR
Access Type: Read/Write
Reset Value: -
• SFV: Store Final Value
0: The register is read/write.
1: The register is read-only, to protect against further accidental writes.
This bit is cleared by a Power-on Reset.
• INTPD: Internal Pull-down
This bit is used for test purposes only.
0: The voltage regulator output is not pulled to ground.
1: The voltage regulator output has a pull-down to ground.
• POR18VALUE: Power-on Reset 1.8V Output Value
0: VDDCORE voltage is below the POR18 power-on threshold level.
1: VDDCORE voltage is above the POR18 power-on threshold level.
This bit is read-only. Writing to this bit has no effect.
• POR33VALUE: Power-on Reset 3.3V Output Value
0: Internal regulator supply voltage is below the POR33 power-on threshold level.
1: Internal regulator supply voltage is above the POR33 power-on threshold level.
This bit is read-only. Writing to this bit has no effect.
• POR18MASK: Power-on Reset 1.8V Output Mask
0: Power-on Reset is not masked.
1: Power-on Reset is masked.
• POR18STATUS: Power-on Reset 1.8V Status
0: Power-on Reset is disabled.
1: Power-on Reset is enabled.
This bit is read-only. Writing to this bit has no effect.
• POR18EN: Power-on Reset 1.8V Enable
Writing a zero to this bit disables the POR18 detector.
Writing a one to this bit enables the POR18 detector.
• POR33MASK: Power-on Reset 3.3V Output Mask
0: Power-on Reset 3.3V is not masked.
31 30 29 28 27 26 25 24
SFV INTPD - - - DBG- POR18VALUE POR33VALUE
23 22 21 20 19 18 17 16
POR18MASK POR18STAT
US POR18EN POR33MASK POR33STAT
US POR33EN DEEPDIS FCD
15 14 13 12 11 10 9 8
- - - - CALIB
76543210
ON VREGOK EN - - SELVDD
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1: Power-on Reset 3.3V is masked.
• POR33STATUS: Power-on Reset 3.3V Status
0: Power-on Reset is disabled.
1: Power-on Reset is enabled.
This bit is read-only. Writing to this bit has no effect.
• POR33EN: Power-on Reset 3.3V Enable
0: Writing a zero to this bit disables the POR33 detector.
1: Writing a one to this bit enables the POR33 detector.
• DEEPDIS: Disable Regulator Deep Mode
0: Regulator will enter deep mode in low-power sleep modes for lower power consumption.
1: Regulator will stay in full-power mode in all sleep modes for shorter start-up time.
• FCD: Flash Calibration Done
0: The flash calibration will be redone after any reset.
1: The flash calibration will only be redone after a Power-on Reset.
This bit is cleared after a Power-on Reset.
This bit is set when the CALIB field has been updated by flash calibration after a reset.
• CALIB: Calibration Value
Calibration value for Voltage Regulator. This is calibrated during production and should not be changed.
• ON: Voltage Regulator On Status
0: The voltage regulator is currently disabled.
1: The voltage regulator is currently enabled.
This bit is read-only. Writing to this bit has no effect.
• VREGOK: Voltage Regulator OK Status
0: The voltage regulator is disabled or has not yet reached a stable output voltage.
1: The voltage regulator has reached the output voltage threshold level after being enabled.
This bit is read-only. Writing to this bit has no effect.
• EN: Enable
0: The voltage regulator is disabled.
1: The voltage regulator is enabled.
Note: This bit is set after a Power-on Reset (POR).
• SELVDD: Select VDD
Output voltage of the Voltage Regulator. The default value of this bit corresponds to an output voltage of 1.8V.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
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14.6.18 System RC Oscillator Calibration Register
Name: RCCR
Access Type: Read/Write
Reset Value: -
• FCD: Flash Calibration Done
0: The flash calibration will be redone after any reset.
1: The flash calibration will only be redone after a Power-on Reset.
This bit is cleared after a POR.
This bit is set when the CALIB field has been updated by the flash fuses after a reset.
• CALIB: Calibration Value
Calibration Value for the System RC oscillator (RCSYS).
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - FCD
15 14 13 12 11 10 9 8
- - - - - - CALIB[9:8]
76543210
CALIB[7:0]
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14.6.19 Supply Monitor 33 Calibration Register
Name: SM33
Access Type: Read/Write
Reset Value: -
• SAMPFREQ: Sampling Frequency
Selects the sampling mode frequency of the 3.3V supply monitor. In sampling mode, the SM33 performs a measurement every
2(SAMPFREQ+5) cycles of the internal 32kHz RC oscillator.
• ONSM: Supply Monitor On Indicator
0: The supply monitor is disabled.
1: The supply monitor is enabled.
This bit is read-only. Writing to this bit has no effect.
• SFV: Store Final Value
0: The register is read/write
1: The register is read-only, to protect against further accidental writes.
This bit is cleared after a reset.
• FCD: Flash Calibration Done
This bit is cleared after a reset.
This bit is set when CALIB field has been updated after a reset.
• CALIB: Calibration Value
Calibration Value for the SM33.
• FS: Force Sampling Mode
0: Sampling mode is enabled in DeepStop and Static mode only.
1: Sampling mode is always enabled.
• CTRL: Supply Monitor Control
31 30 29 28 27 26 25 24
- - - - SAMPFREQ
23 22 21 20 19 18 17 16
- - - - - ONSM SFV FCD
15 14 13 12 11 10 9 8
- - - - CALIB
76543210
FS - - - CTRL
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Selects the operating mode for the SM33.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
Table 14-6. Operation Mode for SM33
CTRL Description
0 SM33 is disabled.
1 SM33 is enabled and can reset the device. An interrupt request will be generated if the corresponding
interrupt is enabled in the IMR register.
2 SM33 is enabled and cannot reset the device. An interrupt request will be generated if the corresponding
interrupt is enabled in the IMR register.
3 SM33 is disabled
4-7 Reserved
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14.6.20 Temperature Sensor Configuration Register
Name: TSENS
Access Type: Read/Write
Reset Value: 0x00000000
• EN: Temperature Sensor Enable
0: The Temperature Sensor is disabled.
1: The Temperature Sensor is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - EN
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14.6.21 120MHz RC Oscillator Configuration Register
Name: RC120MCR
Access Type: Read/Write
Reset Value: 0x00000000
• EN: RC120M Enable
0: The 120 MHz RC oscillator is disabled.
1: The 120 MHz RC oscillator is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - EN
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14.6.22 Backup Register n
Name: BRn
Access Type: Read/Write
Reset Value: 0x00000000
This is a set of general-purpose read/write registers. Data stored in these registers is retained when the device is in Shutdown.
Before writing to these registers the user must ensure that PCLKSR.BRIFARDY is not set.
Note that this registers are protected by a lock. To write to these registers the UNLOCK register has to be written first.
Please refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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14.6.23 32kHz RC Oscillator Configuration Register
Name: RC32KCR
Access Type: Read/Write
Reset Value: 0x00000000
• EN: RC32K Enable
0: The 32 kHz RC oscillator is disabled.
1: The 32 kHz RC oscillator is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Please
refer to the UNLOCK register description for details.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - EN
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14.6.24 Generic Clock Control
Name: GCCTRL
Access Type: Read/Write
Reset Value: 0x00000000
There is one GCCTRL register per generic clock in the design.
• DIV: Division Factor
The number of DIV bits for each generic clock is as shown in the “Generic Clock number of DIV bits” table in the SCIF Module
Configuration section.
• OSCSEL: Oscillator Select
Selects the source clock for the generic clock. Please refer to the “Generic Clock Sources” table in the SCIF Module
Configuration section.
• DIVEN: Divide Enable
0: The generic clock equals the undivided source clock.
1: The generic clock equals the source clock divided by 2*(DIV+1).
• CEN: Clock Enable
0: The generic clock is disabled.
1: The generic clock is enabled.
31 30 29 28 27 26 25 24
DIV[15:8]
23 22 21 20 19 18 17 16
DIV[7:0]
15 14 13 12 11 10 9 8
- - - OSCSEL[4:0]
76543210
- - - - - - DIVEN CEN
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14.6.25 PLL Control Register
Name: PLLn
Access Type: Read/Write
Reset Value: 0x00000000
• PLLCOUNT: PLL Count
Specifies the number of RCSYS clock cycles before ISR.PLLLOCKn will be set after PLLn has been written, or after PLLn has
been automatically re-enabled after exiting a sleep mode.
• PLLMUL: PLL Multiply Factor
• PLLDIV: PLL Division Factor
These fields determine the ratio of the PLL output frequency to the source oscillator frequency:
fvco = (PLLMUL+1)/PLLDIV • fREF if PLLDIV >0
fvco = 2•(PLLMUL+1) • fREF if PLLDIV = 0
Note that the PLLMUL field should always be greater than 1 or the behavior of the PLL will be undefined.
• PLLOPT: PLL Option
PLLOPT[0]: Selects the VCO frequency range (fvco).
0: 80MHz1
1
1
0
0
BaudRate SelectedClock
8 2 – OVER CD = -----------------------------------------------
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The baud rate is calculated with the following formula (OVER=0):
The baud rate error is calculated with the following formula. It is not recommended to work with
an error higher than 5%.
20.6.1.3 Fractional Baud Rate in Asynchronous Mode
The baud rate generator has a limitation: the source frequency is always a multiple of the baud
rate. An approach to this problem is to integrate a high resolution fractional N clock generator,
outputting fractional multiples of the reference source clock. This fractional part is selected with
the Fractional Part field (BRGR.FP), and is activated by giving it a non-zero value. The resolution
is one eighth of CD. The resulting baud rate is calculated using the following formula:
The modified architecture is presented below:
Table 20-3. Baud Rate Example (OVER=0)
Source Clock (Hz)
Expected Baud
Rate (bit/s) Calculation Result CD Actual Baud Rate (bit/s) Error
3 686 400 38 400 6.00 6 38 400.00 0.00%
4 915 200 38 400 8.00 8 38 400.00 0.00%
5 000 000 38 400 8.14 8 39 062.50 1.70%
7 372 800 38 400 12.00 12 38 400.00 0.00%
8 000 000 38 400 13.02 13 38 461.54 0.16%
12 000 000 38 400 19.53 20 37 500.00 2.40%
12 288 000 38 400 20.00 20 38 400.00 0.00%
14 318 180 38 400 23.30 23 38 908.10 1.31%
14 745 600 38 400 24.00 24 38 400.00 0.00%
18 432 000 38 400 30.00 30 38 400.00 0.00%
24 000 000 38 400 39.06 39 38 461.54 0.16%
24 576 000 38 400 40.00 40 38 400.00 0.00%
25 000 000 38 400 40.69 40 38 109.76 0.76%
32 000 000 38 400 52.08 52 38 461.54 0.16%
32 768 000 38 400 53.33 53 38 641.51 0.63%
33 000 000 38 400 53.71 54 38 194.44 0.54%
40 000 000 38 400 65.10 65 38 461.54 0.16%
50 000 000 38 400 81.38 81 38 580.25 0.47%
60 000 000 38 400 97.66 98 38 265.31 0.35%
BaudRate CLKUSART = CD 16
Error 1 ExpectedBaudRate
ActualBaudRate
-------------------------------------------------- = –
BaudRate SelectedClock
8 2 – OVER CD FP
8
+ -------
= --------------------------------------------------------------------
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Figure 20-3. Fractional Baud Rate Generator
20.6.1.4 Baud Rate in Synchronous and SPI Mode
If the USART is configured to operate in synchronous mode, the selected clock is divided by the
BRGR.CD field. This does not apply when CLK is selected.
When CLK is selected the external frequency must be at least 4.5 times lower than the system
clock, and when either CLK or CLK_USART/DIV are selected, CD must be even to ensure a
50/50 duty cycle. If CLK_USART is selected, the generator ensures this regardless of value.
20.6.2 Receiver and Transmitter Control
After a reset, the transceiver is disabled. The receiver/transmitter is enabled by writing a one to
either the Receiver Enable, or Transmitter Enable bit in the Control Register (CR.RXEN, or
CR.TXEN). They may be enabled together and can be configured both before and after they
have been enabled. The user can reset the USART receiver/transmitter at any time by writing a
one to either the Reset Receiver (CR.RSTRX), or Reset Transmitter (CR.RSTTX) bit. This software
reset clears status bits and resets internal state machines, immediately halting any
communication. The user interface configuration registers will retain their values.
The user can disable the receiver/transmitter by writing a one to either the Receiver Disable, or
Transmitter Disable bit (CR.RXDIS, or CR.TXDIS). If the receiver is disabled during a character
reception, the USART will wait for the current character to be received before disabling. If the
transmitter is disabled during transmission, the USART will wait until both the current character
and the character stored in the Transmitter Holding Register (THR) are transmitted before disabling.
If a timeguard has been implemented it will remain functional during the transaction.
USCLKS CD Modulus
Control
FP
FP
CD
glitch-free
logic
16-bit Counter
OVER
FIDI
SYNC
Sampling
Divider
CLK_USART
CLK_USART/DIV
Reserved CLK
CLK
BaudRate
Clock
Sampling
Clock
SYNC
USCLKS = 3
>1
1
2
3
0
0
1
0
1
1
0
0
BaudRate SelectedClock
CD = -------------------------------------
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20.6.3 Synchronous and Asynchronous Modes
20.6.3.1 Transmitter Operations
The transmitter performs equally in both synchronous and asynchronous operating modes
(MR.SYNC). One start bit, up to 9 data bits, an optional parity bit, and up to two stop bits are
successively shifted out on the TXD pin at each falling edge of the serial clock. The number of
data bits is selected by the Character Length field (MR.CHRL) and the MR.MODE9 bit. Nine bits
are selected by writing a one to MODE9, overriding any value in CHRL. The parity bit configuration
is selected in the MR.PAR field. The Most Significant Bit First bit (MR.MSBF) selects which
data bit to send first. The number of stop bits is selected by the MR.NBSTOP field. The 1.5 stop
bit configuration is only supported in asynchronous mode.
Figure 20-4. Character Transmit
The characters are sent by writing to the Character to be Transmitted field (THR.TXCHR). The
transmitter reports status with the Transmitter Ready (TXRDY) and Transmitter Empty
(TXEMPTY) bits in the Channel Status Register (CSR). TXRDY is set when THR is empty.
TXEMPTY is set when both THR and the transmit shift register are empty (transmission complete).
Both TXRDY and TXEMPTY are cleared when the transmitter is disabled. Writing a
character to THR while TXRDY is zero has no effect and the written character will be lost.
Figure 20-5. Transmitter Status
20.6.3.2 Asynchronous Receiver
If the USART is configured in an asynchronous operating mode (MR.SYNC = 0), the receiver will
oversample the RXD input line by either 8 or 16 times the baud rate clock, as selected by the
Oversampling Mode bit (MR.OVER). If the line is zero for half a bit period (four or eight consecutive
samples, respectively), a start bit will be assumed, and the following 8th or 16th sample will
determine the logical value on the line, in effect resulting in bit values being determined at the
middle of the bit period.
D0 D1 D2 D3 D4 D5 D6 D7
TXD
Start
Bit
Parity
Bit
Stop
Bit
Example: 8-bit, Parity Enabled One Stop
Baud Rate
Clock
D0 D1 D2 D3 D4 D5 D6 D7
TXD
Start
Bit
Parity
Bit
Stop
Bit
Baud Rate
Clock
Start
Bit
Write
THR
D0 D1 D2 D3 D4 D5 D6 D7 Parity
Bit
Stop
Bit
TXRDY
TXEMPTY
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The number of data bits, endianess, parity mode, and stop bits are selected by the same bits
and fields as for the transmitter (MR.CHRL, MODE9, MSBF, PAR, and NBSTOP). The synchronization
mechanism will only consider one stop bit, regardless of the used protocol, and when
the first stop bit has been sampled, the receiver will automatically begin looking for a new start
bit, enabling resynchronization even if there is a protocol miss-match. Figure 20-6 and Figure
20-7 illustrate start bit detection and character reception in asynchronous mode.
Figure 20-6. Asynchronous Start Bit Detection
Figure 20-7. Asynchronous Character Reception
20.6.3.3 Synchronous Receiver
In synchronous mode (SYNC=1), the receiver samples the RXD signal on each rising edge of
the Baud Rate Clock. If a low level is detected, it is considered as a start bit. Configuration bits
and fields are the same as in asynchronous mode.
Sampling
Clock (x16)
RXD
Start
Detection
Sampling
Baud Rate
Clock
RXD
Start
Rejection
Sampling
12345678
12345670 1234
12345678 9 10 11 12 13 14 15 16 D0
Sampling
D0 D1 D2 D3 D4 D5 D6 D7
RXD
Parity
Bit
Stop
Bit
Example: 8-bit, Parity Enabled
Baud Rate
Clock
Start
Detection
16
samples
16
samples
16
samples
16
samples
16
samples
16
samples
16
samples
16
samples
16
samples
16
samples
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Figure 20-8. Synchronous Mode Character Reception
20.6.3.4 Receiver Operations
When a character reception is completed, it is transferred to the Received Character field in the
Receive Holding Register (RHR.RXCHR), and the Receiver Ready bit in the Channel Status
Register (CSR.RXRDY) is set. If RXRDY is already set, RHR will be overwritten and the Overrun
Error bit (CSR.OVRE) is set. Reading RHR will clear RXRDY, and writing a one to the Reset
Status bit in the Control Register (CR.RSTSTA) will clear OVRE.
Figure 20-9. Receiver Status
20.6.3.5 Parity
The USART supports five parity modes selected by MR.PAR. The PAR field also enables the
Multidrop mode, see ”Multidrop Mode” on page 443. If even parity is selected, the parity bit will
be a zero if there is an even number of ones in the data character, and if there is an odd number
it will be a one. For odd parity the reverse applies. If space or mark parity is chosen, the parity bit
will always be a zero or one, respectively. See Table 20-4.
D0 D1 D2 D3 D4 D5 D6 D7
RXD
Start Sampling
Parity Bit
Stop Bit
Example: 8-bit, Parity Enabled 1 Stop
Baud Rate
Clock
D0 D1 D2 D3 D4 D5 D6 D7
RXD
Start
Bit
Parity
Bit
Stop
Bit
Baud Rate
Clock
Write
CR
RXRDY
OVRE
D0 D1 D2 D3 D4 D5 D6 D7 Start
Bit
Parity
Bit
Stop
Bit
RSTSTA = 1
Read
RHR
Table 20-4. Parity Bit Examples
Alphanum
Character Hex Bin
Parity Mode
Odd Even Mark Space None
A 0x41 0100 0001 1 0 1 0 -
V 0x56 0101 0110 1 0 1 0 -
R 0x52 0101 0010 0 1 1 0 -
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The receiver will report parity errors in CSR.PARE, unless parity is disabled. Writing a one to
CR.RSTSTA will clear PARE. See Figure 20-10
Figure 20-10. Parity Error
20.6.3.6 Multidrop Mode
If PAR is either 0x6 or 0x7, the USART runs in Multidrop mode. This mode differentiates data
and address characters. Data has the parity bit zero and addresses have a one. By writing a one
to the Send Address bit (CR.SENDA) the user will cause the next character written to THR to be
transmitted as an address. Receiving a character with a one as parity bit will set PARE.
20.6.3.7 Transmitter Timeguard
The timeguard feature enables the USART to interface slow devices by inserting an idle state on
the TXD line in between two characters. This idle state corresponds to a long stop bit, whose
duration is selected by the Timeguard Value field in the Transmitter Timeguard Register
(TTGR.TG). The transmitter will hold the TXD line high for TG bit periods, in addition to the number
of stop bits. As illustrated in Figure 20-11, the behavior of TXRDY and TXEMPTY is modified
when TG has a non-zero value. If a pending character has been written to THR, the TXRDY bit
will not be set until this characters start bit has been sent. TXEMPTY will remain low until the
timeguard transmission has completed.
Figure 20-11. Timeguard Operation
D0 D1 D2 D3 D4 D5 D6 D7
RXD
Start
Bit
Bad
Parity
Bit
Stop
Bit
Baud Rate
Clock
Write
CR
PARE
RXRDY
RSTSTA = 1
D0 D1 D2 D3 D4 D5 D6 D7
TXD
Start
Bit
Parity
Bit
Stop
Bit
Baud Rate
Clock
Start
Bit
TG = 4
Write
THR
D0 D1 D2 D3 D4 D5 D6 D7 Parity
Bit
Stop
Bit
TXRDY
TXEMPTY
TG = 4
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Table 20-5. Maximum Baud Rate Dependent Timeguard Durations
20.6.3.8 Receiver Time-out
The Time-out Value field in the Receiver Time-out Register (RTOR.TO) enables handling of variable-length
frames by detection of selectable idle durations on the RXD line. The value written to
TO is loaded to a decremental counter, and unless it is zero, a time-out will occur when the
amount of inactive bit periods match the initial counter value. If a time-out has not occurred, the
counter will reload and restart every time a new character arrives. A time-out sets the TIMEOUT
bit in CSR. Clearing TIMEOUT can be done in two ways:
• Writing a one to the Start Time-out bit (CR.STTTO). This also aborts count down until the
next character has been received.
• Writing a one to the Reload and Start Time-out bit (CR.RETTO). This also reloads the
counter and restarts count down immediately.
Figure 20-12. Receiver Time-out Block Diagram
Table 20-6. Maximum Time-out Period
Baud Rate (bit/sec) Bit time (µs) Timeguard (ms)
1 200 833 212.50
9 600 104 26.56
14400 69.4 17.71
19200 52.1 13.28
28800 34.7 8.85
33400 29.9 7.63
56000 17.9 4.55
57600 17.4 4.43
115200 8.7 2.21
Baud Rate (bit/sec) Bit Time (µs) Time-out (ms)
600 1 667 109 225
1 200 833 54 613
2 400 417 27 306
4 800 208 13 653
16-bit Time-out
Counter
0
TO
TIMEOUT
Baud Rate
Clock
=
Character
Received
RETTO
Load
Clock
16-bit
Value
STTTO
1 D Q
Clear
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20.6.3.9 Framing Error
The receiver is capable of detecting framing errors. A framing error has occurred if a stop bit
reads as zero. This can occur if the transmitter and receiver are not synchronized. A framing
error is reported by CSR.FRAME as soon as the error is detected, at the middle of the stop bit.
Figure 20-13. Framing Error Status
20.6.3.10 Transmit Break
When TXRDY is set, the user can request the transmitter to generate a break condition on the
TXD line by writing a one to The Start Break bit (CR.STTBRK). The break is treated as a normal
0x00 character transmission, clearing TXRDY and TXEMPTY, but with zeroes for preambles,
start, parity, stop, and time guard bits. Writing a one to the Stop Break bit (CR.STBRK) will stop
the generation of new break characters, and send ones for TG duration or at least 12 bit periods,
ensuring that the receiver detects end of break, before resuming normal operation. Figure 20-14
illustrates STTBRK and STPBRK effect on the TXD line.
Writing to STTBRK and STPBRK simultaneously can lead to unpredictable results. Writes to
THR before a pending break has started will be ignored.
9 600 104 6 827
14400 69 4 551
19200 52 3 413
28800 35 2 276
33400 30 1 962
56000 18 1 170
57600 17 1 138
200000 5 328
Baud Rate (bit/sec) Bit Time (µs) Time-out (ms)
D0 D1 D2 D3 D4 D5 D6 D7
RXD
Start
Bit
Parity
Bit
Stop
Bit
Baud Rate
Clock
Write
CR
FRAME
RXRDY
RSTSTA = 1
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Figure 20-14. Break Transmission
20.6.3.11 Receive Break
A break condition is assumed when incoming data, parity, and stop bits are zero. This corresponds
to a framing error, but FRAME will remain zero while the Break Received/End Of Break
bit (CSR.RXBRK) is set. Writing a one to CR.RSTSTA will clear RXBRK. An end of break will
also set RXBRK, and is assumed when TX is high for at least 2/16 of a bit period in asynchronous
mode, or when a high level is sampled in synchronous mode.
20.6.3.12 Hardware Handshaking
The USART features an out-of-band hardware handshaking flow control mechanism, implementable
by connecting the RTS and CTS pins with the remote device, as shown in Figure 20-
15.
Figure 20-15. Connection with a Remote Device for Hardware Handshaking
Writing 0x2 to the MR.MODE field configures the USART to operate in this mode. The receiver
will drive its RTS pin high when disabled or when the Reception Buffer Full bit (CSR.RXBUFF) is
set by the Buffer Full signal from the Peripheral DMA controller. If the receivers RTS pin is high,
the transmitters CTS pin will also be high and only the active character transactions will be completed.
Allocating a new buffer to the DMA controller by clearing RXBUFF, will drive the RTS pin
low, allowing the transmitter to resume transmission. Detected level changes on the CTS pin
can trigger interrupts, and are reported by the CTS Input Change bit in the Channel Status Register
(CSR.CTSIC).
Figure 20-16 illustrates receiver functionality, and Figure 20-17 illustrates transmitter
functionality.
D0 D1 D2 D3 D4 D5 D6 D7
TXD
Start
Bit
Parity
Bit
Stop
Bit
Baud Rate
Clock
Write
CR
TXRDY
TXEMPTY
STTBRK = 1 STPBRK = 1
Break Transmission End of Break
USART
TXD
CTS
Remote
Device
RXD
RXD TXD
RTS
RTS
CTS
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Figure 20-16. Receiver Behavior when Operating with Hardware Handshaking
Figure 20-17. Transmitter Behavior when Operating with Hardware Handshaking
Figure 20-18.
20.6.4 SPI Mode
The USART features a Serial Peripheral Interface (SPI) link compliant mode, supporting synchronous,
full-duplex communication, in both master and slave mode. Writing 0xE (master) or
0xF (slave) to MR.MODE will enable this mode. A SPI in master mode controls the data flow to
and from the other SPI devices, who are in slave mode. It is possible to let devices take turns
being masters (aka multi-master protocol), and one master may shift data simultaneously into
several slaves, but only one slave may respond at a time. A slave is selected when its slave
select (NSS) signal has been raised by the master. The USART can only generate one NSS signal,
and it is possible to use standard I/O lines to address more than one slave.
20.6.4.1 Modes of Operation
The SPI system consists of two data lines and two control lines:
• Master Out Slave In (MOSI): This line supplies the data shifted from master to slave. In
master mode this is connected to TXD, and in slave mode to RXD.
• Master In Slave Out (MISO): This line supplies the data shifted from slave to master. In
master mode this is connected to RXD, and in slave mode to TXD.
• Serial Clock (CLK): This is controlled by the master. One period per bit transmission. In both
modes this is connected to CLK.
• Slave Select (NSS): This control line allows the master to select or deselect a slave. In
master mode this is connected to RTS, and in slave mode to CTS.
Changing SPI mode after initial configuration has to be followed by a transceiver software reset
in order to avoid unpredictable behavior.
20.6.4.2 Baud Rate
The baud rate generator operates as described in ”Baud Rate in Synchronous and SPI Mode”
on page 439, with the following requirements:
In SPI Master Mode:
RTS
RXBUFF
Write
CR
RXEN = 1
RXD
RXDIS = 1
CTS
TXD
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• The Clock Selection field (MR.USCLKS) must not equal 0x3 (external clock, CLK).
• The Clock Output Select bit (MR.CLKO) must be one.
• The BRGR.CD field must be at least 0x4.
• If USCLKS is one (internal divided clock, CLK_USART/DIV), the value in CD has to be even,
ensuring a 50:50 duty cycle. CD can be odd if USCLKS is zero (internal clock, CLK_USART).
In SPI Slave Mode:
• CLK frequency must be at least four times lower than the system clock.
20.6.4.3 Data Transfer
• Up to nine data bits are successively shifted out on the TXD pin at each edge. There are no
start, parity, or stop bits, and MSB is always sent first. The SPI Clock Polarity (MR.CPOL),
and SPI Clock Phase (MR.CPHA) bits configure CLK by selecting the edges upon which bits
are shifted and sampled, resulting in four non-interoperable protocol modes see Table 20-7.
A master/slave pair must use the same configuration, and the master must be reconfigured if
it is to communicate with slaves using different configurations. See Figures 20-19 and 20-20.
Figure 20-19. SPI Transfer Format (CPHA=1, 8 bits per transfer)
Table 20-7. SPI Bus Protocol Modes
SPI Bus Protocol Mode CPOL CPHA
0 01
1 00
2 11
3 10
CLK cycle (for reference)
CLK
(CPOL= 1)
MOSI
SPI Master ->TXD
SPI Slave ->RXD
MISO
SPI Master ->RXD
SPI Slave ->TXD
NSS
SPI Master ->RTS
SPI Slave ->CTS
MSB
MSB
1
CLK
(CPOL= 0)
3 5 6 7 8
4 3 2 1 LSB
6
6 5
5 4 3 2 1 LSB
2 4
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Figure 20-20. SPI Transfer Format (CPHA=0, 8 bits per transfer)
20.6.4.4 Receiver and Transmitter Control
See ”Transmitter Operations” on page 440, and ”Receiver Operations” on page 442.
20.6.4.5 Character Transmission and Reception
In SPI master mode, the slave select line (NSS) is asserted low one bit period before the start of
transmission, and released high one bit period after every character transmission. A delay for at
least three bit periods is always inserted in between characters. In order to address slave
devices supporting the Chip Select Active After Transfer (CSAAT) mode, NSS can be forced low
by writing a one to the Force SPI Chip Select bit (CR.RTSEN/FCS). Releasing NSS when FCS
is one, is only possible by writing a one to the Release SPI Chip Select bit (CR.RTSDIS/RCS).
In SPI slave mode, a low level on NSS for at least one bit period will allow the slave to initiate a
transmission or reception. The Underrun Error bit (CSR.UNRE) is set if a character must be sent
while THR is empty, and TXD will be high during character transmission, as if 0xFF was being
sent. If a new character is written to THR it will be sent correctly during the next transmission
slot. Writing a one to CR.RSTSTA will clear UNRE. To ensure correct behavior of the receiver in
SPI slave mode, the master device sending the frame must ensure a minimum delay of one bit
period in between each character transmission.
20.6.4.6 Receiver Time-out
Receiver Time-out’s are not possible in SPI mode as the baud rate clock is only active during
data transfers.
20.6.5 LIN Mode
The USART features a LIN (Local Interconnect Network) 1.3 and 2.0 compliant mode, embedding
full error checking and reporting, automatic frame processing with up to 256 data bytes,
CLK cycle (for reference)
CLK
(CPOL= 0)
CLK
(CPOL= 1)
MOSI
SPI Master -> TXD
SPI Slave -> RXD
MISO
SPI Master -> RXD
SPI Slave -> TXD
NSS
SPI Master -> RTS
SPI Slave -> CTS
MSB 6 5
MSB 6 5
4
4 3
3 2
2 1
1 LSB
LSB
1 2 3 4 5 6 7 8
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customizable response data lengths, and requires minimal CPU resources. Writing 0xA (master)
or 0xB (slave) to MR.MODE enables this mode.
20.6.5.1 Modes of operation
Changing LIN mode after initial configuration has to be followed by a transceiver software reset
in order to avoid unpredictable behavior.
20.6.5.2 Receiver and Transmitter Control
See Section “20.6.2” on page 439.
20.6.5.3 Baud Rate Configuration
The LIN nodes baud rate is configured in the Baud Rate Generator Register (BRGR), See Section
“20.6.1.1” on page 437.
20.6.5.4 Character Transmission and Reception
See ”Transmitter Operations” on page 440, and ”Receiver Operations” on page 442.
20.6.5.5 Header Transmission (Master Node Configuration)
All LIN frames start with a header sent by the master. As soon as the identifier has been written
to the Identifier Character field in the LIN Identifier Register (LINIR.IDCHR), TXRDY is cleared
and the header is sent. The header consists of a Break, Sync, and Identifier field. TXRDY is set
when the identifier has been transferred into the transmitters shift register.
The Break field consists of 13 dominant bits, the break, and one recessive bit, the break delimiter.
The Sync field is the character 0x55. The Identifier field contains the Identifier as written to
IDCHR. The identifier parity bits can be generated automatically (see Section 20.6.5.8).
Figure 20-21. Header Transmission
20.6.5.6 Header Reception (Slave Node Configuration)
The USART stays idle until it detects a break field, consisting of at least 11 consecutive dominant
bits (zeroes) on the bus. A received break will set the Lin Break bit (CSR.LINBK). The Sync
field is used to synchronize the baud rate (see Section 20.6.5.7). IDCHR is updated and the LIN
Identifier bit (CSR.LINID) is set when the Identifier has been received. The Identifier parity bits
can be automatically checked (see Section 20.6.5.8). Writing a one to RSTSTA will clear LINBK
and LINID.
TXD
Baud Rate
Clock
Start
Bit
Write
LINIR
10101010
TXRDY
Stop
Bit
Start
Bit Break Field ID0 ID1 ID2 ID3 ID4 ID5 ID6 ID7
13 dominant bits (at 0)
Stop
Bit
Break
Delimiter
1 recessive bit
(at 1)
Synch Byte = 0x55
LINIR ID
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Figure 20-22. Header Reception
20.6.5.7 Slave Node Synchronization
Synchronization is only done by the slave. If the Sync field is not 0x55, an Inconsistent Sync
Field error (CSR.LINISFE) is generated. The time between falling edges is measured by a 19-bit
counter, driven by the sampling clock (see Section 20.6.1).
Figure 20-23. Sync Field
The counter starts when the Sync field start bit is detected, and continues for eight bit periods.
The 16 most significant bits (counter value divided by 8) becomes the new clock divider
(BRGR.CD), and the three least significant bits (the remainder) becomes the new fractional part
(BRGR.FP).
Figure 20-24. Slave Node Synchronization
The synchronization accuracy depends on:
• The theoretical slave node clock frequency; nominal clock frequency (FNom)
• The baud rate
Break Field
13 dominant bits (at 0)
Break
Delimiter
1 recessive bit
(at 1)
Start
Bit 10101010 Stop
Bit
Start
Bit ID0 ID1 ID2 ID4 ID3 ID6 ID5 ID7 Stop
Bit
Synch Byte = 0x55
Baud Rate
Clock
RXD
Write US_CR
With RSTSTA=1
US_LINIR
LINID
Start
bit
Stop
bit
Synch Field
8 Tbit
2 Tbit 2 Tbit 2 Tbit 2 Tbit
RXD
Baud Rate
Clock
LINIDRX
Synchro Counter 000_0011_0001_0110_1101
BRGR
Clcok Divider (CD)
0000_0110_0010_1101
BRGR
Fractional Part (FP)
101
Initial CD
Initial FP
Reset
Start
Bit 10101010 Stop
Bit
Start
Bit Break Field ID0 ID1 ID2 ID3 ID4 ID5 ID6 ID7
13 dominant bits (at 0)
Stop
Bit
Break
Delimiter
1 recessive bit
(at 1)
Synch Byte = 0x55
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• The oversampling mode (OVER=0 => 16x, or OVER=1 => 8x)
The following formula is used to calculate synchronization deviation, where FSLAVE is the real
slave node clock frequency, and FTOL_UNSYNC is the difference between FNom and FSLAVE According
to the LIN specification, FTOL_UNSYNCH may not exceed ±15%, and the bit rates between two
nodes must be within ±2% of each other, resulting in a maximal BaudRate_deviation of ±1%.
Minimum nominal clock frequency with a fractional part:
Examples:
• Baud rate = 20 kbit/s, OVER=0 (Oversampling 16x) => FNom(min) = 2.64 MHz
• Baud rate = 20 kbit/s, OVER=1 (Oversampling 8x) => FNom(min) = 1.47 MHz
• Baud rate = 1 kbit/s, OVER=0 (Oversampling 16x) => FNom(min) = 132 kHz
• Baud rate = 1 kbit/s, OVER=1 (Oversampling 8x) => FNom(min) = 74 kHz
If the fractional part is not used, the synchronization accuracy is much lower. The 16 most significant
bits, added with the first least significant bit, becomes the new clock divider (CD). The
equation of the baud rate deviation is the same as above, but the constants are:
Minimum nominal clock frequency without a fractional part:
Examples:
• Baud rate = 20 kbit/s, OVER=0 (Oversampling 16x) => FNom(min) = 19.12 MHz
• Baud rate = 20 kbit/s, OVER=1 (Oversampling 8x) => FNom(min) = 9.71 MHz
• Baud rate = 1 kbit/s, OVER=0 (Oversampling 16x) => FNom(min) = 956 kHz
• Baud rate = 1 kbit/s, OVER=1 (Oversampling 8x) => FNom(min) = 485 kHz
20.6.5.8 Identifier Parity
An identifier field consists of two sub-fields; the identifier and its parity. Bits 0 to 5 are assigned
to the identifier, while bits 6 and 7 are assigned to parity. Automatic parity management is disabled
by writing a one to the Parity Disable bit in the LIN Mode register (LINMR.PARDIS).
BaudRate_deviation 100 8 2 OVER – + BaudRate
8 FSLAVE -------------------------------------------------------------------------------------------------- = %
BaudRate_deviation 100 8 2 OVER – + BaudRate
8
FTOL_UNSYNC
100 ----------------------------------- xFNom
--------------------------------------------------------------------------------------------------
= %
–0.5 +0.5 -1 +1
FNom min 100 0.5 8 2 OVER – + 1 BaudRate
8 –15
100
--------- + 1 1%
------------------------------------------------------------------------------------------------------
= Hz
–4 +4 -1 +1
FNom min 100 4 8 2 OVER – + 1 Baudrate
8 –15
100
--------- + 1 1%
-----------------------------------------------------------------------------------------------
= Hz
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• PARDIS=0: During header transmission, the parity bits are computed and in the shift register
they replace bits six and seven from IDCHR. During header reception, the parity bits are
checked and can generate a LIN Identifier Parity Error (see Section 20.6.6). Bits six and
seven in IDCHR read as zero when receiving.
• PARDIS=1: During header transmission, all the bits in IDCHR are sent on the bus. During
header reception, all the bits in IDCHR are updated with the received Identifier.
20.6.5.9 Node Action
After an identifier transaction, a LIN response mode has to be selected. This is done in the Node
Action field (LINMR.NACT). Below are some response modes exemplified in a small LIN cluster:
• Response, from master to slave1:
Master: NACT=PUBLISH
Slave1: NACT=SUBSCRIBE
Slave2: NACT=IGNORE
• Response, from slave1 to master:
Master: NACT=SUBSCRIBE
Slave1: NACT=PUBLISH
Slave2: NACT=IGNORE
• Response, from slave1 to slave2:
Master: NACT=IGNORE
Slave1: NACT=PUBLISH
Slave2: NACT=SUBSCRIBE
20.6.5.10 LIN Response Data Length
The response data length is the number of data fields (bytes), excluding the checksum.
Figure 20-25. Response Data Length
The response data length can be configured, either by the user, or automatically by bits 4 and 5
in the Identifier (IDCHR), in accordance to LIN 1.1. The user selects mode by writing to the Data
Length Mode bit (LINMR.DML):
• DLM=0: the response data length is configured by the user by writing to the 8-bit Data Length
Control field (LINMR.DLC). The response data length equals DLC + 1 bytes.
User configuration: 1 - 256 data fields (DLC+1)
Identifier configuration: 2/4/8 data fields
Sync
Break
Sync
Field
Identifier
Field
Checksum
Field
Data
Field
Data
Field
Data
Field
Data
Field
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• DLM=1: the response data length is defined by the Identifier bits according to the table below.
20.6.5.11 Checksum
The last frame field is the checksum. It is configured by the Checksum Type (LINMR.CHKTYP),
and the Checksum Disable (LINMR.CHKDIS) bits. TXRDY will not be set after the last THR data
write if enabled. Writing a one to CHKDIS will disable the automatic checksum generation/checking,
and the user may send/check this last byte manually, disguised as a normal data.
The checksum is an inverted 8-bit sum with carry, either:
• over all data bytes, called a classic checksum. This is used for LIN 1.3 compliant slaves, and
automatically managed when CHKDIS=0, and CHKTYP=1.
• over all data bytes and the protected identifier, called an enhanced checksum. This is used
for LIN 2.0 compliant slaves, and automatically managed when CHKDIS=0, and CHKTYP=0.
20.6.5.12 Frame Slot Mode
A LIN master can be configured to use frame slots with a pre-defined minimum length. Writing a
one to the Frame Slot Mode Disable bit (LINMR.FSDIS) disables this mode. This mode will not
allow TXRDY to be set after a frame transfer until the entire frame slot duration has elapsed, in
effect preventing the master from sending a new header. The LIN Transfer Complete bit
(CSR.LINTC) will still be set after the checksum has been sent. Writing a one to CR.RSTST
clears LINTC.
Figure 20-26. Frame Slot Mode with Automatic Checksum
The minimum frame slot size is determined by TFrame_Maximum, and calculated below (all values
in bit periods):
• THeader_Nominal = 34
Table 20-8. Response Data Length if DLM = 1
IDCHR[5] IDCHR[4] Response Data Length [bytes]
00 2
01 2
10 4
11 8
Break Synch Protected
Identifier
Data N Checksum
Header
Interframe
space Response
space
Frame
Frame slot = TFrame_Maximum
Response
TXRDY
Write
THR
Write
LINID
Data 1 Data 2 Data 3
Data3
Data N-1
Data N
Frame Slot Mode
Disabled
Frame Slot Mode
Enabled
LINTC
Data 1
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• TFrame_Maximum = 1.4 x (THeader_Nominal + TResponse_Nominal + 1)(Note:)
Note: The term “+1” leads to an integer result for TFrame_Max (LIN Specification 1.3)
If the Checksum is sent (CHKDIS=0):
• TResponse_Nominal = 10 x (NData + 1)
• TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1 + 1) + 1)
• TFrame_Maximum = 77 + 14 x DLC
If the Checksum is not sent (CHKDIS=1):
• TResponse_Nominal = 10 x NData
• TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1) + 1)
• TFrame_Maximum = 63 + 14 x DLC
20.6.6 LIN Errors
These error bits are cleared by writing a one to CSR.RSTSTA.
20.6.6.1 Slave Not Responding Error (CSR.LINSNRE)
This error is generated if no valid message appears within the TFrame_Maximum time frame
slot, while the USART is expecting a response from another node (NACT=SUBSCRIBE).
20.6.6.2 Checksum Error (CSR.LINCE)
This error is generated if the received checksum is wrong. This error can only be generated if the
checksum feature is enabled (CHKDIS=0).
20.6.6.3 Identifier Parity Error (CSR.LINIPE)
This error is generated if the identifier parity is wrong. This error can only be generated if parity is
enabled (PARDIS=0).
20.6.6.4 Inconsistent Sync Field Error (CSR.LINISFE)
This error is generated in slave mode if the Sync Field character received is not 0x55. Synchronization
procedure is aborted.
20.6.6.5 Bit Error (CSR.LINBE)
This error is generated if the value transmitted by the USART on Tx differs from the value sampled
on Rx. If a bit error is detected, the transmission is aborted at the next byte border.
20.6.7 LIN Frame Handling
20.6.7.1 Master Node Configuration
• Write a one to CR.TXEN and CR.RXEN to enable both transmitter and receiver
• Select LIN mode and master node by writing to MR.MODE
• Configure the baud rate by writing to CD and FP in BRGR
• Configure the frame transfer by writing to NACT, PARDIS, CHKDIS, CHKTYPE, DLCM,
FSDIS, and DLC in LINMR
• Check that CSR.TXRDY is one
• Send the header by writing to LINIR.IDCHR
The following procedure depends on the NACT setting:
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• Case 1: NACT=PUBLISH, the USART sends a response
– Wait until TXRDY is a one
– Send a byte by writing to THR.TXCHR
– Repeat the two previous steps until there is no more data to send
– Wait until CSR.LINTC is a one
– Check for LIN errors
• Case 2: NACT=SUBSCRIBE, the USART receives a response
– Wait until RXRDY is a one
– Read RHR.RXCHR
– Repeat the two previous steps until there is no more data to read
– Wait until LINTC is a one
– Check for LIN errors
• Case 3: NACT=IGNORE, the USART is not concerned by a response
– Wait until LINTC is a one
– Check for LIN errors
Figure 20-27. Master Node Configuration, NACT=PUBLISH
Frame
Break Synch Protected
Identifier
Data 1 Data N Checksum
TXRDY
Write
THR
Write
LINIR
Data 1 Data 2 Data 3
Data N-1
Data N
RXRDY
Header
Interframe
space Response
space
Frame slot = TFrame_Maximum
Data3 Response
LINTC
FSDIS=1 FSDIS=0
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Figure 20-28. Master Node Configuration, NACT=SUBSCRIBE
Figure 20-29. Master Node Configuration, NACT=IGNORE
20.6.7.2 Slave Node Configuration
This is identical to the master node configuration above, except for:
• LIN mode selected in MR.MODE is slave
• When the baud rate is configured, wait until CSR.LINID is a one, then;
• Check for LINISFE and LINPE errors, clear errors and LINIDby writing a one to RSTSTA
• Read IDCHR
• Configure the frame transfer by writing to NACT, PARDIS, CHKDIS, CHKTYPE, DLCM, and
DLC in LINMR
IMPORTANT: if NACT=PUBLISH, and this field is already correct, the LINMR register must still
be written with this value in order to set TXRDY, and to request the corresponding Peripheral
DMA Controller write transfer.
The different NACT settings result in the same procedure as for the master node, see page 455.
Break Synch Protected
Identifier
Data 1 Data N Checksum
TXRDY
Read
RHR
Write
LINIR
Data 1
Data N-1
Data N-1
RXRDY
Data N-2 Data N
Header
Interframe
Response space
space
Frame
Frame slot = TFrame_Maximum
Data3 Response
LINTC
FSDIS=1 FSDIS=0
TXRDY
Write
LINIR
RXRDY
LINTC
Break Synch Protected
Identifier
Data 1 Data N-1 Data N Checksum
Header
Interframe
Response space
space
Frame
Frame slot = TFrame_Maximum
Data3 Response
FSDIS=1 FSDIS=0
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Figure 20-30. Slave Node Configuration, NACT=PUBLISH
Figure 20-31. Slave Node Configuration, NACT=SUBSCRIBE
Figure 20-32. Slave Node Configuration, NACT=IGNORE
20.6.8 LIN Frame Handling With The Peripheral DMA Controller
The USART can be used together with the Peripheral DMA Controller in order to transfer data
without processor intervention. The DMA Controller uses the TXRDY and RXRDY bits, to trigger
one byte writes or reads. It always writes to THR, and it always reads RHR.
Break Synch Protected
Identifier
Data 1 Data N Checksum
TXRDY
Write
THR
Read
LINID
Data 1 Data 3
Data N-1
Data N
RXRDY
LINIDRX
Data 2
LINTC
TXRDY
Read
RHR
Read
LINID
RXRDY
LINIDRX
LINTC
Break Synch Protected
Identifier
Data 1 Data N Checksum
Data 1
Data N-1
Data N-2 Data N-1 Data N
TXRDY
Read
RHR
Read
LINID
RXRDY
LINIDRX
LINTC
Break Synch Protected
Identifier
Data 1 Data N Checksum Data N-1
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20.6.8.1 Master Node Configuration
The Peripheral DMA Controller Mode bit (LINMR.PDCM) allows the user to select configuration:
• PDCM=0: LIN configuration must be written to LINMR, it is not stored in the write buffer.
• PDCM=1: LIN configuration is written by the DMA Controller to THR, and is stored in the
write buffer. Since data transfer size is a byte, the transfer is split into two accesses. The first
writes the NACT, PARDIS, CHKDIS, CHKTYP, DLM and FSDIS bits, while the second writes
the DLC field. If NACT=PUBLISH, the write buffer will also contain the Identifier.
When NACT=SUBSCRIBE, the read buffer contains the data.
Figure 20-33. Master Node with Peripheral DMA Controller (PDCM=0)
Figure 20-34. Master Node with Peripheral DMA Controller (PDCM=1)
|
|
|
|
RXRDY
TXRDY
Peripheral
bus
USART LIN
CONTROLLER
DATA 0
DATA N
|
|
|
|
READ BUFFER
NODE ACTION = PUBLISH NODE ACTION = SUBSCRIBE
Peripheral DMA
Controller
RXRDY
Peripheral
bus
DATA 0
DATA 1
DATA N
WRITE BUFFER
Peripheral DMA
Controller
USART LIN
CONTROLLER
|
|
|
|
|
|
|
|
NACT
PARDIS
CHKDIS
CHKTYP DLM
FSDIS
DLC
IDENTIFIER
DATA 0
DATA N
WRITE BUFFER
RXRDY
Peripheral
bus
DLC
IDENTIFIER
DATA 0
DATA N
WRITE BUFFER
RXRDY READ BUFFER
NODE ACTION = PUBLISH NODE ACTION = SUBSCRIBE
Peripheral DMA
Controller
Peripheral DMA
Controller
USART LIN
CONTROLLER
NACT
PARDIS
CHKDIS
CHKTYP DLM
FSDIS
USART LIN
CONTROLLER
TXRDY
Peripheral
bus
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20.6.8.2 Slave Node Configuration
In this mode, the Peripheral DMA Controller transfers only data. The user reads the Identifier
from LINIR, and selects LIN mode by writing to LINMR. When NACT=PUBLISH the data is in the
write buffer, while the read buffer contains the data when NACT=SUBSCRIBE.
IMPORTANT: if in slave mode, NACT is already configured correctly as PUBLISH, the LINMR
register must still be written with this value in order to set TXRDY, and to request the corresponding
Peripheral DMA Controller write transfer.
Figure 20-35. Slave Node with Peripheral DMA Controller
20.6.9 Wake-up Request
Any node in a sleeping LIN cluster may request a wake-up. By writing to the Wakeup Signal
Type bit (LINMR.WKUPTYP), the user can choose to send either a LIN 1.3 (WKUPTYP=1), or a
LIN 2.0 (WKUPTYP=0) compliant wakeup request. Writing a one to the Send LIN Wakeup Signal
bit (CR.LINWKUP), transmits a wakeup, and when completed sets LINTC.
According to LIN 1.3, the wakeup request should be generated with the character 0x80 in order
to impose eight successive dominant bits.
According to LIN 2.0, the wakeup request is issued by forcing the bus into the dominant state for
250µs to 5ms. Sending the character 0xF0 does this, regardless of baud rate.
• Baud rate max = 20 kbit/s -> one bit period = 50µs -> five bit periods = 250µs
• Baud rate min = 1 kbit/s -> one bit period = 1ms -> five bit periods = 5ms
20.6.10 Bus Idle Time-out
LIN bus inactivity should eventually cause slaves to time-out and enter sleep mode. LIN 1.3
specifies this to 25000 bit periods, whilst LIN 2.0 specifies 4seconds. For the time-out counter
operation see Section 20.6.3.8 ”Receiver Time-out” on page 444.
|
|
|
|
|
|
|
|
DATA 0
DATA N
RXRDY
Peripheral
Bus
READ BUFFER
NACT = SUBSCRIBE DATA 0
DATA N
TXRDY
Peripheral
bus
WRITE BUFFER
USART LIN
CONTROLLER
USART LIN
CONTROLLER
Peripheral DMA
Controller
Peripheral DMA
Controller
Table 20-9. Receiver Time-out Values (RTOR.TO)
LIN Specification Baud Rate Time-out period TO
2.0
1 000 bit/s
4s
4 000
2 400 bit/s 9 600
9 600 bit/s 38 400
19 200 bit/s 76 800
20 000 bit/s 80 000
1.3 - 25 000 bit periods 25 000
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20.6.11 Test Modes
The internal loopback feature enables on-board diagnostics, and allows the USART to operate
in three different test modes, with reconfigured pin functionality, as shown below.
20.6.11.1 Normal Mode
During normal operation, a receivers RXD pin is connected to a transmitters TXD pin.
Figure 20-36. Normal Mode Configuration
20.6.11.2 Automatic Echo Mode
Automatic echo mode allows bit-by-bit retransmission. When a bit is received on the RXD pin, it
is also sent to the TXD pin, as shown in Figure 20-37. Transmitter configuration has no effect.
Figure 20-37. Automatic Echo Mode Configuration
20.6.11.3 Local Loopback Mode
Local loopback mode connects the output of the transmitter directly to the input of the receiver,
as shown in Figure 20-38. The TXD and RXD pins are not used. The RXD pin has no effect on
the receiver and the TXD pin is continuously driven high, as in idle state.
Figure 20-38. Local Loopback Mode Configuration
20.6.11.4 Remote Loopback Mode
Remote loopback mode connects the RXD pin to the TXD pin, as shown in Figure 20-39. The
transmitter and the receiver are disabled and have no effect. This mode allows bit-by-bit
retransmission.
Receiver
Transmitter
RXD
TXD
Receiver
Transmitter
RXD
TXD
Receiver
Transmitter
RXD
TXD
1
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Figure 20-39. Remote Loopback Mode Configuration
20.6.12 Write Protection Registers
To prevent single software errors from corrupting USART behavior, certain address spaces can
be write-protected by writing the correct Write Protect KEY and a one to the Write Protect
Enable bit in the Write Protect Mode Register (WPMR.WPKEY, and WPMR.WPEN). Disabling
the write protection is done by writing the correct key, and a zero to WPEN.
Write attempts to a write protected register are detected and the Write Protect Violation Status
bit in the Write Protect Status Register (WPSR.WPVS) is set, while the Write Protect Violation
Source field (WPSR.WPVSRC) indicates the targeted register. Writing the correct key to the
Write Protect KEY bit (WPMR.WPKEY) clears WPVSRC and WPVS.
The protected registers are:
• ”Mode Register” on page 466
• ”Baud Rate Generator Register” on page 476
• ”Receiver Time-out Register” on page 477
• ”Transmitter Timeguard Register” on page 478
Receiver
Transmitter
RXD
TXD
1
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20.7 User Interface
Note: 1. Values in the Version Register vary with the version of the IP block implementation.
Table 20-10. USART Register Memory Map
Offset Register Name Access Reset
0x0000 Control Register CR Write-only 0x00000000
0x0004 Mode Register MR Read-write 0x00000000
0x0008 Interrupt Enable Register IER Write-only 0x00000000
0x000C Interrupt Disable Register IDR Write-only 0x00000000
0x0010 Interrupt Mask Register IMR Read-only 0x00000000
0x0014 Channel Status Register CSR Read-only 0x00000000
0x0018 Receiver Holding Register RHR Read-only 0x00000000
0x001C Transmitter Holding Register THR Write-only 0x00000000
0x0020 Baud Rate Generator Register BRGR Read-write 0x00000000
0x0024 Receiver Time-out Register RTOR Read-write 0x00000000
0x0028 Transmitter Timeguard Register TTGR Read-write 0x00000000
0x0054 LIN Mode Register LINMR Read-write 0x00000000
0x0058 LIN Identifier Register LINIR Read-write 0x00000000
0x00E4 Write Protect Mode Register WPMR Read-write 0x00000000
0x00E8 Write Protect Status Register WPSR Read-only 0x00000000
0x00FC Version Register VERSION Read-only 0x–(1)
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20.7.1 Control Register
Name: CR
Access Type: Write-only
Offset: 0x0
Reset Value: 0x00000000
• LINWKUP: Send LIN Wakeup Signal
Writing a zero to this bit has no effect.
Writing a one to this bit will sends a wakeup signal on the LIN bus.
• LINABT: Abort LIN Transmission
Writing a zero to this bit has no effect.
Writing a one to this bit will abort the current LIN transmission.
• RTSDIS/RCS: Request to Send Disable/Release SPI Chip Select
Writing a zero to this bit has no effect.
Writing a one to this bit when USART is not in SPI master mode drives RTS pin high.
Writing a one to this bit when USART is in SPI master mode releases NSS (RTS pin).
• RTSEN/FCS: Request to Send Enable/Force SPI Chip Select
Writing a zero to this bit has no effect.
Writing a one to this bit when USART is not in SPI master mode drives RTS low.
Writing a one to this bit when USART is in SPI master mode when;
FCS=0: has no effect.
FCS=1: forces NSS (RTS pin) low, even if USART is not transmitting, in order to address SPI slave devices supporting the
CSAAT Mode (Chip Select Active After Transfer).
• RETTO: Rearm Time-out
Writing a zero to this bit has no effect.
Writing a one to this bit reloads the time-out counter and clears CSR.TIMEOUT.
• RSTNACK: Reset Non Acknowledge
Writing a zero to this bit has no effect.
Writing a one to this bit clears CSR.NACK.
• SENDA: Send Address
Writing a zero to this bit has no effect.
Writing a one to this bit will in multidrop mode send the next character written to THR as an address.
• STTTO: Start Time-out
Writing a zero to this bit has no effect.
Writing a one to this bit will abort any current time-out count down, and trigger a new count down when the next character has
been received. CSR.TIMEOUT is also cleared.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
– – LINWKUP LINABT RTSDIS/RCS RTSEN/FCS – –
15 14 13 12 11 10 9 8
RETTO RSTNACK – SENDA STTTO STPBRK STTBRK RSTSTA
76543210
TXDIS TXEN RXDIS RXEN RSTTX RSTRX – –
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• STPBRK: Stop Break
Writing a zero to this bit has no effect.
Writing a one to this bit will stop the generation of break signal characters, and then send ones for TTGR.TG duration, or at least
12 bit periods. No effect if no break is being transmitted.
• STTBRK: Start Break
Writing a zero to this bit has no effect.
Writing a one to this bit will start transmission of break characters when current characters present in THR and the transmit shift
register have been sent. No effect if a break signal is already being generated.
• RSTSTA: Reset Status Bits
Writing a zero to this bit has no effect.
Writing a one to this bit will clear the following bits in CSR: PARE, FRAME, OVRE, LINBE, LINSFE, LINIPE, LINCE, LINSNRE,
and RXBRK.
• TXDIS: Transmitter Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the transmitter.
• TXEN: Transmitter Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the transmitter if TXDIS is zero.
• RXDIS: Receiver Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the receiver.
• RXEN: Receiver Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the receiver if RXDIS is zero.
• RSTTX: Reset Transmitter
Writing a zero to this bit has no effect.
Writing a one to this bit will reset the transmitter.
• RSTRX: Reset Receiver
Writing a zero to this bit has no effect.
Writing a one to this bit will reset the receiver.
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20.7.2 Mode Register
Name: MR
Access Type: Read-write
Offset: 0x4
Reset Value: 0x00000000
This register can only be written if the WPEN bit is cleared in the Write Protect Mode Register.
• INACK: Inhibit Non Acknowledge
0: The NACK is generated.
1: The NACK is not generated.
• OVER: Oversampling Mode
0: Oversampling at 16 times the baud rate.
1: Oversampling at 8 times the baud rate.
• CLKO: Clock Output Select
0: The USART does not drive the CLK pin.
1: The USART drives the CLK pin unless USCLKS selects the external clock.
• MODE9: 9-bit Character Length
0: CHRL defines character length.
1: 9-bit character length.
• MSBF/CPOL: Bit Order or SPI Clock Polarity
If USART does not operate in SPI Mode:
MSBF=0: Least Significant Bit is sent/received first.
MSBF=1: Most Significant Bit is sent/received first.
If USART operates in SPI Mode, CPOL is used with CPHA to produce the required clock/data relationship between devices.
CPOL=0: The inactive state value of CLK is logic level zero.
CPOL=1: The inactive state value of CLK is logic level one.
31 30 29 28 27 26 25 24
––––– –
23 22 21 20 19 18 17 16
– – – INACK OVER CLKO MODE9 MSBF/CPOL
15 14 13 12 11 10 9 8
CHMODE NBSTOP PAR SYNC/CPHA
76543210
CHRL USCLKS MODE
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• CHMODE: Channel Mode
• NBSTOP: Number of Stop Bits
• PAR: Parity Type
• SYNC/CPHA: Synchronous Mode Select or SPI Clock Phase
If USART does not operate in SPI Mode (MODE is 0xE and 0xF):
SYNC = 0: USART operates in Asynchronous Mode.
SYNC = 1: USART operates in Synchronous Mode.
If USART operates in SPI Mode, CPHA determines which edge of CLK causes data to change and which edge causes data to
be captured. CPHA is used with CPOL to produce the required clock/data relationship between master and slave devices.
CPHA = 0: Data is changed on the leading edge of CLK and captured on the following edge of CLK.
CPHA = 1: Data is captured on the leading edge of CLK and changed on the following edge of CLK.
Table 20-11.
CHMODE Mode Description
0 0 Normal Mode
0 1 Automatic Echo. Receiver input is connected to the TXD pin.
1 0 Local Loopback. Transmitter output is connected to the Receiver input.
1 1 Remote Loopback. RXD pin is internally connected to the TXD pin.
Table 20-12.
NBSTOP Asynchronous (SYNC=0) Synchronous (SYNC=1)
0 0 1 stop bit 1 stop bit
0 1 1.5 stop bits Reserved
1 0 2 stop bits 2 stop bits
1 1 Reserved Reserved
Table 20-13.
PAR Parity Type
0 0 0 Even parity
0 0 1 Odd parity
0 1 0 Parity forced to 0 (Space)
0 1 1 Parity forced to 1 (Mark)
1 0 x No parity
1 1 x Multidrop mode
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• CHRL: Character Length.
• USCLKS: Clock Selection
Note: 1. The value of DIV is device dependent. Please refer to the Module Configuration section at the end of this chapter.
• MODE
Table 20-14.
CHRL Character Length
0 0 5 bits
0 1 6 bits
1 0 7 bits
1 1 8 bits
Table 20-15.
USCLKS Selected Clock
0 0 CLK_USART
0 1 CLK_USART/DIV(1)
1 0 Reserved
1 1 CLK
Table 20-16.
MODE Mode of the USART
0 0 0 0 Normal
0 0 1 0 Hardware Handshaking
1 0 1 0 LIN Master
1 0 1 1 LIN Slave
1 1 1 0 SPI Master
1 1 1 1 SPI Slave
Others Reserved
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20.7.3 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x8
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
– – LINSNRE LINCE LINIPE LINISFE LINBE –
23 22 21 20 19 18 17 16
– – – – CTSIC – – –
15 14 13 12 11 10 9 8
LINTC LINID NACK/LINBK RXBUFF – ITER/UNRE TXEMPTY TIMEOUT
76543210
PARE FRAME OVRE – – RXBRK TXRDY RXRDY
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20.7.4 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0xC
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
– – LINSNRE LINCE LINIPE LINISFE LINBE –
23 22 21 20 19 18 17 16
– – – – CTSIC – – –
15 14 13 12 11 10 9 8
LINTC LINID NACK/LINBK RXBUFF – ITER/UNRE TXEMPTY TIMEOUT
76543210
PARE FRAME OVRE – – RXBRK TXRDY RXRDY
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20.7.5 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x10
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
– – LINSNRE LINCE LINIPE LINISFE LINBE –
23 22 21 20 19 18 17 16
– – – – CTSIC – – –
15 14 13 12 11 10 9 8
LINTC LINID NACK/LINBK RXBUFF – ITER/UNRE TXEMPTY TIMEOUT
76543210
PARE FRAME OVRE – – RXBRK TXRDY RXRDY
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20.7.6 Channel Status Register
Name: CSR
Access Type: Read-only
Offset: 0x14
Reset Value: 0x00000000
• LINSNRE: LIN Slave Not Responding Error
0: No LIN Slave Not Responding Error has been detected since the last RSTSTA.
1: A LIN Slave Not Responding Error has been detected since the last RSTSTA.
• LINCE: LIN Checksum Error
0: No LIN Checksum Error has been detected since the last RSTSTA.
1: A LIN Checksum Error has been detected since the last RSTSTA.
• LINIPE: LIN Identifier Parity Error
0: No LIN Identifier Parity Error has been detected since the last RSTSTA.
1: A LIN Identifier Parity Error has been detected since the last RSTSTA.
• LINISFE: LIN Inconsistent Sync Field Error
0: No LIN Inconsistent Sync Field Error has been detected since the last RSTSTA
1: The USART is configured as a Slave node and a LIN Inconsistent Sync Field Error has been detected since the last RSTSTA.
• LINBE: LIN Bit Error
0: No Bit Error has been detected since the last RSTSTA.
1: A Bit Error has been detected since the last RSTSTA.
• CTS: Image of CTS Input
0: CTS is low.
1: CTS is high.
• CTSIC: Clear to Send Input Change Flag
0: No change has been detected on the CTS pin since the last CSR read.
1: At least one change has been detected on the CTS pin since the last CSR read.
• LINTC: LIN Transfer Completed
0: The USART is either idle or a LIN transfer is ongoing.
1: A LIN transfer has been completed since the last RSTSTA.
• LINID: LIN Identifier
0: No LIN Identifier has been sent or received.
1: A LIN Identifier has been sent (master) or received (slave), since the last RSTSTA.
• NACK: Non Acknowledge
0: No Non Acknowledge has been detected since the last RSTNACK.
1: At least one Non Acknowledge has been detected since the last RSTNACK.
• RXBUFF: Reception Buffer Full
0: The Buffer Full signal from the Peripheral DMA Controller channel is inactive.
31 30 29 28 27 26 25 24
– – LINSNRE LINCE LINIPE LINISFE LINBE –
23 22 21 20 19 18 17 16
CTS – – – CTSIC – – –
15 14 13 12 11 10 9 8
LINTC LINID NACK/LINBK RXBUFF – ITER/UNRE TXEMPTY TIMEOUT
76543210
PARE FRAME OVRE – – RXBRK TXRDY RXRDY
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1: The Buffer Full signal from the Peripheral DMA Controller channel is active.
• ITER/UNRE: Max number of Repetitions Reached or SPI Underrun Error
If USART does not operate in SPI Slave Mode:
ITER=0: Maximum number of repetitions has not been reached since the last RSTSTA.
ITER=1: Maximum number of repetitions has been reached since the last RSTSTA.
If USART operates in SPI Slave Mode:
UNRE=0: No SPI underrun error has occurred since the last RSTSTA.
UNRE=1: At least one SPI underrun error has occurred since the last RSTSTA.
• TXEMPTY: Transmitter Empty
0: The transmitter is either disabled or there are characters in THR, or in the transmit shift register.
1: There are no characters in neither THR, nor in the transmit shift register.
• TIMEOUT: Receiver Time-out
0: There has not been a time-out since the last Start Time-out command (CR.STTTO), or RTOR.TO is zero.
1: There has been a time-out since the last Start Time-out command.
• PARE: Parity Error
0: Either no parity error has been detected, or the parity bit is a zero in multidrop mode, since the last RSTSTA.
1: Either at least one parity error has been detected, or the parity bit is a one in multidrop mode, since the last RSTSTA.
• FRAME: Framing Error
0: No stop bit has been found as low since the last RSTSTA.
1: At least one stop bit has been found as low since the last RSTSTA.
• OVRE: Overrun Error
0: No overrun error has occurred since the last RSTSTA.
1: At least one overrun error has occurred since the last RSTSTA.
• RXBRK: Break Received/End of Break
0: No Break received or End of Break detected since the last RSTSTA.
1: Break received or End of Break detected since the last RSTSTA.
• TXRDY: Transmitter Ready
0: The transmitter is either disabled, or a character in THR is waiting to be transferred to the transmit shift register, or an
STTBRK command has been requested. As soon as the transmitter is enabled, TXRDY becomes one.
1: There is no character in the THR.
• RXRDY: Receiver Ready
0: The receiver is either disabled, or no complete character has been received since the last read of RHR. If characters were
being received when the receiver was disabled, RXRDY changes to 1 when the receiver is enabled.
1: At least one complete character has been received and RHR has not yet been read.
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20.7.7 Receiver Holding Register
Name: RHR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x00000000
• RXCHR: Received Character
Last received character.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
––––––––
15 14 13 12 11 10 9 8
– – – – – – – RXCHR[8]
76543210
RXCHR[7:0]
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20.7.8 Transmitter Holding Register
Name: THR
Access Type: Write-only
Offset: 0x1C
Reset Value: 0x00000000
• TXCHR: Character to be Transmitted
If TXRDY is zero this field contains the next character to be transmitted.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
––––––––
15 14 13 12 11 10 9 8
– – – – – – – TXCHR[8]
76543210
TXCHR[7:0]
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20.7.9 Baud Rate Generator Register
Name: BRGR
Access Type: Read-write
Offset: 0x20
Reset Value: 0x00000000
This register can only be written to if write protection is disabled, see ”Write Protect Mode Register” on page 482.
• FP: Fractional Part
0: Fractional divider is disabled.
1 - 7: Baud rate resolution, defined by FP x 1/8.
• CD: Clock Divider
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
– – – – – FP
15 14 13 12 11 10 9 8
CD[15:8]
76543210
CD[7:0]
Table 20-17.
CD
SYNC = 0
SYNC = 1
or
MODE = SPI
(Master or Slave)
OVER = 0 OVER = 1
0 Baud Rate Clock Disabled
1 to 65535
Baud Rate =
Selected Clock/16/CD
Baud Rate =
Selected Clock/8/CD
Baud Rate =
Selected Clock /CD
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20.7.10 Receiver Time-out Register
Name: RTOR
Access Type: Read-write
Offset: 0x24
Reset Value: 0x00000000
This register can only be written to if write protection is disabled, see ”Write Protect Mode Register” on page 482.
• TO: Time-out Value
0: The receiver Time-out is disabled.
1 - 131071: The receiver Time-out is enabled and the time-out delay is TO x bit period.
Note that the size of the TO counter is device dependent, see the Module Configuration section.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
– – – – – – – TO[16]
15 14 13 12 11 10 9 8
TO[15:8]
76543210
TO[7:0]
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20.7.11 Transmitter Timeguard Register
Name: TTGR
Access Type: Read-write
Offset: 0x28
Reset Value: 0x00000000
This register can only be written to if write protection is disabled, see ”Write Protect Mode Register” on page 482.
• TG: Timeguard Value
0: The transmitter Timeguard is disabled.
1 - 255: The transmitter timeguard is enabled and the timeguard delay is TG x bit period.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
––––––––
15 14 13 12 11 10 9 8
––––––––
76543210
TG
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20.7.12 LIN Mode Register
Name: LINMR
Access Type: Read-write
Offset: 0x54
Reset Value: 0x00000000
• PDCM: Peripheral DMA Controller Mode
0: The LIN mode register is not written by the Peripheral DMA Controller.
1: The LIN mode register is, except for this bit, written by the Peripheral DMA Controller.
• DLC: Data Length Control
0 - 255: If DLM=0 this field defines the response data length to DLC+1 bytes.
• WKUPTYP: Wakeup Signal Type
0: Writing a one to CR.LINWKUP will send a LIN 2.0 wakeup signal.
1: Writing a one to CR.LINWKUP will send a LIN 1.3 wakeup signal.
• FSDIS: Frame Slot Mode Disable
0: The Frame Slot mode is enabled.
1: The Frame Slot mode is disabled.
• DLM: Data Length Mode
0: The response data length is defined by DLC.
1: The response data length is defined by bits 4 and 5 of the Identifier (LINIR.IDCHR).
• CHKTYP: Checksum Type
0: LIN 2.0 “Enhanced” checksum
1: LIN 1.3 “Classic” checksum
• CHKDIS: Checksum Disable
0: Checksum is automatically computed and sent when master, and checked when slave.
1: Checksum is not computed and sent, nor checked.
• PARDIS: Parity Disable
0: Identifier parity is automatically computed and sent when master, and checked when slave.
1: Identifier parity is not computed and sent, nor checked.
• NACT: LIN Node Action
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
– – – – – – – PDCM
15 14 13 12 11 10 9 8
DLC
76543210
WKUPTYP FSDIS DLM CHKTYP CHKDIS PARDIS NACT
Table 20-18.
NACT Mode Description
0 0 PUBLISH: The USART transmits the response.
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0 1 SUBSCRIBE: The USART receives the response.
1 0 IGNORE: The USART does not transmit and does not receive the response.
1 1 Reserved
Table 20-18.
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20.7.13 LIN Identifier Register
Name: LINIR
Access Type: Read-write or Read-only
Offset: 0x58
Reset Value: 0x00000000
• IDCHR: Identifier Character
If USART is in LIN master mode, the IDCHR field is read-write, and its value is the Identifier character to be transmitted.
If USART is in LIN slave mode, the IDCHR field is read-only, and its value is the last received Identifier character.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
––––––––
15 14 13 12 11 10 9 8
––––––––
76543210
IDCHR
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20.7.14 Write Protect Mode Register
Register Name: WPMR
Access Type: Read-write
Offset: 0xE4
Reset Value: See Table 20-10
• WPKEY: Write Protect KEY
Has to be written to 0x555341 (“USA” in ASCII) in order to successfully write WPEN. Always reads as zero.
• WPEN: Write Protect Enable
0 = Write protection disabled.
1 = Write protection enabled.
Protects the registers:
• ”Mode Register” on page 466
• ”Baud Rate Generator Register” on page 476
• ”Receiver Time-out Register” on page 477
• ”Transmitter Timeguard Register” on page 478
31 30 29 28 27 26 25 24
WPKEY[23:16]
23 22 21 20 19 18 17 16
WPKEY[15:8]
15 14 13 12 11 10 9 8
WPKEY[7:0]
76543210
— — — — — — — WPEN
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20.7.15 Write Protect Status Register
Register Name: WPSR
Access Type: Read-only
Offset: 0xE8
Reset Value: See Table 20-10
• WPVSRC: Write Protect Violation Source
If WPVS=1 this field indicates which write-protected register was unsuccessfully written to, either by address offset or code.
• WPVS: Write Protect Violation Status
0= No write protect violation has occurred since the last WPSR read.
1= A write protect violation has occurred since the last WPSR read.
Note: Reading WPSR automatically clears all fields.
31 30 29 28 27 26 25 24
————————
23 22 21 20 19 18 17 16
WPVSRC[15:8]
15 14 13 12 11 10 9 8
WPVSRC[7:0]
76543210
— — — — — — — WPVS
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20.7.16 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0xFC
Reset Value: -
• MFN
Reserved. No functionality associated.
• VERSION
Version of the module. No functionality associated.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
– – – – MFN
15 14 13 12 11 10 9 8
– – – – VERSION[11:8]
76543210
VERSION[7:0]
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20.8 Module Configuration
The specific configuration for each USART instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 20-19. USART Configuration
Feature USART0 USART1 USART2 USART3
Receiver Time-out Counter Size
(Size of the RTOR.TO field) 17 bit 17 bit 17 bit 17 bit
DIV Value for divided CLK_USART 8 8 8 8
Table 20-20. USART Clocks
Module Name Clock Name Description
USART0 CLK_USART0 Clock for the USART0 bus interface
USART1 CLK_USART1 Clock for the USART1 bus interface
USART2 CLK_USART2 Clock for the USART2 bus interface
USART3 CLK_USART3 Clock for the USART3 bus interface
Table 20-21. Register Reset Values
Register Reset Value
VERSION 0x00000440
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21. Serial Peripheral Interface (SPI)
Rev: 2.1.1.3
21.1 Features
• Compatible with an embedded 32-bit microcontroller
• Supports communication with serial external devices
– Four chip selects with external decoder support allow communication with up to 15
peripherals
– Serial memories, such as DataFlash and 3-wire EEPROMs
– Serial peripherals, such as ADCs, DACs, LCD controllers, CAN controllers and Sensors
– External co-processors
• Master or Slave Serial Peripheral Bus Interface
– 4 - to 16-bit programmable data length per chip select
– Programmable phase and polarity per chip select
– Programmable transfer delays between consecutive transfers and between clock and data
per chip select
– Programmable delay between consecutive transfers
– Selectable mode fault detection
• Connection to Peripheral DMA Controller channel capabilities optimizes data transfers
– One channel for the receiver, one channel for the transmitter
– Next buffer support
– Four character FIFO in reception
21.2 Overview
The Serial Peripheral Interface (SPI) circuit is a synchronous serial data link that provides communication
with external devices in Master or Slave mode. It also enables communication
between processors if an external processor is connected to the system.
The Serial Peripheral Interface is essentially a shift register that serially transmits data bits to
other SPIs. During a data transfer, one SPI system acts as the “master”' which controls the data
flow, while the other devices act as “slaves'' which have data shifted into and out by the master.
Different CPUs can take turn being masters (Multiple Master Protocol opposite to Single Master
Protocol where one CPU is always the master while all of the others are always slaves) and one
master may simultaneously shift data into multiple slaves. However, only one slave may drive its
output to write data back to the master at any given time.
A slave device is selected when the master asserts its NSS signal. If multiple slave devices
exist, the master generates a separate slave select signal for each slave (NPCS).
The SPI system consists of two data lines and two control lines:
• Master Out Slave In (MOSI): this data line supplies the output data from the master shifted
into the input(s) of the slave(s).
• Master In Slave Out (MISO): this data line supplies the output data from a slave to the input of
the master. There may be no more than one slave transmitting data during any particular
transfer.
• Serial Clock (SPCK): this control line is driven by the master and regulates the flow of the
data bits. The master may transmit data at a variety of baud rates; the SPCK line cycles once
for each bit that is transmitted.
• Slave Select (NSS): this control line allows slaves to be turned on and off by hardware.
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21.3 Block Diagram
Figure 21-1. SPI Block Diagram
21.4 Application Block Diagram
Figure 21-2. Application Block Diagram: Single Master/Multiple Slave Implementation
Spi Interface
Interrupt Control
Peripheral DMA
Controller
I/O
Controller
CLK_SPI
Peripheral Bus
SPI Interrupt
SPCK
NPCS3
NPCS2
NPCS1
NPCS0/NSS
MOSI
MISO
Slave 0
Slave 2
Slave 1
SPCK
NPCS3
NPCS2
NPCS1
NPCS0
MOSI
MISO
Spi Master
SPCK
NSS
MOSI
MISO
SPCK
NSS
MOSI
MISO
SPCK
NSS
MOSI
MISO
NC
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21.5 I/O Lines Description
21.6 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
21.6.1 I/O Lines
The pins used for interfacing the compliant external devices may be multiplexed with I/O lines.
The user must first configure the I/O Controller to assign the SPI pins to their peripheral
functions.
21.6.2 Clocks
The clock for the SPI bus interface (CLK_SPI) is generated by the Power Manager. This clock is
enabled at reset, and can be disabled in the Power Manager. It is recommended to disable the
SPI before disabling the clock, to avoid freezing the SPI in an undefined state.
21.6.3 Interrupts
The SPI interrupt request line is connected to the interrupt controller. Using the SPI interrupt
requires the interrupt controller to be programmed first.
21.7 Functional Description
21.7.1 Modes of Operation
The SPI operates in master mode or in slave mode.
Operation in master mode is configured by writing a one to the Master/Slave Mode bit in the
Mode Register (MR.MSTR). The pins NPCS0 to NPCS3 are all configured as outputs, the SPCK
pin is driven, the MISO line is wired on the receiver input and the MOSI line driven as an output
by the transmitter.
If the MR.MSTR bit is written to zero, the SPI operates in slave mode. The MISO line is driven by
the transmitter output, the MOSI line is wired on the receiver input, the SPCK pin is driven by the
transmitter to synchronize the receiver. The NPCS0 pin becomes an input, and is used as a
Slave Select signal (NSS). The pins NPCS1 to NPCS3 are not driven and can be used for other
purposes.
The data transfers are identically programmable for both modes of operations. The baud rate
generator is activated only in master mode.
Table 21-1. I/O Lines Description
Pin Name Pin Description
Type
Master Slave
MISO Master In Slave Out Input Output
MOSI Master Out Slave In Output Input
SPCK Serial Clock Output Input
NPCS1-NPCS3 Peripheral Chip Selects Output Unused
NPCS0/NSS Peripheral Chip Select/Slave Select Output Input
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21.7.2 Data Transfer
Four combinations of polarity and phase are available for data transfers. The clock polarity is
configured with the Clock Polarity bit in the Chip Select Registers (CSRn.CPOL). The clock
phase is configured with the Clock Phase bit in the CSRn registers (CSRn.NCPHA). These two
bits determine the edges of the clock signal on which data is driven and sampled. Each of the
two bits has two possible states, resulting in four possible combinations that are incompatible
with one another. Thus, a master/slave pair must use the same parameter pair values to communicate.
If multiple slaves are used and fixed in different configurations, the master must
reconfigure itself each time it needs to communicate with a different slave.
Table 21-2 on page 489 shows the four modes and corresponding parameter settings.
Figure 21-3 on page 489 and Figure 21-4 on page 490 show examples of data transfers.
Figure 21-3. SPI Transfer Format (NCPHA = 1, 8 bits per transfer)
Table 21-2. SPI modes
SPI Mode CPOL NCPHA
0 01
1 00
2 11
3 10
SPCK cycle (for reference) 1 4 2 3 5 8 6 7
SPCK
(CPOL = 0)
NSS
(to slave)
MISO
(from slave)
MOSI
(from master)
SPCK
(CPOL = 1)
MSB 6 4 5 LSB 3 2 1
MSB 6 5 4 3 2 1 LSB ***
*** Not Defined, but normaly MSB of previous character received
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Figure 21-4. SPI Transfer Format (NCPHA = 0, 8 bits per transfer)
21.7.3 Master Mode Operations
When configured in master mode, the SPI uses the internal programmable baud rate generator
as clock source. It fully controls the data transfers to and from the slave(s) connected to the SPI
bus. The SPI drives the chip select line to the slave and the serial clock signal (SPCK).
The SPI features two holding registers, the Transmit Data Register (TDR) and the Receive Data
Register (RDR), and a single Shift Register. The holding registers maintain the data flow at a
constant rate.
After enabling the SPI, a data transfer begins when the processor writes to the TDR register.
The written data is immediately transferred in the Shift Register and transfer on the SPI bus
starts. While the data in the Shift Register is shifted on the MOSI line, the MISO line is sampled
and shifted in the Shift Register. Transmission cannot occur without reception.
Before writing to the TDR, the Peripheral Chip Select field in TDR (TDR.PCS) must be written in
order to select a slave.
If new data is written to TDR during the transfer, it stays in it until the current transfer is completed.
Then, the received data is transferred from the Shift Register to RDR, the data in TDR is
loaded in the Shift Register and a new transfer starts.
The transfer of a data written in TDR in the Shift Register is indicated by the Transmit Data Register
Empty bit in the Status Register (SR.TDRE). When new data is written in TDR, this bit is
cleared. The SR.TDRE bit is used to trigger the Transmit Peripheral DMA Controller channel.
The end of transfer is indicated by the Transmission Registers Empty bit in the SR register
(SR.TXEMPTY). If a transfer delay (CSRn.DLYBCT) is greater than zero for the last transfer,
SR.TXEMPTY is set after the completion of said delay. The CLK_SPI can be switched off at this
time.
During reception, received data are transferred from the Shift Register to the reception FIFO.
The FIFO can contain up to 4 characters (both Receive Data and Peripheral Chip Select fields).
While a character of the FIFO is unread, the Receive Data Register Full bit in SR remains high
(SR.RDRF). Characters are read through the RDR register. If the four characters stored in the
FIFO are not read and if a new character is stored, this sets the Overrun Error Status bit in the
SR register (SR.OVRES). The procedure to follow in such a case is described in Section
21.7.3.8.
SPCK cycle (for reference) 1 4 2 3 5 8 6 7
SPCK
(CPOL = 0)
NSS
(to slave)
MISO
(from slave)
MOSI
(from master)
SPCK
(CPOL = 1)
MSB 6 4 5 LSB 3 2 1
6 5 4 3 2 1 LSB
*** Not Defined, but normaly LSB of previous character transmitted
*** MSB
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Figure 21-5 on page 491shows a block diagram of the SPI when operating in master mode. Figure
21-6 on page 492 shows a flow chart describing how transfers are handled.
21.7.3.1 Master mode block diagram
Figure 21-5. Master Mode Block Diagram
Baud Rate Generator
RXFIFOEN
4 – Character FIFO
Shift Register
TDRE
RXFIFOEN
4 – Character FIFO
PS
PCSDEC
Current
Peripheral
MODF
MODFDIS
MSTR
SCBR
CSR0..3
CSR0..3
CPOL
NCPHA
BITS
RDR
RD
RDRF
OVRES
TD
TDR
RDR
CSAAT
CSNAAT
CSR0..3
PCS
MR
PCS
TDR
SPCK CLK_SPI
MISO MOSI LSB MSB
NPCS1
NPCS2
NPCS3
NPCS0
SPI
Clock
0
1
0
1
0
1
NPCS0
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21.7.3.2 Master mode flow diagram
Figure 21-6. Master Mode Flow Diagram
SPI Enable
CSAAT ?
PS ?
1
0
0
1
1
NPCS = TDR(PCS) NPCS = MR(PCS)
Delay DLYBS
Serializer = TDR(TD)
TDRE = 1
Data Transfer
RDR(RD) = Serializer
RDRF = 1
TDRE ?
NPCS = 0xF
Delay DLYBCS
Fixed
peripheral
Variable
peripheral
Delay DLYBCT
0
1 CSAAT ?
0
TDRE ?
1
0
PS ?
0
1
TDR(PCS)
= NPCS ?
no
yes MR(PCS)
= NPCS ?
no
NPCS = 0xF
Delay DLYBCS
NPCS = TDR(PCS)
NPCS = 0xF
Delay DLYBCS
NPCS = MR(PCS),
TDR(PCS)
Fixed
peripheral
Variable
peripheral
- NPCS defines the current Chip Select
- CSAAT, DLYBS, DLYBCT refer to the fields of the
Chip Select Register corresponding to the Current Chip Select
- When NPCS is 0xF, CSAAT is 0.
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21.7.3.3 Clock generation
The SPI Baud rate clock is generated by dividing the CLK_SPI , by a value between 1 and 255.
This allows a maximum operating baud rate at up to CLK_SPI and a minimum operating baud
rate of CLK_SPI divided by 255.
Writing the Serial Clock Baud Rate field in the CSRn registers (CSRn.SCBR) to zero is forbidden.
Triggering a transfer while CSRn.SCBR is zero can lead to unpredictable results.
At reset, CSRn.SCBR is zero and the user has to configure it at a valid value before performing
the first transfer.
The divisor can be defined independently for each chip select, as it has to be configured in the
CSRn.SCBR field. This allows the SPI to automatically adapt the baud rate for each interfaced
peripheral without reprogramming.
21.7.3.4 Transfer delays
Figure 21-7 on page 493 shows a chip select transfer change and consecutive transfers on the
same chip select. Three delays can be configured to modify the transfer waveforms:
• The delay between chip selects, programmable only once for all the chip selects by writing to
the Delay Between Chip Selects field in the MR register (MR.DLYBCS). Allows insertion of a
delay between release of one chip select and before assertion of a new one.
• The delay before SPCK, independently programmable for each chip select by writing the
Delay Before SPCK field in the CSRn registers (CSRn.DLYBS). Allows the start of SPCK to
be delayed after the chip select has been asserted.
• The delay between consecutive transfers, independently programmable for each chip select
by writing the Delay Between Consecutive Transfers field in the CSRn registers
(CSRn.DLYBCT). Allows insertion of a delay between two transfers occurring on the same
chip select
These delays allow the SPI to be adapted to the interfaced peripherals and their speed and bus
release time.
Figure 21-7. Programmable Delays
DLYBCS DLYBS DLYBCT DLYBCT
Chip Select 1
Chip Select 2
SPCK
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21.7.3.5 Peripheral selection
The serial peripherals are selected through the assertion of the NPCS0 to NPCS3 signals. By
default, all the NPCS signals are high before and after each transfer.
The peripheral selection can be performed in two different ways:
• Fixed Peripheral Select: SPI exchanges data with only one peripheral
• Variable Peripheral Select: Data can be exchanged with more than one peripheral
Fixed Peripheral Select is activated by writing a zero to the Peripheral Select bit in MR (MR.PS).
In this case, the current peripheral is defined by the MR.PCS field and the TDR.PCS field has no
effect.
Variable Peripheral Select is activated by writing a one to the MR.PS bit . The TDR.PCS field is
used to select the current peripheral. This means that the peripheral selection can be defined for
each new data.
The Fixed Peripheral Selection allows buffer transfers with a single peripheral. Using the Peripheral
DMA Controller is an optimal means, as the size of the data transfer between the memory
and the SPI is either 4 bits or 16 bits. However, changing the peripheral selection requires the
Mode Register to be reprogrammed.
The Variable Peripheral Selection allows buffer transfers with multiple peripherals without reprogramming
the MR register. Data written to TDR is 32-bits wide and defines the real data to be
transmitted and the peripheral it is destined to. Using the Peripheral DMA Controller in this mode
requires 32-bit wide buffers, with the data in the LSBs and the PCS and LASTXFER fields in the
MSBs, however the SPI still controls the number of bits (8 to16) to be transferred through MISO
and MOSI lines with the CSRn registers. This is not the optimal means in term of memory size
for the buffers, but it provides a very effective means to exchange data with several peripherals
without any intervention of the processor.
21.7.3.6 Peripheral chip select decoding
The user can configure the SPI to operate with up to 15 peripherals by decoding the four Chip
Select lines, NPCS0 to NPCS3 with an external logic. This can be enabled by writing a one to
the Chip Select Decode bit in the MR register (MR.PCSDEC).
When operating without decoding, the SPI makes sure that in any case only one chip select line
is activated, i.e. driven low at a time. If two bits are defined low in a PCS field, only the lowest
numbered chip select is driven low.
When operating with decoding, the SPI directly outputs the value defined by the PCS field of
either the MR register or the TDR register (depending on PS).
As the SPI sets a default value of 0xF on the chip select lines (i.e. all chip select lines at one)
when not processing any transfer, only 15 peripherals can be decoded.
The SPI has only four Chip Select Registers, not 15. As a result, when decoding is activated,
each chip select defines the characteristics of up to four peripherals. As an example, the CRS0
register defines the characteristics of the externally decoded peripherals 0 to 3, corresponding to
the PCS values 0x0 to 0x3. Thus, the user has to make sure to connect compatible peripherals
on the decoded chip select lines 0 to 3, 4 to 7, 8 to 11 and 12 to 14.
21.7.3.7 Peripheral deselection
When operating normally, as soon as the transfer of the last data written in TDR is completed,
the NPCS lines all rise. This might lead to runtime error if the processor is too long in responding
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to an interrupt, and thus might lead to difficulties for interfacing with some serial peripherals
requiring the chip select line to remain active during a full set of transfers.
To facilitate interfacing with such devices, the CSRn registers can be configured with the Chip
Select Active After Transfer bit written to one (CSRn.CSAAT) . This allows the chip select lines
to remain in their current state (low = active) until transfer to another peripheral is required.
When the CSRn.CSAAT bit is written to qero, the NPCS does not rise in all cases between two
transfers on the same peripheral. During a transfer on a Chip Select, the SR.TDRE bit rises as
soon as the content of the TDR is transferred into the internal shifter. When this bit is detected
the TDR can be reloaded. If this reload occurs before the end of the current transfer and if the
next transfer is performed on the same chip select as the current transfer, the Chip Select is not
de-asserted between the two transfers. This might lead to difficulties for interfacing with some
serial peripherals requiring the chip select to be de-asserted after each transfer. To facilitate
interfacing with such devices, the CSRn registers can be configured with the Chip Select Not
Active After Transfer bit (CSRn.CSNAAT) written to one. This allows to de-assert systematically
the chip select lines during a time DLYBCS. (The value of the CSRn.CSNAAT bit is taken into
account only if the CSRn.CSAAT bit is written to zero for the same Chip Select).
Figure 21-8 on page 496 shows different peripheral deselection cases and the effect of the
CSRn.CSAAT and CSRn.CSNAAT bits.
21.7.3.8 FIFO management
A FIFO has been implemented in Reception FIFO (both in master and in slave mode), in order to
be able to store up to 4 characters without causing an overrun error. If an attempt is made to
store a fifth character, an overrun error rises. If such an event occurs, the FIFO must be flushed.
There are two ways to Flush the FIFO:
• By performing four read accesses of the RDR (the data read must be ignored)
• By writing a one to the Flush Fifo Command bit in the CR register (CR.FLUSHFIFO).
After that, the SPI is able to receive new data.
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Figure 21-8. Peripheral Deselection
Figure 21-8 on page 496 shows different peripheral deselection cases and the effect of the
CSRn.CSAAT and CSRn.CSNAAT bits.
21.7.3.9 Mode fault detection
The SPI is capable of detecting a mode fault when it is configured in master mode and NPCS0,
MOSI, MISO, and SPCK are configured as open drain through the I/O Controller with either
internal or external pullup resistors. If the I/O Controller does not have open-drain capability,
mode fault detection must be disabled by writing a one to the Mode Fault Detection bit in the MR
A
NPCS[0..3]
Write TDR
TDRE
NPCS[0..3]
Write TDR
TDRE
NPCS[0..3]
Write TDR
TDRE
DLYBCS
PCS = A
DLYBCS
DLYBCT
A
PCS = B
B
DLYBCS
PCS = A
DLYBCS
DLYBCT
A
PCS = B
B
DLYBCS
DLYBCT
PCS=A
A
DLYBCS
DLYBCT
A
PCS = A
A A
DLYBCT
A A
CSAAT = 0 and CSNAAT = 0
DLYBCT
A A
CSAAT = 1 and CSNAAT= 0 / 1
A
DLYBCS
PCS = A
DLYBCT
A A
CSAAT = 0 and CSNAAT = 1
NPCS[0..3]
Write TDR
TDRE
PCS = A
DLYBCT
A A
CSAAT = 0 and CSNAAT = 0
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register (MR.MODFDIS). In systems with open-drain I/O lines, a mode fault is detected when a
low level is driven by an external master on the NPCS0/NSS signal.
When a mode fault is detected, the Mode Fault Error bit in the SR (SR.MODF) is set until the SR
is read and the SPI is automatically disabled until re-enabled by writing a one to the SPI Enable
bit in the CR register (CR.SPIEN).
By default, the mode fault detection circuitry is enabled. The user can disable mode fault detection
by writing a one to the Mode Fault Detection bit in the MR register (MR.MODFDIS).
21.7.4 SPI Slave Mode
When operating in slave mode, the SPI processes data bits on the clock provided on the SPI
clock pin (SPCK).
The SPI waits for NSS to go active before receiving the serial clock from an external master.
When NSS falls, the clock is validated on the serializer, which processes the number of bits
defined by the Bits Per Transfer field of the Chip Select Register 0 (CSR0.BITS). These bits are
processed following a phase and a polarity defined respectively by the CSR0.NCPHA and
CSR0.CPOL bits. Note that the BITS, CPOL, and NCPHA bits of the other Chip Select Registers
have no effect when the SPI is configured in Slave Mode.
The bits are shifted out on the MISO line and sampled on the MOSI line.
When all the bits are processed, the received data is transferred in the Receive Data Register
and the SR.RDRF bit rises. If the RDR register has not been read before new data is received,
the SR.OVRES bit is set. Data is loaded in RDR even if this flag is set. The user has to read the
SR register to clear the SR.OVRES bit.
When a transfer starts, the data shifted out is the data present in the Shift Register. If no data
has been written in the TDR register, the last data received is transferred. If no data has been
received since the last reset, all bits are transmitted low, as the Shift Register resets to zero.
When a first data is written in TDR, it is transferred immediately in the Shift Register and the
SR.TDRE bit rises. If new data is written, it remains in TDR until a transfer occurs, i.e. NSS falls
and there is a valid clock on the SPCK pin. When the transfer occurs, the last data written in
TDR is transferred in the Shift Register and the SR.TDRE bit rises. This enables frequent
updates of critical variables with single transfers.
Then, a new data is loaded in the Shift Register from the TDR. In case no character is ready to
be transmitted, i.e. no character has been written in TDR since the last load from TDR to the
Shift Register, the Shift Register is not modified and the last received character is retransmitted.
In this case the Underrun Error Status bit is set in SR (SR.UNDES).
Figure 21-9 on page 498 shows a block diagram of the SPI when operating in slave mode.
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Figure 21-9. Slave Mode Functional Block Diagram
Shift Register
SPCK
SPIENS
LSB MSB
NSS
MOSI
SPI
Clock
TDRE
TDR
TD
RDRF
OVRES
CSR0
CPOL
NCPHA
BITS
SPIEN
SPIDIS
MISO
UNDES
RDR
RD
4 - Character FIFO
0
1
RXFIFOEN
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21.8 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 21-3. SPI Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Write-only 0x00000000
0x04 Mode Register MR Read/Write 0x00000000
0x08 Receive Data Register RDR Read-only 0x00000000
0x0C Transmit Data Register TDR Write-only 0x00000000
0x10 Status Register SR Read-only 0x00000000
0x14 Interrupt Enable Register IER Write-only 0x00000000
0x18 Interrupt Disable Register IDR Write-only 0x00000000
0x1C Interrupt Mask Register IMR Read-only 0x00000000
0x30 Chip Select Register 0 CSR0 Read/Write 0x00000000
0x34 Chip Select Register 1 CSR1 Read/Write 0x00000000
0x38 Chip Select Register 2 CSR2 Read/Write 0x00000000
0x3C Chip Select Register 3 CSR3 Read/Write 0x00000000
0x E4 Write Protection Control Register WPCR Read/Write 0X00000000
0xE8 Write Protection Status Register WPSR Read-only 0x00000000
0xF8 Features Register FEATURES Read-only - (1)
0xFC Version Register VERSION Read-only - (1)
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21.8.1 Control Register
Name: CR
Access Type: Write-only
Offset: 0x00
Reset Value: 0x00000000
• LASTXFER: Last Transfer
1: The current NPCS will be deasserted after the character written in TD has been transferred. When CSRn.CSAAT is one, this
allows to close the communication with the current serial peripheral by raising the corresponding NPCS line as soon as TD
transfer has completed.
0: Writing a zero to this bit has no effect.
• FLUSHFIFO: Flush Fifo Command
1: If The FIFO Mode is enabled (MR.FIFOEN written to one) and if an overrun error has been detected, this command allows to
empty the FIFO.
0: Writing a zero to this bit has no effect.
• SWRST: SPI Software Reset
1: Writing a one to this bit will reset the SPI. A software-triggered hardware reset of the SPI interface is performed. The SPI is in
slave mode after software reset. Peripheral DMA Controller channels are not affected by software reset.
0: Writing a zero to this bit has no effect.
• SPIDIS: SPI Disable
1: Writing a one to this bit will disable the SPI. As soon as SPIDIS is written to one, the SPI finishes its transfer, all pins are set
in input mode and no data is received or transmitted. If a transfer is in progress, the transfer is finished before the SPI is
disabled. If both SPIEN and SPIDIS are equal to one when the CR register is written, the SPI is disabled.
0: Writing a zero to this bit has no effect.
• SPIEN: SPI Enable
1: Writing a one to this bit will enable the SPI to transfer and receive data.
0: Writing a zero to this bit has no effect.
31 30 29 28 27 26 25 24
- - - - - - - LASTXFER
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - - FLUSHFIFO
76543210
SWRST - - - - - SPIDIS SPIEN
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21.8.2 Mode Register
Name: MR
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• DLYBCS: Delay Between Chip Selects
This field defines the delay from NPCS inactive to the activation of another NPCS. The DLYBCS time guarantees nonoverlapping
chip selects and solves bus contentions in case of peripherals having long data float times.
If DLYBCS is less than or equal to six, six CLK_SPI periods will be inserted by default.
Otherwise, the following equation determines the delay:
• PCS: Peripheral Chip Select
This field is only used if Fixed Peripheral Select is active (PS = 0).
If PCSDEC = 0:
PCS = xxx0NPCS[3:0] = 1110
PCS = xx01NPCS[3:0] = 1101
PCS = x011NPCS[3:0] = 1011
PCS = 0111NPCS[3:0] = 0111
PCS = 1111forbidden (no peripheral is selected)
(x = don’t care)
If PCSDEC = 1:
NPCS[3:0] output signals = PCS.
• LLB: Local Loopback Enable
1: Local loopback path enabled. LLB controls the local loopback on the data serializer for testing in master mode only (MISO is
internally connected on MOSI).
0: Local loopback path disabled.
• RXFIFOEN: FIFO in Reception Enable
1: The FIFO is used in reception (four characters can be stored in the SPI).
31 30 29 28 27 26 25 24
DLYBCS
23 22 21 20 19 18 17 16
- - - - PCS
15 14 13 12 11 10 9 8
--------
76543210
LLB RXFIFOEN - MODFDIS - PCSDEC PS MSTR
Delay Between Chip Selects DLYBCS
CLKSPI = -----------------------
502
32142D–06/2013
ATUC64/128/256L3/4U
0: The FIFO is not used in reception (only one character can be stored in the SPI).
• MODFDIS: Mode Fault Detection
1: Mode fault detection is disabled. If the I/O controller does not have open-drain capability, mode fault detection must be
disabled for proper operation of the SPI.
0: Mode fault detection is enabled.
• PCSDEC: Chip Select Decode
0: The chip selects are directly connected to a peripheral device.
1: The four chip select lines are connected to a 4- to 16-bit decoder.
When PCSDEC equals one, up to 15 Chip Select signals can be generated with the four lines using an external 4- to 16-bit
decoder. The CSRn registers define the characteristics of the 15 chip selects according to the following rules:
CSR0 defines peripheral chip select signals 0 to 3.
CSR1 defines peripheral chip select signals 4 to 7.
CSR2 defines peripheral chip select signals 8 to 11.
CSR3 defines peripheral chip select signals 12 to 14.
• PS: Peripheral Select
1: Variable Peripheral Select.
0: Fixed Peripheral Select.
• MSTR: Master/Slave Mode
1: SPI is in master mode.
0: SPI is in slave mode.
503
32142D–06/2013
ATUC64/128/256L3/4U
21.8.3 Receive Data Register
Name: RDR
Access Type: Read-only
Offset: 0x08
Reset Value: 0x00000000
• RD: Receive Data
Data received by the SPI Interface is stored in this register right-justified. Unused bits read zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
RD[15:8]
76543210
RD[7:0]
504
32142D–06/2013
ATUC64/128/256L3/4U
21.8.4 Transmit Data Register
Name: TDR
Access Type: Write-only
Offset: 0x0C
Reset Value: 0x00000000
• LASTXFER: Last Transfer
1: The current NPCS will be deasserted after the character written in TD has been transferred. When CSRn.CSAAT is one, this
allows to close the communication with the current serial peripheral by raising the corresponding NPCS line as soon as TD
transfer has completed.
0: Writing a zero to this bit has no effect.
This field is only used if Variable Peripheral Select is active (MR.PS = 1).
• PCS: Peripheral Chip Select
If PCSDEC = 0:
PCS = xxx0NPCS[3:0] = 1110
PCS = xx01NPCS[3:0] = 1101
PCS = x011NPCS[3:0] = 1011
PCS = 0111NPCS[3:0] = 0111
PCS = 1111forbidden (no peripheral is selected)
(x = don’t care)
If PCSDEC = 1:
NPCS[3:0] output signals = PCS
This field is only used if Variable Peripheral Select is active (MR.PS = 1).
• TD: Transmit Data
Data to be transmitted by the SPI Interface is stored in this register. Information to be transmitted must be written to the TDR
register in a right-justified format.
31 30 29 28 27 26 25 24
- - - - - - - LASTXFER
23 22 21 20 19 18 17 16
- - - - PCS
15 14 13 12 11 10 9 8
TD[15:8]
76543210
TD[7:0]
505
32142D–06/2013
ATUC64/128/256L3/4U
21.8.5 Status Register
Name: SR
Access Type: Read-only
Offset: 0x10
Reset Value: 0x00000000
• SPIENS: SPI Enable Status
1: This bit is set when the SPI is enabled.
0: This bit is cleared when the SPI is disabled.
• UNDES: Underrun Error Status (Slave Mode Only)
1: This bit is set when a transfer begins whereas no data has been loaded in the TDR register.
0: This bit is cleared when the SR register is read.
• TXEMPTY: Transmission Registers Empty
1: This bit is set when TDR and internal shifter are empty. If a transfer delay has been defined, TXEMPTY is set after the
completion of such delay.
0: This bit is cleared as soon as data is written in TDR.
• NSSR: NSS Rising
1: A rising edge occurred on NSS pin since last read.
0: This bit is cleared when the SR register is read.
• OVRES: Overrun Error Status
1: This bit is set when an overrun has occurred. An overrun occurs when RDR is loaded at least twice from the serializer since
the last read of the RDR.
0: This bit is cleared when the SR register is read.
• MODF: Mode Fault Error
1: This bit is set when a Mode Fault occurred.
0: This bit is cleared when the SR register is read.
• TDRE: Transmit Data Register Empty
1: This bit is set when the last data written in the TDR register has been transferred to the serializer.
0: This bit is cleared when data has been written to TDR and not yet transferred to the serializer.
TDRE equals zero when the SPI is disabled or at reset. The SPI enable command sets this bit to one.
• RDRF: Receive Data Register Full
1: Data has been received and the received data has been transferred from the serializer to RDR since the last read of RDR.
0: No data has been received since the last read of RDR
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - SPIENS
15 14 13 12 11 10 9 8
- - - - - UNDES TXEMPTY NSSR
76543210
- - - - OVRES MODF TDRE RDRF
506
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ATUC64/128/256L3/4U
21.8.6 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - UNDES TXEMPTY NSSR
76543210
- - - - OVRES MODF TDRE RDRF
507
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ATUC64/128/256L3/4U
21.8.7 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x18
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - UNDES TXEMPTY NSSR
76543210
- - - - OVRES MODF TDRE RDRF
508
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ATUC64/128/256L3/4U
21.8.8 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - UNDES TXEMPTY NSSR
76543210
- - - - OVRES MODF TDRE RDRF
509
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ATUC64/128/256L3/4U
21.8.9 Chip Select Register 0
Name: CSR0
Access Type: Read/Write
Offset: 0x30
Reset Value: 0x00000000
• DLYBCT: Delay Between Consecutive Transfers
This field defines the delay between two consecutive transfers with the same peripheral without removing the chip select. The
delay is always inserted after each transfer and before removing the chip select if needed.
When DLYBCT equals zero, no delay between consecutive transfers is inserted and the clock keeps its duty cycle over the
character transfers.
Otherwise, the following equation determines the delay:
• DLYBS: Delay Before SPCK
This field defines the delay from NPCS valid to the first valid SPCK transition.
When DLYBS equals zero, the NPCS valid to SPCK transition is 1/2 the SPCK clock period.
Otherwise, the following equations determine the delay:
• SCBR: Serial Clock Baud Rate
In Master Mode, the SPI Interface uses a modulus counter to derive the SPCK baud rate from the CLK_SPI. The Baud rate is
selected by writing a value from 1 to 255 in the SCBR field. The following equations determine the SPCK baud rate:
Writing the SCBR field to zero is forbidden. Triggering a transfer while SCBR is zero can lead to unpredictable results.
At reset, SCBR is zero and the user has to write it to a valid value before performing the first transfer.
If a clock divider (SCBRn) field is set to one and the other SCBR fields differ from one, access on CSn is correct but no correct
access will be possible on other CS.
31 30 29 28 27 26 25 24
DLYBCT
23 22 21 20 19 18 17 16
DLYBS
15 14 13 12 11 10 9 8
SCBR
76543210
BITS CSAAT CSNAAT NCPHA CPOL
Delay Between Consecutive Transfers 32 DLYBCT
CLKSPI = ------------------------------------
Delay Before SPCK DLYBS
CLKSPI = ---------------------
SPCK Baudrate CLKSPI
SCBR = ---------------------
510
32142D–06/2013
ATUC64/128/256L3/4U
• BITS: Bits Per Transfer
The BITS field determines the number of data bits transferred. Reserved values should not be used.
• CSAAT: Chip Select Active After Transfer
1: The Peripheral Chip Select does not rise after the last transfer is achieved. It remains active until a new transfer is requested
on a different chip select.
0: The Peripheral Chip Select Line rises as soon as the last transfer is achieved.
• CSNAAT: Chip Select Not Active After Transfer (Ignored if CSAAT = 1)
0: The Peripheral Chip Select does not rise between two transfers if the TDR is reloaded before the end of the first transfer and
if the two transfers occur on the same Chip Select.
1: The Peripheral Chip Select rises systematically between each transfer performed on the same slave for a minimal duration of:
(if DLYBCT field is different from 0)
(if DLYBCT field equals 0)
• NCPHA: Clock Phase
1: Data is captured after the leading (inactive-to-active) edge of SPCK and changed on the trailing (active-to-inactive) edge of
SPCK.
0: Data is changed on the leading (inactive-to-active) edge of SPCK and captured after the trailing (active-to-inactive) edge of
SPCK.
NCPHA determines which edge of SPCK causes data to change and which edge causes data to be captured. NCPHA is used
with CPOL to produce the required clock/data relationship between master and slave devices.
• CPOL: Clock Polarity
1: The inactive state value of SPCK is logic level one.
0: The inactive state value of SPCK is logic level zero.
BITS Bits Per Transfer
0000 8
0001 9
0010 10
0011 11
0100 12
0101 13
0110 14
0111 15
1000 16
1001 4
1010 5
1011 6
1100 7
1101 Reserved
1110 Reserved
1111 Reserved
DLYBCS
CLKSPI
-----------------------
DLYBCS + 1
CLKSPI
--------------------------------
511
32142D–06/2013
ATUC64/128/256L3/4U
CPOL is used to determine the inactive state value of the serial clock (SPCK). It is used with NCPHA to produce the required
clock/data relationship between master and slave devices.
512
32142D–06/2013
ATUC64/128/256L3/4U
21.8.10 Chip Select Register 1
Name: CSR1
Access Type: Read/Write
Offset: 0x34
Reset Value: 0x00000000
• DLYBCT: Delay Between Consecutive Transfers
This field defines the delay between two consecutive transfers with the same peripheral without removing the chip select. The
delay is always inserted after each transfer and before removing the chip select if needed.
When DLYBCT equals zero, no delay between consecutive transfers is inserted and the clock keeps its duty cycle over the
character transfers.
Otherwise, the following equation determines the delay:
• DLYBS: Delay Before SPCK
This field defines the delay from NPCS valid to the first valid SPCK transition.
When DLYBS equals zero, the NPCS valid to SPCK transition is 1/2 the SPCK clock period.
Otherwise, the following equations determine the delay:
• SCBR: Serial Clock Baud Rate
In Master Mode, the SPI Interface uses a modulus counter to derive the SPCK baud rate from the CLK_SPI. The Baud rate is
selected by writing a value from 1 to 255 in the SCBR field. The following equations determine the SPCK baud rate:
Writing the SCBR field to zero is forbidden. Triggering a transfer while SCBR is zero can lead to unpredictable results.
At reset, SCBR is zero and the user has to write it to a valid value before performing the first transfer.
If a clock divider (SCBRn) field is set to one and the other SCBR fields differ from one, access on CSn is correct but no correct
access will be possible on other CS.
31 30 29 28 27 26 25 24
DLYBCT
23 22 21 20 19 18 17 16
DLYBS
15 14 13 12 11 10 9 8
SCBR
76543210
BITS CSAAT CSNAAT NCPHA CPOL
Delay Between Consecutive Transfers 32 DLYBCT
CLKSPI = ------------------------------------
Delay Before SPCK DLYBS
CLKSPI = ---------------------
SPCK Baudrate CLKSPI
SCBR = ---------------------
513
32142D–06/2013
ATUC64/128/256L3/4U
• BITS: Bits Per Transfer
The BITS field determines the number of data bits transferred. Reserved values should not be used.
• CSAAT: Chip Select Active After Transfer
1: The Peripheral Chip Select does not rise after the last transfer is achieved. It remains active until a new transfer is requested
on a different chip select.
0: The Peripheral Chip Select Line rises as soon as the last transfer is achieved.
• CSNAAT: Chip Select Not Active After Transfer (Ignored if CSAAT = 1)
0: The Peripheral Chip Select does not rise between two transfers if the TDR is reloaded before the end of the first transfer and
if the two transfers occur on the same Chip Select.
1: The Peripheral Chip Select rises systematically between each transfer performed on the same slave for a minimal duration of:
(if DLYBCT field is different from 0)
(if DLYBCT field equals 0)
• NCPHA: Clock Phase
1: Data is captured after the leading (inactive-to-active) edge of SPCK and changed on the trailing (active-to-inactive) edge of
SPCK.
0: Data is changed on the leading (inactive-to-active) edge of SPCK and captured after the trailing (active-to-inactive) edge of
SPCK.
NCPHA determines which edge of SPCK causes data to change and which edge causes data to be captured. NCPHA is used
with CPOL to produce the required clock/data relationship between master and slave devices.
• CPOL: Clock Polarity
1: The inactive state value of SPCK is logic level one.
0: The inactive state value of SPCK is logic level zero.
BITS Bits Per Transfer
0000 8
0001 9
0010 10
0011 11
0100 12
0101 13
0110 14
0111 15
1000 16
1001 4
1010 5
1011 6
1100 7
1101 Reserved
1110 Reserved
1111 Reserved
DLYBCS
CLKSPI
-----------------------
DLYBCS + 1
CLKSPI
--------------------------------
514
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ATUC64/128/256L3/4U
CPOL is used to determine the inactive state value of the serial clock (SPCK). It is used with NCPHA to produce the required
clock/data relationship between master and slave devices.
515
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ATUC64/128/256L3/4U
21.8.11 Chip Select Register 2
Name: CSR2
Access Type: Read/Write
Offset: 0x38
Reset Value: 0x00000000
• DLYBCT: Delay Between Consecutive Transfers
This field defines the delay between two consecutive transfers with the same peripheral without removing the chip select. The
delay is always inserted after each transfer and before removing the chip select if needed.
When DLYBCT equals zero, no delay between consecutive transfers is inserted and the clock keeps its duty cycle over the
character transfers.
Otherwise, the following equation determines the delay:
• DLYBS: Delay Before SPCK
This field defines the delay from NPCS valid to the first valid SPCK transition.
When DLYBS equals zero, the NPCS valid to SPCK transition is 1/2 the SPCK clock period.
Otherwise, the following equations determine the delay:
• SCBR: Serial Clock Baud Rate
In Master Mode, the SPI Interface uses a modulus counter to derive the SPCK baud rate from the CLK_SPI. The Baud rate is
selected by writing a value from 1 to 255 in the SCBR field. The following equations determine the SPCK baud rate:
Writing the SCBR field to zero is forbidden. Triggering a transfer while SCBR is zero can lead to unpredictable results.
At reset, SCBR is zero and the user has to write it to a valid value before performing the first transfer.
If a clock divider (SCBRn) field is set to one and the other SCBR fields differ from one, access on CSn is correct but no correct
access will be possible on other CS.
31 30 29 28 27 26 25 24
DLYBCT
23 22 21 20 19 18 17 16
DLYBS
15 14 13 12 11 10 9 8
SCBR
76543210
BITS CSAAT CSNAAT NCPHA CPOL
Delay Between Consecutive Transfers 32 DLYBCT
CLKSPI = ------------------------------------
Delay Before SPCK DLYBS
CLKSPI = ---------------------
SPCK Baudrate CLKSPI
SCBR = ---------------------
516
32142D–06/2013
ATUC64/128/256L3/4U
• BITS: Bits Per Transfer
The BITS field determines the number of data bits transferred. Reserved values should not be used.
• CSAAT: Chip Select Active After Transfer
1: The Peripheral Chip Select does not rise after the last transfer is achieved. It remains active until a new transfer is requested
on a different chip select.
0: The Peripheral Chip Select Line rises as soon as the last transfer is achieved.
• CSNAAT: Chip Select Not Active After Transfer (Ignored if CSAAT = 1)
0: The Peripheral Chip Select does not rise between two transfers if the TDR is reloaded before the end of the first transfer and
if the two transfers occur on the same Chip Select.
1: The Peripheral Chip Select rises systematically between each transfer performed on the same slave for a minimal duration of:
(if DLYBCT field is different from 0)
(if DLYBCT field equals 0)
• NCPHA: Clock Phase
1: Data is captured after the leading (inactive-to-active) edge of SPCK and changed on the trailing (active-to-inactive) edge of
SPCK.
0: Data is changed on the leading (inactive-to-active) edge of SPCK and captured after the trailing (active-to-inactive) edge of
SPCK.
NCPHA determines which edge of SPCK causes data to change and which edge causes data to be captured. NCPHA is used
with CPOL to produce the required clock/data relationship between master and slave devices.
• CPOL: Clock Polarity
1: The inactive state value of SPCK is logic level one.
0: The inactive state value of SPCK is logic level zero.
BITS Bits Per Transfer
0000 8
0001 9
0010 10
0011 11
0100 12
0101 13
0110 14
0111 15
1000 16
1001 4
1010 5
1011 6
1100 7
1101 Reserved
1110 Reserved
1111 Reserved
DLYBCS
CLKSPI
-----------------------
DLYBCS + 1
CLKSPI
--------------------------------
517
32142D–06/2013
ATUC64/128/256L3/4U
CPOL is used to determine the inactive state value of the serial clock (SPCK). It is used with NCPHA to produce the required
clock/data relationship between master and slave devices.
518
32142D–06/2013
ATUC64/128/256L3/4U
21.8.12 Chip Select Register 3
Name: CSR3
Access Type: Read/Write
Offset: 0x3C
Reset Value: 0x00000000
• DLYBCT: Delay Between Consecutive Transfers
This field defines the delay between two consecutive transfers with the same peripheral without removing the chip select. The
delay is always inserted after each transfer and before removing the chip select if needed.
When DLYBCT equals zero, no delay between consecutive transfers is inserted and the clock keeps its duty cycle over the
character transfers.
Otherwise, the following equation determines the delay:
• DLYBS: Delay Before SPCK
This field defines the delay from NPCS valid to the first valid SPCK transition.
When DLYBS equals zero, the NPCS valid to SPCK transition is 1/2 the SPCK clock period.
Otherwise, the following equations determine the delay:
• SCBR: Serial Clock Baud Rate
In Master Mode, the SPI Interface uses a modulus counter to derive the SPCK baud rate from the CLK_SPI. The Baud rate is
selected by writing a value from 1 to 255 in the SCBR field. The following equations determine the SPCK baud rate:
Writing the SCBR field to zero is forbidden. Triggering a transfer while SCBR is zero can lead to unpredictable results.
At reset, SCBR is zero and the user has to write it to a valid value before performing the first transfer.
If a clock divider (SCBRn) field is set to one and the other SCBR fields differ from one, access on CSn is correct but no correct
access will be possible on other CS.
31 30 29 28 27 26 25 24
DLYBCT
23 22 21 20 19 18 17 16
DLYBS
15 14 13 12 11 10 9 8
SCBR
76543210
BITS CSAAT CSNAAT NCPHA CPOL
Delay Between Consecutive Transfers 32 DLYBCT
CLKSPI = ------------------------------------
Delay Before SPCK DLYBS
CLKSPI = ---------------------
SPCK Baudrate CLKSPI
SCBR = ---------------------
519
32142D–06/2013
ATUC64/128/256L3/4U
• BITS: Bits Per Transfer
The BITS field determines the number of data bits transferred. Reserved values should not be used.
• CSAAT: Chip Select Active After Transfer
1: The Peripheral Chip Select does not rise after the last transfer is achieved. It remains active until a new transfer is requested
on a different chip select.
0: The Peripheral Chip Select Line rises as soon as the last transfer is achieved.
• CSNAAT: Chip Select Not Active After Transfer (Ignored if CSAAT = 1)
0: The Peripheral Chip Select does not rise between two transfers if the TDR is reloaded before the end of the first transfer and
if the two transfers occur on the same Chip Select.
1: The Peripheral Chip Select rises systematically between each transfer performed on the same slave for a minimal duration of:
(if DLYBCT field is different from 0)
(if DLYBCT field equals 0)
• NCPHA: Clock Phase
1: Data is captured after the leading (inactive-to-active) edge of SPCK and changed on the trailing (active-to-inactive) edge of
SPCK.
0: Data is changed on the leading (inactive-to-active) edge of SPCK and captured after the trailing (active-to-inactive) edge of
SPCK.
NCPHA determines which edge of SPCK causes data to change and which edge causes data to be captured. NCPHA is used
with CPOL to produce the required clock/data relationship between master and slave devices.
• CPOL: Clock Polarity
1: The inactive state value of SPCK is logic level one.
0: The inactive state value of SPCK is logic level zero.
BITS Bits Per Transfer
0000 8
0001 9
0010 10
0011 11
0100 12
0101 13
0110 14
0111 15
1000 16
1001 4
1010 5
1011 6
1100 7
1101 Reserved
1110 Reserved
1111 Reserved
DLYBCS
CLKSPI
-----------------------
DLYBCS + 1
CLKSPI
--------------------------------
520
32142D–06/2013
ATUC64/128/256L3/4U
CPOL is used to determine the inactive state value of the serial clock (SPCK). It is used with NCPHA to produce the required
clock/data relationship between master and slave devices.
521
32142D–06/2013
ATUC64/128/256L3/4U
21.8.13 Write Protection Control Register
Register Name: WPCR
Access Type: Read-write
Offset: 0xE4
Reset Value: 0x00000000
• SPIWPKEY: SPI Write Protection Key Password
If a value is written in SPIWPEN, the value is taken into account only if SPIWPKEY is written with “SPI” (SPI written in ASCII
Code, i.e. 0x535049 in hexadecimal).
• SPIWPEN: SPI Write Protection Enable
1: The Write Protection is Enabled
0: The Write Protection is Disabled
31 30 29 28 27 26 25 24
SPIWPKEY[23:16]
23 22 21 20 19 18 17 16
SPIWPKEY[15:8]
15 14 13 12 11 10 9 8
SPIWPKEY[7:0]
76543210
- - - - - - - SPIWPEN
522
32142D–06/2013
ATUC64/128/256L3/4U
21.8.14 Write Protection Status Register
Register Name: WPSR
Access Type: Read-only
Offset: 0xE8
Reset Value: 0x00000000
• SPIWPVSRC: SPI Write Protection Violation Source
This Field indicates the Peripheral Bus Offset of the register concerned by the violation (MR or CSRx)
• SPIWPVS: SPI Write Protection Violation Status
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SPIWPVSRC
76543210
- - - - - SPIWPVS
SPIWPVS value Violation Type
1 The Write Protection has blocked a Write access to a protected register (since the last read).
2 Software Reset has been performed while Write Protection was enabled (since the last read
or since the last write access on MR, IER, IDR or CSRx).
3 Both Write Protection violation and software reset with Write Protection enabled have
occurred since the last read.
4 Write accesses have been detected on MR (while a chip select was active) or on CSRi (while
the Chip Select “i” was active) since the last read.
5
The Write Protection has blocked a Write access to a protected register and write accesses
have been detected on MR (while a chip select was active) or on CSRi (while the Chip Select
“i” was active) since the last read.
6
Software Reset has been performed while Write Protection was enabled (since the last read
or since the last write access on MR, IER, IDR or CSRx) and some write accesses have been
detected on MR (while a chip select was active) or on CSRi (while the Chip Select “i” was
active) since the last read.
7
- The Write Protection has blocked a Write access to a protected register.
and
- Software Reset has been performed while Write Protection was enabled.
and
- Write accesses have been detected on MR (while a chip select was active) or on CSRi
(while the Chip Select “i” was active) since the last read.
523
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ATUC64/128/256L3/4U
21.8.15 Features Register
Register Name: FEATURES
Access Type: Read-only
Offset: 0xF8
Reset Value: –
• SWIMPL: Spurious Write Protection Implemented
0: Spurious write protection is not implemented.
1: Spurious write protection is implemented.
• FIFORIMPL: FIFO in Reception Implemented
0: FIFO in reception is not implemented.
1: FIFO in reception is implemented.
• BRPBHSB: Bridge Type is PB to HSB
0: Bridge type is not PB to HSB.
1: Bridge type is PB to HSB.
• CSNAATIMPL: CSNAAT Features Implemented
0: CSNAAT (Chip select not active after transfer) features are not implemented.
1: CSNAAT features are implemented.
• EXTDEC: External Decoder True
0: External decoder capability is not implemented.
1: External decoder capability is implemented.
• LENNCONF: Character Length if not Configurable
If the character length is not configurable, this field specifies the fixed character length.
• LENCONF: Character Length Configurable
0: The character length is not configurable.
1: The character length is configurable.
• PHZNCONF: Phase is Zero if Phase not Configurable
0: If phase is not configurable, phase is non-zero.
1: If phase is not configurable, phase is zero.
• PHCONF: Phase Configurable
0: Phase is not configurable.
1: Phase is configurable.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - SWIMPL FIFORIMPL BRPBHSB CSNAATIMPL EXTDEC
15 14 13 12 11 10 9 8
LENNCONF LENCONF
76543210
PHZNCONF PHCONF PPNCONF PCONF NCS
524
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ATUC64/128/256L3/4U
• PPNCONF: Polarity Positive if Polarity not Configurable
0: If polarity is not configurable, polarity is negative.
1: If polarity is not configurable, polarity is positive.
• PCONF: Polarity Configurable
0: Polarity is not configurable.
1: Polarity is configurable.
• NCS: Number of Chip Selects
This field indicates the number of chip selects implemented.
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21.8.16 Version Register
Register Name: VERSION
Access Type: Read-only
Offset: 0xFC
Reset Value: –
• MFN
Reserved. No functionality associated.
• VERSION
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - MFN
15 14 13 12 11 10 9 8
VERSION[11:8]
76543210
VERSION[7:0]
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21.9 Module Configuration
The specific configuration for each SPI instance is listed in the following tables.The module bus
clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 21-4. SPI Clock Name
Module Name Clock Name Description
SPI CLK_SPI Clock for the SPI bus interface
Table 21-5.
Register Reset Value
FEATURES 0x001F0154
VERSION 0x00000211
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22. Two-wire Master Interface (TWIM)
Rev.: 1.1.0.1
22.1 Features
• Compatible with I²C standard
– Multi-master support
– Transfer speeds of 100 and 400 kbit/s
– 7- and 10-bit and General Call addressing
• Compatible with SMBus standard
– Hardware Packet Error Checking (CRC) generation and verification with ACK control
– SMBus ALERT interface
– 25 ms clock low timeout delay
– 10 ms master cumulative clock low extend time
– 25 ms slave cumulative clock low extend time
• Compatible with PMBus
• Compatible with Atmel Two-wire Interface Serial Memories
• DMA interface for reducing CPU load
• Arbitrary transfer lengths, including 0 data bytes
• Optional clock stretching if transmit or receive buffers not ready for data transfer
22.2 Overview
The Atmel Two-wire Master Interface (TWIM) interconnects components on a unique two-wire
bus, made up of one clock line and one data line with speeds of up to 400 kbit/s, based on a
byte-oriented transfer format. It can be used with any Atmel Two-wire Interface bus serial
EEPROM and I²C compatible device such as a real time clock (RTC), dot matrix/graphic LCD
controller, and temperature sensor, to name a few. The TWIM is always a bus master and can
transfer sequential or single bytes. Multiple master capability is supported. Arbitration of the bus
is performed internally and relinquishes the bus automatically if the bus arbitration is lost.
A configurable baud rate generator permits the output data rate to be adapted to a wide range of
core clock frequencies.Table 22-1 lists the compatibility level of the Atmel Two-wire Interface in
Master Mode and a full I²C compatible device.
Note: 1. START + b000000001 + Ack + Sr
Table 22-1. Atmel TWIM Compatibility with I²C Standard
I²C Standard Atmel TWIM
Standard-mode (100 kbit/s) Supported
Fast-mode (400 kbit/s) Supported
Fast-mode Plus (1 Mbit/s) Supported
7- or 10-bits Slave Addressing Supported
START BYTE(1) Not Supported
Repeated Start (Sr) Condition Supported
ACK and NACK Management Supported
Slope Control and Input Filtering (Fast mode) Supported
Clock Stretching Supported
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Table 22-2 lists the compatibility level of the Atmel Two-wire Master Interface and a full SMBus
compatible master.
22.3 List of Abbreviations
22.4 Block Diagram
Figure 22-1. Block Diagram
Table 22-2. Atmel TWIM Compatibility with SMBus Standard
SMBus Standard Atmel TWIM
Bus Timeouts Supported
Address Resolution Protocol Supported
Alert Supported
Host Functionality Supported
Packet Error Checking Supported
Table 22-3. Abbreviations
Abbreviation Description
TWI Two-wire Interface
A Acknowledge
NA Non Acknowledge
P Stop
S Start
Sr Repeated Start
SADR Slave Address
ADR Any address except SADR
R Read
W Write
Peripheral
Bus Bridge
Two-wire
Interface
I/O Controller
TWCK
TWD
INTC
TWI Interrupt
Power
Manager
CLK_TWIM
TWALM
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22.5 Application Block Diagram
Figure 22-2. Application Block Diagram
22.6 I/O Lines Description
22.7 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
22.7.1 I/O Lines
TWD and TWCK are bidirectional lines, connected to a positive supply voltage via a current
source or pull-up resistor (see Figure 22-4 on page 531). When the bus is free, both lines are
high. The output stages of devices connected to the bus must have an open-drain or open-collector
to perform the wired-AND function.
TWALM is used to implement the optional SMBus SMBALERT signal.
The TWALM, TWD, and TWCK pins may be multiplexed with I/O Controller lines. To enable the
TWIM, the user must perform the following steps:
• Program the I/O Controller to:
– Dedicate TWD, TWCK, and optionally TWALM as peripheral lines.
– Define TWD, TWCK, and optionally TWALM as open-drain.
22.7.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the TWIM, the TWIM will stop functioning
and resume operation after the system wakes up from sleep mode.
TWI
Master
TWD
TWCK
Atmel TWI
serial EEPROM I
2
C RTC I
2
C LCD
controller
I
2
C temp
sensor
Slave 2 Slave 3 Slave 4
VDD
Rp: pull-up value as given by the I2C Standard
TWALM
Slave 1
Rp Rp Rp
Table 22-4. I/O Lines Description
Pin Name Pin Description Type
TWD Two-wire Serial Data Input/Output
TWCK Two-wire Serial Clock Input/Output
TWALM SMBus SMBALERT Input/Output
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22.7.3 Clocks
The clock for the TWIM bus interface (CLK_TWIM) is generated by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable
the TWIM before disabling the clock, to avoid freezing the TWIM in an undefined state.
22.7.4 DMA
The TWIM DMA handshake interface is connected to the Peripheral DMA Controller. Using the
TWIM DMA functionality requires the Peripheral DMA Controller to be programmed after setting
up the TWIM.
22.7.5 Interrupts
The TWIM interrupt request lines are connected to the interrupt controller. Using the TWIM interrupts
requires the interrupt controller to be programmed first.
22.7.6 Debug Operation
When an external debugger forces the CPU into debug mode, the TWIM continues normal operation.
If the TWIM is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
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22.8 Functional Description
22.8.1 Transfer Format
The data put on the TWD line must be 8 bits long. Data is transferred MSB first; each byte must
be followed by an acknowledgement. The number of bytes per transfer is unlimited (see Figure
22-4).
Each transfer begins with a START condition and terminates with a STOP condition (see Figure
22-4).
• A high-to-low transition on the TWD line while TWCK is high defines the START condition.
• A low-to-high transition on the TWD line while TWCK is high defines a STOP condition.
Figure 22-3. START and STOP Conditions
Figure 22-4. Transfer Format
22.8.2 Operation
The TWIM has two modes of operation:
• Master transmitter mode
• Master receiver mode
The master is the device which starts and stops a transfer and generates the TWCK clock.
These modes are described in the following chapters.
TWD
TWCK
Start Stop
TWD
TWCK
Start Address R/W Ack Data Ack Data Ack Stop
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22.8.2.1 Clock Generation
The Clock Waveform Generator Register (CWGR) is used to control the waveform of the TWCK
clock. CWGR must be written so that the desired TWI bus timings are generated. CWGR
describes bus timings as a function of cycles of a prescaled clock. The clock prescaling can be
selected through the Clock Prescaler field in CWGR (CWGR.EXP).
CWGR has the following fields:
LOW: Prescaled clock cycles in clock low count. Used to time TLOW and TBUF.
HIGH: Prescaled clock cycles in clock high count. Used to time THIGH.
STASTO: Prescaled clock cycles in clock high count. Used to time THD_STA, TSU_STA, TSU_STO.
DATA: Prescaled clock cycles for data setup and hold count. Used to time THD_DAT, TSU_DAT.
EXP: Specifies the clock prescaler setting.
Note that the total clock low time generated is the sum of THD_DAT + TSU_DAT + TLOW.
Any slave or other bus master taking part in the transfer may extend the TWCK low period at any
time.
The TWIM hardware monitors the state of the TWCK line as required by the I²C specification.
The clock generation counters are started when a high/low level is detected on the TWCK line,
not when the TWIM hardware releases/drives the TWCK line. This means that the CWGR settings
alone do not determine the TWCK frequency. The CWGR settings determine the clock low
time and the clock high time, but the TWCK rise and fall times are determined by the external circuitry
(capacitive load, etc.).
Figure 22-5. Bus Timing Diagram
f
PRESCALER
f
CLK_TWIM
2 EXP 1 + = -------------------------
S t
HD:STA
t LOW
t
SU:DAT
t HIGH
t
HD:DAT
t LOW
P
t
SU:STO
Sr
t
SU:STA
t
SU:DAT
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22.8.2.2 Setting up and Performing a Transfer
Operation of the TWIM is mainly controlled by the Control Register (CR) and the Command Register
(CMDR). TWIM status is provided in the Status Register (SR). The following list presents
the main steps in a typical communication:
1. Before any transfers can be performed, bus timings must be configured by writing to the
Clock Waveform Generator Register (CWGR). If operating in SMBus mode, the SMBus
Timing Register (SMBTR) register must also be configured.
2. If the Peripheral DMA Controller is to be used for the transfers, it must be set up.
3. CMDR or NCMDR must be written with a value describing the transfer to be performed.
The interrupt system can be set up to give interrupt requests on specific events or error conditions
in the SR, for example when the transfer is complete or if arbitration is lost. The Interrupt
Enable Register (IER) and Interrupt Disable Register (IDR) can be written to specify which bits in
the SR will generate interrupt requests.
The SR.BUSFREE bit is set when activity is completed on the two-wire bus. The SR.CRDY bit is
set when CMDR and/or NCMDR is ready to receive one or more commands.
The controller will refuse to start a new transfer while ANAK, DNAK, or ARBLST in the Status
Register (SR) is one. This is necessary to avoid a race when the software issues a continuation
of the current transfer at the same time as one of these errors happen. Also, if ANAK or DNAK
occurs, a STOP condition is sent automatically. The user will have to restart the transmission by
clearing the error bits in SR after resolving the cause for the NACK.
After a data or address NACK from the slave, a STOP will be transmitted automatically. Note
that the VALID bit in CMDR is NOT cleared in this case. If this transfer is to be discarded, the
VALID bit can be cleared manually allowing any command in NCMDR to be copied into CMDR.
When a data or address NACK is returned by the slave while the master is transmitting, it is possible
that new data has already been written to the THR register. This data will be transferred out
as the first data byte of the next transfer. If this behavior is to be avoided, the safest approach is
to perform a software reset of the TWIM.
22.8.3 Master Transmitter Mode
A START condition is transmitted and master transmitter mode is initiated when the bus is free
and CMDR has been written with START=1 and READ=0. START and SADR+W will then be
transmitted. During the address acknowledge clock pulse (9th pulse), the master releases the
data line (HIGH), enabling the slave to pull it down in order to acknowledge the address. The
master polls the data line during this clock pulse and sets the Address Not Acknowledged bit
(ANAK) in the Status Register if no slave acknowledges the address.
After the address phase, the following is repeated:
while (NBYTES>0)
1. Wait until THR contains a valid data byte, stretching low period of TWCK. SR.TXRDY
indicates the state of THR. Software or the Peripheral DMA Controller must write the
data byte to THR.
2. Transmit this data byte
3. Decrement NBYTES
4. If (NBYTES==0) and STOP=1, transmit STOP condition
Writing CMDR with START=STOP=1 and NBYTES=0 will generate a transmission with no data
bytes, ie START, SADR+W, STOP.
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TWI transfers require the slave to acknowledge each received data byte. During the acknowledge
clock pulse (9th pulse), the master releases the data line (HIGH), enabling the slave to pull
it down in order to generate the acknowledge. The master polls the data line during this clock
pulse and sets the Data Acknowledge bit (DNACK) in the Status Register if the slave does not
acknowledge the data byte. As with the other status bits, an interrupt can be generated if
enabled in the Interrupt Enable Register (IER).
TXRDY is used as Transmit Ready for the Peripheral DMA Controller transmit channel.
The end of a command is marked when the TWIM sets the SR.CCOMP bit. See Figure 22-6 and
Figure 22-7.
Figure 22-6. Master Write with One Data Byte
Figure 22-7. Master Write with Multiple Data Bytes
22.8.4 Master Receiver Mode
A START condition is transmitted and master receiver mode is initiated when the bus is free and
CMDR has been written with START=1 and READ=1. START and SADR+R will then be transmitted.
During the address acknowledge clock pulse (9th pulse), the master releases the data
line (HIGH), enabling the slave to pull it down in order to acknowledge the address. The master
polls the data line during this clock pulse and sets the Address Not Acknowledged bit (ANAK) in
the Status Register if no slave acknowledges the address.
After the address phase, the following is repeated:
while (NBYTES>0)
TWD
SR.IDLE
TXRDY
Write THR (DATA)
NBYTES set to 1
STOP sent automatically
(ACK received and NBYTES=0)
S DADR W A DATA A P
TWD
SR.IDLE
TXRDY
Write THR
(DATAn)
NBYTES set to n
STOP sent automatically
(ACK received and NBYTES=0)
S DADR W A DATAn A DATAn+5 A A DATAn+m P
Write THR
(DATAn+1)
Write THR
(DATAn+m)
Last data sent
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1. Wait until RHR is empty, stretching low period of TWCK. SR.RXRDY indicates the state
of RHR. Software or the Peripheral DMA Controller must read any data byte present in
RHR.
2. Release TWCK generating a clock that the slave uses to transmit a data byte.
3. Place the received data byte in RHR, set RXRDY.
4. If NBYTES=0, generate a NAK after the data byte, otherwise generate an ACK.
5. Decrement NBYTES
6. If (NBYTES==0) and STOP=1, transmit STOP condition.
Writing CMDR with START=STOP=1 and NBYTES=0 will generate a transmission with no data
bytes, ie START, DADR+R, STOP
The TWI transfers require the master to acknowledge each received data byte. During the
acknowledge clock pulse (9th pulse), the slave releases the data line (HIGH), enabling the master
to pull it down in order to generate the acknowledge. All data bytes except the last are
acknowledged by the master. Not acknowledging the last byte informs the slave that the transfer
is finished.
RXRDY is used as Receive Ready for the Peripheral DMA Controller receive channel.
Figure 22-8. Master Read with One Data Byte
Figure 22-9. Master Read with Multiple Data Bytes
TWD
SR.IDLE
RXRDY
Write START &
STOP bit
NBYTES set to 1
Read RHR
S DADR R A DATA N P
TWD
SR.IDLE
RXRDY
Write START +
STOP bit
NBYTES set to m
S DADR R A DATAn A DATAn+m-1 A N DATAn+m P
Read RHR
DATAn
DATAn+1
Read RHR
DATAn+m-2
Read RHR
DATAn+m-1
Read RHR
DATAn+m
Send STOP
When NBYTES=0
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22.8.5 Using the Peripheral DMA Controller
The use of the Peripheral DMA Controller significantly reduces the CPU load. The user can set
up ring buffers for the Peripheral DMA Controller, containing data to transmit or free buffer space
to place received data.
To assure correct behavior, respect the following programming sequences:
22.8.5.1 Data Transmit with the Peripheral DMA Controller
1. Initialize the transmit Peripheral DMA Controller (memory pointers, size, etc.).
2. Configure the TWIM (ADR, NBYTES, etc.).
3. Start the transfer by enabling the Peripheral DMA Controller to transmit.
4. Wait for the Peripheral DMA Controller end-of-transmit flag.
5. Disable the Peripheral DMA Controller.
22.8.5.2 Data Receive with the Peripheral DMA Controller
1. Initialize the receive Peripheral DMA Controller (memory pointers, size, etc.).
2. Configure the TWIM (ADR, NBYTES, etc.).
3. Start the transfer by enabling the Peripheral DMA Controller to receive.
4. Wait for the Peripheral DMA Controller end-of-receive flag.
5. Disable the Peripheral DMA Controller.
22.8.6 Multi-master Mode
More than one master may access the bus at the same time without data corruption by using
arbitration.
Arbitration starts as soon as two or more masters place information on the bus at the same time,
and stops (arbitration is lost) for the master that intends to send a logical one while the other
master sends a logical zero.
As soon as arbitration is lost by a master, it stops sending data and listens to the bus in order to
detect a STOP. The SR.ARBLST flag will be set. When the STOP is detected, the master who
lost arbitration may reinitiate the data transfer.
Arbitration is illustrated in Figure 22-11.
If the user starts a transfer and if the bus is busy, the TWIM automatically waits for a STOP condition
on the bus before initiating the transfer (see Figure 22-10).
Note: The state of the bus (busy or free) is not indicated in the user interface.
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Figure 22-10. User Sends Data While the Bus is Busy
Figure 22-11. Arbitration Cases
22.8.7 Combined Transfers
CMDR and NCMDR may be used to generate longer sequences of connected transfers, since
generation of START and/or STOP conditions is programmable on a per-command basis.
Writing NCMDR with START=1 when the previous transfer was written with STOP=0 will cause
a REPEATED START on the bus. The ability to generate such connected transfers allows arbitrary
transfer lengths, since it is legal to write CMDR with both START=0 and STOP=0. If this is
done in master receiver mode, the CMDR.ACKLAST bit must also be controlled.
TWCK
TWD DATA sent by a master
STOP sent by the master START sent by the TWI
DATA sent by the TWI
Bus is busy
Bus is free
A transfer is programmed
(DADR + W + START + Write THR) Transfer is initiated
TWI DATA transfer Transfer is kept
Bus is considered as free
TWCK
Bus is busy Bus is free
A transfer is programmed
(DADR + W + START + Write THR) Transfer is initiated
TWI DATA transfer Transfer is kept
Bus is considered as free
Data from a Master
Data from TWI S 0
S 0 0
1
1
1
ARBLST
S 0
S 0 0
1
1
1
TWD S 1 0 0
1 1
1 1
Arbitration is lost
TWI stops sending data
P
P S 1 0 0
1 1
Data from the master 1 1 Data from the TWI
Arbitration is lost
The master stops sending data
Transfer is stopped
Transfer is programmed again
(DADR + W + START + Write THR)
TWCK
TWD
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As for single data transfers, the TXRDY and RXRDY bits in the Status Register indicates when
data to transmit can be written to THR, or when received data can be read from RHR. Transfer
of data to THR and from RHR can also be done automatically by DMA, see Section 22.8.5
22.8.7.1 Write Followed by Write
Consider the following transfer:
START, DADR+W, DATA+A, DATA+A, REPSTART, DADR+W, DATA+A, DATA+A, STOP.
To generate this transfer:
1. Write CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=0.
2. Write NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=0.
3. Wait until SR.TXRDY==1, then write first data byte to transfer to THR.
4. Wait until SR.TXRDY==1, then write second data byte to transfer to THR.
5. Wait until SR.TXRDY==1, then write third data byte to transfer to THR.
6. Wait until SR.TXRDY==1, then write fourth data byte to transfer to THR.
22.8.7.2 Read Followed by Read
Consider the following transfer:
START, DADR+R, DATA+A, DATA+NA, REPSTART, DADR+R, DATA+A, DATA+NA, STOP.
To generate this transfer:
1. Write CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=1.
2. Write NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=1.
3. Wait until SR.RXRDY==1, then read first data byte received from RHR.
4. Wait until SR.RXRDY==1, then read second data byte received from RHR.
5. Wait until SR.RXRDY==1, then read third data byte received from RHR.
6. Wait until SR.RXRDY==1, then read fourth data byte received from RHR.
If combining several transfers, without any STOP or REPEATED START between them, remember
to write a one to the ACKLAST bit in CMDR to keep from ending each of the partial transfers
with a NACK.
22.8.7.3 Write Followed by Read
Consider the following transfer:
START, DADR+W, DATA+A, DATA+A, REPSTART, DADR+R, DATA+A, DATA+NA, STOP.
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Figure 22-12. Combining a Write and Read Transfer
To generate this transfer:
1. Write CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=0.
2. Write NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=1.
3. Wait until SR.TXRDY==1, then write first data byte to transfer to THR.
4. Wait until SR.TXRDY==1, then write second data byte to transfer to THR.
5. Wait until SR.RXRDY==1, then read first data byte received from RHR.
6. Wait until SR.RXRDY==1, then read second data byte received from RHR.
22.8.7.4 Read Followed by Write
Consider the following transfer:
START, DADR+R, DATA+A, DATA+NA, REPSTART, DADR+W, DATA+A, DATA+A, STOP.
Figure 22-13. Combining a Read and Write Transfer
To generate this transfer:
1. Write CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=1.
2. Write NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=0.
3. Wait until SR.RXRDY==1, then read first data byte received from RHR.
4. Wait until SR.RXRDY==1, then read second data byte received from RHR.
5. Wait until SR.TXRDY==1, then write first data byte to transfer to THR.
6. Wait until SR.TXRDY==1, then write second data byte to transfer to THR.
TWD
SR.IDLE
TXRDY
S DADR W A DATA0 A DATA1 NA Sr DADR R A DATA2 A DATA3 A P
THR DATA0 DATA1
RXRDY
1
RHR DATA2 DATA3
TWD
SR.IDLE
TXRDY
S SADR R A DATA0 A DATA1 Sr DADR W A DATA2 A DATA3 NA P
THR DATA2
RXRDY
RHR DATA0 DATA3
A
1
2
DATA3
Read
TWI_RHR
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22.8.8 Ten Bit Addressing
Writing a one to CMDR.TENBIT enables 10-bit addressing in hardware. Performing transfers
with 10-bit addressing is similar to transfers with 7-bit addresses, except that bits 9:7 of
CMDR.SADR must be written appropriately.
In Figure 22-14 and Figure 22-15, the grey boxes represent signals driven by the master, the
white boxes are driven by the slave.
22.8.8.1 Master Transmitter
To perform a master transmitter transfer:
1. Write CMDR with TENBIT=1, REPSAME=0, READ=0, START=1, STOP=1 and the
desired address and NBYTES value.
Figure 22-14. A Write Transfer with 10-bit Addressing
22.8.8.2 Master Receiver
When using master receiver mode with 10-bit addressing, CMDR.REPSAME must also be controlled.
CMDR.REPSAME must be written to one when the address phase of the transfer should
consist of only 1 address byte (the 11110xx byte) and not 2 address bytes. The I²C standard
specifies that such addressing is required when addressing a slave for reads using 10-bit
addressing.
To perform a master receiver transfer:
1. Write CMDR with TENBIT=1, REPSAME=0, READ=0, START=1, STOP=0,
NBYTES=0 and the desired address.
2. Write NCMDR with TENBIT=1, REPSAME=1, READ=1, START=1, STOP=1 and the
desired address and NBYTES value.
Figure 22-15. A Read Transfer with 10-bit Addressing
22.8.9 SMBus Mode
SMBus mode is enabled and disabled by writing to the SMEN and SMDIS bits in CR. SMBus
mode operation is similar to I²C operation with the following exceptions:
• Only 7-bit addressing can be used.
• The SMBus standard describes a set of timeout values to ensure progress and throughput on
the bus. These timeout values must be written into SMBTR.
• Transmissions can optionally include a CRC byte, called Packet Error Check (PEC).
• A dedicated bus line, SMBALERT, allows a slave to get a master’s attention.
• A set of addresses have been reserved for protocol handling, such as Alert Response
Address (ARA) and Host Header (HH) Address.
S SLAVE ADDRESS
1st 7 bits RW A1 A2 DATA A P SLAVE ADDRESS
2nd byte DATA AA
11110XX0
S SLAVE ADDRESS
1st 7 bits RW A1 A2 DATA A P SLAVE ADDRESS
2nd byte DATA A
11110XX0
Sr SLAVE ADDRESS
1st 7 bits RW A3
11110XX1
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22.8.9.1 Packet Error Checking
Each SMBus transfer can optionally end with a CRC byte, called the PEC byte. Writing a one to
CMDR.PECEN enables automatic PEC handling in the current transfer. Transfers with and without
PEC can freely be intermixed in the same system, since some slaves may not support PEC.
The PEC LFSR is always updated on every bit transmitted or received, so that PEC handling on
combined transfers will be correct.
In master transmitter mode, the master calculates a PEC value and transmits it to the slave after
all data bytes have been transmitted. Upon reception of this PEC byte, the slave will compare it
to the PEC value it has computed itself. If the values match, the data was received correctly, and
the slave will return an ACK to the master. If the PEC values differ, data was corrupted, and the
slave will return a NACK value. The DNAK bit in SR reflects the state of the last received
ACK/NACK value. Some slaves may not be able to check the received PEC in time to return a
NACK if an error occurred. In this case, the slave should always return an ACK after the PEC
byte, and some other mechanism must be implemented to verify that the transmission was
received correctly.
In master receiver mode, the slave calculates a PEC value and transmits it to the master after all
data bytes have been transmitted. Upon reception of this PEC byte, the master will compare it to
the PEC value it has computed itself. If the values match, the data was received correctly. If the
PEC values differ, data was corrupted, and SR.PECERR is set. In master receiver mode, the
PEC byte is always followed by a NACK transmitted by the master, since it is the last byte in the
transfer.
The PEC byte is automatically inserted in a master transmitter transmission if PEC is enabled
when NBYTES reaches zero. The PEC byte is identified in a master receiver transmission if
PEC is enabled when NBYTES reaches zero. NBYTES must therefore be written with the total
number of data bytes in the transmission, including the PEC byte.
In combined transfers, the PECEN bit should only be written to one in the last of the combined
transfers. Consider the following transfer:
S, ADR+W, COMMAND_BYTE, ACK, SR, ADR+R, DATA_BYTE, ACK, PEC_BYTE, NACK, P
This transfer is generated by writing two commands to the command registers. The first command
is a write with NBYTES=1 and PECEN=0, and the second is a read with NBYTES=2 and
PECEN=1.
Writing a one to the STOP bit in CR will place a STOP condition on the bus after the current
byte. No PEC byte will be sent in this case.
22.8.9.2 Timeouts
The TLOWS and TLOWM fields in SMBTR configure the SMBus timeout values. If a timeout
occurs, the master will transmit a STOP condition and leave the bus. The SR.TOUT bit is set.
22.8.9.3 SMBus ALERT Signal
A slave can get the master’s attention by pulling the TWALM line low. The TWIM will then set the
SR.SMBALERT bit. This can be set up to trigger an interrupt, and software can then take the
appropriate action, as defined in the SMBus standard.
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22.8.10 Identifying Bus Events
This chapter lists the different bus events, and how they affect bits in the TWIM registers. This is
intended to help writing drivers for the TWIM.
Table 22-5. Bus Events
Event Effect
Master transmitter has sent
a data byte SR.THR is cleared.
Master receiver has
received a data byte SR.RHR is set.
Start+Sadr sent, no ack
received from slave
SR.ANAK is set.
SR.CCOMP not set.
CMDR.VALID remains set.
STOP automatically transmitted on bus.
Data byte sent to slave, no
ack received from slave
SR.DNAK is set.
SR.CCOMP not set.
CMDR.VALID remains set.
STOP automatically transmitted on bus.
Arbitration lost
SR.ARBLST is set.
SR.CCOMP not set.
CMDR.VALID remains set.
TWCK and TWD immediately released to a pulled-up state.
SMBus Alert received SR.SMBALERT is set.
SMBus timeout received
SR.SMBTOUT is set.
SR.CCOMP not set.
CMDR.VALID remains set.
STOP automatically transmitted on bus.
Master transmitter receives
SMBus PEC Error
SR.DNAK is set.
SR.CCOMP not set.
CMDR.VALID remains set.
STOP automatically transmitted on bus.
Master receiver discovers
SMBus PEC Error
SR.PECERR is set.
SR.CCOMP not set.
CMDR.VALID remains set.
STOP automatically transmitted on bus.
CR.STOP is written by user
SR.STOP is set.
SR.CCOMP set.
CMDR.VALID remains set.
STOP transmitted on bus after current byte transfer has finished.
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22.9 User Interface
Note: 1. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 22-6. TWIM Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Write-only 0x00000000
0x04 Clock Waveform Generator Register CWGR Read/Write 0x00000000
0x08 SMBus Timing Register SMBTR Read/Write 0x00000000
0x0C Command Register CMDR Read/Write 0x00000000
0x10 Next Command Register NCMDR Read/Write 0x00000000
0x14 Receive Holding Register RHR Read-only 0x00000000
0x18 Transmit Holding Register THR Write-only 0x00000000
0x1C Status Register SR Read-only 0x00000002
0x20 Interrupt Enable Register IER Write-only 0x00000000
0x24 Interrupt Disable Register IDR Write-only 0x00000000
0x28 Interrupt Mask Register IMR Read-only 0x00000000
0x2C Status Clear Register SCR Write-only 0x00000000
0x30 Parameter Register PR Read-only -(1)
0x34 Version Register VR Read-only -(1)
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22.9.1 Control Register
Name: CR
Access Type: Write-only
Offset: 0x00
Reset Value: 0x00000000
• STOP: Stop the Current Transfer
Writing a one to this bit terminates the current transfer, sending a STOP condition after the shifter has become idle. If there are
additional pending transfers, they will have to be explicitly restarted by software after the STOP condition has been successfully
sent.
Writing a zero to this bit has no effect.
• SWRST: Software Reset
If the TWIM master interface is enabled, writing a one to this bit resets the TWIM. All transfers are halted immediately, possibly
violating the bus semantics.
If the TWIM master interface is not enabled, it must first be enabled before writing a one to this bit.
Writing a zero to this bit has no effect.
• SMDIS: SMBus Disable
Writing a one to this bit disables SMBus mode.
Writing a zero to this bit has no effect.
• SMEN: SMBus Enable
Writing a one to this bit enables SMBus mode.
Writing a zero to this bit has no effect.
• MDIS: Master Disable
Writing a one to this bit disables the master interface.
Writing a zero to this bit has no effect.
• MEN: Master Enable
Writing a one to this bit enables the master interface.
Writing a zero to this bit has no effect.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - - STOP
76543210
SWRST - SMDIS SMEN - - MDIS MEN
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22.9.2 Clock Waveform Generator Register
Name: CWGR
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• EXP: Clock Prescaler
Used to specify how to prescale the TWCK clock. Counters are prescaled according to the following formula
• DATA: Data Setup and Hold Cycles
Clock cycles for data setup and hold count. Prescaled by CWGR.EXP. Used to time THD_DAT, TSU_DAT.
• STASTO: START and STOP Cycles
Clock cycles in clock high count. Prescaled by CWGR.EXP. Used to time THD_STA, TSU_STA, TSU_STO
• HIGH: Clock High Cycles
Clock cycles in clock high count. Prescaled by CWGR.EXP. Used to time THIGH.
• LOW: Clock Low Cycles
Clock cycles in clock low count. Prescaled by CWGR.EXP. Used to time TLOW, TBUF.
31 30 29 28 27 26 25 24
- EXP DATA
23 22 21 20 19 18 17 16
STASTO
15 14 13 12 11 10 9 8
HIGH
76543210
LOW
f
PRESCALER
f
CLK_TWIM
2 EXP 1 + = -------------------------
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22.9.3 SMBus Timing Register
Name: SMBTR
Access Type: Read/Write
Offset: 0x08
Reset Value: 0x00000000
• EXP: SMBus Timeout Clock Prescaler
Used to specify how to prescale the TIM and TLOWM counters in SMBTR. Counters are prescaled according to the following
formula
• THMAX: Clock High Maximum Cycles
Clock cycles in clock high maximum count. Prescaled by SMBTR.EXP. Used for bus free detection. Used to time THIGH:MAX.
NOTE: Uses the prescaler specified by CWGR, NOT the prescaler specified by SMBTR.
• TLOWM: Master Clock Stretch Maximum Cycles
Clock cycles in master maximum clock stretch count. Prescaled by SMBTR.EXP. Used to time TLOW:MEXT
• TLOWS: Slave Clock Stretch Maximum Cycles
Clock cycles in slave maximum clock stretch count. Prescaled by SMBTR.EXP. Used to time TLOW:SEXT.
31 30 29 28 27 26 25 24
EXP - - - -
23 22 21 20 19 18 17 16
THMAX
15 14 13 12 11 10 9 8
TLOWM
76543210
TLOWS
f
prescaled SMBus
f
CLKTWIM
2 EXP + 1 = ------------------------
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22.9.4 Command Register
Name: CMDR
Access Type: Read/Write
Offset: 0x0C
Reset Value: 0x00000000
• ACKLAST: ACK Last Master RX Byte
0: Causes the last byte in master receive mode (when NBYTES has reached 0) to be NACKed. This is the standard way of
ending a master receiver transfer.
1: Causes the last byte in master receive mode (when NBYTES has reached 0) to be ACKed. Used for performing linked
transfers in master receiver mode with no STOP or REPEATED START between the subtransfers. This is needed when more
than 255 bytes are to be received in one single transmission.
• PECEN: Packet Error Checking Enable
0: Causes the transfer not to use PEC byte verification. The PEC LFSR is still updated for every bit transmitted or received. Must
be used if SMBus mode is disabled.
1: Causes the transfer to use PEC. PEC byte generation (if master transmitter) or PEC byte verification (if master receiver) will
be performed.
• NBYTES: Number of Data Bytes in Transfer
The number of data bytes in the transfer. After the specified number of bytes have been transferred, a STOP condition is
transmitted if CMDR.STOP is one. In SMBus mode, if PEC is used, NBYTES includes the PEC byte, i.e. there are NBYTES-1
data bytes and a PEC byte.
• VALID: CMDR Valid
0: Indicates that CMDR does not contain a valid command.
1: Indicates that CMDR contains a valid command. This bit is cleared when the command is finished.
• STOP: Send STOP Condition
0: Do not transmit a STOP condition after the data bytes have been transmitted.
1: Transmit a STOP condition after the data bytes have been transmitted.
• START: Send START Condition
0: The transfer in CMDR should not commence with a START or REPEATED START condition.
1: The transfer in CMDR should commence with a START or REPEATED START condition. If the bus is free when the command
is executed, a START condition is used. If the bus is busy, a REPEATED START is used.
• REPSAME: Transfer is to Same Address as Previous Address
Only used in 10-bit addressing mode, always write to 0 in 7-bit addressing mode.
31 30 29 28 27 26 25 24
- - - - ACKLAST PECEN
23 22 21 20 19 18 17 16
NBYTES
15 14 13 12 11 10 9 8
VALID STOP START REPSAME TENBIT SADR[9:7]
76543210
SADR[6:0] READ
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Write this bit to one if the command in CMDR performs a repeated start to the same slave address as addressed in the previous
transfer in order to enter master receiver mode.
Write this bit to zero otherwise.
• TENBIT: Ten Bit Addressing Mode
0: Use 7-bit addressing mode.
1: Use 10-bit addressing mode. Must not be used when the TWIM is in SMBus mode.
• SADR: Slave Address
Address of the slave involved in the transfer. Bits 9-7 are don’t care if 7-bit addressing is used.
• READ: Transfer Direction
0: Allow the master to transmit data.
1: Allow the master to receive data.
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22.9.5 Next Command Register
Name: NCMDR
Access Type: Read/Write
Offset: 0x10
Reset Value: 0x00000000
This register is identical to CMDR. When the VALID bit in CMDR becomes 0, the content of NCMDR is copied into CMDR,
clearing the VALID bit in NCMDR. If the VALID bit in CMDR is cleared when NCMDR is written, the content is copied
immediately.
31 30 29 28 27 26 25 24
- - - - ACKLAST PECEN
23 22 21 20 19 18 17 16
NBYTES
15 14 13 12 11 10 9 8
VALID STOP START REPSAME TENBIT SADR[9:7]
76543210
SADR[6:0] READ
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22.9.6 Receive Holding Register
Name: RHR
Access Type: Read-only
Offset: 0x14
Reset Value: 0x00000000
• RXDATA: Received Data
When the RXRDY bit in the Status Register (SR) is one, this field contains a byte received from the TWI bus.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RXDATA
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22.9.7 Transmit Holding Register
Name: THR
Access Type: Write-only
Offset: 0x18
Reset Value: 0x00000000
• TXDATA: Data to Transmit
Write data to be transferred on the TWI bus here.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
TXDATA
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22.9.8 Status Register
Name: SR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000002
• MENB: Master Interface Enable
0: Master interface is disabled.
1: Master interface is enabled.
• STOP: Stop Request Accepted
This bit is one when a STOP request caused by writing a one to CR.STOP has been accepted, and transfer has stopped.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• PECERR: PEC Error
This bit is one when a SMBus PEC error occurred.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• TOUT: Timeout
This bit is one when a SMBus timeout occurred.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• SMBALERT: SMBus Alert
This bit is one when an SMBus Alert was received.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• ARBLST: Arbitration Lost
This bit is one when the actual state of the SDA line did not correspond to the data driven onto it, indicating a higher-priority
transmission in progress by a different master.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• DNAK: NAK in Data Phase Received
This bit is one when no ACK was received form slave during data transmission.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• ANAK: NAK in Address Phase Received
This bit is one when no ACK was received from slave during address phase
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• BUSFREE: Two-wire Bus is Free
This bit is one when activity has completed on the two-wire bus.
Otherwise, this bit is cleared.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - MENB
15 14 13 12 11 10 9 8
- STOP PECERR TOUT SMBALERT ARBLST DNAK ANAK
76543210
- - BUSFREE IDLE CCOMP CRDY TXRDY RXRDY
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• IDLE: Master Interface is Idle
This bit is one when no command is in progress, and no command waiting to be issued.
Otherwise, this bit is cleared.
• CCOMP: Command Complete
This bit is one when the current command has completed successfully.
This bit is zero if the command failed due to conditions such as a NAK receved from slave.
This bit is cleared by writing 1 to the corresponding bit in the Status Clear Register (SCR).
• CRDY: Ready for More Commands
This bit is one when CMDR and/or NCMDR is ready to receive one or more commands.
This bit is cleared when this is no longer true.
• TXRDY: THR Data Ready
This bit is one when THR is ready for one or more data bytes.
This bit is cleared when this is no longer true (i.e. THR is full or transmission has stopped).
• RXRDY: RHR Data Ready
This bit is one when RX data are ready to be read from RHR.
This bit is cleared when this is no longer true.
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22.9.9 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- STOP PECERR TOUT SMBALERT ARBLST DNAK ANAK
76543210
- - BUSFREE IDLE CCOMP CRDY TXRDY RXRDY
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22.9.10 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x24
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- STOP PECERR TOUT SMBALERT ARBLST DNAK ANAK
76543210
- - BUSFREE IDLE CCOMP CRDY TXRDY RXRDY
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22.9.11 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x28
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- STOP PECERR TOUT SMBALERT ARBLST DNAK ANAK
76543210
- - BUSFREE IDLE CCOMP CRDY TXRDY RXRDY
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22.9.12 Status Clear Register
Name: SCR
Access Type : Write-only
Offset: 0x2C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- STOP PECERR TOUT SMBALERT ARBLST DNAK ANAK
76543210
- - - - CCOMP - - -
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22.9.13 Parameter Register (PR)
Name: PR
Access Type: Read-only
Offset: 0x30
Reset Value: -
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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22.9.14 Version Register (VR)
Name: VR
Access Type: Read-only
Offset: 0x34
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION [11:8]
76543210
VERSION [7:0]
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22.10 Module Configuration
The specific configuration for each TWIM instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 22-7. Module Clock Name
Module Name Clock Name Description
TWIM0 CLK_TWIM0 Clock for the TWIM0 bus interface
TWIM1 CLK_TWIM1 Clock for the TWIM1 bus interface
Table 22-8. Register Reset Values
Register Reset Value
VERSION 0x00000110
PARAMETER 0x00000000
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23. Two-wire Slave Interface (TWIS)
Rev.: 1.2.0.1
23.1 Features
• Compatible with I²C standard
– Transfer speeds of 100 and 400 kbit/s
– 7 and 10-bit and General Call addressing
• Compatible with SMBus standard
– Hardware Packet Error Checking (CRC) generation and verification with ACK response
– SMBALERT interface
– 25 ms clock low timeout delay
– 25 ms slave cumulative clock low extend time
• Compatible with PMBus
• DMA interface for reducing CPU load
• Arbitrary transfer lengths, including 0 data bytes
• Optional clock stretching if transmit or receive buffers not ready for data transfer
• 32-bit Peripheral Bus interface for configuration of the interface
23.2 Overview
The Atmel Two-wire Slave Interface (TWIS) interconnects components on a unique two-wire
bus, made up of one clock line and one data line with speeds of up to 400 kbit/s, based on a
byte-oriented transfer format. It can be used with any Atmel Two-wire Interface bus, I²C, or
SMBus-compatible master. The TWIS is always a bus slave and can transfer sequential or single
bytes.
Below, Table 23-1 lists the compatibility level of the Atmel Two-wire Slave Interface and a full I²C
compatible device.
Note: 1. START + b000000001 + Ack + Sr
Table 23-1. Atmel TWIS Compatibility with I²C Standard
I²C Standard Atmel TWIS
Standard-mode (100 kbit/s) Supported
Fast-mode (400 kbit/s) Supported
7 or 10 bits Slave Addressing Supported
START BYTE(1) Not Supported
Repeated Start (Sr) Condition Supported
ACK and NAK Management Supported
Slope control and input filtering (Fast mode) Supported
Clock stretching Supported
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Below, Table 23-2 lists the compatibility level of the Atmel Two-wire Slave Interface and a full
SMBus compatible device.
23.3 List of Abbreviations
23.4 Block Diagram
Figure 23-1. Block Diagram
Table 23-2. Atmel TWIS Compatibility with SMBus Standard
SMBus Standard Atmel TWIS
Bus Timeouts Supported
Address Resolution Protocol Supported
Alert Supported
Packet Error Checking Supported
Table 23-3. Abbreviations
Abbreviation Description
TWI Two-wire Interface
A Acknowledge
NA Non Acknowledge
P Stop
S Start
Sr Repeated Start
SADR Slave Address
ADR Any address except SADR
R Read
W Write
Peripheral
Bus Bridge
Two-wire
Interface
I/O Controller
TWCK
TWD
Interrupt
Controller
TWI Interrupt
Power
Manager
CLK_TWIS
TWALM
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23.5 Application Block Diagram
Figure 23-2. Application Block Diagram
23.6 I/O Lines Description
23.7 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
23.7.1 I/O Lines
TWDand TWCK are bidirectional lines, connected to a positive supply voltage via a current
source or pull-up resistor (see Figure 23-5 on page 565). When the bus is free, both lines are
high. The output stages of devices connected to the bus must have an open-drain or open-collector
to perform the wired-AND function.
TWALM is used to implement the optional SMBus SMBALERT signal.
TWALM, TWD, and TWCK pins may be multiplexed with I/O Controller lines. To enable the
TWIS, the user must perform the following steps:
• Program the I/O Controller to:
– Dedicate TWD, TWCK, and optionally TWALM as peripheral lines.
– Define TWD, TWCK, and optionally TWALM as open-drain.
Host with
TWI
Interface
TWD
TWCK
Atmel TWI
serial EEPROM I²C RTC I²C LCD
controller
Slave 1 Slave 2 Slave 3
VDD
I²C temp.
sensor
Slave 4
Rp: Pull up value as given by the I²C Standard
Rp Rp
Table 23-4. I/O Lines Description
Pin Name Pin Description Type
TWD Two-wire Serial Data Input/Output
TWCK Two-wire Serial Clock Input/Output
TWALM SMBus SMBALERT Input/Output
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23.7.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the TWIS, the TWIS will stop functioning
and resume operation after the system wakes up from sleep mode. The TWIS is able to
wake the system from sleep mode upon address match, see Section 23.8.8 on page 572.
23.7.3 Clocks
The clock for the TWIS bus interface (CLK_TWIS) is generated by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable
the TWIS before disabling the clock, to avoid freezing the TWIS in an undefined state.
23.7.4 DMA
The TWIS DMA handshake interface is connected to the Peripheral DMA Controller. Using the
TWIS DMA functionality requires the Peripheral DMA Controller to be programmed after setting
up the TWIS.
23.7.5 Interrupts
The TWIS interrupt request lines are connected to the interrupt controller. Using the TWIS interrupts
requires the interrupt controller to be programmed first.
23.7.6 Debug Operation
When an external debugger forces the CPU into debug mode, the TWIS continues normal operation.
If the TWIS is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
23.8 Functional Description
23.8.1 Transfer Format
The data put on the TWD line must be 8 bits long. Data is transferred MSB first; each byte must
be followed by an acknowledgement. The number of bytes per transfer is unlimited (see Figure
23-4 on page 565).
Each transfer begins with a START condition and terminates with a STOP condition (see Figure
23-3).
• A high-to-low transition on the TWD line while TWCK is high defines the START condition.
• A low-to-high transition on the TWD line while TWCK is high defines a STOP condition.
Figure 23-3. START and STOP Conditions
TWD
TWCK
Start Stop
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Figure 23-4. Transfer Format
23.8.2 Operation
The TWIS has two modes of operation:
• Slave transmitter mode
• Slave receiver mode
A master is a device which starts and stops a transfer and generates the TWCK clock. A slave is
assigned an address and responds to requests from the master. These modes are described in
the following chapters.
Figure 23-5. Typical Application Block Diagram
23.8.2.1 Bus Timing
The Timing Register (TR) is used to control the timing of bus signals driven by the TWIS. TR
describes bus timings as a function of cycles of the prescaled CLK_TWIS. The clock prescaling
can be selected through TR.EXP.
TR has the following fields:
TLOWS: Prescaled clock cycles used to time SMBUS timeout TLOW:SEXT.
TWD
TWCK
Start Address R/W Ack Data Ack Data Ack Stop
Host with
TWI
Interface
TWD
TWCK
Atmel TWI
Serial EEPROM I²C RTC I²C LCD
Controller
Slave 1 Slave 2 Slave 3
VDD
I²C Temp.
Sensor
Slave 4
Rp: Pull up value as given by the I²C Standard
Rp Rp
fPRESCALED
f
CLK_TWIS
2 EXP 1 + = ------------------------
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TTOUT: Prescaled clock cycles used to time SMBUS timeout TTIMEOUT.
SUDAT: Non-prescaled clock cycles for data setup and hold count. Used to time TSU_DAT.
EXP: Specifies the clock prescaler setting used for the SMBUS timeouts.
Figure 23-6. Bus Timing Diagram
23.8.2.2 Setting Up and Performing a Transfer
Operation of the TWIS is mainly controlled by the Control Register (CR). The following list presents
the main steps in a typical communication:
3. Before any transfers can be performed, bus timings must be configured by writing to the
Timing Register (TR).If the Peripheral DMA Controller is to be used for the transfers, it
must be set up.
4. The Control Register (CR) must be configured with information such as the slave
address, SMBus mode, Packet Error Checking (PEC), number of bytes to transfer, and
which addresses to match.
The interrupt system can be set up to generate interrupt request on specific events or error conditions,
for example when a byte has been received.
The NBYTES register is only used in SMBus mode, when PEC is enabled. In I²C mode or in
SMBus mode when PEC is disabled, the NBYTES register is not used, and should be written to
zero. NBYTES is updated by hardware, so in order to avoid hazards, software updates of
NBYTES can only be done through writes to the NBYTES register.
23.8.2.3 Address Matching
The TWIS can be set up to match several different addresses. More than one address match
may be enabled simultaneously, allowing the TWIS to be assigned to several addresses. The
address matching phase is initiated after a START or REPEATED START condition. When the
TWIS receives an address that generates an address match, an ACK is automatically returned
to the master.
S t
HD:STA
t LOW
t
SU:DAT
t HIGH
t
HD:DAT
t LOW
P
t
SU:STO
Sr
t
SU:STA
t
SU:DAT
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In I²C mode:
• The address in CR.ADR is checked for address match if CR.SMATCH is one.
• The General Call address is checked for address match if CR.GCMATCH is one.
In SMBus mode:
• The address in CR.ADR is checked for address match if CR.SMATCH is one.
• The Alert Response Address is checked for address match if CR.SMAL is one.
• The Default Address is checked for address match if CR.SMDA is one.
• The Host Header Address is checked for address match if CR.SMHH is one.
23.8.2.4 Clock Stretching
Any slave or bus master taking part in a transfer may extend the TWCK low period at any time.
The TWIS may extend the TWCK low period after each byte transfer if CR.STREN is one and:
• Module is in slave transmitter mode, data should be transmitted, but THR is empty, or
• Module is in slave receiver mode, a byte has been received and placed into the internal
shifter, but the Receive Holding Register (RHR) is full, or
• Stretch-on-address-match bit CR.SOAM=1 and slave was addressed. Bus clock remains
stretched until all address match bits in the Status Register (SR) have been cleared.
If CR.STREN is zero and:
• Module is in slave transmitter mode, data should be transmitted but THR is empty: Transmit
the value present in THR (the last transmitted byte or reset value), and set SR.URUN.
• Module is in slave receiver mode, a byte has been received and placed into the internal
shifter, but RHR is full: Discard the received byte and set SR.ORUN.
23.8.2.5 Bus Errors
If a bus error (misplaced START or STOP) condition is detected, the SR.BUSERR bit is set and
the TWIS waits for a new START condition.
23.8.3 Slave Transmitter Mode
If the TWIS matches an address in which the R/W bit in the TWI address phase transfer is set, it
will enter slave transmitter mode and set the SR.TRA bit (note that SR.TRA is set one
CLK_TWIS cycle after the relevant address match bit in the same register is set).
After the address phase, the following actions are performed:
1. If SMBus mode and PEC is used, NBYTES must be set up with the number of bytes to
transmit. This is necessary in order to know when to transmit the PEC byte. NBYTES
can also be used to count the number of bytes received if using DMA.
2. Byte to transmit depends on I²C/SMBus mode and CR.PEC:
– If in I²C mode or CR.PEC is zero or NBYTES is non-zero: The TWIS waits until THR
contains a valid data byte, possibly stretching the low period of TWCK. After THR
contains a valid data byte, the data byte is transferred to a shifter, and then
SR.TXRDY is changed to one because the THR is empty again.
– SMBus mode and CR.PEC is one: If NBYTES is zero, the generated PEC byte is
automatically transmitted instead of a data byte from THR. TWCK will not be
stretched by the TWIS.
3. The data byte in the shifter is transmitted.
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4. NBYTES is updated. If CR.CUP is one, NBYTES is incremented, otherwise NBYTES is
decremented.
5. After each data byte has been transmitted, the master transmits an ACK (Acknowledge)
or NAK (Not Acknowledge) bit. If a NAK bit is received by the TWIS, the SR.NAK bit is
set. Note that this is done two CLK_TWIS cycles after TWCK has been sampled by the
TWIS to be HIGH (see Figure 23-9). The NAK indicates that the transfer is finished, and
the TWIS will wait for a STOP or REPEATED START. If an ACK bit is received, the
SR.NAK bit remains LOW. The ACK indicates that more data should be transmitted,
jump to step 2. At the end of the ACK/NAK clock cycle, the Byte Transfer Finished
(SR.BTF) bit is set. Note that this is done two CLK_TWIS cycles after TWCK has been
sampled by the TWIS to be LOW (see Figure 23-9). Also note that in the event that
SR.NAK bit is set, it must not be cleared before the SR.BTF bit is set to ensure correct
TWIS behavior.
6. If STOP is received, SR.TCOMP and SR.STO will be set.
7. If REPEATED START is received, SR.REP will be set.
The TWI transfers require the receiver to acknowledge each received data byte. During the
acknowledge clock pulse (9th pulse), the slave releases the data line (HIGH), enabling the master
to pull it down in order to generate the acknowledge. The slave polls the data line during this
clock pulse and sets the NAK bit in SR if the master does not acknowledge the data byte. A NAK
means that the master does not wish to receive additional data bytes. As with the other status
bits, an interrupt can be generated if enabled in the Interrupt Enable Register (IER).
SR.TXRDY is used as Transmit Ready for the Peripheral DMA Controller transmit channel.
The end of the complete transfer is marked by the SR.TCOMP bit changing from zero to one.
See Figure 23-7 and Figure 23-8.
Figure 23-7. Slave Transmitter with One Data Byte
TCOMP
TXRDY
Write THR (DATA) STOP sent by master
TWD S DADR R P A DATA N
NBYTES set to 1
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Figure 23-8. Slave Transmitter with Multiple Data Bytes
Figure 23-9. Timing Relationship between TWCK, SR.NAK, and SR.BTF
23.8.4 Slave Receiver Mode
If the TWIS matches an address in which the R/W bit in the TWI address phase transfer is
cleared, it will enter slave receiver mode and clear SR.TRA (note that SR.TRA is cleared one
CLK_TWIS cycle after the relevant address match bit in the same register is set).
After the address phase, the following is repeated:
1. If SMBus mode and PEC is used, NBYTES must be set up with the number of bytes to
receive. This is necessary in order to know which of the received bytes is the PEC byte.
NBYTES can also be used to count the number of bytes received if using DMA.
2. Receive a byte. Set SR.BTF when done.
3. Update NBYTES. If CR.CUP is written to one, NBYTES is incremented, otherwise
NBYTES is decremented. NBYTES is usually configured to count downwards if PEC is
used.
4. After a data byte has been received, the slave transmits an ACK or NAK bit. For ordinary
data bytes, the CR.ACK field controls if an ACK or NAK should be returned. If PEC
is enabled and the last byte received was a PEC byte (indicated by NBYTES equal to
zero), The TWIS will automatically return an ACK if the PEC value was correct, otherwise
a NAK will be returned.
5. If STOP is received, SR.TCOMP will be set.
6. If REPEATED START is received, SR.REP will be set.
The TWI transfers require the receiver to acknowledge each received data byte. During the
acknowledge clock pulse (9th pulse), the master releases the data line (HIGH), enabling the
S DADR R DATA n+5 A P A DATA n A DATA n+m N
TCOMP
TXRDY
Write THR (Data n)
NBYTES set to m
STOP sent by master
TWD
Write THR (Data n+1) Write THR (Data n+m)
Last data sent
DATA (LSB) N P
TWCK
SR.NAK
SR.BTF
t1 t1
t1: (CLK_TWIS period) x 2
TWD
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slave to pull it down in order to generate the acknowledge. The master polls the data line during
this clock pulse.
The SR.RXRDY bit indicates that a data byte is available in the RHR. The RXRDY bit is also
used as Receive Ready for the Peripheral DMA Controller receive channel.
Figure 23-10. Slave Receiver with One Data Byte
Figure 23-11. Slave Receiver with Multiple Data Bytes
23.8.5 Interactive ACKing Received Data Bytes
When implementing a register interface over TWI, it may sometimes be necessary or just useful
to report reads and writes to invalid register addresses by sending a NAK to the host. To be able
to do this, one must first receive the register address from the TWI bus, and then tell the TWIS
whether to ACK or NAK it. In normal operation of the TWIS, this is not possible because the controller
will automatically ACK the byte at about the same time as the RXRDY bit changes from
zero to one. Writing a one to the Stretch on Data Byte Received bit (CR.SODR) will stretch the
clock allowing the user to update CR.ACK bit before returning the desired value. After the last bit
in the data byte is received, the TWI bus clock is stretched, the received data byte is transferred
to the RHR register, and SR.BTF is set. At this time, the user can examine the received byte and
write the desired ACK or NACK value to CR.ACK. When the user clears SR.BTF, the desired
ACK value is transferred on the TWI bus. This makes it possible to look at the byte received,
determine if it is valid, and then decide to ACK or NAK it.
23.8.6 Using the Peripheral DMA Controller
The use of the Peripheral DMA Controller significantly reduces the CPU load. The user can set
up ring buffers for the Peripheral DMA Controller, containing data to transmit or free buffer space
to place received data. By initializing NBYTES to zero before a transfer, and writing a one to
CR.CUP, NBYTES is incremented by one each time a data has been transmitted or received.
This allows the user to detect how much data was actually transferred by the DMA system.
S DADR W DATA A P A
TCOMP
RXRDY
Read RHR
TWD
TWD S DADR W DATA n A A A DATA (n+1) A DATA (n+m) DATA (n+m)-1 P A
TCOMP
RXRDY
Read RHR
DATA n
Read RHR
DATA (n+1)
Read RHR
DATA (n+m)-1
Read RHR
DATA (n+m)
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To assure correct behavior, respect the following programming sequences:
23.8.6.1 Data Transmit with the Peripheral DMA Controller
1. Initialize the transmit Peripheral DMA Controller (memory pointers, size, etc.).
2. Configure the TWIS (ADR, NBYTES, etc.).
3. Start the transfer by enabling the Peripheral DMA Controller to transmit.
4. Wait for the Peripheral DMA Controller end-of-transmit flag.
5. Disable the Peripheral DMA Controller.
23.8.6.2 Data Receive with the Peripheral DMA Controller
1. Initialize the receive Peripheral DMA Controller (memory pointers, size - 1, etc.).
2. Configure the TWIS (ADR, NBYTES, etc.).
3. Start the transfer by enabling the Peripheral DMA Controller to receive.
4. Wait for the Peripheral DMA Controller end-of-receive flag.
5. Disable the Peripheral DMA Controller.
23.8.7 SMBus Mode
SMBus mode is enabled by writing a one to the SMBus Mode Enable (SMEN) bit in CR. SMBus
mode operation is similar to I²C operation with the following exceptions:
• Only 7-bit addressing can be used.
• The SMBus standard describes a set of timeout values to ensure progress and throughput on
the bus. These timeout values must be written to TR.
• Transmissions can optionally include a CRC byte, called Packet Error Check (PEC).
• A dedicated bus line, SMBALERT, allows a slave to get a master’s attention.
• A set of addresses have been reserved for protocol handling, such as Alert Response
Address (ARA) and Host Header (HH) Address. Address matching on these addresses can
be enabled by configuring CR appropriately.
23.8.7.1 Packet Error Checking (PEC)
Each SMBus transfer can optionally end with a CRC byte, called the PEC byte. Writing a one to
the Packet Error Checking Enable (PECEN) bit in CR enables automatic PEC handling in the
current transfer. The PEC generator is always updated on every bit transmitted or received, so
that PEC handling on following linked transfers will be correct.
In slave receiver mode, the master calculates a PEC value and transmits it to the slave after all
data bytes have been transmitted. Upon reception of this PEC byte, the slave will compare it to
the PEC value it has computed itself. If the values match, the data was received correctly, and
the slave will return an ACK to the master. If the PEC values differ, data was corrupted, and the
slave will return a NAK value. The SR.SMBPECERR bit is set automatically if a PEC error
occurred.
In slave transmitter mode, the slave calculates a PEC value and transmits it to the master after
all data bytes have been transmitted. Upon reception of this PEC byte, the master will compare
it to the PEC value it has computed itself. If the values match, the data was received correctly. If
the PEC values differ, data was corrupted, and the master must take appropriate action.
The PEC byte is automatically inserted in a slave transmitter transmission if PEC enabled when
NBYTES reaches zero. The PEC byte is identified in a slave receiver transmission if PEC
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enabled when NBYTES reaches zero. NBYTES must therefore be set to the total number of
data bytes in the transmission, including the PEC byte.
23.8.7.2 Timeouts
The Timing Register (TR) configures the SMBus timeout values. If a timeout occurs, the slave
will leave the bus. The SR.SMBTOUT bit is also set.
23.8.7.3 SMBALERT
A slave can get the master’s attention by pulling the SMBALERT line low. This is done by writing
a one to the SMBus Alert (SMBALERT) bit in CR. This will also enable address match on the
Alert Response Address (ARA).
23.8.8 Wakeup from Sleep Modes by TWI Address Match
The TWIS is able to wake the device up from a sleep mode upon an address match, including
sleep modes where CLK_TWIS is stopped. After detecting the START condition on the bus, The
TWIS will stretch TWCK until CLK_TWIS has started. The time required for starting CLK_TWIS
depends on which sleep mode the device is in. After CLK_TWIS has started, the TWIS releases
its TWCK stretching and receives one byte of data on the bus. At this time, only a limited part of
the device, including the TWIS, receives a clock, thus saving power. The TWIS goes on to
receive the slave address. If the address phase causes a TWIS address match, the entire
device is wakened and normal TWIS address matching actions are performed. Normal TWI
transfer then follows. If the TWIS is not addressed, CLK_TWIS is automatically stopped and the
device returns to its original sleep mode.
23.8.9 Identifying Bus Events
This chapter lists the different bus events, and how these affects the bits in the TWIS registers.
This is intended to help writing drivers for the TWIS.
Table 23-5. Bus Events
Event Effect
Slave transmitter has sent a
data byte
SR.THR is cleared.
SR.BTF is set.
The value of the ACK bit sent immediately after the data byte is given
by CR.ACK.
Slave receiver has received
a data byte
SR.RHR is set.
SR.BTF is set.
SR.NAK updated according to value of ACK bit received from master.
Start+Sadr on bus, but
address is to another slave None.
Start+Sadr on bus, current
slave is addressed, but
address match enable bit in
CR is not set
None.
Start+Sadr on bus, current
slave is addressed,
corresponding address
match enable bit in CR set
Correct address match bit in SR is set.
SR.TRA updated according to transfer direction (updating is done one
CLK_TWIS cycle after address match bit is set)
Slave enters appropriate transfer direction mode and data transfer
can commence.
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Start+Sadr on bus, current
slave is addressed,
corresponding address
match enable bit in CR set,
SR.STREN and SR.SOAM
are set.
Correct address match bit in SR is set.
SR.TRA updated according to transfer direction (updating is done one
CLK_TWIS cycle after address match bit is set).
Slave stretches TWCK immediately after transmitting the address
ACK bit. TWCK remains stretched until all address match bits in SR
have been cleared.
Slave enters appropriate transfer direction mode and data transfer
can commence.
Repeated Start received
after being addressed
SR.REP set.
SR.TCOMP unchanged.
Stop received after being
addressed
SR.STO set.
SR.TCOMP set.
Start, Repeated Start, or
Stop received in illegal
position on bus
SR.BUSERR set.
SR.STO and SR.TCOMP may or may not be set depending on the
exact position of an illegal stop.
Data is to be received in
slave receiver mode,
SR.STREN is set, and RHR
is full
TWCK is stretched until RHR has been read.
Data is to be transmitted in
slave receiver mode,
SR.STREN is set, and THR
is empty
TWCK is stretched until THR has been written.
Data is to be received in
slave receiver mode,
SR.STREN is cleared, and
RHR is full
TWCK is not stretched, read data is discarded.
SR.ORUN is set.
Data is to be transmitted in
slave receiver mode,
SR.STREN is cleared, and
THR is empty
TWCK is not stretched, previous contents of THR is written to bus.
SR.URUN is set.
SMBus timeout received SR.SMBTOUT is set.
TWCK and TWD are immediately released.
Slave transmitter in SMBus
PEC mode has transmitted
a PEC byte, that was not
identical to the PEC
calculated by the master
receiver.
Master receiver will transmit a NAK as usual after the last byte of a
master receiver transfer.
Master receiver will retry the transfer at a later time.
Slave receiver discovers
SMBus PEC Error
SR.SMBPECERR is set.
NAK returned after the data byte.
Table 23-5. Bus Events
Event Effect
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23.9 User Interface
Note: 1. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 23-6. TWIS Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Read/Write 0x00000000
0x04 NBYTES Register NBYTES Read/Write 0x00000000
0x08 Timing Register TR Read/Write 0x00000000
0x0C Receive Holding Register RHR Read-only 0x00000000
0x10 Transmit Holding Register THR Write-only 0x00000000
0x14 Packet Error Check Register PECR Read-only 0x00000000
0x18 Status Register SR Read-only 0x00000002
0x1C Interrupt Enable Register IER Write-only 0x00000000
0x20 Interrupt Disable Register IDR Write-only 0x00000000
0x24 Interrupt Mask Register IMR Read-only 0x00000000
0x28 Status Clear Register SCR Write-only 0x00000000
0x2C Parameter Register PR Read-only -(1)
0x30 Version Register VR Read-only -(1)
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23.9.1 Control Register
Name: CR
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• TENBIT: Ten Bit Address Match
0: Disables Ten Bit Address Match.
1: Enables Ten Bit Address Match.
• ADR: Slave Address
Slave address used in slave address match. Bits 9:0 are used if in 10-bit mode, bits 6:0 otherwise.
• SODR: Stretch Clock on Data Byte Reception
0: Does not stretch bus clock immediately before ACKing a received data byte.
1: Stretches bus clock immediately before ACKing a received data byte.
• SOAM: Stretch Clock on Address Match
0: Does not stretch bus clock after address match.
1: Stretches bus clock after address match.
• CUP: NBYTES Count Up
0: Causes NBYTES to count down (decrement) per byte transferred.
1: Causes NBYTES to count up (increment) per byte transferred.
• ACK: Slave Receiver Data Phase ACK Value
0: Causes a low value to be returned in the ACK cycle of the data phase in slave receiver mode.
1: Causes a high value to be returned in the ACK cycle of the data phase in slave receiver mode.
• PECEN: Packet Error Checking Enable
0: Disables SMBus PEC (CRC) generation and check.
1: Enables SMBus PEC (CRC) generation and check.
• SMHH: SMBus Host Header
0: Causes the TWIS not to acknowledge the SMBus Host Header.
1: Causes the TWIS to acknowledge the SMBus Host Header.
• SMDA: SMBus Default Address
0: Causes the TWIS not to acknowledge the SMBus Default Address.
1: Causes the TWIS to acknowledge the SMBus Default Address.
• SMBALERT: SMBus Alert
0: Causes the TWIS to release the SMBALERT line and not to acknowledge the SMBus Alert Response Address (ARA).
1: Causes the TWIS to pull down the SMBALERT line and to acknowledge the SMBus Alert Response Address (ARA).
31 30 29 28 27 26 25 24
- - - - - TENBIT ADR[9:8]
23 22 21 20 19 18 17 16
ADR[7:0]
15 14 13 12 11 10 9 8
SODR SOAM CUP ACK PECEN SMHH SMDA SMBALERT
76543210
SWRST - - STREN GCMATCH SMATCH SMEN SEN
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• SWRST: Software Reset
This bit will always read as 0.
Writing a zero to this bit has no effect.
Writing a one to this bit resets the TWIS.
• STREN: Clock Stretch Enable
0: Disables clock stretching if RHR/THR buffer full/empty. May cause over/underrun.
1: Enables clock stretching if RHR/THR buffer full/empty.
• GCMATCH: General Call Address Match
0: Causes the TWIS not to acknowledge the General Call Address.
1: Causes the TWIS to acknowledge the General Call Address.
• SMATCH: Slave Address Match
0: Causes the TWIS not to acknowledge the Slave Address.
1: Causes the TWIS to acknowledge the Slave Address.
• SMEN: SMBus Mode Enable
0: Disables SMBus mode.
1: Enables SMBus mode.
• SEN: Slave Enable
0: Disables the slave interface.
1: Enables the slave interface.
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23.9.2 NBYTES Register
Name: NBYTES
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• NBYTES: Number of Bytes to Transfer
Writing to this field updates the NBYTES counter. The field can also be read to learn the progress of the transfer. NBYTES can
be incremented or decremented automatically by hardware.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
NBYTES
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23.9.3 Timing Register
Name: TR
Access Type: Read/Write
Offset: 0x08
Reset Value: 0x00000000
• EXP: Clock Prescaler
Used to specify how to prescale the SMBus TLOWS counter. The counter is prescaled according to the following formula:
• SUDAT: Data Setup Cycles
Non-prescaled clock cycles for data setup count. Used to time TSU_DAT. Data is driven SUDAT cycles after TWCK low detected.
This timing is used for timing the ACK/NAK bits, and any data bits driven in slave transmitter mode.
• TTOUT: SMBus TTIMEOUT Cycles
Prescaled clock cycles used to time SMBus TTIMEOUT.
• TLOWS: SMBus TLOW:SEXT Cycles
Prescaled clock cycles used to time SMBus TLOW:SEXT.
31 30 29 28 27 26 25 24
EXP - - - -
23 22 21 20 19 18 17 16
SUDAT
15 14 13 12 11 10 9 8
TTOUT
76543210
TLOWS
f
PRESCALED
f
CLK_TWIS
2 EXP 1 + = ------------------------
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23.9.4 Receive Holding Register
Name: RHR
Access Type: Read-only
Offset: 0x0C
Reset Value: 0x00000000
• RXDATA: Received Data Byte
When the RXRDY bit in the Status Register (SR) is one, this field contains a byte received from the TWI bus.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RXDATA
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23.9.5 Transmit Holding Register
Name: THR
Access Type: Write-only
Offset: 0x10
Reset Value: 0x00000000
• TXDATA: Data Byte to Transmit
Write data to be transferred on the TWI bus here.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
TXDATA
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23.9.6 Packet Error Check Register
Name: PECR
Access Type: Read-only
Offset: 0x14
Reset Value: 0x00000000
• PEC: Calculated PEC Value
The calculated PEC value. Updated automatically by hardware after each byte has been transferred. Reset by hardware after a
STOP condition. Provided if the user manually wishes to control when the PEC byte is transmitted, or wishes to access the PEC
value for other reasons. In ordinary operation, the PEC handling is done automatically by hardware.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
PEC
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23.9.7 Status Register
Name: SR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x000000002
• BTF: Byte Transfer Finished
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when byte transfer has completed.
• REP: Repeated Start Received
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when a REPEATED START condition is received.
• STO: Stop Received
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the STOP condition is received.
• SMBDAM: SMBus Default Address Match
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the received address matched the SMBus Default Address.
• SMBHHM: SMBus Host Header Address Match
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the received address matched the SMBus Host Header Address.
• SMBALERTM: SMBus Alert Response Address Match
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the received address matched the SMBus Alert Response Address.
• GCM: General Call Match
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the received address matched the General Call Address.
• SAM: Slave Address Match
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when the received address matched the Slave Address.
• BUSERR: Bus Error
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when a misplaced START or STOP condition has occurred.
31 30 29 28 27 26 25 24
-- - -----
23 22 21 20 19 18 17 16
BTF REP STO SMBDAM SMBHHM SMBALERTM GCM SAM
15 14 13 12 11 10 9 8
- BUSERR SMBPECERR SMBTOUT - - - NAK
76 5 43210
ORUN URUN TRA - TCOMP SEN TXRDY RXRDY
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• SMBPECERR: SMBus PEC Error
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when a SMBus PEC error has occurred.
• SMBTOUT: SMBus Timeout
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when a SMBus timeout has occurred.
• NAK: NAK Received
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when a NAK was received from the master during slave transmitter operation.
• ORUN: Overrun
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when an overrun has occurred in slave receiver mode. Can only occur if CR.STREN is zero.
• URUN: Underrun
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when an underrun has occurred in slave transmitter mode. Can only occur if CR.STREN is zero.
• TRA: Transmitter Mode
0: The slave is in slave receiver mode.
1: The slave is in slave transmitter mode.
• TCOMP: Transmission Complete
This bit is cleared when the corresponding bit in SCR is written to one.
This bit is set when transmission is complete. Set after receiving a STOP after being addressed.
• SEN: Slave Enabled
0: The slave interface is disabled.
1: The slave interface is enabled.
• TXRDY: TX Buffer Ready
0: The TX buffer is full and should not be written to.
1: The TX buffer is empty, and can accept new data.
• RXRDY: RX Buffer Ready
0: No RX data ready in RHR.
1: RX data is ready to be read from RHR.
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23.9.8 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x1C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will write a one to the corresponding bit in IMR.
31 30 29 28 27 26 25 24
-- - -----
23 22 21 20 19 18 17 16
BTF REP STO SMBDAM SMBHHM SMBALERTM GCM SAM
15 14 13 12 11 10 9 8
- BUSERR SMBPECERR SMBTOUT - - - NAK
76 5 43210
ORUN URUN - - TCOMP - TXRDY RXRDY
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23.9.9 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
-- - -----
23 22 21 20 19 18 17 16
BTF REP STO SMBDAM SMBHHM SMBALERTM GCM SAM
15 14 13 12 11 10 9 8
- BUSERR SMBPECERR SMBTOUT - - - NAK
76 5 43210
ORUN URUN - - TCOMP - TXRDY RXRDY
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23.9.10 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x24
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
-- - -----
23 22 21 20 19 18 17 16
BTF REP STO SMBDAM SMBHHM SMBALERTM GCM SAM
15 14 13 12 11 10 9 8
- BUSERR SMBPECERR SMBTOUT - - - NAK
76 5 43210
ORUN URUN - - TCOMP - TXRDY RXRDY
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23.9.11 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x28
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
-- - -----
23 22 21 20 19 18 17 16
BTF REP STO SMBDAM SMBHHM SMBALERTM GCM SAM
15 14 13 12 11 10 9 8
- BUSERR SMBPECERR SMBTOUT - - - NAK
76 5 43210
ORUN URUN - - TCOMP - - -
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23.9.12 Parameter Register
Name: PR
Access Type: Read-only
Offset: 0x2C
Reset Value: -
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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23.9.13 Version Register (VR)
Name: VR
Access Type: Read-only
Offset: 0x30
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION [11:8]
76543210
VERSION [7:0]
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23.10 Module Configuration
The specific configuration for each TWIS instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 23-7. Module Clock Name
Module Name Clock Name Description
TWIS0 CLK_TWIS0 Clock for the TWIS0 bus interface
TWIS1 CLK_TWIS1 Clock for the TWIS1 bus interface
Table 23-8. Register Reset Values
Register Reset Value
VERSION 0x00000120
PARAMETER 0x00000000
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24. Inter-IC Sound Controller (IISC)
Rev: 1.0.0.0
24.1 Features
• Compliant with Inter-IC Sound (I2
S) bus specification
• Master, slave, and controller modes:
– Slave: data received/transmitted
– Master: data received/transmitted and clocks generated
– Controller: clocks generated
• Individual enable and disable of receiver, transmitter, and clocks
• Configurable clock generator common to receiver and transmitter:
– Suitable for a wide range of sample frequencies (fs), including 32kHz, 44.1kHz, 48kHz,
88.2kHz, 96kHz, and 192kHz
– 16fs to 1024fs Master Clock generated for external oversampling ADCs
• Several data formats supported:
– 32-, 24-, 20-, 18-, 16-, and 8-bit mono or stereo format
– 16- and 8-bit compact stereo format, with left and right samples packed in the same word to
reduce data transfers
• DMA interfaces for receiver and transmitter to reduce processor overhead:
– Either one DMA channel for both audio channels, or
– One DMA channel per audio channel
• Smart holding registers management to avoid audio channels mix after overrun or underrun
24.2 Overview
The Inter-IC Sound Controller (IISC) provides a 5-wire, bidirectional, synchronous, digital audio
link with external audio devices: ISDI, ISDO, IWS, ISCK, and IMCK pins.
This controller is compliant with the Inter-IC Sound (I2
S) bus specification.
The IISC consists of a Receiver, a Transmitter, and a common Clock Generator, that can be
enabled separately, to provide Master, Slave, or Controller modes with Receiver, Transmitter, or
both active.
Peripheral DMA channels, separate for the Receiver and for the Transmitter, allow a continuous
high bitrate data transfer without processor intervention to the following:
• Audio CODECs in Master, Slave, or Controller mode
• Stereo DAC or ADC through dedicated I2
S serial interface
The IISC can use either a single DMA channel for both audio channels or one DMA channel per
audio channel.
The 8- and 16-bit compact stereo format allows reducing the required DMA bandwidth by transferring
the left and right samples within the same data word.
In Master Mode, the IISC allows outputting a 16 fs to 1024fs Master Clock, in order to provide an
oversampling clock to an external audio codec or digital signal processor (DSP).
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24.3 Block Diagram
Figure 24-1. IISC Block Diagram
24.4 I/O Lines Description
24.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
24.5.1 I/O lines
The IISC pins may be multiplexed with I/O Controller lines. The user must first program the I/O
Controller to assign the desired IISC pins to their peripheral function. If the IISC I/O lines are not
used by the application, they can be used for other purposes by the I/O Controller. It is required
to enable only the IISC inputs and outputs actually in use.
24.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the IISC, the IISC will stop functioning
and resume operation after the system wakes up from sleep mode.I/O Controller
ISCK
IWS
ISDI
ISDO
IMCK
Receiver
Clocks
Transmitter
Peripheral Bus interface
Generic clock
PB Peripheral
Bus Bridge
Interrupt
Controller
SCIF
Power
Manager PB clock
IRQ
Peripheral
DMA
Controller
Rx
Tx
IISC
Table 24-1. I/O Lines Description
Pin Name Pin Description Type
IMCK Master Clock Output
ISCK Serial Clock Input/Output
IWS I2
S Word Select Input/Output
ISDI Serial Data Input Input
ISDO Serial Data Output Output
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24.5.3 Clocks
The clock for the IISC bus interface (CLK_IISC) is generated by the Power Manager. This clock
is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable the
IISC before disabling the clock, to avoid freezing the IISC in an undefined state.
One of the generic clocks is connected to the IISC. The generic clock (GCLK_IISC) can be set to
a wide range of frequencies and clock sources. The GCLK_IISC must be enabled and configured
before use. Refer to the module configuration section for details on the GCLK_IISC used
for the IISC. The frequency for this clock has to be set as described in Table.
24.5.4 DMA
The IISC DMA handshake interfaces are connected to the Peripheral DMA Controller. Using the
IISC DMA functionality requires the Peripheral DMA Controller to be programmed first.
24.5.5 Interrupts
The IISC interrupt line is connected to the Interrupt Controller. Using the IISC interrupt requires
the Interrupt Controller to be programmed first.
24.5.6 Debug Operation
When an external debugger forces the CPU into debug mode, the IISC continues normal operation.
If this module is configured in a way that requires it to be periodically serviced by the CPU
through interrupt requests or similar, improper operation or data loss may result during
debugging.
24.6 Functional Description
24.6.1 Initialization
The IISC features a Receiver, a Transmitter, and, for Master and Controller modes, a Clock
Generator. Receiver and Transmitter share the same Serial Clock and Word Select.
Before enabling the IISC, the chosen configuration must be written to the Mode Register (MR).
The IMCKMODE, MODE, and DATALENGTH fields in the MR register must be written. If the
IMCKMODE field is written as one, then the IMCKFS field should be written with the chosen
ratio, as described in Section 24.6.5 ”Serial Clock and Word Select Generation” on page 595.
Once the Mode Register has been written, the IISC Clock Generator, Receiver, and Transmitter
can be enabled by writing a one to the CKEN, RXEN, and TXEN bits in the Control Register
(CR). The Clock Generator can be enabled alone, in Controller Mode, to output clocks to the
IMCK, ISCK, and IWS pins. The Clock Generator must also be enabled if the Receiver or the
Transmitter is enabled.
The Clock Generator, Receiver, and Transmitter can be disabled independently by writing a one
to CR.CXDIS, CR.RXDIS and/or CR.TXDIS respectively. Once requested to stop, they will only
stop when the transmission of the pending frame transmission will be completed.
24.6.2 Basic Operation
The Receiver can be operated by reading the Receiver Holding Register (RHR), whenever the
Receive Ready (RXRDY) bit in the Status Register (SR) is set. Successive values read from
RHR will correspond to the samples from the left and right audio channels for the successive
frames.
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The Transmitter can be operated by writing to the Transmitter Holding Register (RHR), whenever
the Transmit Ready (TXRDY) bit in the Status Register (SR) is set. Successive values
written to THR should correspond to the samples from the left and right audio channels for the
successive frames.
The Receive Ready and Transmit Ready bits can be polled by reading the Status Register.
The IISC processor load can be reduced by enabling interrupt-driven operation. The RXRDY
and/or TXRDY interrupt requests can be enabled by writing a one to the corresponding bit in the
Interrupt Enable Register (IER). The interrupt service routine associated to the IISC interrupt
request will then be executed whenever the Receive Ready or the Transmit Ready status bit is
set.
24.6.3 Master, Controller, and Slave Modes
In Master and Controller modes, the IISC provides the Master Clock, the Serial Clock and the
Word Select. IMCK, ISCK, and IWS pins are outputs.
In Controller mode, the IISC Receiver and Transmitter are disabled. Only the clocks are enabled
and used by an external receiver and/or transmitter.
In Slave mode, the IISC receives the Serial Clock and the Word Select from an external master.
ISCK and IWS pins are inputs.
The mode is selected by writing the MODE field of the Mode Register (MR). Since the MODE
field changes the direction of the IWS and ISCK pins, the Mode Register should only be written
when the IISC is stopped, in order to avoid unwanted glitches on the IWS and ISCK pins.
24.6.4 I2
S Reception and Transmission Sequence
As specified in the I2
S protocol, data bits are left-adjusted in the Word Select time slot, with the
MSB transmitted first, starting one clock period after the transition on the Word Select line.
Figure 24-2. I
2
S Reception and Transmission Sequence
Data bits are sent on the falling edge of the Serial Clock and sampled on the rising edge of the
Serial Clock. The Word Select line indicates the channel in transmission, a low level for the left
channel and a high level for the right channel.
The length of transmitted words can be chosen among 8, 16, 18, 20, 24, and 32 bits by writing
the MR.DATALENGTH field.
If the time slot allows for more data bits than written in the MR.DATALENGTH field, zeroes are
appended to the transmitted data word or extra received bits are discarded. If the time slot
allows for less data bits than written, the extra bits to be transmitted are not sent or the missing
bits are set to zero in the received data word.
Serial Clock ISCK
Word Select IWS
Data ISDI/ISDO MSB
Left Channel
LSB MSB
Right Channel
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24.6.5 Serial Clock and Word Select Generation
The generation of clocks in the IISC is described in Figure 24-3 on page 596.
In Slave mode, the Serial Clock and Word Select Clock are driven by an external master. ISCK
and IWS pins are inputs and no generic clock is required by the IISC.
In Master mode, the user can configure the Master Clock, Serial Clock, and Word Select Clock
through the Mode Register (MR). IMCK, ISCK, and IWS pins are outputs and a generic clock is
used to derive the IISC clocks.
Audio codecs connected to the IISC pins may require a Master Clock signal with a frequency
multiple of the audio sample frequency (fs), such as 256fs. When the IISC is in Master mode,
writing a one to MR.IMCKMODE will output GCLK_IISC as Master Clock to the IMCK pin, and
will divide GCLK_IISC to create the internal bit clock, output on the ISCK pin. The clock division
factor is defined by writing to MR.IMCKFS and MR.DATALENGTH, as described ”IMCKFS:
Master Clock to fs Ratio” on page 602.
The Master Clock (IMCK) frequency is 16*(IMCKFS+1) times the sample frequency (fs), i.e. IWS
frequency. The Serial Clock (ISCK) frequency is 2*Slot Length times the sample frequency (fs),
where Slot Length is defined in Table 24-2 on page 595.
Warning: MR.IMCKMODE should only be written as one if the Master Clock frequency is strictly
higher than the Serial Clock.
If a Master Clock output is not required, the GCLK_IISC generic clock is used as ISCK, by writing
a zero to MR.IMCKMODE. Alternatively, if the frequency of the generic clock used is a
multiple of the required ISCK frequency, the IMCK to ISCK divider can be used with the ratio
defined by writing the MR.IMCKFS field.
The IWS pin is used as Word Select as described in Section 24.6.4.
Table 24-2. Slot Length
MR.DATALENGTH Word Length Slot Length
0 32 bits 32
1 24 bits
32 if MR.IWS24 is zero
24 if MR.IWS24 is one 2 20 bits
3 18 bits
4 16 bits
16
5 16 bits compact stereo
6 8 bits
8
7 8 bits compact stereo
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Figure 24-3. IISC Clocks Generation
24.6.6 Mono
When the Transmit Mono (TXMONO) in the Mode Register is set, data written to the left channel
is duplicated to the right output channel.
When the Receive Mono (RXMONO) in the Mode Register is set, data received from the left
channel is duplicated to the right channel.
24.6.7 Holding Registers
The IISC user interface includes a Receive Holding Register (RHR) and a Transmit Holding
Register (THR). RHR and THR are used to access audio samples for both audio channels.
When a new data word is available in the RHR register, the Receive Ready bit (RXRDY) in the
Status Register (SR) is set. Reading the RHR register will clear this bit.
A receive overrun condition occurs if a new data word becomes available before the previous
data word has been read from the RHR register. Then, the Receive Overrun bit in the Status
Register will be set and bit i of the RXORCH field in the Status Register is set, where i is the current
receive channel number.
When the THR register is empty, the Transmit Ready bit (TXRDY) in the Status Register (SR) is
set. Writing into the THR register will clear this bit.
A transmit underrun condition occurs if a new data word needs to be transmitted before it has
been written to the THR register. Then, the Transmit Underrun bit in the Status Register will be
set and bit i of the TXORCH field in the Status Register is set, where i is the current transmit
channel number. If the TXSAME bit in the Mode Register is zero, then a zero data word is transmitted
in case of underrun. If MR.TXSAME is one, then the previous data word for the current
transmit channel number is transmitted.
MR.MODE = SLAVE Clock
divider MR.DATALENGTH
GCLK_IISC Clock
enable
Clock
divider
CR.CKEN/CKDIS MR.IMCKMODE
MR.DATALENGTH
MR.IMCKFS
MR.IMCKMODE 0 1
IMCK pin output
Clock
enable
CR.CKEN/CKDIS
Internal
bit clock ISCK pin input 1
0
ISCK pin output
Internal
word clock IWS pin input 1
0
IWS pin output
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Data words are right-justified in the RHR and THR registers. For 16-bit compact stereo, the left
sample uses bits 15 through 0 and the right sample uses bits 31 through 16 of the same data
word. For 8-bit compact stereo, the left sample uses bits 7 through 0 and the right sample uses
bits 15 through 8 of the same data word.
24.6.8 DMA Operation
The Receiver and the Transmitter can each be connected either to one single Peripheral DMA
channel or to one Peripheral DMA channel per data channel. This is selected by writing to the
MR.RXDMA and MR.TXDMA bits. If a single Peripheral DMA channel is selected, all data samples
use IISC Receiver or Transmitter DMA channel 0.
The Peripheral DMA reads from the RHR register and writes to the RHR register for both audio
channels, successively.
The Peripheral DMA transfers may use 32-bit word, 16-bit halfword, or 8-bit byte according to
the value of the MR.DATALENGTH field.
24.6.9 Loop-back Mode
For debugging purposes, the IISC can be configured to loop back the Transmitter to the
Receiver. Writing a one to the MR.LOOP bit will internally connect ISDO to ISDI, so that the
transmitted data is also received. Writing a zero to MR.LOOP will restore the normal behavior
with independent Receiver and Transmitter. As for other changes to the Receiver or Transmitter
configuration, the IISC Receiver and Transmitter must be disabled before writing to the MR register
to update MR.LOOP.
24.6.10 Interrupts
An IISC interrupt request can be triggered whenever one or several of the following bits are set
in the Status Register (SR): Receive Ready (RXRDY), Receive Overrun (RXOR), Transmit
Ready (TXRDY), or Transmit Underrun (TXOR).
The interrupt request will be generated if the corresponding bit in the Interrupt Mask Register
(IMR) is set. Bits in IMR are set by writing a one to the corresponding bit in the Interrupt Enable
Register (IER), and cleared by writing a one to the corresponding bit in the Interrupt Disable
Register (IDR). The interrupt request remains active until the corresponding bit in SR is cleared
by writing a one the corresponding bit in the Status Clear Register (SCR).
For debugging purposes, interrupt requests can be simulated by writing a one to the corresponding
bit in the Status Set Register (SSR).
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Figure 24-4. Interrupt Block Diagram
24.7 IISC Application Examples
The IISC can support several serial communication modes used in audio or high-speed serial
links. Some standard applications are shown in the following figures. All serial link applications
supported by the IISC are not listed here.
Figure 24-5. Audio Application Block Diagram
IER IDR IMR
Set Clear
Interrupt
Control
IISC Interrupt
Request
TXRDY
TXUR
Transmitter
Receiver
RXRDY
RXOR
Serial Clock
Word Select
Serial Data Out MSB LSB MSB
Serial Data Out
Word Select
Serial Clock
IISC
ISCK
IWS
ISDO
ISDI
EXTERNAL
I
2
S
RECEIVER
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Figure 24-6. Codec Application Block Diagram
Figure 24-7. Time Slot Application Block Diagram
IISC Word Select
Serial Data Out
Serial Data In
EXTERNAL
AUDIO
CODEC
IMCK
IWS
ISDO
ISDI
Serial Clock
Master Clock
ISCK
Right Time Slot
Serial Clock
Word Select
Serial Data Out
Serial Data In
Dstart Dend
Left Time Slot
EXTERNAL
AUDIO
CODEC
for Left
Time Slot
EXTERNAL
AUDIO
CODEC
for Right
Time Slot
Serial Data In
Serial Data Out
Word Select
Serial Clock
Serial Clock
Word Select
Serial Data Out
Serial Data In
Dstart
Left Time Slot Right Time Slot
Dend
IISC
ISCK
IWS
ISDO
ISDI
Master Clock IMCK
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24.8 User Interface
Note: 1. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 24-3. IISC Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Write-only 0x00000000
0x04 Mode Register MR Read/Write 0x00000000
0x08 Status Register SR Read-only 0x00000000
0x0C Status Clear Register SCR Write-only 0x00000000
0x10 Status Set Register SSR Write-only 0x00000000
0x14 Interrupt Enable Register IER Write-only 0x00000000
0x18 Interrupt Disable Register IDR Write-only 0x00000000
0x1C Interrupt Mask Register IMR Read-only 0x00000000
0x20 Receiver Holding Register RHR Read-only 0x00000000
0x24 Transmitter Holding Register THR Write-only 0x00000000
0x28 Version Register VERSION Read-only -
(1)
0x2C Parameter Register PARAMETER Read-only -
(1)
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24.8.1 Control Register
Name: CR
Access Type: Write-only
Offset: 0x00
Reset Value: 0x00000000
The Control Register should only be written to enable the IISC after the chosen configuration has been written to the Mode
Register, in order to avoid unwanted glitches on the IWS, ISCK, and ISDO outputs. The proper sequence is to write the MR
register, then write the CR register to enable the IISC, or to disable the IISC before writing a new value into MR.
• SWRST: Software Reset
Writing a zero to this bit has no effect.
Writing a one to this bit resets all the registers in the module. The module will be disabled after the reset.
This bit always reads as zero.
• TXDIS: Transmitter Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the IISC Transmitter. SR.TXEN will be cleared when the Transmitter is effectively stopped.
• TXEN: Transmitter Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the IISC Transmitter, if TXDIS is not one. SR.TXEN will be set when the Transmitter is effectively
started.
• CKDIS: Clocks Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the IISC clocks generation.
• CKEN: Clocks Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the IISC clocks generation, if CKDIS is not one.
• RXDIS: Receiver Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the IISC Receiver. SR.TXEN will be cleared when the Transmitter is effectively stopped.
• RXEN: Receiver Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the IISC Receiver, if RXDIS is not one. SR.RXEN will be set when the Receiver is effectively
started.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
SWRST - TXDIS TXEN CKDIS CKEN RXDIS RXEN
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24.8.2 Mode Register
Name: MR
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
The Mode Register should only be written when the IISC is stopped, in order to avoid unwanted glitches on the IWS, ISCK,
and ISDO outputs. The proper sequence is to write the MR register, then write the CR register to enable the IISC, or to disable
the IISC before writing a new value into MR.
• IWS24: IWS TDM Slot Width
0: IWS slot is 32-bit wide for DATALENGTH=18/20/24-bit
1: IWS slot is 24-bit wide for DATALENGTH=18/20/24-bit
Refer to Table 24-2, “Slot Length,” on page 595.
• IMCKMODE: Master Clock Mode
0: No Master Clock generated (generic clock is used as ISCK output)
1: Master Clock generated (generic clock is used as IMCK output)
Warning: if IMCK frequency is the same as ISCK, IMCKMODE should not be written as one. Refer to Section 24.6.5 ”Serial
Clock and Word Select Generation” on page 595 and Table 24-2, “Slot Length,” on page 595.
• IMCKFS: Master Clock to fs Ratio
Master Clock frequency is 16*(IMCKFS+1) times the sample rate, i.e. IWS frequency:
31 30 29 28 27 26 25 24
IWS24 IMCKMODE IMCKFS
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- TXSAME TXDMA TXMONO RXLOOP RXDMA RXMONO
76543210
- - - DATALENGTH - MODE
Table 24-4. Master Clock to Sample Frequency (fs) Ratio
fs Ratio IMCKFS
16 fs 0
32 fs 1
48fs 2
64 fs 3
96fs 5
128 fs 7
192fs 11
256 fs 15
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• TXSAME: Transmit Data when Underrun
0: Zero sample transmitted when underrun
1: Previous sample transmitted when underrun
• TXDMA: Single or multiple DMA Channels for Transmitter
0: Transmitter uses a single DMA channel for both audio channels
1: Transmitter uses one DMA channel per audio channel
• TXMONO: Transmit Mono
0: Stereo
1: Mono, with left audio samples duplicated to right audio channel by the IISC
• RXLOOP: Loop-back Test Mode
0: Normal mode
1: ISDO output of IISC is internally connected to ISDI input
• RXMONO: Receive Mono
0: Stereo
1: Mono, with left audio samples duplicated to right audio channel by the IISC
• RXDMA: Single or multiple DMA Channels for Receiver
0: Receiver uses a single DMA channel for both audio channels
1: Receiver uses one DMA channel per audio channel-
• DATALENGTH: Data Word Length
• MODE: Mode
384 fs 23
512 fs 31
768 fs 47
1024 fs 63
Table 24-5. Data Word Length
DATALENGTH Word Length Comments
0 32 bits
1 24 bits
2 20 bits
3 18 bits
4 16 bits
5 16 bits compact stereo Left sample in bits 15 through 0 and right sample in bits 31 through 16 of the same word
6 8 bits
7 8 bits compact stereo Left sample in bits 7 through 0 and right sample in bits 15 through 8 of the same word
Table 24-6. Mode
MODE Comments
0 SLAVE ISCK and IWS pin inputs used as Bit Clock and Word Select/Frame Sync.
1 MASTER Bit Clock and Word Select/Frame Sync generated by IISC from GCLK_IISC and output to ISCK and IWS pins.
GCLK_IISC is output as Master Clock on IMCK if MR.IMCKMODE is one.
Table 24-4. Master Clock to Sample Frequency (fs) Ratio
fs Ratio IMCKFS
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24.8.3 Status Register
Name: SR
Access Type: Read-only
Offset: 0x08
Reset Value: 0x00000000
• TXURCH: Transmit Underrun Channel
This field is cleared when SCR.TXUR is written to one
Bit i of this field is set when a transmit underrun error occurred in channel i (i=0 for first channel of the frame)
• RXORCH: Receive Overrun Channel
This field is cleared when SCR.RXOR is written to one
Bit i of this field is set when a receive overrun error occurred in channel i (i=0 for first channel of the frame)
• TXUR: Transmit Underrun
This bit is cleared when the corresponding bit in SCR is written to one
This bit is set when an underrun error occurs on the THR register or when the corresponding bit in SSR is written to one
• TXRDY: Transmit Ready
This bit is cleared when data is written to THR
This bit is set when the THR register is empty and can be written with new data to be transmitted
• TXEN: Transmitter Enabled
This bit is cleared when the Transmitter is effectively disabled, following a CR.TXDIS or CR.SWRST request
This bit is set when the Transmitter is effectively enabled, following a CR.TXEN request
• RXOR: Receive Overrun
This bit is cleared when the corresponding bit in SCR is written to one
This bit is set when an overrun error occurs on the RHR register or when the corresponding bit in SSR is written to one
• RXRDY: Receive Ready
This bit is cleared when the RHR register is read
This bit is set when received data is present in the RHR register
• RXEN: Receiver Enabled
This bit is cleared when the Receiver is effectively disabled, following a CR.RXDIS or CR.SWRST request
This bit is set when the Receiver is effectively enabled, following a CR.RXEN request
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - TXURCH - - - -
15 14 13 12 11 10 9 8
- - - - - - RXORCH
76543210
- TXUR TXRDY TXEN - RXOR RXRDY RXEN
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24.8.4 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x0C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - TXURCH - - - -
15 14 13 12 11 10 9 8
- - - - - - RXORCH
76543210
- TXUR - - - RXOR - -
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24.8.5 Status Set Register
Name: SSR
Access Type: Write-only
Offset: 0x10
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in SR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - TXURCH - - - -
15 14 13 12 11 10 9 8
- - - - - - RXORCH
76543210
- TXUR - - - RXOR - -
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24.8.6 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- TXUR TXRDY - - RXOR RXRDY -
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24.8.7 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x18
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- TXUR TXRDY - - RXOR RXRDY -
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24.8.8 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- TXUR TXRDY - - RXOR RXRDY -
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24.8.9 Receive Holding Register
Name: RHR
Access Type: Read-only
Offset: 0x20
Reset Value: 0x00000000
• RHR: Received Word
This field is set by hardware to the last received data word. If MR.DATALENGTH specifies less than 32 bits, data shall be rightjustified
into the RHR field.
31 30 29 28 27 26 25 24
RHR[31:24]
23 22 21 20 19 18 17 16
RHR[23:16]
15 14 13 12 11 10 9 8
RHR[15:8]
76543210
RHR[7:0]
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24.8.10 Transmit Holding Register
Name: THR
Access Type: Write-only
Offset: 0x24
Reset Value: 0x00000000
• THR: Data Word to Be Transmitted
Next data word to be transmitted after the current word if TXRDY is not set. If MR.DATALENGTH specifies less than 32 bits, data
shall be right-justified into the THR field.
31 30 29 28 27 26 25 24
THR[31:24]
23 22 21 20 19 18 17 16
THR[23:16]
15 14 13 12 11 10 9 8
THR[15:8]
76543210
THR[7:0]
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24.8.11 Module Version
Name: VERSION
Access Type: Read-only
Offset: 0x28
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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24.8.12 Module Parameters
Name: PARAMETER
Access Type: Read-only
Offset: 0x2C
Reset Value: -
Reserved. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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24.9 Module configuration
The specific configuration for each IISC instance is listed in the following tables. The module bus
clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 24-7. IISC Clocks
Clock Name Description
CLK_IISC Clock for the IISC bus interface
GCLK The generic clock used for the IISC is GCLK6
Table 24-8. Register Reset Values
Register Reset Value
VERSION 0x00000100
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25. Pulse Width Modulation Controller (PWMA)
Rev: 2.0.1.0
25.1 Features
• Left-aligned non-inverted 12-bit PWM
• Common 12-bit timebase counter
– Asynchronous clock source supported
– Spread-spectrum counter to allow a constantly varying duty cycle
• Separate 12-bit duty cycle register per channel
• Synchronized channel updates
– No glitches when changing the duty cycles
• Interlinked operation supported
– Up to 32 channels can be updated with the same duty cycle value at a time
– Up to 4 channels can be updated with different duty cycle values at a time
• Interrupt on PWM timebase overflow
• Incoming peripheral events supported
– Pre-defined channels support incoming (increase/decrease) peripheral events from the
Peripheral Event System
– Incoming increase/decrease event can either increase or decrease the duty cycle by one
• One output peripheral event supported
– Connected to channel 0 and asserted when the common timebase counter is equal to the
programmed duty cycle for channel 0
• Output PWM waveforms
– Support normal waveform output for each channel
– Support composite waveform generation (XOR’ed) for each pair channels
• Open drain driving on selected pins for 5V PWM operation
25.2 Overview
The Pulse Width Modulation Controller (PWMA) controls several pulse width modulation (PWM)
channels. The number of channels is specific to the device. Each channel controls one square
output PWM waveform. Characteristics of the output PWM waveforms such as period and duty
cycle are configured through the user interface. All user interface registers are mapped on the
peripheral bus.
The duty cycle value for each channel can be set independently, while the period is determined
by a common timebase counter (TC). The timebase for the counter is selected by using the allocated
asynchronous Generic Clock (GCLK). The user interface for the PWMA contains
handshake and synchronizing logic to ensure that no glitches occur on the output PWM waveforms
while changing the duty cycle values.
PWMA duty cycle values can be changed using two approaches, either an interlinked singlevalue
mode or an interlinked multi-value mode. In the interlinked single-value mode, any set of
channels, up to 32 channels, can be updated simultaneously with the same value while the other
channels remain unchanged. There is also an interlinked multi-value mode, where the 8 least
significant bits of up to 4 channels can be updated with 4 different values while the other channels
remain unchanged.
Some pins can be driven in open drain mode, allowing the PWMA to generate a 5V waveform
using an external pullup resistor.
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25.3 Block Diagram
Figure 25-1. PWMA Block Diagram
25.4 I/O Lines Description
Each channel outputs one PWM waveform on one external I/O line.
25.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
PWM Blocks
Channel m
Channel 1
Channel 0
Duty Cycle
Register
COMP
PWMA[m:0]
Interrupt
Handling
IRQ
PB
TOP
Timebase
Counter
SPREAD
Adjust
TOFL
READY
Channel_0
CLK_PWMA
GCLK Domain
PB Clock Domain
Spread
Spectrum
Counter
Sync
GCLK ETV
Control
Duty Cycle Channel
Select WAVEXOR
CWG
TCLR CHERR
Table 25-1. I/O Line Description
Pin Name Pin Description Type
PWMA[n] Output PWM waveform for one channel n Output
PWMMOD[n] Output PWM waveform for one channel n, open drain mode Output
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25.5.1 I/O Lines
The pins used for interfacing the PWMA may be multiplexed with I/O Controller lines. The programmer
must first program the I/O Controller to assign the desired PWMA pins to their
peripheral function.
It is only required to enable the PWMA outputs actually in use.
25.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the PWMA, the PWMA will stop
functioning and resume operation after the system wakes up from sleep mode.
25.5.3 Clocks
The clock for the PWMA bus interface (CLK_PWMA) is controlled by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable
the PWMA before disabling the clock, to avoid freezing the PWMA in an undefined state.
Additionally, the PWMA depends on a dedicated Generic Clock (GCLK). The GCLK can be set
to a wide range of frequencies and clock sources and must be enabled in the System Control
Interface (SCIF) before the PWMA can be used.
25.5.4 Interrupts
The PWMA interrupt request lines are connected to the interrupt controller. Using the PWMA
interrupts requires the interrupt controller to be programmed first.
25.5.5 Peripheral Events
The PWMA peripheral events are connected via the Peripheral Event System. Refer to the
Peripheral Event System chapter for details.
25.5.6 Debug Operation
When an external debugger forces the CPU into debug mode, the PWMA continues normal
operation. If the PWMA is configured in a way that requires it to be periodically serviced by the
CPU through interrupts, improper operation or data loss may result during debugging.
25.6 Functional Description
The PWMA embeds a number of PWM channel submodules, each providing an output PWM
waveform. Each PWM channel contains a duty cycle register and a comparator. A common
timebase counter for all channels determines the frequency and the period for all the PWM
waveforms.
25.6.1 Enabling the PWMA
Once the GCLK has been enabled, the PWMA is enabled by writing a one to the EN bit in the
Control Register (CR).
25.6.2 Timebase Counter
The top value of the timebase counter defines the period of the PWMA output waveform. The
timebase counter starts at zero when the PWMA is enabled and counts upwards until it reaches
its effective top value (ETV). The effective top value is defined by specifying the desired number
of GCLK clock cycles in the TOP field of Top Value Register (TVR.TOP) in normal operation (the
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SPREAD field of CR (CR.SPREAD) is zero). When the timebase counter reaches its effective
top value, it restarts counting from zero. The period of the PWMA output waveform is then:
The timebase counter can be reset by writing a one to the Timebase Clear bit in CR (CR.TCLR).
Note that this can cause a glitch to the output PWM waveforms in use.
25.6.3 Spread Spectrum Counter
The spread spectrum counter allows the generation of constantly varying duty cycles on the output
PWM waveforms. This is achieved by varying the effective top value of the timebase counter
in a range defined by the spread spectrum counter value.
When CR.SPREAD is not zero, the spread spectrum counter is enabled. Its range is defined by
CR.SPREAD. It starts to count from -CR.SPREAD when the PWMA is enabled or after reset
and counts upwards. When it reaches CR.SPREAD, it restarts to count from -CR.SPREAD
again. The spread spectrum counter will cause the effective top value to vary from TOPSPREAD
to TOP+SPREAD. Figure 25-2 on page 618 illustrates this. This leads to a constantly
varying duty cycle on the PWM output waveforms though the duty cycle values stored are
unchanged.
Figure 25-2. PWMA Adjusting Top Value for Timebase Counter
25.6.3.1 Special considerations
The maximum value of the timebase counter is 0x0FFF. If SPREAD is written to a value that will
cause the ETV to exceed this value, the spread spectrum counter’s range will be limited to prevent
the timebase counter to exceed its maximum value.
If SPREAD is written to a value causing (TOP-SPREAD) to be below zero, the spread spectrum
counter’s range will be limited to prevent the timebase counter to count below zero.
In both cases, the SPREAD value read from the Control Register will be the same value as written
to the SPREAD field.
TPWMA ETV + 1 TGCLK =
0x0
0x0FFF
Duty Cycle
-SPREAD
SPREAD
TOP Adjusting top value range
for the timerbase counter
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When writing a one to CR.TCLR, the timebase counter and the spread spectrum counter are
reset at their lower limit values and the effective top value of the timebase counter will also be
reset.
25.6.4 Duty Cycle and Waveform Properties
Each PWM channel has its own duty cycle value (DCV) which is write-only and cannot be read
out. The duty cycle value can be changed in two approaches as described in Section25.6.6.
When the duty cycle value is zero, the PWM output is zero. Otherwise, the PWM output is set
when the timebase counter is zero, and cleared when the timebase counter reaches the duty
cycle value. This is summarized as:
Note that when increasing the duty cycle value for one channel from 0 to 1, the number of GCLK
cycles when the PWM waveform is high will jump from 0 to 2. When incrementing the duty cycle
value by one for any other values, the number of GCLK cycle when the waveform is high will
increase by one. This is summarized in Table 25-2.
25.6.5 Waveform Output
PWMA waveforms are output to I/O lines. The output waveform properties are controlled by
Composite Waveform Generation (CWG) register(s). If this register is cleared (by default), the
channel waveforms are out directly to the I/O lines. To avoid too many I/O toggling simultaneously
on the output I/O lines, every other output PWM waveform toggles on the negative edge of
the GCLK instead of the positive edge.
In CWG mode, all channels are paired and their outputs are XOR’ed together if the corresponding
bit of CWG register is set. The even number of output is the XOR’ed output and the odd
number of output is the inverse of its. Each bit of CWG register controls one pair channels and
the least significant bit refers to the lowest number of pair channels.
25.6.6 Updating Duty Cycle Values
25.6.6.1 Interlinked Single Value PWM Operation
The PWM channels can be interlinked to allow multiple channels to be updated simultaneously
with the same duty cycle value. This value must be written to the Interlinked Single Value Duty
Table 25-2. PMW Waveform Duty Cycles
Duty Cycle Value
#Clock Cycles
When Waveform is High
#Clock Cycles
When Waveform is Low
0 0 ETV+1
1 2 ETV-1
2 3 ETV-2
... ... ...
ETV-1 ETV 1
ETV ETV+1 0
PWM Waveform = low when DCV = 0 or TC DCV
high when TC DCV and DCV 0
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(ISDUTY) register. Each channel has a corresponding enabling bit in the Interlinked Single
Value Channel Set (ISCHSET) register(s). When a bit is written to one in the ISCHSET register,
the duty cycle register for the corresponding channel will be updated with the value stored in the
ISDUTY register. It can only be updated when the READY bit in the Status Register
(SR.READY) is one, indicating that the PWMA is ready for writing. Figure 25-3 on page 620
shows the writing procedure. It is thus possible to update the duty cycle values for up to 32 PWM
channels within one ISCHSET register at a time.
Figure 25-3. Interlinked Single Value PWM Operation Flow
25.6.6.2 Interlinked Multiple Value PWM Operation
The interlinked multiple value PWM operation allows up to four channels to be updated simultaneously
with different duty cycle values. The four duty cycle values are required to be written to
the four registers, DUTY3, DUTY2, DUTY1 and DUTY0 , respectively. The index number of the
four channels to be updated is written to the four SEL fields in the Interlinked Multiple Value
Channel Select (IMCHSEL) register (IMCHSEL.SEL). When the IMCHSEL register is written,
the values stored in the DUTY0/1/2/3 registers are synchronized to the duty cycle registers for
the channels selected by the SEL fields. Figure 25-4 on page 620 shows the writing procedure.
Note that only writes to the implemented channels will be effective. If one of the IMCHSEL.SEL
fields points to a non-existing channel, the corresponding value in the DUTYx register will not be
written. If the same channel is specified multiple times in the IMCHSEL.SEL fields, the channel
will be updated with the value referred by the upper IMCHSEL.SEL field.
When only the least significant 8-bits duty cycle value are considered for updating, the four duty
cycle values can be written to the IMDUTY register once. This is equivalent to writing the four
duty cycle values to the four DUTY registers one by one.
Figure 25-4. Interlinked Multiple Value PWM Operation Flow
ISCHSETm
...
Write
Enable
Channeln
DUTY
Channel1
DUTY
Channel0
DUTY
ISDUTY
Channel2
DUTY
DUTY3/2/1/0
IMDUTY IMCHSEL
Channeln
DUTY
...
MUX
Channel1
DUTY
Channel0
DUTY
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25.6.7 Open Drain Mode
Some pins can be used in open drain mode, allowing the PWMA waveform to toggle between
0V and up to 5V on these pins. In this mode the PWMA will drive the pin to zero or leave the output
open. An external pullup can be used to pull the pin up to the desired voltage.
To enable open drain mode on a pin the PWMAOD function must be selected instead of the
PWMA function in the I/O Controller. Please refer to the Module Configuration chapter for information
about which pins are available in open drain mode.
25.6.8 Synchronization
Both the timebase counter and the spread spectrum counter can be reset and the duty cycle
registers can be written through the user interface of the module. This requires a synchronization
between the PB and GCLK clock domains, which takes a few clock cycles of each clock
domain. The BUSY bit in SR indicates when the synchronization is ongoing. Writing to the module
while the BUSY bit is set will result in discarding the new value.
Note that the duty cycle registers will not be updated with the new values until the timebase
counter reaches its top value, in order to avoid glitches. The BUSY bit in SR will always be set
during this updating and synchronization period.
25.6.9 Interrupts
When the timebase counter overflows, the Timebase Overflow bit in the Status Register
(SR.TOFL) is set. If the corresponding bit in the Interrupt Mask Register (IMR) is set, an interrupt
request will be generated.
Since the user needs to wait until the user interface is available between each write due to synchronization,
a READY bit is provided in SR, which can be used to generate an interrupt
request.
The interrupt request will be generated if the corresponding bit in IMR is set. Bits in IMR are set
by writing a one to the corresponding bit in the Interrupt Enable Register (IER), and cleared by
writing a one to the corresponding bit in the Interrupt Disable Register (IDR). The interrupt
request remains active until the corresponding bit in SR is cleared by writing a one to the corresponding
bit in the Status Clear Register (SCR).
25.6.10 Peripheral Events
25.6.10.1 Input Peripheral Events
The pre-defined channels support input peripheral events from the Peripheral Event System.
Input peripheral events must be enabled by writing a one to the corresponding bit in the Channel
Event Enable Registers (CHEERs) before peripheral events can be used to control the duty
cycle value. Each bit in the register corresponds to one channel, where bit 0 corresponds to
channel 0 and so on. Both the increase and decrease events are enabled for the corresponding
channel when a bit in the CHEER register is set.
An increase or decrease event (event_incr/event_decr) can either increase or decrease the duty
cycle value by one in a PWM period. The events are taken into account when the common timebase
counter reaches its top. The behavior is defined by the Channel Event Response Register
(CHERR). Each bit in the register corresponds to one channel, where bit 0 corresponds to channel
0 and so on. If the bit in CHERR is set to 0 (default) for a channel, the increase event will
increase the duty cycle value and the decrease event will decrease the duty cycle value for that
channel. If the bit is set to 1, the increase and decrease event will have reverse function so that
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the increase event will decrease the duty cycle value and decrease event will increase the duty
cycle value. If both the increase event and the decrease event occur at the same time for a
channel, the duty cycle value will not be changed.
The number of channels supporting input peripheral events is device specific. Please refer to the
Module Configuration section at the end of this chapter for details.
25.6.10.2 Output Peripheral Event
The PWMA also supports one output peripheral event (event_ch0) to the Peripheral Event System.
This output peripheral event is connected to channel 0 and will be asserted when the
timebase counter reaches the duty cycle value for channel 0. This output event is always
enabled.
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25.7 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 25-3. PWMA Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Read/Write 0x00000000
0x04 Interlinked Single Value Duty Register ISDUTY Write-only 0x00000000
0x08 Interlinked Multiple Value Duty Register IMDUTY Write-only 0x00000000
0x0C Interlinked Multiple Value Channel Select IMCHSEL Write-only 0x00000000
0x10 Interrupt Enable Register IER Write-only 0x00000000
0x14 Interrupt Disable Register IDR Write-only 0x00000000
0x18 Interrupt Mask Register IMR Read-only 0x00000000
0x1C Status Register SR Read-only 0x00000000
0x20 Status Clear Register SCR Write-only 0x00000000
0x24 Parameter Register PARAMETER Read-only - (1)
0x28 Version Register VERSION Read-only - (1)
0x2C Top Value Register TVR Read/Write 0x00000000
0x30+m*0x10 Interlinked Single Value Channel Set m ISCHSETm Write-only 0x00000000
0x34+m*0x10 Channel Event Response Register m CHERRm Read/Write 0x00000000
0x38+m*0x10 Channel Event Enable Register m CHEERm Read/Write 0x00000000
0x3C+k*0x10 CWG Register CWGk Read/Write 0x00000000
0x80 Interlinked Multiple Value Duty0 Register DUTY0 Write-only 0x00000000
0x84 Interlinked Multiple Value Duty1 Register DUTY1 Write-only 0x00000000
0x88 Interlinked Multiple Value Duty2 Register DUTY2 Write-only 0x00000000
0x8C Interlinked Multiple Value Duty3 Register DUTY3 Write-only 0x00000000
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25.7.1 Control Register
Name: CR
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• SPREAD: Spread Spectrum Limit Value
The spread spectrum limit value, together with the TOP field, defines the range for the spread spectrum counter. It is introduced
in order to achieve constant varying duty cycles on the output PWM waveforms. Refer to Section25.6.3 for more information.
• TOP: Timebase Counter Top Value
The top value for the timebase counter. The value written to this field will update the least significant 8 bits of the TVR.TOP field
in case only 8-bits resolution is required. The 4 most significant bits of TVR.TOP will be written to 0. When the TVR.TOP field is
written, this CR.TOP field will also be updated with only the least significant 8 bits of TVR.TOP field.
• TCLR: Timebase Clear
Writing a zero to this bit has no effect.
Writing a one to this bit will clear the timebase counter.
This bit is always read as zero.
• EN: Module Enable
0: The PWMA is disabled
1: The PWMA is enabled
31 30 29 28 27 26 25 24
- - - - - - - SPREAD[8]
23 22 21 20 19 18 17 16
SPREAD[7:0]
15 14 13 12 11 10 9 8
TOP
76543210
- - - - - - TCLR EN
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25.7.2 Interlinked Single Value Duty Register
Name: ISDUTY
Access Type: Write-only
Offset: 0x04
Reset Value: 0x00000000
• DUTY: Duty Cycle Value
The duty cycle value written to this field is written simultaneously to all channels selected in the ISCHSETm register.
If the value zero is written to DUTY all affected channels will be disabled. In this state the output waveform will be zero all the
time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - DUTY[11:8]
76543210
DUTY[7:0]
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25.7.3 Interlinked Multiple Value Duty Register
Name: IMDUTY
Access Type: Write-only
Offset: 0x08
Reset Value: 0x00000000
• DUTYn: Duty Cycle
The value written to DUTY field n will be automatically written to the least significant 8 bits of the DUTYn register for a PWMA
channel while the most significant 4bits of the DUTYn register are unchanged. Which channel is selected for updating is defined
by the corresponding SEL field in the IMCHSEL register.
To write mulitple channels at a time with more than 8 bits of the duty cycle value, refer to DUTY3/2/1/0 registers.
If the value zero is written to DUTY all affected channels will be disabled. In this state the output waveform will be zero all the
time.
31 30 29 28 27 26 25 24
DUTY3
23 22 21 20 19 18 17 16
DUTY2
15 14 13 12 11 10 9 8
DUTY1
76543210
DUTY0
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25.7.4 Interlinked Multiple Value Channel Select
Name: IMCHSEL
Access Type: Write-only
Offset: 0x0C
Reset Value: 0x00000000
• SELn: Channel Select
The duty cycle of the PWMA channel SELn will be updated with the value stored in the DUTYn register when IMCHSEL is
written. If SELn points to a non-implemented channel, the write will be discarded.
Note: The duty registers will be updated with the value stored in the DUTY3, DUTY2, DUTY1 and DUTY0 registers when the IMCHSEL
register is written. Synchronization takes place immediately when an IMCHSEL register is written. The duty cycle registers
will, however, not be updated until the synchronization is completed and the timebase counter reaches its top value in order to
avoid glitches. When only 8 bits duty cycle value are considered for updating, the four duty cycle values can be written to the
IMDUTY register once. This is equivalent to writing the 8 bits four duty cycle values to the four DUTY registers one by one while
the upper 4 bits remain unchanged.
31 30 29 28 27 26 25 24
SEL3
23 22 21 20 19 18 17 16
SEL2
15 14 13 12 11 10 9 8
SEL1
76543210
SEL0
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25.7.5 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x10
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - READY - TOFL
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25.7.6 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - READY - TOFL
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25.7.7 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - READY - TOFL
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25.7.8 Status Register
Name: SR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
• BUSY: Interface Busy
This bit is automatically cleared when the interface is no longer busy.
This bit is set when the user interface is busy and will not respond to new write operations.
• READY: Interface Ready
This bit is cleared by writing a one to the corresponding bit in the SCR register.
This bit is set when the BUSY bit has a 1-to-0 transition.
• TOFL: Timebase Overflow
This bit is cleared by writing a one to corresponding bit in the SCR register.
This bit is set when the timebase counter has wrapped at its top value.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - BUSY READY - TOFL
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25.7.9 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
This register always reads as zero.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 1 10 9 8
--------
76543210
- - - - - READY - TOFL
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25.7.10 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x24
Reset Value: -
• CHANNELS: Channels Implemented
This field contains the number of channels implemented on the device.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
CHANNELS
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25.7.11 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x28
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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25.7.12 Top Value Register
Name: TVR
Access Type: Read/Write
Offset: 0x2C
Reset Value: 0x00000000
• TOP: Timebase Counter Top Value
The top value for the timebase counter. The value written to the CR.TOP field will automatically be written to the 8 least
significant bits of this field while the 4 most significant bits will be 0. When this register is written, it will also automatically update
the CR.TOP field with the 8 least significant bits.
The effective top value of the timebase counter is defined by both TVR.TOP and the CR.SPREAD. Refer to Section25.6.2 for
more information.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - TOP[11:8]
76543210
TOP[7:0]
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25.7.13 Interlinked Single Value Channel Set
Name: ISCHSETm
Access Type: Write-only
Offset: 0x30+m*0x10
Reset Value: 0x00000000
• SET: Single Value Channel Set
If the bit n in SET is one, the duty cycle of PWMA channel n will be updated with the value written to ISDUTY.
If more than one ISCHSET register is present, ISCHSET0 controls channels 31 to 0 and ISCHSET1 controls channels 63 to 32.
Note: The duty registers will be updated with the value stored in the ISDUTY register when any ISCHSETm register is written. Synchronization
takes place immediately when an ISCHSET register is written. The duty cycle registers will, however, not be
updated until the synchronization is completed and the timebase counter reaches its top value in order to avoid glitches.
31 30 29 28 27 26 25 24
SET
23 22 21 20 19 18 17 16
SET
15 14 13 12 11 10 9 8
SET
76543210
SET
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25.7.14 Channel Event Response Register
Name: CHERRm
Access Type: Read/Write
Offset: 0x34+m*0x10
Reset Value: 0x00000000
• CHER: Channel Event Response
0: The increase event will increase the duty cycle value by one in a PWM period for the corresponding channel and the
decrease event will decrease the duty cycle value by one.
1: The increase event will decrease the duty cycle value by one in a PWM period for the corresponding channel and the
decrease event will increase the duty cycle value by one.
The events are taken into account when the common timebase counter reaches its top.
If more than one CHERR register is present, CHERR0 controls channels 31-0 and CHERR1 controls channels 64-32 and so on.
31 30 29 28 27 26 25 24
CHER
23 22 21 20 19 18 17 16
CHER
15 14 13 12 11 10 9 8
CHER
76543210
CHER
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25.7.15 Channel Event Enable Register
Name: CHEERm
Access Type: Read/Write
Offset: 0x38+m*0x10
Reset Value: 0x00000000
• CHEE: Channel Event Enable
0: The input peripheral event for the corresponding channel is disabled.
1: The input peripheral event for the corresponding channel is enabled.
Both increase and decrease events for channel n are enabled if bit n is one.
If more than one CHEER register is present, CHEER0 controls channels 31-0 and CHEER1 controls channels 64-32 and so on.
31 30 29 28 27 26 25 24
CHEE
23 22 21 20 19 18 17 16
CHEE
15 14 13 12 11 10 9 8
CHEE
76543210
CHEE
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25.7.16 Composite Waveform Generation
Name: CWG
Access Type: Read/Write
Offset: 0x3C+k*0x10
Reset Value: 0x00000000
• XOR: Pair Waveform XOR’ed
If the bit n in XOR field is one, the pair of PWMA output waveforms will be XORed before output. The even number output will be
the XOR’ed output and the odd number output will be reverse of it. For example, if bit 0 in XOR is one, the pair of PWMA output
waveforms for channel 0 and 1 will be XORed together.
If bit n in XOR is zero, normal waveforms are output for that pair. Note that
If more than one CWG register is present, CWG0 controls the first 32 pairs, corresponding to channels 63 downto 0, and CWG1
controls the second 32 pairs, corresponding to channels 127 downto 64.
31 30 29 28 27 26 25 24
XOR
23 22 21 20 19 18 17 16
XOR
15 14 13 12 11 10 9 8
XOR
76543210
XOR
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25.7.17 Interlinked Multiple Value Duty0/1/2/3 Register
Name: DUTY0/1/2/3
Access Type: Write-only
Offset: 0x80-0x8C
Reset Value: 0x00000000
These registers allows up to 4 channels to be updated with a common 12-bits duty cycle value at a time. They are the
extension of the IMDUTY register which only supports updating the least significant 8 bits of the duty registers for up to 4
channels.
• DUTY: Duty Cycle Value
The duty cycle value written to this field will be updated to the channel specified by IMCHSEL.
DUTY0 is specified by IMCHSEL.SEL0, DUTY1 is specified by IMCHSEL.SEL1, and so on.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - DUTY[11:8]
76543210
DUTY[7:0]
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25.8 Module Configuration
The specific configuration for each PWMA instance is listed in the following tables. The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 25-4. PWMA Configuration
Feature PWMA
Number of PWM channels 36
Channels supporting incoming peripheral events 0, 6, 8, 9, 11, 14, 19, and 20
PWMA channels with Open Drain mode 21, 27, and 28
Table 25-5. PWMA Clocks
Clock Name Descripton
CLK_PWMA Clock for the PWMA bus interface
GCLK The generic clock used for the PWMA is GCLK3
Table 25-6. Register Reset Values
Register Reset Value
VERSION 0x00000201
PARAMETER 0x00000024
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26. Timer/Counter (TC)
Rev: 2.2.3.1.3
26.1 Features
• Three 16-bit Timer Counter channels
• A wide range of functions including:
– Frequency measurement
– Event counting
– Interval measurement
– Pulse generation
– Delay timing
– Pulse width modulation
– Up/down capabilities
• Each channel is user-configurable and contains:
– Three external clock inputs
– Five internal clock inputs
– Two multi-purpose input/output signals
• Internal interrupt signal
• Two global registers that act on all three TC channels
• Peripheral event input on all A lines in capture mode
26.2 Overview
The Timer Counter (TC) includes three identical 16-bit Timer Counter channels.
Each channel can be independently programmed to perform a wide range of functions including
frequency measurement, event counting, interval measurement, pulse generation, delay timing,
and pulse width modulation.
Each channel has three external clock inputs, five internal clock inputs, and two multi-purpose
input/output signals which can be configured by the user. Each channel drives an internal interrupt
signal which can be programmed to generate processor interrupts.
The TC block has two global registers which act upon all three TC channels.
The Block Control Register (BCR) allows the three channels to be started simultaneously with
the same instruction.
The Block Mode Register (BMR) defines the external clock inputs for each channel, allowing
them to be chained.
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26.3 Block Diagram
Figure 26-1. TC Block Diagram
26.4 I/O Lines Description
26.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
26.5.1 I/O Lines
The pins used for interfacing the compliant external devices may be multiplexed with I/O lines.
The user must first program the I/O Controller to assign the TC pins to their peripheral functions.
I/O
Controller
TC2XC2S
INT0
INT1
INT2
TIOA0
TIOA1
TIOA2
TIOB0
TIOB1
TIOB2
XC2
TCLK0
TCLK1
TCLK2
TCLK0
TCLK1
TCLK2
TCLK0
TCLK1
TCLK2
TIOA1
TIOA2
TIOA0
TIOA2
TIOA1
Interrupt
Controller
CLK0
CLK1
CLK2
A0
B0
A1
B1
A2
B2
Timer Count er
TIOB
TIOA
TIOB
SYNC
TIMER_CLOCK1
TIOA
SYNC
SYNC
TIOA
TIOB
TIMER_CLOCK2
TIMER_CLOCK3
TIMER_CLOCK4
TIMER_CLOCK5
XC1
XC0
XC0
XC2
XC1
XC0
XC1
XC2
Timer/Counter
Channel 2
Timer/Counter
Channel 1
Timer/Counter
Channel 0
TC1XC1S
TC0XC0S
TIOA0
Table 26-1. I/O Lines Description
Pin Name Description Type
CLK0-CLK2 External Clock Input Input
A0-A2 I/O Line A Input/Output
B0-B2 I/O Line B Input/Output
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When using the TIOA lines as inputs the user must make sure that no peripheral events are generated
on the line. Refer to the Peripheral Event System chapter for details.
26.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the TC, the TC will stop functioning
and resume operation after the system wakes up from sleep mode.
26.5.3 Clocks
The clock for the TC bus interface (CLK_TC) is generated by the Power Manager. This clock is
enabled at reset, and can be disabled in the Power Manager. It is recommended to disable the
TC before disabling the clock, to avoid freezing the TC in an undefined state.
26.5.4 Interrupts
The TC interrupt request line is connected to the interrupt controller. Using the TC interrupt
requires the interrupt controller to be programmed first.
26.5.5 Peripheral Events
The TC peripheral events are connected via the Peripheral Event System. Refer to the Peripheral
Event System chapter for details.
26.5.6 Debug Operation
The Timer Counter clocks are frozen during debug operation, unless the OCD system keeps
peripherals running in debug operation.
26.6 Functional Description
26.6.1 TC Description
The three channels of the Timer Counter are independent and identical in operation. The registers
for channel programming are listed in Figure 26-3 on page 659.
26.6.1.1 Channel I/O Signals
As described in Figure 26-1 on page 643, each Channel has the following I/O signals.
26.6.1.2 16-bit counter
Each channel is organized around a 16-bit counter. The value of the counter is incremented at
each positive edge of the selected clock. When the counter has reached the value 0xFFFF and
passes to 0x0000, an overflow occurs and the Counter Overflow Status bit in the Channel n Status
Register (SRn.COVFS) is set.
Table 26-2. Channel I/O Signals Description
Block/Channel Signal Name Description
Channel Signal
XC0, XC1, XC2 External Clock Inputs
TIOA Capture mode: Timer Counter Input
Waveform mode: Timer Counter Output
TIOB Capture mode: Timer Counter Input
Waveform mode: Timer Counter Input/Output
INT Interrupt Signal Output
SYNC Synchronization Input Signal
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The current value of the counter is accessible in real time by reading the Channel n Counter
Value Register (CVn). The counter can be reset by a trigger. In this case, the counter value
passes to 0x0000 on the next valid edge of the selected clock.
26.6.1.3 Clock selection
At block level, input clock signals of each channel can either be connected to the external inputs
TCLK0, TCLK1 or TCLK2, or be connected to the configurable I/O signals A0, A1 or A2 for
chaining by writing to the BMR register. See Figure 26-2 on page 645.
Each channel can independently select an internal or external clock source for its counter:
• Internal clock signals: TIMER_CLOCK1, TIMER_CLOCK2, TIMER_CLOCK3,
TIMER_CLOCK4, TIMER_CLOCK5. See the Module Configuration Chapter for details about
the connection of these clock sources.
• External clock signals: XC0, XC1 or XC2. See the Module Configuration Chapter for details
about the connection of these clock sources.
This selection is made by the Clock Selection field in the Channel n Mode Register
(CMRn.TCCLKS).
The selected clock can be inverted with the Clock Invert bit in CMRn (CMRn.CLKI). This allows
counting on the opposite edges of the clock.
The burst function allows the clock to be validated when an external signal is high. The Burst
Signal Selection field in the CMRn register (CMRn.BURST) defines this signal.
Note: In all cases, if an external clock is used, the duration of each of its levels must be longer than the
CLK_TC period. The external clock frequency must be at least 2.5 times lower than the CLK_TC.
Figure 26-2. Clock Selection
TIMER_CLOCK5
XC2
TCCLKS
CLKI
BURST
1
Selected
Clock
XC1
XC0
TIMER_CLOCK4
TIMER_CLOCK3
TIMER_CLOCK2
TIMER_CLOCK1
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26.6.1.4 Clock control
The clock of each counter can be controlled in two different ways: it can be enabled/disabled
and started/stopped. See Figure 26-3 on page 646.
• The clock can be enabled or disabled by the user by writing to the Counter Clock
Enable/Disable Command bits in the Channel n Clock Control Register (CCRn.CLKEN and
CCRn.CLKDIS). In Capture mode it can be disabled by an RB load event if the Counter Clock
Disable with RB Loading bit in CMRn is written to one (CMRn.LDBDIS). In Waveform mode,
it can be disabled by an RC Compare event if the Counter Clock Disable with RC Compare
bit in CMRn is written to one (CMRn.CPCDIS). When disabled, the start or the stop actions
have no effect: only a CLKEN command in CCRn can re-enable the clock. When the clock is
enabled, the Clock Enabling Status bit is set in SRn (SRn.CLKSTA).
• The clock can also be started or stopped: a trigger (software, synchro, external or compare)
always starts the clock. In Capture mode the clock can be stopped by an RB load event if the
Counter Clock Stopped with RB Loading bit in CMRn is written to one (CMRn.LDBSTOP). In
Waveform mode it can be stopped by an RC compare event if the Counter Clock Stopped
with RC Compare bit in CMRn is written to one (CMRn.CPCSTOP). The start and the stop
commands have effect only if the clock is enabled.
Figure 26-3. Clock Control
26.6.1.5 TC operating modes
Each channel can independently operate in two different modes:
• Capture mode provides measurement on signals.
• Waveform mode provides wave generation.
The TC operating mode selection is done by writing to the Wave bit in the CCRn register
(CCRn.WAVE).
In Capture mode, TIOA and TIOB are configured as inputs.
Q S
R
S
R
Q
CLKSTA CLKEN CLKDIS
Stop
Event
Disable
Counter
Clock
Selected
Clock Trigger
Event
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In Waveform mode, TIOA is always configured to be an output and TIOB is an output if it is not
selected to be the external trigger.
26.6.1.6 Trigger
A trigger resets the counter and starts the counter clock. Three types of triggers are common to
both modes, and a fourth external trigger is available to each mode.
The following triggers are common to both modes:
• Software Trigger: each channel has a software trigger, available by writing a one to the
Software Trigger Command bit in CCRn (CCRn.SWTRG).
• SYNC: each channel has a synchronization signal SYNC. When asserted, this signal has the
same effect as a software trigger. The SYNC signals of all channels are asserted
simultaneously by writing a one to the Synchro Command bit in the BCR register
(BCR.SYNC).
• Compare RC Trigger: RC is implemented in each channel and can provide a trigger when the
counter value matches the RC value if the RC Compare Trigger Enable bit in CMRn
(CMRn.CPCTRG) is written to one.
The channel can also be configured to have an external trigger. In Capture mode, the external
trigger signal can be selected between TIOA and TIOB. In Waveform mode, an external event
can be programmed to be one of the following signals: TIOB, XC0, XC1, or XC2. This external
event can then be programmed to perform a trigger by writing a one to the External Event Trigger
Enable bit in CMRn (CMRn.ENETRG).
If an external trigger is used, the duration of the pulses must be longer than the CLK_TC period
in order to be detected.
Regardless of the trigger used, it will be taken into account at the following active edge of the
selected clock. This means that the counter value can be read differently from zero just after a
trigger, especially when a low frequency signal is selected as the clock.
26.6.1.7 Peripheral events on TIOA inputs
The TIOA input lines are ored internally with peripheral events from the Peripheral Event System.
To capture using events the user must ensure that the corresponding pin functions for the
TIOA line are disabled. When capturing on the external TIOA pin the user must ensure that no
peripheral events are generated on this pin.
26.6.2 Capture Operating Mode
This mode is entered by writing a zero to the CMRn.WAVE bit.
Capture mode allows the TC channel to perform measurements such as pulse timing, frequency,
period, duty cycle and phase on TIOA and TIOB signals which are considered as
inputs.
Figure 26-4 on page 649 shows the configuration of the TC channel when programmed in Capture
mode.
26.6.2.1 Capture registers A and B
Registers A and B (RA and RB) are used as capture registers. This means that they can be
loaded with the counter value when a programmable event occurs on the signal TIOA.
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The RA Loading Selection field in CMRn (CMRn.LDRA) defines the TIOA edge for the loading of
the RA register, and the RB Loading Selection field in CMRn (CMRn.LDRB) defines the TIOA
edge for the loading of the RB register.
RA is loaded only if it has not been loaded since the last trigger or if RB has been loaded since
the last loading of RA.
RB is loaded only if RA has been loaded since the last trigger or the last loading of RB.
Loading RA or RB before the read of the last value loaded sets the Load Overrun Status bit in
SRn (SRn.LOVRS). In this case, the old value is overwritten.
26.6.2.2 Trigger conditions
In addition to the SYNC signal, the software trigger and the RC compare trigger, an external trigger
can be defined.
The TIOA or TIOB External Trigger Selection bit in CMRn (CMRn.ABETRG) selects TIOA or
TIOB input signal as an external trigger. The External Trigger Edge Selection bit in CMRn
(CMRn.ETREDG) defines the edge (rising, falling or both) detected to generate an external trigger.
If CMRn.ETRGEDG is zero (none), the external trigger is disabled.
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Figure 26-4. Capture Mode TIMER_CLOCK1 XC0
XC1
XC2
TCCLKS
CLKI
Q S
R
S
R
Q
CLKSTA CLKEN CLKDIS
BURST
TIOB
Capture
Register A Compare RC =
16-bit
Counter
ABETRG
SWTRG
ETRGEDG CPCTRG
IMR
Trig
LDRBS
LDRAS
ETRGS
SR
LOVRS
COVFS
SYNC
1
MTIOB
TIOA
MTIOA
LDRA
LDBSTOP
If RA is not Loaded
or RB is Loaded If RA is Loaded
LDBDIS
CPCS
INT
Edge
Detector
LDRB
CLK OVF
RESET
Timer/Counter Channel
Edge
Detector
Edge
Detector
Capture
Register B
Register C
TIMER_CLOCK2
TIMER_CLOCK3
TIMER_CLOCK4
TIMER_CLOCK5
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26.6.3 Waveform Operating Mode
Waveform operating mode is entered by writing a one to the CMRn.WAVE bit.
In Waveform operating mode the TC channel generates one or two PWM signals with the same
frequency and independently programmable duty cycles, or generates different types of oneshot
or repetitive pulses.
In this mode, TIOA is configured as an output and TIOB is defined as an output if it is not used
as an external event.
Figure 26-5 on page 651 shows the configuration of the TC channel when programmed in
Waveform operating mode.
26.6.3.1 Waveform selection
Depending on the Waveform Selection field in CMRn (CMRn.WAVSEL), the behavior of CVn
varies.
With any selection, RA, RB and RC can all be used as compare registers.
RA Compare is used to control the TIOA output, RB Compare is used to control the TIOB output
(if correctly configured) and RC Compare is used to control TIOA and/or TIOB outputs.
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Figure 26-5. Waveform Mode TCCLKS CLKI Q S
R
S
R
Q
CLKSTA CLKEN CLKDIS
CPCDIS
BURST
TIOB
Register A
Compare RC =
CPCSTOP
16-bit
Counter
EEVT
EEVTEDG
SYNC
SWTRG
ENETRG
WAVSEL
IMR
Trig
ACPC
ACPA
AEEVT
ASWTRG
BCPC
BCPB
BEEVT
BSWTRG
TIOA
MTIOA
TIOB
MTIOB
CPAS
COVFS
ETRGS
SR
CPCS
CPBS
CLK
OVF
RESET
Output Contr oller O utput Cont r oller
INT
1
Edge
Detector
Timer/Counter Channel
TIMER_CLOCK1
XC0
XC1
XC2
WAVSEL
Register B Register C
Compare RB = Compare RA =
TIMER_CLOCK2
TIMER_CLOCK3
TIMER_CLOCK4
TIMER_CLOCK5
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26.6.3.2 WAVSEL = 0
When CMRn.WAVSEL is zero, the value of CVn is incremented from 0 to 0xFFFF. Once
0xFFFF has been reached, the value of CVn is reset. Incrementation of CVn starts again and
the cycle continues. See Figure 26-6 on page 652.
An external event trigger or a software trigger can reset the value of CVn. It is important to note
that the trigger may occur at any time. See Figure 26-7 on page 653.
RC Compare cannot be programmed to generate a trigger in this configuration. At the same
time, RC Compare can stop the counter clock (CMRn.CPCSTOP = 1) and/or disable the counter
clock (CMRn.CPCDIS = 1).
Figure 26-6. WAVSEL= 0 Without Trigger
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter cleared by compare match with
0xFFFF
0xFFFF
Waveform Examples
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Figure 26-7. WAVSEL= 0 With Trigger
26.6.3.3 WAVSEL = 2
When CMRn.WAVSEL is two, the value of CVn is incremented from zero to the value of RC,
then automatically reset on a RC Compare. Once the value of CVn has been reset, it is then
incremented and so on. See Figure 26-8 on page 654.
It is important to note that CVn can be reset at any time by an external event or a software trigger
if both are programmed correctly. See Figure 26-9 on page 654.
In addition, RC Compare can stop the counter clock (CMRn.CPCSTOP) and/or disable the
counter clock (CMRn.CPCDIS = 1).
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter cleared by compare match with 0xFFFF
0xFFFF
Waveform Examples
Counter cleared by trigger
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Figure 26-8. WAVSEL = 2 Without Trigger
Figure 26-9. WAVSEL = 2 With Trigger
26.6.3.4 WAVSEL = 1
When CMRn.WAVSEL is one, the value of CVn is incremented from 0 to 0xFFFF. Once 0xFFFF
is reached, the value of CVn is decremented to 0, then re-incremented to 0xFFFF and so on.
See Figure 26-10 on page 655.
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter cleared by compare match
with RC
0xFFFF
Waveform Examples
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter cleared by compare match with RC
0xFFFF
Waveform Examples
Counter cleared by trigger
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A trigger such as an external event or a software trigger can modify CVn at any time. If a trigger
occurs while CVn is incrementing, CVn then decrements. If a trigger is received while CVn is
decrementing, CVn then increments. See Figure 26-11 on page 655.
RC Compare cannot be programmed to generate a trigger in this configuration.
At the same time, RC Compare can stop the counter clock (CMRn.CPCSTOP = 1) and/or disable
the counter clock (CMRn.CPCDIS = 1).
Figure 26-10. WAVSEL = 1 Without Trigger
Figure 26-11. WAVSEL = 1 With Trigger
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter decremented by compare match
with 0xFFFF
0xFFFF
Waveform Examples
Time
Counter Value
TIOB
TIOA
Counter decremented by compare match with 0xFFFF
0xFFFF
Waveform Examples
Counter decremented by trigger
RC
RB
RA
Counter incremented by trigger
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26.6.3.5 WAVSEL = 3
When CMRn.WAVSEL is three, the value of CVn is incremented from zero to RC. Once RC is
reached, the value of CVn is decremented to zero, then re-incremented to RC and so on. See
Figure 26-12 on page 656.
A trigger such as an external event or a software trigger can modify CVn at any time. If a trigger
occurs while CVn is incrementing, CVn then decrements. If a trigger is received while CVn is
decrementing, CVn then increments. See Figure 26-13 on page 657.
RC Compare can stop the counter clock (CMRn.CPCSTOP = 1) and/or disable the counter clock
(CMRn.CPCDIS = 1).
Figure 26-12. WAVSEL = 3 Without Trigger
Time
Counter Value
RC
RB
RA
TIOB
TIOA
Counter cleared by compare match with RC
0xFFFF
Waveform Examples
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Figure 26-13. WAVSEL = 3 With Trigger
26.6.3.6 External event/trigger conditions
An external event can be programmed to be detected on one of the clock sources (XC0, XC1,
XC2) or TIOB. The external event selected can then be used as a trigger.
The External Event Selection field in CMRn (CMRn.EEVT) selects the external trigger. The
External Event Edge Selection field in CMRn (CMRn.EEVTEDG) defines the trigger edge for
each of the possible external triggers (rising, falling or both). If CMRn.EEVTEDG is written to
zero, no external event is defined.
If TIOB is defined as an external event signal (CMRn.EEVT = 0), TIOB is no longer used as an
output and the compare register B is not used to generate waveforms and subsequently no
IRQs. In this case the TC channel can only generate a waveform on TIOA.
When an external event is defined, it can be used as a trigger by writing a one to the
CMRn.ENETRG bit.
As in Capture mode, the SYNC signal and the software trigger are also available as triggers. RC
Compare can also be used as a trigger depending on the CMRn.WAVSEL field.
26.6.3.7 Output controller
The output controller defines the output level changes on TIOA and TIOB following an event.
TIOB control is used only if TIOB is defined as output (not as an external event).
The following events control TIOA and TIOB:
• software trigger
• external event
• RC compare
RA compare controls TIOA and RB compare controls TIOB. Each of these events can be programmed
to set, clear or toggle the output as defined in the following fields in CMRn:
• RC Compare Effect on TIOB (CMRn.BCPC)
Time
Counter Value
TIOB
TIOA
Counter decremented by compare match
with RC
0xFFFF
Waveform Examples
RC
RB
RA
Counter decremented by trigger
Counter incremented by trigger
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• RB Compare Effect on TIOB (CMRn.BCPB)
• RC Compare Effect on TIOA (CMRn.ACPC)
• RA Compare Effect on TIOA (CMRn.ACPA)
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26.7 User Interface
Table 26-3. TC Register Memory Map
Offset Register Register Name Access Reset
0x00 Channel 0 Control Register CCR0 Write-only 0x00000000
0x04 Channel 0 Mode Register CMR0 Read/Write 0x00000000
0x10 Channel 0 Counter Value CV0 Read-only 0x00000000
0x14 Channel 0 Register A RA0 Read/Write(1) 0x00000000
0x18 Channel 0 Register B RB0 Read/Write(1) 0x00000000
0x1C Channel 0 Register C RC0 Read/Write 0x00000000
0x20 Channel 0 Status Register SR0 Read-only 0x00000000
0x24 Interrupt Enable Register IER0 Write-only 0x00000000
0x28 Channel 0 Interrupt Disable Register IDR0 Write-only 0x00000000
0x2C Channel 0 Interrupt Mask Register IMR0 Read-only 0x00000000
0x40 Channel 1 Control Register CCR1 Write-only 0x00000000
0x44 Channel 1 Mode Register CMR1 Read/Write 0x00000000
0x50 Channel 1 Counter Value CV1 Read-only 0x00000000
0x54 Channel 1 Register A RA1 Read/Write(1) 0x00000000
0x58 Channel 1 Register B RB1 Read/Write(1) 0x00000000
0x5C Channel 1 Register C RC1 Read/Write 0x00000000
0x60 Channel 1 Status Register SR1 Read-only 0x00000000
0x64 Channel 1 Interrupt Enable Register IER1 Write-only 0x00000000
0x68 Channel 1 Interrupt Disable Register IDR1 Write-only 0x00000000
0x6C Channel 1 Interrupt Mask Register IMR1 Read-only 0x00000000
0x80 Channel 2 Control Register CCR2 Write-only 0x00000000
0x84 Channel 2 Mode Register CMR2 Read/Write 0x00000000
0x90 Channel 2 Counter Value CV2 Read-only 0x00000000
0x94 Channel 2 Register A RA2 Read/Write(1) 0x00000000
0x98 Channel 2 Register B RB2 Read/Write(1) 0x00000000
0x9C Channel 2 Register C RC2 Read/Write 0x00000000
0xA0 Channel 2 Status Register SR2 Read-only 0x00000000
0xA4 Channel 2 Interrupt Enable Register IER2 Write-only 0x00000000
0xA8 Channel 2 Interrupt Disable Register IDR2 Write-only 0x00000000
0xAC Channel 2 Interrupt Mask Register IMR2 Read-only 0x00000000
0xC0 Block Control Register BCR Write-only 0x00000000
0xC4 Block Mode Register BMR Read/Write 0x00000000
0xF8 Features Register FEATURES Read-only -(2)
0xFC Version Register VERSION Read-only -(2)
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Notes: 1. Read-only if CMRn.WAVE is zero.
2. The reset values are device specific. Please refer to the Module Configuration section at the
end of this chapter.
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26.7.1 Channel Control Register
Name: CCR
Access Type: Write-only
Offset: 0x00 + n * 0x40
Reset Value: 0x00000000
• SWTRG: Software Trigger Command
1: Writing a one to this bit will perform a software trigger: the counter is reset and the clock is started.
0: Writing a zero to this bit has no effect.
• CLKDIS: Counter Clock Disable Command
1: Writing a one to this bit will disable the clock.
0: Writing a zero to this bit has no effect.
• CLKEN: Counter Clock Enable Command
1: Writing a one to this bit will enable the clock if CLKDIS is not one.
0: Writing a zero to this bit has no effect.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - SWTRG CLKDIS CLKEN
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26.7.2 Channel Mode Register: Capture Mode
Name: CMR
Access Type: Read/Write
Offset: 0x04 + n * 0x40
Reset Value: 0x00000000
• LDRB: RB Loading Selection
• LDRA: RA Loading Selection
• WAVE
1: Capture mode is disabled (Waveform mode is enabled).
0: Capture mode is enabled.
• CPCTRG: RC Compare Trigger Enable
1: RC Compare resets the counter and starts the counter clock.
0: RC Compare has no effect on the counter and its clock.
• ABETRG: TIOA or TIOB External Trigger Selection
1: TIOA is used as an external trigger.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - LDRB LDRA
15 14 13 12 11 10 9 8
WAVE CPCTRG - - - ABETRG ETRGEDG
76543210
LDBDIS LDBSTOP BURST CLKI TCCLKS
LDRB Edge
0 none
1 rising edge of TIOA
2 falling edge of TIOA
3 each edge of TIOA
LDRA Edge
0 none
1 rising edge of TIOA
2 falling edge of TIOA
3 each edge of TIOA
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0: TIOB is used as an external trigger.
• ETRGEDG: External Trigger Edge Selection
• LDBDIS: Counter Clock Disable with RB Loading
1: Counter clock is disabled when RB loading occurs.
0: Counter clock is not disabled when RB loading occurs.
• LDBSTOP: Counter Clock Stopped with RB Loading
1: Counter clock is stopped when RB loading occurs.
0: Counter clock is not stopped when RB loading occurs.
• BURST: Burst Signal Selection
• CLKI: Clock Invert
1: The counter is incremented on falling edge of the clock.
0: The counter is incremented on rising edge of the clock.
• TCCLKS: Clock Selection
ETRGEDG Edge
0 none
1 rising edge
2 falling edge
3 each edge
BURST Burst Signal Selection
0 The clock is not gated by an external signal
1 XC0 is ANDed with the selected clock
2 XC1 is ANDed with the selected clock
3 XC2 is ANDed with the selected clock
TCCLKS Clock Selected
0 TIMER_CLOCK1
1 TIMER_CLOCK2
2 TIMER_CLOCK3
3 TIMER_CLOCK4
4 TIMER_CLOCK5
5 XC0
6 XC1
7 XC2
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26.7.3 Channel Mode Register: Waveform Mode
Name: CMR
Access Type: Read/Write
Offset: 0x04 + n * 0x40
Reset Value: 0x00000000
• BSWTRG: Software Trigger Effect on TIOB
• BEEVT: External Event Effect on TIOB
31 30 29 28 27 26 25 24
BSWTRG BEEVT BCPC BCPB
23 22 21 20 19 18 17 16
ASWTRG AEEVT ACPC ACPA
15 14 13 12 11 10 9 8
WAVE WAVSEL ENETRG EEVT EEVTEDG
76543210
CPCDIS CPCSTOP BURST CLKI TCCLKS
BSWTRG Effect
0 none
1 set
2 clear
3 toggle
BEEVT Effect
0 none
1 set
2 clear
3 toggle
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• BCPC: RC Compare Effect on TIOB
• BCPB: RB Compare Effect on TIOB
• ASWTRG: Software Trigger Effect on TIOA
• AEEVT: External Event Effect on TIOA
• ACPC: RC Compare Effect on TIOA
BCPC Effect
0 none
1 set
2 clear
3 toggle
BCPB Effect
0 none
1 set
2 clear
3 toggle
ASWTRG Effect
0 none
1 set
2 clear
3 toggle
AEEVT Effect
0 none
1 set
2 clear
3 toggle
ACPC Effect
0 none
1 set
2 clear
3 toggle
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• ACPA: RA Compare Effect on TIOA
• WAVE
1: Waveform mode is enabled.
0: Waveform mode is disabled (Capture mode is enabled).
• WAVSEL: Waveform Selection
• ENETRG: External Event Trigger Enable
1: The external event resets the counter and starts the counter clock.
0: The external event has no effect on the counter and its clock. In this case, the selected external event only controls the TIOA
output.
• EEVT: External Event Selection
Note: 1. If TIOB is chosen as the external event signal, it is configured as an input and no longer generates waveforms and subsequently
no IRQs.
• EEVTEDG: External Event Edge Selection
• CPCDIS: Counter Clock Disable with RC Compare
1: Counter clock is disabled when counter reaches RC.
0: Counter clock is not disabled when counter reaches RC.
ACPA Effect
0 none
1 set
2 clear
3 toggle
WAVSEL Effect
0 UP mode without automatic trigger on RC Compare
1 UPDOWN mode without automatic trigger on RC Compare
2 UP mode with automatic trigger on RC Compare
3 UPDOWN mode with automatic trigger on RC Compare
EEVT Signal selected as external event TIOB Direction
0 TIOB input(1)
1 XC0 output
2 XC1 output
3 XC2 output
EEVTEDG Edge
0 none
1 rising edge
2 falling edge
3 each edge
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• CPCSTOP: Counter Clock Stopped with RC Compare
1: Counter clock is stopped when counter reaches RC.
0: Counter clock is not stopped when counter reaches RC.
• BURST: Burst Signal Selection
• CLKI: Clock Invert
1: Counter is incremented on falling edge of the clock.
0: Counter is incremented on rising edge of the clock.
• TCCLKS: Clock Selection
BURST Burst Signal Selection
0 The clock is not gated by an external signal.
1 XC0 is ANDed with the selected clock.
2 XC1 is ANDed with the selected clock.
3 XC2 is ANDed with the selected clock.
TCCLKS Clock Selected
0 TIMER_CLOCK1
1 TIMER_CLOCK2
2 TIMER_CLOCK3
3 TIMER_CLOCK4
4 TIMER_CLOCK5
5 XC0
6 XC1
7 XC2
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26.7.4 Channel Counter Value Register
Name: CV
Access Type: Read-only
Offset: 0x10 + n * 0x40
Reset Value: 0x00000000
• CV: Counter Value
CV contains the counter value in real time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
CV[15:8]
76543210
CV[7:0]
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26.7.5 Channel Register A
Name: RA
Access Type: Read-only if CMRn.WAVE = 0, Read/Write if CMRn.WAVE = 1
Offset: 0x14 + n * 0X40
Reset Value: 0x00000000
• RA: Register A
RA contains the Register A value in real time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
RA[15:8]
76543210
RA[7:0]
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26.7.6 Channel Register B
Name: RB
Access Type: Read-only if CMRn.WAVE = 0, Read/Write if CMRn.WAVE = 1
Offset: 0x18 + n * 0x40
Reset Value: 0x00000000
• RB: Register B
RB contains the Register B value in real time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
RB[15:8]
76543210
RB[7:0]
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26.7.7 Channel Register C
Name: RC
Access Type: Read/Write
Offset: 0x1C + n * 0x40
Reset Value: 0x00000000
• RC: Register C
RC contains the Register C value in real time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
RC[15:8]
76543210
RC[7:0]
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26.7.8 Channel Status Register
Name: SR
Access Type: Read-only
Offset: 0x20 + n * 0x40
Reset Value: 0x00000000
Note: Reading the Status Register will also clear the interrupt bit for the corresponding interrupts.
• MTIOB: TIOB Mirror
1: TIOB is high. If CMRn.WAVE is zero, this means that TIOB pin is high. If CMRn.WAVE is one, this means that TIOB is driven
high.
0: TIOB is low. If CMRn.WAVE is zero, this means that TIOB pin is low. If CMRn.WAVE is one, this means that TIOB is driven
low.
• MTIOA: TIOA Mirror
1: TIOA is high. If CMRn.WAVE is zero, this means that TIOA pin is high. If CMRn.WAVE is one, this means that TIOA is driven
high.
0: TIOA is low. If CMRn.WAVE is zero, this means that TIOA pin is low. If CMRn.WAVE is one, this means that TIOA is driven
low.
• CLKSTA: Clock Enabling Status
1: This bit is set when the clock is enabled.
0: This bit is cleared when the clock is disabled.
• ETRGS: External Trigger Status
1: This bit is set when an external trigger has occurred.
0: This bit is cleared when the SR register is read.
• LDRBS: RB Loading Status
1: This bit is set when an RB Load has occurred and CMRn.WAVE is zero.
0: This bit is cleared when the SR register is read.
• LDRAS: RA Loading Status
1: This bit is set when an RA Load has occurred and CMRn.WAVE is zero.
0: This bit is cleared when the SR register is read.
• CPCS: RC Compare Status
1: This bit is set when an RC Compare has occurred.
0: This bit is cleared when the SR register is read.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - MTIOB MTIOA CLKSTA
15 14 13 12 11 10 9 8
--------
76543210
ETRGS LDRBS LDRAS CPCS CPBS CPAS LOVRS COVFS
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• CPBS: RB Compare Status
1: This bit is set when an RB Compare has occurred and CMRn.WAVE is one.
0: This bit is cleared when the SR register is read.
• CPAS: RA Compare Status
1: This bit is set when an RA Compare has occurred and CMRn.WAVE is one.
0: This bit is cleared when the SR register is read.
• LOVRS: Load Overrun Status
1: This bit is set when RA or RB have been loaded at least twice without any read of the corresponding register and
CMRn.WAVE is zero.
0: This bit is cleared when the SR register is read.
• COVFS: Counter Overflow Status
1: This bit is set when a counter overflow has occurred.
0: This bit is cleared when the SR register is read.
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26.7.9 Channel Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x24 + n * 0x40
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
ETRGS LDRBS LDRAS CPCS CPBS CPAS LOVRS COVFS
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26.7.10 Channel Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x28 + n * 0x40
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
ETRGS LDRBS LDRAS CPCS CPBS CPAS LOVRS COVFS
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26.7.11 Channel Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x2C + n * 0x40
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
ETRGS LDRBS LDRAS CPCS CPBS CPAS LOVRS COVFS
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26.7.12 Block Control Register
Name: BCR
Access Type: Write-only
Offset: 0xC0
Reset Value: 0x00000000
• SYNC: Synchro Command
1: Writing a one to this bit asserts the SYNC signal which generates a software trigger simultaneously for each of the channels.
0: Writing a zero to this bit has no effect.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - SYNC
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26.7.13 Block Mode Register
Name: BMR
Access Type: Read/Write
Offset: 0xC4
Reset Value: 0x00000000
• TC2XC2S: External Clock Signal 2 Selection
• TC1XC1S: External Clock Signal 1 Selection
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - TC2XC2S TC1XC1S TC0XC0S
TC2XC2S Signal Connected to XC2
0 TCLK2
1 none
2 TIOA0
3 TIOA1
TC1XC1S Signal Connected to XC1
0 TCLK1
1 none
2 TIOA0
3 TIOA2
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• TC0XC0S: External Clock Signal 0 Selection
TC0XC0S Signal Connected to XC0
0 TCLK0
1 none
2 TIOA1
3 TIOA2
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26.7.14 Features Register
Name: FEATURES
Access Type: Read-only
Offset: 0xF8
Reset Value: -
• BRPBHSB: Bridge type is PB to HSB
1: Bridge type is PB to HSB.
0: Bridge type is not PB to HSB.
• UPDNIMPL: Up/down is implemented
1: Up/down counter capability is implemented.
0: Up/down counter capability is not implemented.
• CTRSIZE: Counter size
This field indicates the size of the counter in bits.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
-------
15 14 13 12 11 10 9 8
- - - - - - BRPBHSB UPDNIMPL
76543210
CTRSIZE
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26.7.15 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0xFC
Reset Value: -
• VARIANT: Variant number
Reserved. No functionality associated.
• VERSION: Version number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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26.8 Module Configuration
The specific configuration for each Timer/Counter instance is listed in the following tables.The
module bus clocks listed here are connected to the system bus clocks. Please refer to the Power
Manager chapter for details.
26.8.1 Clock Connections
There are two Timer/Counter modules, TC0 and TC1, with three channels each, giving a total of
six Timer/Counter channels. Each Timer/Counter channel can independently select an internal
or external clock source for its counter:
Table 26-4. TC Bus Interface Clocks
Module name Clock Name Description
TC0 CLK_TC0 Clock for the TC0 bus interface
TC1 CLK_TC1 Clock for the TC1 bus interface
Table 26-5. Timer/Counter Clock Connections
Module Source Name Connection
TC0 Internal TIMER_CLOCK1 32 KHz oscillator clock (CLK_32K)
TIMER_CLOCK2 PBA Clock / 2
TIMER_CLOCK3 PBA Clock / 8
TIMER_CLOCK4 PBA Clock / 32
TIMER_CLOCK5 PBA Clock / 128
External XC0 See Section on page 10
XC1
XC2
TC1 Internal TIMER_CLOCK1 32 KHz oscillator clock (CLK_32K)
TIMER_CLOCK2 PBA Clock / 2
TIMER_CLOCK3 PBA Clock / 8
TIMER_CLOCK4 PBA Clock / 32
TIMER_CLOCK5 PBA Clock / 128
External XC0 See Section on page 10
XC1
XC2
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27. Peripheral Event System
Rev: 1.0.0.1
27.1 Features
• Direct peripheral to peripheral communication system
• Allows peripherals to receive, react to, and send peripheral events without CPU intervention
• Cycle deterministic event communication
• Asynchronous interrupts allow advanced peripheral operation in low power sleep modes
27.2 Overview
Several peripheral modules can be configured to emit or respond to signals known as peripheral
events. The exact condition to trigger a peripheral event, or the action taken upon receiving a
peripheral event, is specific to each module. Peripherals that respond to peripheral events are
called peripheral event users and peripherals that emit peripheral events are called peripheral
event generators. A single module can be both a peripheral event generator and user.
The peripheral event generators and users are interconnected by a network known as the
Peripheral Event System. This allows low latency peripheral-to-peripheral signaling without CPU
intervention, and without consuming system resources such as bus or RAM bandwidth. This
offloads the CPU and system resources compared to a traditional interrupt-based software
driven system.
27.3 Peripheral Event System Block Diagram
Figure 27-1. Peripheral Event System Block Diagram
27.4 Functional Description
27.4.1 Configuration
The Peripheral Event System in the ATUC64/128/256L3/4U has a fixed mapping of peripheral
events between generators and users, as described in Table 27-1 to Table 27-4. Thus, the user
does not need to configure the interconnection between the modules, although each peripheral
event can be enabled or disabled at the generator or user side as described in the peripheral
chapter for each module.
Peripheral
Event
System
Generator
Generator
User
Generator/
User
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Table 27-1. Peripheral Event Mapping from ACIFB to PWMA
Generator Generated Event User Effect Asynchronous
ACIFB channel 0
AC0 VINP > AC0 VINN PWMA channel 0
PWMA duty cycle value increased by one
No
AC0 VINN > AC0 VINP PWMA duty cycle value decreased by one
ACIFB channel 1
AC1 VINP > AC1 VINN PWMA channel 6
PWMA duty cycle value increased by one
AC1 VINN > AC1 VINP PWMA duty cycle value decreased by one
ACIFB channel 2
AC2 VINP > AC2 VINN PWMA channel 8
PWMA duty cycle value increased by one
AC2 VINN > AC2 VINP PWMA duty cycle value decreased by one
ACIFB channel 3
AC3 VINP > AC3 VINN PWMA channel 9
PWMA duty cycle value increased by one
AC3 VINN > AC3 VINP PWMA duty cycle value decreased by one
ACIFB channel 4
AC4 VINP > AC4 VINN PWMA channel 11
PWMA duty cycle value increased by one
AC4 VINN > AC4 VINP PWMA duty cycle value decreased by one
ACIFB channel 5
AC5 VINP > AC5 VINN PWMA channel 14
PWMA duty cycle value increased by one
AC5 VINN > AC5 VINP PWMA duty cycle value decreased by one
ACIFB channel 6
AC6 VINP > AC6 VINN PWMA channel 19
PWMA duty cycle value increased by one
AC6 VINN > AC6 VINP PWMA duty cycle value decreased by one
ACIFB channel 7
AC7 VINP > AC7 VINN PWMA channel 20
PWMA duty cycle value increased by one
AC7 VINN > AC7 VINP PWMA duty cycle value decreased by one
ACIFB channel n ACn VINN > ACn VINP CAT Automatically used by the CAT when
performing QMatrix acquisition. No
Table 27-2. Peripheral Event Mapping from GPIO to TC
Generator Generated Event User Effect Asynchronous
GPIO
Pin change on PA00-PA07
TC0
A0 capture
No
Pin change on PA08-PA15 A1 capture
Pin change on PA16-PA23 A2 capture
Pin change on PB00-PB07 TC1
A1 capture
Pin change on PB08-PB15 A2 capture
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27.4.2 Peripheral Event Connections
Each generated peripheral event is connected to one or more users. If a peripheral event is connected
to multiple users, the peripheral event can trigger actions in multiple modules.
A peripheral event user can likewise be connected to one or more peripheral event generators. If
a peripheral event user is connected to multiple generators, the peripheral events are OR’ed
together to a single peripheral event. This means that peripheral events from either one of the
generators will result in a peripheral event to the user.
To configure a peripheral event, the peripheral event must be enabled at both the generator and
user side. Even if a generator is connected to multiple users, only the users with the peripheral
event enabled will trigger on the peripheral event.
27.4.3 Low Power Operation
As the peripheral events do not require CPU intervention, they are available in Idle mode. They
are also available in deeper sleep modes if both the generator and user remain clocked in that
mode.
Certain events are known as asynchronous peripheral events, as identified in Table 27-1 to
Table 27-4. These can be issued even when the system clock is stopped, and revive unclocked
user peripherals. The clock will be restarted for this module only, without waking the system from
sleep mode. The clock remains active only as long as required by the triggered function, before
being switched off again, and the system remains in the original sleep mode. The CPU and sysTable
27-3. Peripheral Event Mapping from AST
Generator Generated Event User Effect Asynchronous
AST
Overflow event
ACIFB
Comparison is triggered if the ACIFB.CONFn
register is written to 11 (Event Triggered Single
Measurement Mode) and the EVENTEN bit in
the ACIFB.CTRL register is written to 1.
Yes
Periodic event
Alarm event
Overflow event
ADCIFB
Conversion is triggered if the TRGMOD bit in
the ADCIFB.TRGR register is written to 111
(Peripheral Event Trigger).
Periodic event
Alarm event
Overflow event
CAT Trigger one iteration of autonomous touch
detection. Periodic event
Alarm event
Table 27-4. Peripheral Event Mapping from PWMA
Generator Generated Event User Effect Asynchronous
PWMA channel 0
Timebase counter
reaches the duty cycle
value.
ACIFB
Comparison is triggered if the ACIFB.CONFn
register is written to 11 (Event Triggered Single
Measurement Mode) and the EVENTEN bit in
the ACIFB.CTRL register is written to 1. No
ADCIFB
Conversion is triggered if the TRGMOD bit in
the ADCIFB.TRGR register is written to 111
(Peripheral Event Trigger).
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tem will only be woken up if the user peripheral generates an interrupt as a result of the
operation. This concept is known as SleepWalking and is described in further detail in the Power
Manager chapter. Note that asynchronous peripheral events may be associated with a delay
due to the need to restart the system clock source if this has been stopped in the sleep mode.
27.5 Application Example
This application example shows how the Peripheral Event System can be used to program the
ADC Interface to perform ADC conversions at selected intervals.
Conversions of the active analog channels are started with a software or a hardware trigger.
One of the possible hardware triggers is a peripheral event trigger, allowing the Peripheral Event
System to synchronize conversion with some configured peripheral event source. From Table
27-3 and Table 27-4, it can be read that this peripheral event source can be either an AST
peripheral event, or an event from the PWM Controller. The AST can generate periodic peripheral
events at selected intervals, among other types of peripheral events. The Peripheral Event
System can then be used to set up the ADC Interface to sample an analog signal at regular
intervals.
The user must enable peripheral events in the AST and in the ADC Interface to accomplish this.
The periodic peripheral event in the AST is enabled by writing a one to the corresponding bit in
the AST Event Enable Register (EVE). To select the peripheral event trigger for the ADC Interface,
the user must write the value 0x7 to the Trigger Mode (TRGMOD) field in the ADC
Interface Trigger Register (TRGR). When the peripheral events are enabled, the AST will generate
peripheral events at the selected intervals, and the Peripheral Event System will route the
peripheral events to the ADC Interface, which will perform ADC conversions at the selected
intervals.
Figure 27-2. Application Example
Since the AST peripheral event is asynchronous, the description above will also work in sleep
modes where the ADC clock is stopped. In this case, the ADC clock (and clock source, if
needed) will be restarted during the ADC conversion. After the conversion, the ADC clock and
clock source will return to the sleep state, unless the ADC generates an interrupt, which in turn
will wake up the system. Using asynchronous interrupts thus allows ADC operation in much
lower power states than would otherwise be possible.
Peripheral
Event
System
AST ADC
Interface
Trigger
conversion
Periodic peripheral
event
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28. Audio Bit Stream DAC (ABDACB)
Rev.: 1.0.0.0
28.1 Features
• 16 bit digital stereo DAC
• Oversampling D/A conversion architecture
– Adjustable oversampling ratio
– 3rd order Sigma-Delta D/A converters
• Digital bitstream output
• Parallel interface
• Connects to DMA for background transfer without CPU intervention
• Supported sampling frequencies
– 8000Hz, 11025Hz, 12000Hz, 16000Hz, 22050Hz, 24000Hz, 32000Hz, 44100Hz, and 48000Hz
• Supported data formats
– 32-, 24-, 20-, 18-, 16-, and 8-bit stereo format
– 16- and 8-bit compact stereo format, with left and right sample packed in the same word to
reduce data transfers
• Common mode offset control
• Volume control
28.2 Overview
The Audio Bitstream DAC (ABDACB) converts a 16-bit sample value to a digital bitstream with
an average value proportional to the sample value. Two channels are supported making the
Audio Bitstream DAC particularly suitable for stereo audio. Each channel has a pair of complementary
digital outputs, DAC and DACN, which can be connected to an external high input
impedance amplifier.
The Audio Bitstream DAC is made up of several signal processing blocks and a 3rd order Sigma
Delta D/A converter for each channel. The Sigma Delta modulator converts the parallel data to a
bitstream, while the signal processing blocks perform volume control, offset control, upsampling,
and filtering to compensate for the upsampling process. The upsampling is performed by a Cascaded
Integrator-Comb (CIC) filter, and the compensation filter is a Finite Impulse Response
(FIR) CIC compensation filter.
28.3 Block Diagram
Figure 28-1. ABDACB Block Diagram
User Inter af ce
Synchronizer
Volume control
Offset control
CIC Compensation
filter (FIR)
CIC
Comb
Section
CIC Integrator
section
Clock
divider
Sigma Delta
Modulator
Sigma Delta
Modulator
clk_abdacb gclk
Signal processing
(before up-sampling)
CLK
DAC[0]
DACN[0]
DAC[1]
DACN[1]
PB
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28.4 I/O Lines Description
28.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
28.5.1 I/O lines
The output pins used for the output bitstream from the Audio Bitstream DAC may be multiplexed
with I/O Controller lines.
Before using the Audio Bitstream DAC, the I/O Controller must be configured in order for the
Audio Bitstream DAC I/O lines to be in Audio Bitstream DAC peripheral mode.
28.5.2 Clocks
The clock for the ABDACB bus interface (CLK_ABDACB) is generated by the Power Manager.
This clock is turned on by default, and can be enabled and disabled in the Power Manager. It is
recommended to disable the ABDACB before disabling the clock, to avoid freezing the ABDACB
in an undefined state. Before using the Audio Bitstream DAC, the user must ensure that the
Audio Bitstream DAC clock is enabled in the Power Manager.
The Audio Bitstream DAC requires a separate clock for the D/A conversion. This clock is provided
by a generic clock which has to be set up in the System Control Interface (SCIF). The
frequency for this clock has to be set as described in Table 28-3 on page 697. It is important that
this clock is accurate and has low jitter. Incorrect frequency will result in too fast or too slow playback
(frequency shift), and too high jitter will add noise to the D/A conversion. For best
performance one should trade frequency accuracy (within some limits) for low jitter to obtain the
best performance as jitter will have large impact on the quality of the converted signal.
28.5.3 DMA
The ABDACB is connected to the Peripheral DMA controller. Using DMA to transfer data samples
requires the Peripheral DMA controller to be programmed before enabling the ABDACB.
28.5.4 Interrupts
The ABDACB interrupt request line is connected to the interrupt controller. Using the ABDACB
interrupt requires the interrupt controller to be programmed first.
Table 28-1. I/O Lines Description
Pin Name Pin Description Type
DAC[0] Output for channel 0 Output
DACN[0] Inverted output for channel 0 Output
DAC[1] Output for channel 1 Output
DACN[1] Inverted output for channel 1 Output
CLK Clock output for DAC Output
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28.6 Functional Description
28.6.1 Construction
The Audio Bitstream DAC is divided into several parts, the user interface, the signal processing
blocks, and the Sigma Delta modulator blocks. See Figure 28-1 on page 687. The user interface
is used to configure the signal processing blocks and to input new data samples to the converter.The
signal processing blocks manages volume control, offset control, and upsampling.
The Sigma Delta blocks converts the parallel data to1-bit bitstreams.
28.6.1.1 CIC Interpolation Filter
The interpolation filter in the system is a Cascaded Integrator-Comb (CIC) interpolation filter
which interpolates from Fs to {125, 128, 136}xFs depending on the control settings. This filter is a
4th order CIC filter, and the basic building blocks of the filter is a comb part and an integrator
part. Since the CIC interpolator has a sinc-function frequency response it is compensated by a
linear phase CIC compensation filter to make the passband response more flat in the range 0-
20kHz, see figure Figure 28-4 on page 693. The frequency response of this type of interpolator
has the first zero at the input sampling frequency. This means that the first repeated specters
created by the upsampling process will not be fully rejected and the output signal will contain signals
from these repeated specters. See Figure 28-6 on page 694.
Since the human ear can not hear frequencies above 20kHz, we should not be affected by this
when the sample rate is above 40kHz, but digital measurement equipment will be affected. This
need to be accounted for when doing measurements on the system to prevent aliasing and
incorrect measurement results.
28.6.1.2 Sigma Delta Modulator
The Sigma Delta modulator is a 3rd order modulator consisting of three differentiators (delta
blocks), three integrators (sigma blocks), and a one bit quantizer. The purpose of the integrators
is to shape the noise, so that the noise is reduced in the audio passband and increased at the
higher frequencies, where it can be filtered out by an analog low-pass filter. To be able to filter
out all the noise at high frequencies the analog low-pass filter must be one order larger than the
Sigma Delta modulator.
28.6.1.3 Recreating the Analog Signal
Since the DAC and DACN outputs from the ABDAC are digital square wave signals, they have
to be passed through a low pass filter to recreate the analog signal. This also means that noise
on the IO voltage will couple through to the analog signal. To remove some of the IO noise the
ABDAC can output a clock signal, CLK, which can be used to resample the DAC and DACN signals
on external Flip-Flops powered by a clean supply.
28.6.2 Initialization
Before enabling the ABDACB the correct configuration must be applied to the Control Register
(CR). Configuring the Alternative Upsampling Ratio bit (CR.ALTUPR), Common Mode Offset
Control bit (CR.CMOC), and the Sampling Frequency field (CR.FS) according to the sampling
rate of the data that is converted and the type of amplifier the outputs are connected to is
required to get the correct behavior of the system. When the correct configuration is applied the
ABDACB can be enabled by writing a one to the Enable bit in the Control Register (CR.EN). The
module is disabled by writing a zero to the Enable bit. The module should be disabled before
entering sleep modes to ensure that the outputs are not left in an undesired state.
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28.6.3 Basic operation
To convert audio data to a digital bitstream the user must first initialize the ABDACB as
described in Section 28.6.2. When the ABDACB is initialized and enabled it will indicate that it is
ready to receive new data by setting the Transmit Ready bit in the Status Register (SR.TXRDY).
When the TXRDY bit is set in the Status Register the user has to write new samples to Sample
Data Register 0 (SDR0) and Sample Data Register 1 (SDR1). If the Mono Mode (MONO) bit in
the Control Register (CR) is set, or one of the compact stereo formats are used by configuring
the Data Word Format (DATAFORMAT) in the Control Register, only SDR0 has to be written.
Failing to write to the sample data registers will result in an underrun indicated by the Transmit
Underrun (TXUR) bit in the Status Register (SR.TXUR). When new samples are written to the
sample data registers the TXRDY bit will be cleared.
To increase performance of the system an interrupt handler or DMA transfer can be used to
write new samples to the sample data registers. See Section 28.6.10 for details on DMA, and
Section 28.6.11 for details on interrupt.
28.6.4 Data Format
The input data type is two’s complement. The Audio Bitstream DAC can be configured to accept
different audio formats. The format must be configured in the Data Word Format field in the Control
Register. In regular operation data for the two channels are written to the sample data
registers SDR0 and SDR1. If the data format field specifies a format using less than 32 bits, data
must be written right-justified in SDR0 and SDR1. Sign extension into the unused bits is not necessary.
Only the 16 most significant bits in the data will be used by the ABDACB. For data
formats larger than 16 bits the least significant bits are ignored. For 8-bit data formats the 8 bits
will be used as the most significant bits in the 16-bit samples, the additional bits will be zeros.
The ABDACB also supports compact data formats for 16- and 8-bit samples. For 16-bit samples
the sample for channel 0 must be written to bits 15 through 0 and the sample for channel 1 must
be written to bits 31 through 16 in SDR0. For 8-bit samples the sample for channel 0 must be
written to bits 7 through 0 and the sample for channel 1 must be written to bits 15 through 8 in
SDR0. SDR1 is not used in this mode. See Table 28-5 on page 699.
28.6.5 Data Swapping
When the Swap Channels (SWAP) bit in the Control Register (CR.SWAP) is one, writing to the
Sample Data Register 0 (SDR0) will put the data in Sample Data Register 1 (SDR1). Writing
SDR1 will put the data in SDR0. If one of the two compact stereo formats is used the lower and
upper halfword of SDR0 will be swapped when writing to SDR0.
28.6.6 Common Mode Offset Control
When the Common Mode Offset Control (CMOC) bit in the Control Register is one the input data
will get a DC value applied to it and the amplitude will be scaled. This will make the common
mode offset of the two corresponding outputs, DAC and DACN, to move away from each other
so that the output signals are not overlapping. The result is that the two signals can be applied to
a differential analog filter, and the difference will always be a positive value, removing the need
for a negative voltage supply for the filter. The cost of doing this a 3dB loss in dynamic range. On
the left side of Figure 28-2 one can see the filtered output from the DAC and DACN pins when a
sine wave is played when CR.CMOC is zero. The waveform on the right side shows the output
of the differential filter when the two outputs on the left side are used as inputs to the differential
filter. Figure 28-3 show the corresponding outputs when CR.CMOC is one.
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Figure 28-2. Output signals with CMOC=0
Figure 28-3. Output signals with CMOC=1
28.6.7 Volume Control
The Audio Bitstream DAC have two volume control registers, Volume Control Register 0 (VCR0)
and Volume Control Register 1 (VCR1), that can be used to adjust the volume for the corresponding
channel. The volume control is linear and will only scale each sample according to the
value in the Volume Control (VOLUME) field in the volume control registers. The register also
has a Mute bit (MUTE) which can be used to mute the corresponding channel. The filtered out-
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put of the DAC pins will have a voltage given by the following equation, given that it is configured
to run at the default upsampling ratio of 128:
If one want to get coherence between the sign of the input data and the output voltage one can
use the DATAN outputs or invert the sign of the input data by software.
28.6.8 Mono
When the Mono bit (MONO) in the Control Register is set, data written to SDR0 will be used for
both output channels. If one of the compact stereo formats are used only the data written to the
part of SDR0 that corresponds with channel 0 is used.
28.6.9 Alternative Upsampling Ratio
The digital filters and Sigma Delta modulators requires its own clock to perform the conversion at
the correct speed, and this clock is provided by a generic clock in the SCIF. The frequency of
this clock depends on the input sample rate and the upsampling ratio which is controlled by the
Alternative Upsampling Ratio bit (ALTUPR) in the Control Register.
The ABDACB supports three upsampling ratios, 125, 128, and 136. The default setting is a ratio
of 128, and is used when CR.ALTUPR is zero. Using this ratio gives a clock frequency requirement
that is common for audio products. In some cases one may want to use other clock
frequencies that already are available in the system. By writing a one to CR.ALTUPR a upsampling
ratio of 125 or 136 is used depending on the configuration of the Sampling Frequency field
in the Control Register. Refer to Table 28-3 for required clock frequency and settings.
The required clock frequency of the generic clock can be calculated from the following equation:
R is the upsampling ratio of the converter. If CR.ALTUPR is zero the upsampling ratio is 128. If
CR.ALTUPR is one, R will change to 125 when CR.FS is configured for 8kHz, 12kHz, 16kHz,
24kHz, 32kHz, and 48kHz. For the other configurations of CR.FS, 11.025kHz, 22.050kHz, and
44.100kHz, it will change to 136.
28.6.10 DMA operation
The Audio Bitstream DAC is connected to the Peripheral DMA Controller. The Peripheral DMA
Controller can be programmed to automatically transfer samples to the Sample Data Registers
(SDR0 and SDR1) when the Audio Bitstream DAC is ready for new samples. Two DMA channels
are used, one for each sample data register. If the Mono Mode bit in the Control Register
(CR.MONO) is one, or one of the compact stereo formats is used, only the DMA channel connected
to SDR0 will be used. When using DMA only the Control Register needs to be written in
the Audio Bitstream DAC. This enables the Audio Bitstream DAC to operate without any CPU
intervention such as polling the Status Register (SR) or using interrupts. See the Peripheral
DMA Controller documentation for details on how to setup Peripheral DMA transfers.
28.6.11 Interrupts
The ABDACB requires new data samples at a rate of FS. The interrupt status bits are used to
indicate when the system is ready to receive new samples. The Transmit Ready Interrupt Status
bit in the Status Register (SR.TXRDY) will be set whenever the ABDACB is ready to receive a
new sample. A new sample value must be written to the sample data registers (SDR0 and
VOUT
1
2
-- 33
128 – --------- SDR
215 ------------ VOLUME
215 – 1
------------------------ VVDDIO =
GCLK[Hz] F = S R 8
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SDR1) before 1/FS second, or an underrun will occur, as indicated by the Underrun Interrupt bit
in SR (SR.TXUR). The interrupt bits in SR are cleared by writing a one to the corresponding bit
in the Status Clear Register (SCR).
28.6.12 Frequency Response
Figure Figure 28-4 to Figure 28-7 show the frequency response for the system. The sampling
frequency used is 48kHz, but the response will be the same for other sampling frequencies,
always having the first zero at FS.
Figure 28-4. Passband Frequency Response
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Figure 28-5. Frequency Response up to Sampling Frequency
Figure 28-6. Frequency Response up to 3x Sampling Frequency
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Figure 28-7. Frequency Response up to 128x Sampling Frequency
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28.7 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 28-2. ABDACB Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CR Read/Write 0x00000000
0x04 Sample Data Register 0 SDR0 Read/Write 0x00000000
0x08 Sample Data Register 1 SDR1 Read/Write 0x00000000
0x0C Volume Control Register 0 VCR0 Read/Write 0x00000000
0x10 Volume Control Register 1 VCR1 Read/Write 0x00000000
0x14 Interrupt Enable Register IER Write-only 0x00000000
0x18 Interrupt Disable Register IDR Write-only 0x00000000
0x1C Interrupt Mask Register IMR Read-only 0x00000000
0x20 Status Register SR Read-only 0x00000000
0x24 Status Clear Register SCR Write-only 0x00000000
0x28 Parameter Register PARAMETER Read-only -
(1)
0x2C Version Register VERSION Read-only -
(1)
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28.7.1 Control Register
Name: CR
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• FS: Sampling Frequency
Must be set to the matching data sampling frequency, see Table 28-3.
Note: 1. The actual clock requirement are 11.9952MHz, 23.9904MHz, and 47.9808MHz, but this is
very close to the suggested clock frequencies, and will only result in a very small frequency
shift. This need to be accounted for during testing if comparing to a reference signal.
Notes: 1.
31 30 29 28 27 26 25 24
- - - - FS
23 22 21 20 19 18 17 16
- - - - - DATAFORMAT
15 14 13 12 11 10 9 8
--------
76543210
SWRST - MONO CMOC ALTUPR - SWAP EN
Table 28-3. Generic Clock Requirements
CR.FS Description GCLK (CR.ALTUPR=1) GCLK (CR.ALTUPR=0)
0 8000Hz sampling frequency 8.0MHz 8.1920MHz
1 11025Hz sampling frequency 12.0MHz(1) 11.2896MHz
2 12000Hz sampling frequency 12.0MHz 12.2880MHz
3 16000Hz sampling frequency 16.0MHz 16.3840MHz
4 22050Hz sampling frequency 24.0MHz(1) 22.5792MHz
5 24000Hz sampling frequency 24.0MHz 24.5760MHz
6 32000Hz sampling frequency 32.0MHz 32.7680MHz
7 44100Hz sampling frequency 48.0MHz(1) 45.1584MHz
8 48000Hz sampling frequency 48.0MHz 49.1520MHz
Other Reserved - -
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• DATAFORMAT: Data Word Format
• SWRST: Software Reset
Writing a zero to this bit does not have any effect.
Writing a one to this bit will reset the ABDACB as if a hardware reset was done.
• MONO: Mono Mode
0: Mono mode is disabled.
1: Mono mode is enabled.
• CMOC: Common Mode Offset Control
0: Common mode adjustment is disabled.
1: Common mode adjustment is enabled.
• ALTUPR: Alternative Upsampling Ratio
0: Alternative upsampling is disabled.
1: Alternative upsampling is enabled.
• SWAP: Swap Channels
0: Channel swap is disabled.
1: Channel swap is enabled.
• EN: Enable
0: The ABDACB is disabled.
1: The ABDACB is enabled.
Table 28-4. Data Word Format
DATAFORMAT Word length Comment
0 32 bits
1 24 bits
2 20 bits
3 18 bits
4 16 bits
5 16 bits compact stereo Channel 1 sample in bits 31 through 16, channel 0 sample in bits 15 through 0 in SDR0
6 8 bits
7 8 bits compact stereo Channel 1 sample in bits 15 through 8, channel 0 sample in bits 7through 0 in SDR0
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28.7.2 Sample Data Register 0
Name: SDR0
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• DATA: Sample Data
Sample Data for channel 0 in two’s complement format. Data must be right-justified, see Table 28-5.
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
Table 28-5. Sample Data Register Formats
Data Format SDR0 SDR1 Comment
32 bits CH0 sample in DATA[31:0] CH1 sample in DATA[31:0]
24 bits CH0 sample in DATA[23:0] CH1 sample in DATA[23:0] Remaining bits are ignored.
20 bits CH0 sample in DATA[19:0] CH1 sample in DATA[19:0] Remaining bits are ignored.
18 bits CH0 sample in DATA[17:0] CH1 sample in DATA[17:0] Remaining bits are ignored.
16 bits CH0 sample in DATA[15:0] CH1 sample in DATA[15:0] Remaining bits are ignored.
16 bits compact stereo CH0 sample in DATA[15:0]
CH1 sample in DATA[31:16] Not used
8 bits CH0 sample in DATA[7:0] CH1 sample in DATA[7:0] Remaining bits are ignored.
8 bits compact stereo CH0 sample in DATA[7:0]
CH1 sample in DATA[15:8] Not used Remaining bits are ignored.
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28.7.3 Sample Data Register 1
Name: SDR1
Access Type: Read/Write
Offset: 0x08
Reset Value: 0x00000000
• DATA: Sample Data
Sample Data for channel 1 in two’s complement format. Data must be right-justified, see Table 28-5 on page 699.
31 30 29 28 27 26 25 24
DATA[31:24]
23 22 21 20 19 18 17 16
DATA[23:16]
15 14 13 12 11 10 9 8
DATA[15:8]
76543210
DATA[7:0]
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28.7.4 Volume Control Register 0
Name: VCR0
Access Type: Read/Write
Offset: 0x0C
Reset Value: 0x00000000
• MUTE: Mute
0: Channel 0 is not muted.
1: Channel 0 is muted.
• VOLUME: Volume Control
15-bit value adjusting the volume for channel 0.
31 30 29 28 27 26 25 24
MUTE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- VOLUME[14:8]
76543210
VOLUME[7:0]
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28.7.5 Volume Control Register 1
Name: VCR1
Access Type: Read/Write
Offset: 0x10
Reset Value: 0x00000000
• MUTE: Mute
0: Channel 1 is not muted.
1: Channel 1 is muted.
• VOLUME: Volume Control
15-bit value adjusting the volume for channel 1.
31 30 29 28 27 26 25 24
MUTE - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- VOLUME[14:8]
76543210
VOLUME[7:0]
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28.7.6 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TXUR TXRDY -
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28.7.7 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x18
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TXUR TXRDY -
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28.7.8 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TXUR TXRDY -
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28.7.9 Status Register
Name: SR
Access Type: Read-only
Offset: 0x20
Reset Value: 0x00000000
• TXUR: Transmit Underrun
This bit is cleared when no underrun has occurred since the last time this bit was cleared (by reset or by writing to SCR).
This bit is set when at least one underrun has occurred since the last time this bit was cleared (by reset or by writing to SCR).
• TXRDY: Transmit Ready
This bit is cleared when the ABDACB is not ready to receive a new data in SDR.
This bit is set when the ABDACB is ready to receive a new data in SDR.
• BUSY: ABDACB Busy
This bit is set when the ABDACB is busy doing a data transfer between clock domains. CR, SDR0, and SDR1 can not be written
during this time.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TXUR TXRDY BUSY
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28.7.10 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x24
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TXUR TXRDY -
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28.7.11 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x28
Reset Value: 0x00000000
Reserved. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
--------
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28.7.12 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x2C
Reset Value: 0x00000000
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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28.8 Module Configuration
The specific configuration for each ABDACB instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 28-6. ABDACB Clocks
Clock Name Description
CLK_ABDACB Clock for the ABDACB bus interface
GCLK The generic clock used for the ABDACB is GCLK6
Table 28-7. Register Reset Values
Register Reset Value
VERSION 0x00000100
PARAMETER 0x00000000
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29. ADC Interface (ADCIFB)
Rev:1.0.1.1
29.1 Features
• Multi-channel Analog-to-Digital Converter with up to 12-bit resolution
• Enhanced Resolution Mode
– 11-bit resolution obtained by interpolating 4 samples
– 12-bit resolution obtained by interpolating 16 samples
• Glueless interface with resistive touch screen panel, allowing
– Resistive Touch Screen position measurement
– Pen detection and pen loss detection
• Integrated enhanced sequencer
– ADC Mode
– Resistive Touch Screen Mode
• Numerous trigger sources
– Software
– Embedded 16-bit timer for periodic trigger
– Pen detect trigger
– Continuous trigger
– External trigger, rising, falling, or any-edge trigger
– Peripheral event trigger
• ADC Sleep Mode for low power ADC applications
• Programmable ADC timings
– Programmable ADC clock
– Programmable startup time
29.2 Overview
The ADC Interface (ADCIFB) converts analog input voltages to digital values. The ADCIFB is
based on a Successive Approximation Register (SAR) 10-bit Analog-to-Digital Converter (ADC).
The conversions extend from 0V to ADVREFP.
The ADCIFB supports 8-bit and 10-bit resolution mode, in addition to enhanced resolution mode
with 11-bit and 12-bit resolution. Conversion results are reported in a common register for all
channels.
The 11-bit and 12-bit resolution modes are obtained by interpolating multiple samples to acquire
better accuracy. For 11-bit mode 4 samples are used, which gives an effective sample rate of
1/4 of the actual sample frequency. For 12-bit mode 16 samples are used, giving a effective
sample rate of 1/16 of actual. This arrangement allows conversion speed to be traded for better
accuracy.
Conversions can be started for all enabled channels, either by a software trigger, by detection of
a level change on the external trigger pin (TRIGGER), or by an integrated programmable timer.
When the Resistive Touch Screen Mode is enabled, an integrated sequencer automatically configures
the pad control signals and performs resistive touch screen conversions.
The ADCIFB also integrates an ADC Sleep Mode, a Pen-Detect Mode, and an Analog Compare
Mode, and connects with one Peripheral DMA Controller channel. These features reduce both
power consumption and processor intervention.
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29.3 Block Diagram
Figure 29-1. ADCIFB Block Diagram
ADVREFP
Analog Multiplexer
Successive
Approximation
Register
Analog-to-Digital
Converter
Trigger
ADC Control
Logic
Timer
User
Interface
AD0
AD1
AD3
ADn
AD2
Resisitve Touch
Screen
Sequencer
CLK_ADCIFB
....
ADCIFB
ADP0
ADP1
I/O Controller
TRIGGER
Peripheral
Bus
DMA
Request
Interrupt
Request
CLK_ADC
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29.4 I/O Lines Description
29.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
29.5.1 I/O Lines
The analog input pins can be multiplexed with I/O Controller lines. The user must make sure the
I/O Controller is configured correctly to allow the ADCIFB access to the AD pins before the
ADCIFB is instructed to start converting data. If the user fails to do this the converted data may
be wrong.
The number of analog inputs is device dependent, please refer to the ADCIFB Module Configuration
chapter for the number of available AD inputs on the current device.
The ADVREFP pin must be connected correctly prior to using the ADCIFB. Failing to do so will
result in invalid ADC operation. See the Electrical Characteristics chapter for details.
If the TRIGGER, ADP0, and ADP1 pins are to be used in the application, the user must configure
the I/O Controller to assign the needed pins to the ADCIFB function.
29.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the ADCIFB, the ADCIFB will stop
functioning and resume operation after the system wakes up from sleep mode.
If the Peripheral Event System is configured to send asynchronous peripheral events to the
ADCIFB and the clock used by the ADCIFB is stopped, a local and temporary clock will automatically
be requested so the event can be processed. Refer to Section 29.6.13, Section 29.6.12,
and the Peripheral Event System chapter for details.
Before entering a sleep mode where the clock to the ADCIFB is stopped, make sure the Analogto-Digital
Converter cell is put in an inactive state. Refer to Section 29.6.13 for more information.
29.5.3 Clocks
The clock for the ADCIFB bus interface (CLK_ADCIFB) is generated by the Power Manager.
This clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to
disable the ADCIFB before disabling the clock, to avoid freezing the ADCIFB in an undefined
state.
Table 29-1. I/O Lines Description
Pin Name Description Type
ADVREFP Reference voltage Analog
TRIGGER External trigger Digital
ADP0 Drive Pin 0 for Resistive Touch Screen top channel (Xp) Digital
ADP1 Drive Pin 1 for Resistive Touch Screen right channel (Yp) Digital
AD0-ADn Analog input channels 0 to n Analog
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29.5.4 DMA
The ADCIFB DMA handshake interface is connected to the Peripheral DMA Controller. Using
the ADCIFB DMA functionality requires the Peripheral DMA Controller to be programmed first.
29.5.5 Interrupts
The ADCIFB interrupt request line is connected to the interrupt controller. Using the ADCIFB
interrupt request functionality requires the interrupt controller to be programmed first.
29.5.6 Peripheral Events
The ADCIFB peripheral events are connected via the Peripheral Event System. Refer to the
Peripheral Event System chapter for details
29.5.7 Debug Operation
When an external debugger forces the CPU into debug mode, this module continues normal
operation. If this module is configured in a way that requires it to be periodically serviced by the
CPU through interrupt requests or similar, improper operation or data loss may result during
debugging.
29.6 Functional Description
The ADCIFB embeds a Successive Approximation Register (SAR) Analog-to-Digital Converter
(ADC). The ADC supports 8-bit or 10-bit resolution, which can be extended to 11 or 12 bits by
the Enhanced Resolution Mode.
The conversion is performed on a full range between 0V and the reference voltage pin
ADVREFP. Analog inputs between these voltages converts to digital values (codes) based on a
linear conversion. This linear conversion is described in the expression below where M is the
number of bits used to represent the analog value, Vin is the voltage of the analog value to convert,
Vref is the maximum voltage, and Code is the converted digital value.
29.6.1 Initializing the ADCIFB
The ADC Interface is enabled by writing a one to the Enable bit in the Control Register (CR.EN).
After the ADC Interface is enabled, the ADC timings needs to be configured by writing the correct
values to the RES, PRESCAL, and STARTUP fields in the ADC Configuration Register
(ACR). See Section 29.6.5, and Section 29.6.7 for details. Before the ADCIFB can be used, the
I/O Controller must be configured correctly and the Reference Voltage (ADVREFP) signal must
be connected. Refer to Section 29.5.1 for details.
29.6.2 Basic Operation
To convert analog values to digital values the user must first initialize the ADCIFB as described
in Section 29.6.1. When the ADCIFB is initialized the channels to convert must be enabled by
writing a one the corresponding bits in the Channel Enable Register (CHER). Enabling channel
N instructs the ADCIFB to convert the analog voltage applied to AD pin N at each conversion
sequence. Multiple channels can be enabled resulting in multiple AD pins being converted at
each conversion sequence.
Code
2M Vin
Vref
= -------------------
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To start converting data the user can either manually start a conversion sequence by writing a
one to the START bit in the Control Register (CR.START) or configure an automatic trigger to
initiate the conversions. The automatic trigger can be configured to trig on many different conditions.
Refer to Section 29.8.1 for details.
The result of the conversion is stored in the Last Converted Data Register (LCDR) as they
become available, overwriting the result from the previous conversion. To avoid data loss if more
than one channel is enabled, the user must read the conversion results as they become available
either by using an interrupt handler or by using a Peripheral DMA channel to copy the
results to memory. Failing to do so will result in an Overrun Error condition, indicated by the
OVRE bit in the Status Register (SR).
To use an interrupt handler the user must enable the Data Ready (DRDY) interrupt request by
writing a one to the corresponding bit in the Interrupt Enable Register (IER). To clear the interrupt
after the conversion result is read, the user must write a one to the corresponding bit in the
Interrupt Clear Register (ICR). See Section 29.6.11 for details.
To use a Peripheral DMA Controller channel the user must configure the Peripheral DMA Controller
appropriately. The Peripheral DMA Controller will, when configured, automatically read
converted data as they become available. There is no need to manually clear any bits in the
Interrupt Status Register as this is performed by the hardware. If an Overrun Error condition happens
during DMA operation, the OVRE bit in the SR will be set.
29.6.3 ADC Resolution
The Analog-to-Digital Converter cell supports 8-bit or 10-bit resolution, which can be extended to
11-bit and 12-bit with the Enhanced Resolution Mode. The resolution is selected by writing the
selected resolution value to the RES field in the ADC Configuration Register (ACR). See Section
29.9.3.
By writing a zero to the RES field, the ADC switches to the lowest resolution and the conversion
results can be read in the eight lowest significant bits of the Last Converted Data Register
(LCDR). The four highest bits of the Last Converted Data (LDATA) field in the LCDR register
reads as zero. Writing a one to the RES field enables 10-bit resolution, the optimal resolution for
both sampling speed and accuracy. Writing two or three automatically enables Enhanced Resolution
Mode with 11-bit or 12-bit resolution, see Section 29.6.4 for details.
When a Peripheral DMA Controller channel is connected to the ADCIFB in 10-bit, 11-bit, or 12-
bit resolution mode, a transfer size of 16 bits must be used. By writing a zero to the RES field,
the destination buffers can be optimized for 8-bit transfers.
29.6.4 Enhanced Resolution Mode
The Enhanced Resolution Mode is automatically enabled when 11-bit or 12-bit mode is selected
in the ADC Configuration Register (ACR). In this mode the ADCIFB will trade conversion performance
for accuracy by averaging multiple samples.
To be able to increase the accuracy by averaging multiple samples it is important that some
noise is present in the input signal. The noise level should be between one and two LSB peakto-peak
to get good averaging performance.
The performance cost of enabling 11-bit mode is 4 ADC samples, which reduces the effective
ADC performance by a factor 4. For 12-bit mode this factor is 16. For 12-bit mode the effective
sample rate is maximum ADC sample rate divided by 16.
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29.6.5 ADC Clock
The ADCIFB generates an internal clock named CLK_ADC that is used by the Analog-to-Digital
Converter cell to perform conversions. The CLK_ADC frequency is selected by writing to the
PRESCAL field in the ADC Configuration Register (ACR). The CLK_ADC range is between
CLK_ADCIFB/2, if PRESCAL is 0, and CLK_ADCIFB/128, if PRESCAL is 63 (0x3F).
A sensible PRESCAL value must be used in order to provide an ADC clock frequency according
to the maximum sampling rate parameter given in the Electrical Characteristics section. Failing
to do so may result in incorrect Analog-to-Digital Converter operation.
29.6.6 ADC Sleep Mode
The ADC Sleep Mode maximizes power saving by automatically deactivating the Analog-to-Digital
Converter cell when it is not being used for conversions. The ADC Sleep Mode is enabled by
writing a one to the SLEEP bit in the ADC Configuration Register (ACR).
When a trigger occurs while the ADC Sleep Mode is enabled, the Analog-to-Digital Converter
cell is automatically activated. As the analog cell requires a startup time, the logic waits during
this time and then starts the conversion of the enabled channels. When conversions of all
enabled channels are complete, the ADC is deactivated until the next trigger.
29.6.7 Startup Time
The Analog-to-Digital Converter cell has a minimal startup time when the cell is activated. This
startup time is given in the Electrical Characteristics chapter and must be written to the
STARTUP field in the ADC Configuration Register (ACR) to get correct conversion results.
The STARTUP field expects the startup time to be represented as the number of CLK_ADC
cycles between 8 and 1024 and in steps of 8 that is needed to cover the ADC startup time as
specified in the Electrical Characteristics chapter.
The Analog-to-Digital Converter cell is activated at the first conversion after reset and remains
active if ACR.SLEEP is zero. If ACR.SLEEP is one, the Analog-to-Digital Converter cell is automatically
deactivated when idle and thus each conversion sequence will have a initial startup
time delay.
29.6.8 Sample and Hold Time
A minimal Sample and Hold Time is necessary for the ADCIFB to guarantee the best converted
final value when switching between ADC channels. This time depends on the input impedance
of the analog input, but also on the output impedance of the driver providing the signal to the
analog input, as there is no input buffer amplifier.
The Sample and Hold time has to be programmed through the SHTIM field in the ADC Configuration
Register (ACR). This field can define a Sample and Hold time between 1 and 16
CLK_ADC cycles.
29.6.9 ADC Conversion
ADC conversions are performed on all enabled channels when a trigger condition is detected.
For details regarding trigger conditions see Section 29.8.1. The term channel is used to identify
a specific analog input pin so it can be included or excluded in an Analog-to-Digital conversion
sequence and to identify which AD pin was used to convert the current value in the Last Converted
Data Register (LCDR). Channel number N corresponding to AD pin number N.
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Channels are enabled by writing a one to the corresponding bit in the Channel Enable Register
(CHER), and disabled by writing a one to the corresponding bit in the Channel Disable Register
(CHDR). Active channels are listed in the Channel Status Register (CHSR).
When a conversion sequence is started, all enabled channels will be converted in one sequence
and the result will be placed in the Last Converted Data Register (LCDR) with the channel number
used to produce the result. It is important to read out the results while the conversion
sequence is ongoing, as new values will automatically overwrite any old value and the old value
will be lost if not previously read by the user.
If the Analog-to-Digital Converter cell is inactive when starting a conversion sequence, the conversion
logic will wait a configurable number of CLK_ADC cycles as defined in the startup time
field in the ADC Configuration Register (ACR). After the cell is activated all enabled channels is
converted one by one until no more enabled channels exist. The conversion sequence converts
each enabled channel in order starting with the channel with the lowest channel number. If the
ACR.SLEEP bit is one, the Analog-to-Digital Converter cell is deactivated after the conversion
sequence has finished.
For each channel converted, the ADCIFB waits a Sample and Hold number of CLK_ADC cycles
as defined in the SHTIM field in ACR, and then instructs the Analog-to-Digital Converter cell to
start converting the analog voltage. The ADC cell requires 10 CLK_ADC cycles to actually convert
the value, so the total time to convert a channel is Sample and Hold + 10 CLK_ADC cycles.
29.6.10 Analog Compare Mode
The ADCIFB can test if the converted values, as they become available, are below, above, or
inside a specified range and generate interrupt requests based on this information. This is useful
for applications where the user wants to monitor some external analog signal and only initiate
actions if the value is above, below, or inside some specified range.
The Analog Compare mode is enabled by writing a one to the Analog Compare Enable (ACE) bit
in the Mode Register (MR). The values to compare must be written to the Low Value (LV) field
and the High Value (HV) field in the Compare Value Register (CVR). The Analog Compare
mode will, when enabled, check all enabled channels against the pre-programmed high and low
values and set status bits.
To generate an interrupt request if a converted value is below a limit, write the limit to the
CVR.LV field and enable interrupt request on the Compare Lesser Than (CLT) bit by writing a
one to the corresponding bit in the Interrupt Enable Register (IER). To generate an interrupt
request if a converted value is above a limit, write the limit to the CVR.HV field and enable interrupt
for Compare Greater Than (CGT) bit. To generate an interrupt request if a converted value
is inside a range, write the low and high limit to the LV and HV fields and enable the Compare
Else (CELSE) interrupt. To generate an interrupt request if a value is outside a range, write the
LV and HV fields to the low and high limits of the range and enable CGT and CLT interrupts.
Note that the values written to LV and HV must match the resolution selected in the ADC Configuration
Register (ACR).
29.6.11 Interrupt Operation
Interrupt requests are enabled by writing a one to the corresponding bit in the Interrupt Enable
Register (IER) and disabled by writing a one to the corresponding bit in the Interrupt Disable
Register (IDR). Enabled interrupts can be read from the Interrupt Mask Register (IMR). Active
interrupt requests, but potentially masked, are visible in the Interrupt Status Register (ISR). To
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clear an active interrupt request, write a one to the corresponding bit in the Interrupt Clear Register
(ICR).
The source for the interrupt requests are the status bits in the Status Register (SR). The SR
shows the ADCIFB status at the time the register is read. The Interrupt Status Register (ISR)
shows the status since the last write to the Interrupt Clear Register. The combination of ISR and
SR allows the user to react to status change conditions but also allows the user to read the current
status at any time.
29.6.12 Peripheral Events
The Peripheral Event System can be used together with the ADCIFB to allow any peripheral
event generator to be used as a trigger source. To enable peripheral events to trigger a conversion
sequence the user must write the Peripheral Event Trigger value (0x7) to the Trigger Mode
(TRGMOD) field in the Trigger Register (TRGR). Refer to Table 29-4 on page 730. The user
must also configure a peripheral event generator to emit peripheral events for the ADCIFB to
trigger on. Refer to the Peripheral Event System chapter for details.
29.6.13 Sleep Mode
Before entering sleep modes the user must make sure the ADCIFB is idle and that the Analogto-Digital
Converter cell is inactive. To deactivate the Analog-to-Digital Converter cell the SLEEP
bit in the ADC Configuration Register (ACR) must be written to one and the ADCIFB must be
idle. To make sure the ADCIFB is idle, write a zero the Trigger Mode (TRGMOD) field in the
Trigger Register (TRGR) and wait for the READY bit in the Status Register (SR) to be set.
Note that by deactivating the Analog-to-Digital Converter cell, a startup time penalty as defined
in the STARTUP field in the ADC Configuration Register (ACR) will apply on the next
conversion.
29.6.14 Conversion Performances
For performance and electrical characteristics of the ADCIFB, refer to the Electrical Characteristics
chapter.
29.7 Resistive Touch Screen
The ADCIFB embeds an integrated Resistive Touch Screen Sequencer that can be used to calculate
contact coordinates on a resistive touch screen film. When instructed to start, the
integrated Resistive Touch Screen Sequencer automatically applies a sequence of voltage patterns
to the resistive touch screen films and the Analog-to-Digital Conversion cell is used to
measure the effects. The resulting measurements can be used to calculate the horizontal and
vertical contact coordinates. It is recommended to use a high resistance touch screen for optimal
resolution.
The resistive touch screen film is connected to the ADCIFB using the AD and ADP pins. See
Section 29.7.3 for details.
Resistive Touch Screen Mode is enabled by writing a one to the Touch Screen ADC Mode field
in the Mode Register (MR.TSAMOD). In this mode, channels TSPO+0 though TSPO+3 are
automatically enabled where TSPO refers to the Touch Screen Pin Offset field in the Mode Register
(MR.TSPO). For each conversion sequence, all enabled channels before TSPO+0 and
after TSPO+3 are converted as ordinary ADC channels, producing 1 conversion result each.
When the sequencer enters the TSPO+0 channel the Resistive Touch Screen Sequencer will
take over control and convert the next 4 channels as described in Section 29.7.4.
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29.7.1 Resistive Touch Screen Principles
A resistive touch screen is based on two resistive films, each one fitted with a pair of electrodes,
placed at the top and bottom on one film, and on the right and left on the other. Between the two,
there is a layer that acts as an insulator, but makes a connection when pressure is applied to the
screen. This is illustrated in Figure 29-2 on page 719.
Figure 29-2. Resistive Touch Screen Position Measurement
29.7.2 Position Measurement Method
As shown in Figure 29-2 on page 719, to detect the position of a contact, voltage is first applied
to XP (top) and Xm (bottom) leaving Yp and Ym tristated. Due to the linear resistance of the film,
there is a voltage gradient from top to bottom on the first film. When a contact is performed on
the screen, the voltage at the contact point propagates to the second film. If the input impedance
on the YP (right) and Ym (left) electrodes are high enough, no current will flow, allowing the voltage
at the contact point to be measured at Yp. The value measured represents the vertical
position component of the contact point.
For the horizontal direction, the same method is used, but by applying voltage from YP (right) to
Ym (left) and measuring at XP.
In an ideal world (linear, with no loss), the vertical position is equal to:
VYP / VDD
To compensate for some of the real world imperfections, VXP and VXm can be measured and
used to improve accuracy at the cost of two more conversions per axes. The new expression for
the vertical position then becomes:
(VYP - VXM) / (VXP - VXM)
XM
XP
YM YP
XP
XM
YP
VDD
GND
Volt
Horizontal Position Detection
YP
YM
XP
VDD
GND
Volt
Vertical Position Detection
Pen
Contact
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29.7.3 Resistive Touch Screen Pin Connections
The resistive touch screen film signals connects to the ADCIFB using the AD and ADP pins. The
XP (top) and XM (bottom) film signals are connected to ADtspo+0 and ADtspo+1 pins, and the YP
(right) and YM (left) signals are connected to ADtspo+2 and ADtspo+3 pins. The tspo index is
configurable through the Touch Screen Pin Offset (TSPO) field in the Mode Register (MR) and
allows the user to configure which AD pins to use for resistive touch screen applications. Writing
a zero to the TSPO field instructs the ADCIFB to use AD0 through AD3, where AD0 is connected
to XP, AD1 is connected to XM and so on. Writing a one to the TSPO field instructs the
ADCIFB to use AD1 through AD4 for resistive touch screen sequencing, where AD1 is connected
to XP and AD0 is free to be used as an ordinary ADC channel.
When the Analog Pin Output Enable (APOE) bit in the Mode Register (MR) is zero, the AD pins
are used to measure input voltage and drive the GND sequences, while the ADP pins are used
to drive the VDD sequences. This arrangement allows the user to reduce the voltage seen at the
AD input pins by inserting external resistors between ADP0 and XP and ADP1 and YP signals
which are again directly connected to the AD pins. It is important that the voltages observed at
the AD pins are not higher than the maximum allowed ADC input voltage. See Figure 29-3 on
page 721 for details regarding how to connect the resistive touch screen films to the AD and
ADP pins.
By adding a resistor between ADP0 and XP, and ADP1 and YP, the maximum voltage observed
at the AD pins can be controlled by the following voltage divider expressions:
The Rfilmx parameter is the film resistance observed when measuring between XP and XM. The
Rresistorx parameter is the resistor size inserted between ADP0 and XP. The definition of Rfilmy
and Rresistory is the same but for ADP1, YP, and YM instead.
Table 29-2. Resistive Touch Screen Pin Connections
ADCIFB Pin TS Signal, APOE == 0 TS Signal, APOE == 1
ADP0 Xp through a resistor No Connect
ADP1 Yp through a resistor No Connect
ADtspo+0 Xp Xp
ADtspo+1 Xm Xm
ADtspo+2 Yp Yp
ADtspo+3 Ym Ym
V ADtspo + 0
Rfilmx
Rfilmx Rresistorx + -------------------------------------------- V DP0 =
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The ADP pins are used by default, as the APOE bit is zero after reset. Writing a one to the
APOE bit instructs the ADCIFB Resistive Touch Screen Sequencer to use the already connected
ADtspo+0 and ADtspo+2 pins to drive VDD to XP and YP signals directly. In this mode the
ADP pins can be used as general purpose I/O pins.
Before writing a one to the APOE bit the user must make sure that the I/O voltage is compatible
with the ADC input voltage. If the I/O voltage is higher than the maximum input voltage of the
ADC, permanent damage may occur. Refer to the Electrical Characteristics chapter for details.
Figure 29-3. Resistive Touch Screen Pin Connections
V ADtspo + 2
Rfilmy
Rfilmy Rresistory + -------------------------------------------- V DP1 =
ADtspo+1
XM
XP
YM YP
ADtspo+0
DP1
DP0
ADtspo+3
ADtspo+2
Analog Pin Output Enable (MR.APOE) == 0
ADtspo+1
XM
XP
YM YP
ADtspo+0
DP1
DP0
ADtspo+3
ADtspo+2
Analog Pin Output Enable (MR.APOE) == 1
NC
NC
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29.7.4 Resistive Touch Screen Sequencer
The Resistive Touch Screen Sequencer is responsible for applying voltage to the resistive touch
screen films as described in Section 29.7.2. This is done by controlling the output enable and the
output value of the ADP and AD pins. This allows the Resistive Touch Screen Sequencer to add
a voltage gradient on one film while keeping the other film floating so a touch can be measured.
The Resistive Touch Screen Sequencer will when measuring the vertical position, apply VDD
and GND to the pins connected to XP and XM. The YP and YM pins are put in tristate mode so the
measurement of YP can proceed without interference. To compensate for ADC offset errors and
non ideal pad drivers, the actual voltage of XP and XM is measured as well, so the real values for
VDD and GND can be used in the contact point calculation to increase accuracy. See second
formula in Section 29.7.2.
When the vertical values are converted the same setup is applies for the second axes, by setting
XP and XM in tristate mode and applying VDD and GND to YP and YM. Refer to Section 29.8.3 for
details.
29.7.5 Pen Detect
If no contact is applied to the resistive touch screen films, any resistive touch screen conversion
result will be undefined as the film being measured is floating. This can be avoided by enabling
Pen Detect and only trigger resistive touch screen conversions when the Pen Contact
(PENCNT) status bit in the Status Register (SR) is one. Pen Detect is enabled by writing a one
to the Pen Detect (PENDET) bit in the Mode Register (MR).
When Pen Detect is enabled, the ADCIFB grounds the vertical panel by applying GND to XP and
XM and polarizes the horizontal panel by enabling pull-up on the pin connected to YP. The YM pin
will in this mode be tristated. Since there is no contact, no current is flowing and there is no
related power consumption. As soon as a contact occurs, GND will propagate to YM by pulling
down YP, allowing the contact to be registered by the ADCIFB.
A programmable debouncing filter can be used to filter out false pen detects because of noise.
The debouncing filter is programmable from one CLK_ADC period and up to 215 CLK_ADC periods.
The debouncer length is set by writing to the PENDBC field in MR.
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Figure 29-4. Resistive Touch Screen Pen Detect
The Resistive Touch Screen Pen Detect can be used to generate an ADCIFB interrupt request
or it can be used to trig a conversion, so that a position can be measured as soon as a contact is
detected.
The Pen Detect Mode generates two types of status signals, reported in the Status Register
(SR):
• The bit PENCNT is set when current flows and remains set until current stops.
• The bit NOCNT is set when no current flows and remains set until current flows.
Before a current change is reflected in the SR, the new status must be stable for the duration of
the debouncing time.
Both status conditions can generate an interrupt request if the corresponding bit in the Interrupt
Mask Register (IMR) is one. Refer to Section 29.6.11 on page 717.
XP
XM
YM
YP
Tristate
GND
Pullup T o the ADC
Debouncer Pen Interrupt
PENDBC
GND
Resistive
Touch Screen
Sequencer
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29.8 Operating Modes
The ADCIFB features two operating modes, each defining a separate conversion sequence:
• ADC Mode: At each trigger, all the enabled channels are converted.
• Resistive Touch Screen Mode: At each trigger, all enabled channels plus the resistive touch
screen channels are converted as described in Section 29.8.3. If channels except the
dedicated resistive touch screen channels are enabled, they are converted normally before
and after the resistive touch screen channels are converted.
The operating mode is selected by the TSAMOD field in the Mode Register (MR).
29.8.1 Conversion Triggers
A conversion sequence is started either by a software or by a hardware trigger. When a conversion
sequence is started, all enabled channels will be converted and made available in the
shared Last Converted Register (LCDR).
The software trigger is asserted by writing a one to the START field in the Control Register (CR).
The hardware trigger can be selected by the TRGMOD field in the Trigger Register (TRGR). Different
hardware triggers exist:
• External trigger, either rising or falling or any, detected on the external trigger pin TRIGGER
• Pen detect trigger, depending the PENDET bit in the Mode Register (MR)
• Continuous trigger, meaning the ADCIFB restarts the next sequence as soon as it finishes
the current one
• Periodic trigger, which is defined by the TRGR.TRGPER field
• Peripheral event trigger, allowing the Peripheral Event System to synchronize conversion with
some configured peripheral event source.
Enabling a hardware trigger does not disable the software trigger functionality. Thus, if a hardware
trigger is selected, the start of a conversion can still be initiated by the software trigger.
29.8.2 ADC Mode
In the ADC Mode, the active channels are defined by the Channel Status Register (CHSR). A
channel is enabled by writing a one to the corresponding bit in the Channel Enable Register
(CHER), and disabled by writing a one to the corresponding bit in the Channel Disable Register
(CHDR). The conversion results are stored in the Last Converted Data Register (LCDR) as they
become available, overwriting old conversions.
At each trigger, the following sequence is performed:
1. If ACR.SLEEP is one, wake up the ADC and wait for the startup time.
2. If Channel 0 is enabled, convert Channel 0 and store result in LCDR.
3. If Channel 1 is enabled, convert Channel 1 and store result in LCDR.
4. If Channel N is enabled, convert Channel N and store result in LCDR.
5. If ACR.SLEEP is one, place the ADC cell in a low-power state.
If the Peripheral DMA Controller is enabled, all converted values are transferred continuously
into the memory buffer.
29.8.3 Resistive Touch Screen Mode
Writing a one to the TSAMOD field in the Mode Register (MR) enables Resistive Touch Screen
Mode. In this mode the channels TSPO+0 to TSPO+3, corresponding to the resistive touch
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screen inputs, are automatically activated. In addition, if any other channels are enabled, they
will be converted before and after the resistive touch screen conversion.
At each trigger, the following sequence is performed:
1. If ACR.SLEEP is one, wake up the ADC cell and wait for the startup time.
2. Convert all enabled channels before TSPO and store the results in the LCDR.
3. Apply supply on the inputs XP and XM during the Sample and Hold Time.
4. Convert Channel XM and store the result in TMP.
5. Apply supply on the inputs XP and XM during the Sample and Hold Time.
6. Convert Channel XP, subtract TMP from the result and store the subtracted result in
LCDR.
7. Apply supply on the inputs XP and XM during the Sample and Hold Time.
8. Convert Channel YP, subtract TMP from the result and store the subtracted result in
LCDR.
9. Apply supply on the inputs YP and YM during the Sample and Hold Time.
10. Convert Channel YM and store the result in TMP.
11. Apply supply on the inputs YP and YM during the Sample and Hold Time.
12. Convert Channel YP, subtract TMP from the result and store the subtracted result in
LCDR.
13. Apply supply on the inputs YP and YM during the Sample and Hold Time.
14. Convert Channel XP, subtract TMP from the result and store the subtracted result in
LCDR.
15. Convert all enabled channels after TSPO + 3 and store results in the LCDR.
16. If ACR.SLEEP is one, place the ADC cell in a low-power state.
The resulting buffer structure stored in memory is:
1. XP - XM
2. YP - XM
3. YP - YM
4. XP - YM.
The vertical position can be easily calculated by dividing the data at offset 1(XP - XM) by the data
at offset 2(YP - XM).
The horizontal position can be easily calculated by dividing the data at offset 3(YP - YM) by the
data at offset 4(XP - YM).
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29.9 User Interface
Note: 1. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 29-3. ADCIFB Register Memory Map
Offset Register Name Access Reset
0x00 Control Register CR Write-only -
0x04 Mode Register MR Read/Write 0x00000000
0x08 ADC Configuration Register ACR Read/Write 0x00000000
0x0C Trigger Register TRGR Read/Write 0x00000000
0x10 Compare Value Register CVR Read/Write 0x00000000
0x14 Status Register SR Read-only 0x00000000
0x18 Interrupt Status Register ISR Read-only 0x00000000
0x1C Interrupt Clear Register ICR Write-only -
0x20 Interrupt Enable Register IER Write-only -
0x24 Interrupt Disable Register IDR Write-only -
0x28 Interrupt Mask Register IMR Read-only 0x00000000
0x2C Last Converted Data Register LCDR Read-only 0x00000000
0x30 Parameter Register PARAMETER Read-only -(1)
0x34 Version Register VERSION Read-only -(1)
0x40 Channel Enable Register CHER Write-only -
0x44 Channel Disable Register CHDR Write-only -
0x48 Channel Status Register CHSR Read-only 0x00000000
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29.9.1 Control Register
Register Name: CR
Access Type: Write-only
Offset: 0x00
Reset Value: 0x00000000
• DIS: ADCDIFB Disable
Writing a zero to this bit has no effect.
Writing a one to this bit disables the ADCIFB.
Note: Disabling the ADCIFB effectively stops all clocks in the module so the user must make sure the ADCIFB is idle before
disabling the ADCIFB.
• EN: ADCIFB Enable
Writing a zero to this bit has no effect.
Writing a one to this bit enables the ADCIFB.
Note: The ADCIFB must be enabled before use.
• START: Start Conversion
Writing a zero to this bit has no effect.
Writing a one to this bit starts an Analog-to-Digital conversion.
• SWRST: Software Reset
Writing a zero to this bit has no effect.
Writing a one to this bit resets the ADCIFB, simulating a hardware reset.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - DIS EN
76543210
- - - - - - START SWRST
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29.9.2 Mode Register
Name: MR
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• PENDBC: Pen Detect Debouncing Period
Period = 2PENDBC*TCLK_ADC
• TSPO: Touch Screen Pin Offset
The Touch Screen Pin Offset field is used to indicate which AD pins are connected to the resistive touch screen film edges. Only
an offset is specified and it is assumed that the resistive touch screen films are connected sequentially from the specified offset
pin and up to and including offset + 3 (4 pins).
• APOE: Analog Pin Output Enable
0: AD pins are not used to drive VDD in resistive touch screen sequence.
1: AD pins are used to drive VDD in resistive touch screen sequence.
Note: If the selected I/O voltage configuration is incompatible with the Analog-to-Digital converter cell voltage specification, this
bit must stay cleared to avoid damaging the ADC. In this case the ADP pins must be used to drive VDD instead, as described in
Section 29.7.3. If the I/O and ADC voltages are compatible, the AD pins can be used directly by writing a one to this bit. In this
case the ADP pins can be ignored.
• ACE: Analog Compare Enable
0: The analog compare functionality is disabled.
1: The analog compare functionality is enabled.
• PENDET: Pen Detect
0: The pen detect functionality is disabled.
1: The pen detect functionality is enabled.
Note: Touch detection logic can only be enabled when the ADC sequencer is idle. For successful pen detection the user must
make sure there is enough idle time between consecutive scans for the touch detection logic to settle.
• TSAMOD: Touch Screen ADC Mode
0: Touch Screen Mode is disabled.
1: Touch Screen Mode is enabled.
31 30 29 28 27 26 25 24
PENDBC - - - -
23 22 21 20 19 18 17 16
TSPO
15 14 13 12 11 10 9 8
--------
76543210
- APOE ACE PENDET - - - TSAMOD
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29.9.3 ADC Configuration Register
Name: ACR
Access Type: Read/Write
Offset: 0x08
Reset Value: 0x00000000
• SHTIM: Sample & Hold Time for ADC Channels
• STARTUP: Startup Time
• PRESCAL: Prescaler Rate Selection
• RES: Resolution Selection
0: 8-bit resolution.
1: 10-bit resolution.
2: 11-bit resolution, interpolated.
3: 12-bit resolution, interpolated.
• SLEEP: ADC Sleep Mode
0: ADC Sleep Mode is disabled.
1: ADC Sleep Mode is enabled.
31 30 29 28 27 26 25 24
- - - - SHTIM
23 22 21 20 19 18 17 16
- STARTUP
15 14 13 12 11 10 9 8
- - PRESCAL
76543210
- - RES - - - SLEEP
TSAMPLE&HOLD SHTIM + 2 TCLK_ADC =
TARTUP STARTUP + 1 8 TCLK_AD =
TCLK_ADC = PRESCAL + 1 2 TCLK_ADCIFB
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29.9.4 Trigger Register
Name: TRGR
Access Type: Read/Write
Offset: 0x0C
Reset Value: 0x00000000
• TRGPER: Trigger Period
Effective only if TRGMOD defines a Periodic Trigger.
Defines the periodic trigger period, with the following equations:
Trigger Period = TRGPER *TCLK_ADC
• TRGMOD: Trigger Mode
31 30 29 28 27 26 25 24
TRGPER[15:8]
23 22 21 20 19 18 17 16
TRGPER[7:0]
15 14 13 12 11 10 9 8
--------
76543210
- - - - - TRGMOD
Table 29-4. Trigger Modes
TRGMOD Selected Trigger Mode
0 0 0 No trigger, only software trigger can start conversions
0 0 1 External Trigger Rising Edge
0 1 0 External Trigger Falling Edge
0 1 1 External Trigger Any Edge
100 Pen Detect Trigger (shall be selected only if PENDET is set and TSAMOD = Touch
Screen mode)
1 0 1 Periodic Trigger (TRGPER shall be initiated appropriately)
1 1 0 Continuous Mode
1 1 1 Peripheral Event Trigger
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29.9.5 Compare Value Register
Name: CVR
Access Type: Read/Write
Offset: 0x10
Reset Value: 0x00000000
• HV: High Value
Defines the high value used when comparing analog input.
• LV: Low Value
Defines the low value used when comparing analog input.
31 30 29 28 27 26 25 24
- - - - HV[11:8]
23 22 21 20 19 18 17 16
HV[7:0]
15 14 13 12 11 10 9 8
- - - - LV[11:8]
76543210
LV[7:0]
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29.9.6 Status Register
Name: SR
Access Type: Read-only
Offset: 0x14
Reset Value: 0x00000000
• EN: Enable Status
0: The ADCIFB is disabled.
1: The ADCIFB is enabled.
This bit is cleared when CR.DIS is written to one.
This bit is set when CR.EN is written to one.
• CELSE: Compare Else Status
This bit is cleared when either CLT or CGT are detected or when analog compare is disabled.
This bit is set when no CLT or CGT are detected on the last converted data and analog compare is enabled.
• CGT: Compare Greater Than Status
This bit is cleared when no compare greater than CVR.HV is detected on the last converted data or when analog compare is
disabled.
This bit is set when compare greater than CVR.HV is detected on the last converted data and analog compare is enabled.
• CLT: Compare Lesser Than Status
This bit is cleared when no compare lesser than CVR.LV is detected on the last converted data or when analog compare is
disabled.
This bit is set when compare lesser than CVR.LV is detected on the last converted data and analog compare is enabled.
• BUSY: Busy Status
This bit is cleared when the ADCIFB is ready to perform a conversion sequence.
This bit is set when the ADCIFB is busy performing a convention sequence.
• READY: Ready Status
This bit is cleared when the ADCIFB is busy performing a conversion sequence
This bit is set when the ADCIFB is ready to perform a conversion sequence.
• NOCNT: No Contact Status
This bit is cleared when no contact loss is detected or pen detect is disabled
This bit is set when contact loss is detected and pen detect is enabled.
• PENCNT: Pen Contact Status
This bit is cleared when no contact is detected or pen detect is disabled.
31 30 29 28 27 26 25 24
- - - - - - - EN
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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This bit is set when pen contact is detected and pen detect is enabled.
• OVRE: Overrun Error Status
This bit is cleared when no Overrun Error has occurred since the start of a conversion sequence.
This bit is set when one or more Overrun Error has occurred since the start of a conversion sequence.
• DRDY: Data Ready Status
0: No data has been converted since the last reset.
1: One or more conversions have completed since the last reset and data is available in LCDR.
This bit is cleared when CR.SWRST is written to one.
This bit is set when one or more conversions have completed and data is available in LCDR.
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29.9.7 Interrupt Status Register
Name: ISR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x00000000
• CELSE: Compare Else Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• CGT: Compare Greater Than Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• CLT: Compare Lesser Than Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• BUSY: Busy Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• READY: Ready Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• NOCNT: No Contact Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• PENCNT: Pen Contact Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• OVRE: Overrun Error Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding bit in SR has a zero-to-one transition.
• DRDY: Data Ready Status
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when a conversion has completed and new data is available in LCDR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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29.9.8 Interrupt Clear Register
Name: ICR
Access Type: Write-only
Offset: 0x1C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in ISR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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29.9.9 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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29.9.10 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x24
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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29.9.11 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x28
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared by writing a one to the corresponding bit in Interrupt Disable Register (IDR).
A bit in this register is set by writing a one to the corresponding bit in Interrupt Enable Register (IER).
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- CELSE CGT CLT - - BUSY READY
76543210
- - NOCNT PENCNT - - OVRE DRDY
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29.9.12 Last Converted Data Register
Name: LCDR
Access Type: Read-only
Offset: 0x2C
Reset Value: 0x00000000
• LCCH: Last Converted Channel
This field indicates what channel was last converted, i.e. what channel the LDATA represents.
• LDATA: Last Data Converted
The analog-to-digital conversion data is placed in this register at the end of a conversion on any analog channel and remains
until a new conversion on any analog channel is completed.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
LCCH
15 14 13 12 11 10 9 8
- - - - LDATA[11:8]
76543210
LDATA[7:0]
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29.9.13 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x30
Reset Value: 0x00000000
• CHn: Channel n Implemented
0: The corresponding channel is not implemented.
1: The corresponding channel is implemented.
31 30 29 28 27 26 25 24
CH31 CH30 CH29 CH28 CH27 CH26 CH25 CH24
23 22 21 20 19 18 17 16
CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH16
15 14 13 12 11 10 9 8
CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH8
76543210
CH7 CH6 CH5 CH4 CH3 CH2 CH1 CH0
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29.9.14 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x34
Reset Value: 0x00000000
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the Module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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29.9.15 Channel Enable Register
Name: CHER
Access Type: Write-only
Offset: 0x40
Reset Value: 0x00000000
• CHn: Channel n Enable
Writing a zero to a bit in this register has no effect
Writing a one to a bit in this register enables the corresponding channel
The number of available channels is device dependent. Please refer to the Module Configuration section at the end of this
chapter for information regarding which channels are implemented.
31 30 29 28 27 26 25 24
CH31 CH30 CH29 CH28 CH27 CH26 CH25 CH24
23 22 21 20 19 18 17 16
CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH16
15 14 13 12 11 10 9 8
CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH8
76543210
CH7 CH6 CH5 CH4 CH3 CH2 CH1 CH0
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29.9.16 Channel Disable Register
Name: CHDR
Access Type: Write-only
Offset: 0x44
Reset Value: 0x00000000
• CHn: Channel N Disable
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register disables the corresponding channel.
Warning: If the corresponding channel is disabled during a conversion, or if it is disabled and then re-enabled during a
conversion, its associated data and its corresponding DRDY and OVRE bits in SR are unpredictable.
The number of available channels is device dependent. Please refer to the Module Configuration section at the end of this
chapter for information regarding how many channels are implemented.
31 30 29 28 27 26 25 24
CH31 CH30 CH29 CH28 CH27 CH26 CH25 CH24
23 22 21 20 19 18 17 16
CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH16
15 14 13 12 11 10 9 8
CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH8
76543210
CH7 CH6 CH5 CH4 CH3 CH2 CH1 CH0
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29.9.17 Channel Status Register
Name: CHSR
Access Type: Read-only
Offset: 0x48
Reset Value: 0x00000000
• CHn: Channel N Status
0: The corresponding channel is disabled.
1: The corresponding channel is enabled.
A bit in this register is cleared by writing a one to the corresponding bit in Channel Disable Register (CHDR).
A bit in this register is set by writing a one to the corresponding bit in Channel Enable Register (CHER).
The number of available channels is device dependent. Please refer to the Module Configuration section at the end of this
chapter for information regarding how many channels are implemented.
31 30 29 28 27 26 25 24
CH31 CH30 CH29 CH28 CH27 CH26 CH25 CH24
23 22 21 20 19 18 17 16
CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH16
15 14 13 12 11 10 9 8
CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH8
76543210
CH7 CH6 CH5 CH4 CH3 CH2 CH1 CH0
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29.10 Module Configuration
The specific configuration for each ADCIFB instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Note: 1. AD3 does not exist
Table 29-5. Module Configuration
Feature ADCIFB
Number of ADC channels 9 (8 + 1 internal temperature sensor channel)
Table 29-6. ADCIFB Clocks
Clock Name Description
CLK_ADCIFB Clock for the ADCIFB bus interface
Table 29-7. Register Reset Values
Register Reset Value
VERSION 0x00000110
PARAMETER 0x000003FF
Table 29-8. ADC Input Channels(1)
Channel Input
CH0 AD0
CH1 AD1
CH2 AD2
CH4 AD4
CH5 AD5
CH6 AD6
CH7 AD7
CH8 AD8
CH9 Temperature sensor
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30. Analog Comparator Interface (ACIFB)
Rev: 2.0.2.2
30.1 Features
• Controls an array of Analog Comparators
• Low power option
– Single shot mode support
• Selectable settings for filter option
– Filter length and hysteresis
• Window Mode
– Detect inside/outside window
– Detect above/below window
• Interrupt
– On comparator result rising edge, falling edge, toggle
– Inside window, outside window, toggle
– When startup time has passed
• Can generate events to the peripheral event system
30.2 Overview
The Analog Comparator Interface (ACIFB) is able to control a number of Analog Comparators
(AC) with identical behavior. An Analog Comparator compares two voltages and gives a compare
output depending on this comparison.
The ACIFB can be configured in normal mode using each comparator independently or in window
mode using defined comparator pairs to observe a window.
The number of channels implemented is device specific. Refer to the Module Configuration section
at the end of this chapter for details.
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30.3 Block Diagram
Figure 30-1. ACIFB Block Diagram
30.4 I/O Lines Description
There are two groups of analog comparators, A and B, as shown in Table 30-1. In normal mode,
this grouping does not have any meaning. In window mode, two analog comparators, one from
group A and the corresponding comparator from group B, are paired.
……………...
TRIGGER
EVENTS
IRQ
GCLK
Peripheral Bus ACIFB
Analog
Comparators
PERIPHERAL
EVENT
GENERATION
-
+
AC
INN
INP
CONF0.INSELN
-
+
AC
INN
INP
CONFn.INSELN
FILTER
FILTER
INTERRUPT
GENERATION
CLK_ACIFB
CTRL.ACTEST
TR.ACTESTn
TR.ACTEST0
ACOUT0
ACOUTn
ACP0
ACN0
ACREFN
ACPn
ACNn
Table 30-1. Analog Comparator Groups for Window Mode
Group A Group B Pair Number
AC0 AC1 0
AC2 AC3 1
AC4 AC5 2
AC6 AC7 3
Table 30-2. I/O Line Description
Pin Name Pin Description Type
ACAPn Positive reference pin for Analog Comparator A n Analog
ACANn Negative reference pin for Analog Comparator A n Analog
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The signal names corresponds to the groups A and B of analog comparators. For normal mode,
the mapping from input signal names in the block diagram to the signal names is given in Table
30-3.
30.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
30.5.1 I/O Lines
The ACIFB pins are multiplexed with other peripherals. The user must first program the I/O Controller
to give control of the pins to the ACIFB.
30.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the ACIFB, the ACIFB will stop
functioning and resume operation after the system wakes up from sleep mode.
30.5.3 Clocks
The clock for the ACIFB bus interface (CLK_ACIFB) is generated by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable
the ACIFB before disabling the clock, to avoid freezing the ACIFB in an undefined state.
The ACIFB uses a GCLK as clock source for the Analog Comparators. The user must set up this
GCLK at the right frequency. The CLK_ACIFB clock of the interface must be at least 4x the
GCLK frequency used in the comparators. The GCLK is used both for measuring the startup
time of a comparator, and to give a frequency for the comparisons done in Continuous Measurement
Mode, see Section 30.6.
Refer to the Electrical Characteristics chapter for GCLK frequency limitations.
ACBPn Positive reference pin for Analog Comparator B n Analog
ACBNn Negative reference pin for Analog Comparator B n Analog
ACREFN Reference Voltage for all comparators selectable for INN Analog
Table 30-3. Signal Name Mapping
Pin Name Channel Number Normal Mode
ACAP0/ACAN0 0 ACP0/ACN0
ACBP0/ACBN0 1 ACP1/ACN1
ACAP1/ACAN1 2 ACP2/ACN2
ACBP1/ACBN1 3 ACP3/ACN3
ACAP2/ACAN2 4 ACP4/ACN4
ACBP2/ACBN2 5 ACP5/ACN5
ACAP3/ACAN3 6 ACP6/ACN6
ACBP3/ACBN3 7 ACP7/ACN7
Table 30-2. I/O Line Description
Pin Name Pin Description Type
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30.5.4 Interrupts
The ACIFB interrupt request line is connected to the interrupt controller. Using the ACIFB interrupt
requires the interrupt controller to be programmed first.
30.5.5 Peripheral Events
The ACIFB peripheral events are connected via the Peripheral Event System. Refer to the
Peripheral Event System chapter for details.
30.5.6 Debug Operation
When an external debugger forces the CPU into debug mode, the ACIFB continues normal
operation. If the ACIFB is configured in a way that requires it to be periodically serviced by the
CPU through interrupts or similar, improper operation or data loss may result during debugging.
30.6 Functional Description
The ACIFB is enabled by writing a one to the Control Register Enable bit (CTRL.EN). Additionally,
the comparators must be individually enabled by programming the MODE field in the AC
Configuration Register (CONFn.MODE).
The results from the individual comparators can either be used directly (normal mode), or the
results from two comparators can be grouped to generate a comparison window (window mode).
All comparators need not be in the same mode, some comparators may be in normal mode,
while others are in window mode. There are restrictions on which AC channels that can be
grouped together in a window pair, see Section 30.6.5.
30.6.1 Analog Comparator Operation
Each AC channel can be in one of four different modes, determined by CONFn.MODE:
• Off
• Continuous Measurement Mode (CM)
• User Triggered Single Measurement Mode (UT)
• Event Triggered Single Measurement Mode (ET)
After being enabled, a startup time defined in CTRL.SUT is required before the result of the
comparison is ready. The GCLK is used for measuring the startup time of a comparator,
During the startup time the AC output is not available. When the ACn Ready bit in the Status
Register (SR.ACRDYn) is one, the output of ACn is ready. In window mode the result is available
when both the comparator outputs are ready (SR.ACRDYn=1 and SR.ACRDYn+1=1).
30.6.1.1 Continuous Measurement Mode
In CM, the Analog Comparator is continuously enabled and performing comparisons. This
ensures that the result of the latest comparison is always available in the ACn Current Comparison
Status bit in the Status Register (SR.ACCSn). Comparisons are done on every positive
edge of GCLK.
CM is enabled by writing CONFn.MODE to 1. After the startup time has passed, a comparison is
done and SR is updated. Appropriate peripheral events and interrupts are also generated. New
comparisons are performed continuously until the CONFn.MODE field is written to 0.
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30.6.1.2 User Triggered Single Measurement Mode
In the UT mode, the user starts a single comparison by writing a one to the User Start Single
Comparison bit (CTRL.USTART). This mode is enabled by writing CONFn.MODE to 2. After the
startup time has passed, a single comparison is done and SR is updated. Appropriate peripheral
events and interrupts are also generated. No new comparisons will be performed.
CTRL.USTART is cleared automatically by hardware when the single comparison has been
done.
30.6.1.3 Event Triggered Single Measurement Mode
This mode is enabled by writing CONFn.MODE to 3 and Peripheral Event Trigger Enable
(CTRL.EVENTEN) to one. The ET mode is similar to the UT mode, the difference is that a
peripheral event from another hardware module causes the hardware to automatically set the
Peripheral Event Start Single Comparison bit (CTRL.ESTART). After the startup time has
passed, a single comparison is done and SR is updated. Appropriate peripheral events and
interrupts are also generated. No new comparisons will be performed. CTRL.ESTART is cleared
automatically by hardware when the single comparison has been done.
30.6.1.4 Selecting Comparator Inputs
Each Analog Comparator has one positive (INP) and one negative (INN) input. The positive
input is fed from an external input pin (ACPn). The negative input can either be fed from an
external input pin (ACNn) or from a reference voltage common to all ACs (ACREFN).
The user selects the input source as follows:
• In normal mode with the Negative Input Select and Positive Input Select fields
(CONFn.INSELN and CONFn.INSELP).
• In window mode with CONFn.INSELN, CONFn.INSELP and CONFn+1.INSELN,
CONFn+1,INSELP. The user must configure CONFn.INSELN and CONFn+1.INSELP to the
same source.
30.6.2 Interrupt Generation
The interrupt request will be generated if the corresponding bit in the Interrupt Mask Register
(IMR) is set. Bits in IMR are set by writing a one to the corresponding bit in the Interrupt Enable
Register (IER), and cleared by writing a one to the corresponding bit in the Interrupt Disable
Register (IDR). The interrupt request remains active until the corresponding bit in ISR is cleared
by writing a one to the corresponding bit in the Interrupt Status Clear Register (ICR).
30.6.3 Peripheral Event Generation
The ACIFB can be set up so that certain comparison results notify other parts of the device via
the Peripheral Event system. Refer to Section 30.6.4.3 and Section 30.6.5.3 for information on
which comparison results can generate events, and how to configure the ACIFB to achieve this.
Zero or one event will be generated per comparison.
30.6.4 Normal Mode
In normal mode all Analog Comparators are operating independently.
30.6.4.1 Normal Mode Output
Each Analog Comparator generates one output ACOUT according to the input voltages on INP
(AC positive input) and INN (AC negative input):
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• ACOUT = 1 if VINP > VINN
• ACOUT = 0 if VINP < VINN
• ACOUT = 0 if the AC output is not available (SR.ACRDY = 0)
The output can optionally be filtered, as described in Section 30.6.6.
30.6.4.2 Normal Mode Interrupt
The AC channels can generate interrupts. The Interrupt Settings field in the Configuration Register
(CONFn.IS) can be configured to select when the AC will generate an interrupt:
• When VINP > VINN
• When VINP < VINN
• On toggle of the AC output (ACOUT)
• When comparison has been done
30.6.4.3 Normal Mode Peripheral Events
The ACIFB can generate peripheral events according to the configuration of CONFn.EVENN
and CONFn.EVENP.
• When VINP > VINN or
• When VINP < VINN or
• On toggle of the AC output (ACOUT)
30.6.5 Window Mode
In window mode, two ACs (an even and the following odd build up a pair) are grouped.
The negative input of ACn (even) and the positive input of ACn+1 (odd) has to be connected
together externally to the device and are controlled by the Input Select fields in the AC Configuration
Registers (CONFn.INSELN and CONFn+1.INSELP). The positive input of ACn (even) and
the negative input of ACn+1 (odd) can still be configured independently by CONFn.INSELP and
CONFn+1.INSELN, respectively.
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Figure 30-2. Analog Comparator Interface in Window Mode
30.6.5.1 Window Mode Output
When operating in window mode, each channel generates the same ACOUT outputs as in normal
mode, see Section 30.6.4.1.
Additionally, the ACIFB generates a window mode signal (acwout) according to the common
input voltage to be compared:
• ACWOUT = 1 if the common input voltage is inside the window, VACN(N+1) < Vcommon < VACP(N)
• ACWOUT = 0 if the common input voltage is outside the window, Vcommon < VACN(N+1) or
Vcommon > VACP(N)
• ACWOUT = 0 if the window mode output is not available (SR.ACRDYn=0 or
SR.ACRDYn+1=0)
30.6.5.2 Window Mode Interrupts
When operating in window mode, each channel can generate the same interrupts as in normal
mode, see Section 30.6.4.2.
Additionally, when channels operate in window mode, programming Window Mode Interrupt Settings
in the Window Mode Configuration Register (CONFWn.WIS) can cause interrupts to be
generated when:
• As soon as the common input voltage is inside the window.
• As soon as the common input voltage is outside the window.
• On toggle of the window compare output (ACWOUT).
• When the comparison in both channels in the window pair is ready.
Comparator pair 0
-
+
AC0
Interrupt
Generator
Window
Module
ACOUT0
Peripheral Event
Generator
Window
window event
-
+
AC1
Filter
Filter
SR.ACCS0
SR.WFCS0
ACAP0
ACAN0
ACBP0
COMMON ACWOUT
ACBN0
IRQ
ACOUT1
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30.6.5.3 Window Mode Peripheral Events
When operating in window mode, each channel can generate the same peripheral events as in
normal mode, see Section 30.6.4.3.
Additionally, when channels operate in window mode, programming Window Mode Event Selection
Source (CONFWn.WEVSRC) can cause peripheral events to be generated when:
• As soon as the common input voltage is inside the window.
• As soon as the common input voltage is outside the window.
• On toggle of the window compare output (ACWOUT)
• Whenever a comparison is ready and the common input voltage is inside the window.
• Whenever a comparison is ready and the common input voltage is outside the window.
• When the comparison in both channels in the window pair is ready.
30.6.6 Filtering
The output of the comparator can be filtered to reduce noise. The filter length is determined by
the Filter Length field in the CONFn register (CONFn.FLEN). The filter samples the Analog
Comparator output at the GCLK frequency for 2CONFn.FLEN samples. A separate counter (CNT)
counts the number of cycles the AC output was one. This filter is deactivated if CONFn.FLEN
equals 0.
If the filter is enabled, the Hysteresis Value field HYS in the CONFn register (CONFn.HYS) can
be used to define a hysteresis value. The hysteresis value should be chosen so that:
The filter function is defined by:
The filtering algorithm is explained in Figure 30-3. 2FLEN measurements are sampled. If the number
of measurements that are zero is less than (2FLEN/2 - HYS), the filtered result is zero. If the
number of measurements that are one is more than (2FLEN/2 + HYS), the filtered result is one.
Otherwise, the result is unchanged.
2FLEN
2 ---------------- HYS
CNT 2FLEN
2 ---------------- + HYS comp = 1
2FLEN
2 ---------------- + HYS CNT 2FLEN
2 ----------------–HYS comp unchanged
CNT 2FLEN
2 ----------------–HYS comp = 0
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Figure 30-3. The Filtering Algorithm
30.7 Peripheral Event Triggers
Peripheral events from other modules can trigger comparisons in the ACIFB. All channels that
are set up in Event Triggered Single Measurement Mode will be started simultaneously when a
peripheral event is received. Channels that are operating in Continuous Measurement Mode or
User Triggered Single Measurement Mode will be unaffected by the received event. The software
can still operate these channels independently of channels in Event Triggered Single
Measurement Mode.
A peripheral event will trigger one or more comparisons, in normal or window mode.
30.8 AC Test mode
By writing the Analog Comparator Test Mode (CR.ACTEST) bit to one, the outputs from the ACs
are overridden by the value in the Test Register (TR), see Figure 30-1. This is useful for software
development.
2
FLEN
2
FLEN
2
HYS HYS
”Result=0" ”Result=1"
Result =
UNCHANGED
0
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30.9 User Interface
Note: 1. The reset values for these registers are device specific. Please refer to the Module Configuration section at the end of this
chapter.
Table 30-4. ACIFB Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CTRL Read/Write 0x00000000
0x04 Status Register SR Read-only 0x00000000
0x10 Interrupt Enable Register IER Write-only 0x00000000
0x14 Interrupt Disable Register IDR Write-only 0x00000000
0x18 Interrupt Mask Register IMR Read-only 0x00000000
0x1C Interrupt Status Register ISR Read-only 0x00000000
0x20 Interrupt Status Clear Register ICR Write-only 0x00000000
0x24 Test Register TR Read/Write 0x00000000
0x30 Parameter Register PARAMETER Read-only -(1)
0x34 Version Register VERSION Read-only -(1)
0x80 Window0 Configuration Register CONFW0 Read/Write 0x00000000
0x84 Window1 Configuration Register CONFW1 Read/Write 0x00000000
0x88 Window2 Configuration Register CONFW2 Read/Write 0x00000000
0x8C Window3 Configuration Register CONFW3 Read/Write 0x00000000
0xD0 AC0 Configuration Register CONF0 Read/Write 0x00000000
0xD4 AC1 Configuration Register CONF1 Read/Write 0x00000000
0xD8 AC2 Configuration Register CONF2 Read/Write 0x00000000
0xDC AC3 Configuration Register CONF3 Read/Write 0x00000000
0xE0 AC4 Configuration Register CONF4 Read/Write 0x00000000
0xE4 AC5 Configuration Register CONF5 Read/Write 0x00000000
0xE8 AC6 Configuration Register CONF6 Read/Write 0x00000000
0xEC AC7 Configuration Register CONF7 Read/Write 0x00000000
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30.9.1 Control Register
Name: CTRL
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• SUT: Startup Time
Analog Comparator startup time = .
Each time an AC is enabled, the AC comparison will be enabled after the startup time of the AC.
• ACTEST: Analog Comparator Test Mode
0: The Analog Comparator outputs feeds the channel logic in ACIFB.
1: The Analog Comparator outputs are bypassed with the AC Test Register.
• ESTART: Peripheral Event Start Single Comparison
Writing a zero to this bit has no effect.
Writing a one to this bit starts a comparison and can be used for test purposes.
This bit is cleared when comparison is done.
This bit is set when an enabled peripheral event is received.
• USTART: User Start Single Comparison
Writing a zero to this bit has no effect.
Writing a one to this bit starts a Single Measurement Mode comparison.
This bit is cleared when comparison is done.
• EVENTEN: Peripheral Event Trigger Enable
0: A peripheral event will not trigger a comparison.
1: Enable comparison triggered by a peripheral event.
• EN: ACIFB Enable
0: The ACIFB is disabled.
1: The ACIFB is enabled.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - SUT[9:8]
15 14 13 12 11 10 9 8
SUT[7:0]
76543210
ACTEST - ESTART USTART - - -EVENTEN EN
SUT
FGCLK
----------------
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30.9.2 Status Register
Name: SR
Access Type: Read-only
Offset: 0x04
Reset Value: 0x00000000
• WFCSn: Window Mode Current Status
This bit is cleared when the common input voltage is outside the window.
This bit is set when the common input voltage is inside the window.
• ACRDYn: ACn Ready
This bit is cleared when the AC output (ACOUT) is not ready.
This bit is set when the AC output (ACOUT) is ready, AC is enabled and its startup time is over.
• ACCSn: ACn Current Comparison Status
This bit is cleared when VINP is currently lower than VINN
This bit is set when VINP is currently greater than VINN.
31 30 29 28 27 26 25 24
- - - - WFCS3 WFCS2 WFCS1 WFCS0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
ACRDY7 ACCS7 ACRDY6 ACCS6 ACRDY5 ACCS5 ACRDY4 ACCS4
76543210
ACRDY3 ACCS3 ACRDY2 ACCS2 ACRDY1 ACCS1 ACRDY0 ACCS0
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30.9.3 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x10
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
- - - - WFINT3 WFINT2 WFINT1 WFINT0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SUTINT7 ACINT7 SUTINT6 ACINT6 SUTINT5 ACINT5 SUTINT4 ACINT4
76543210
SUTINT3 ACINT3 SUTINT2 ACINT2 SUTINT1 ACINT1 SUTINT0 ACINT0
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30.9.4 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x14
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
- - - - WFINT3 WFINT2 WFINT1 WFINT0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SUTINT7 ACINT7 SUTINT6 ACINT6 SUTINT5 ACINT5 SUTINT4 ACINT4
76543210
SUTINT3 ACINT3 SUTINT2 ACINT2 SUTINT1 ACINT1 SUTINT0 ACINT0
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30.9.5 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x00000000
• WFINTn: Window Mode Interrupt Mask
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
• SUTINTn: ACn Startup Time Interrupt Mask
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
• ACINTn: ACn Interrupt Mask
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
This bit is cleared when the corresponding bit in IDR is written to one.
This bit is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
- - - - WFINT3 WFINT2 WFINT1 WFINT0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SUTINT7 ACINT7 SUTINT6 ACINT6 SUTINT5 ACINT5 SUTINT4 ACINT4
76543210
SUTINT3 ACINT3 SUTINT2 ACINT2 SUTINT1 ACINT1 SUTINT0 ACINT0
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30.9.6 Interrupt Status Register
Name: ISR
Access Type: Read-only
Offset: 0x1C
Reset Value: 0x00000000
• WFINTn: Window Mode Interrupt Status
0: No Window Mode Interrupt is pending.
1: Window Mode Interrupt is pending.
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding channel pair operating in window mode generated an interrupt.
• SUTINTn: ACn Startup Time Interrupt Status
0: No Startup Time Interrupt is pending.
1: Startup Time Interrupt is pending.
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the startup time of the corresponding AC has passed.
• ACINTn: ACn Interrupt Status
0: No Normal Mode Interrupt is pending.
1: Normal Mode Interrupt is pending.
This bit is cleared when the corresponding bit in ICR is written to one.
This bit is set when the corresponding channel generated an interrupt.
31 30 29 28 27 26 25 24
- - - - WFINT3 WFINT2 WFINT1 WFINT0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SUTINT7 ACINT7 SUTINT6 ACINT6 SUTINT5 ACINT5 SUTINT4 ACINT4
76543210
SUTINT3 ACINT3 SUTINT2 ACINT2 SUTINT1 ACINT1 SUTINT0 ACINT0
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30.9.7 Interrupt Status Clear Register
Name: ICR
Access Type: Write-only
Offset: 0x20
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in ISR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
- - - - WFINT3 WFINT2 WFINT1 WFINT0
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
SUTINT7 ACINT7 SUTINT6 ACINT6 SUTINT5 ACINT5 SUTINT4 ACINT4
76543210
SUTINT3 ACINT3 SUTINT2 ACINT2 SUTINT1 ACINT1 SUTINT0 ACINT0
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30.9.8 Test Register
Name: TR
Access Type: Read/Write
Offset: 0x24
Reset Value: 0x00000000
• ACTESTn: AC Output Override Value
If CTRL.ACTEST is set, the ACn output is overridden with the value of ACTESTn.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
ACTEST7 ACTEST6 ACTEST5 ACTEST4 ACTEST3 ACTEST2 ACTEST1 ACTEST0
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30.9.9 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x30
Reset Value: -
• WIMPLn: Window Pair n Implemented
0: Window Pair not implemented.
1: Window Pair implemented.
• ACIMPLn: Analog Comparator n Implemented
0: Analog Comparator not implemented.
1: Analog Comparator implemented.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - WIMPL3 WIMPL2 WIMPL1 WIMPL0
15 14 13 12 11 10 9 8
--------
76543210
ACIMPL7 ACIMPL6 ACIMPL5 ACIMPL4 ACIMPL3 ACIMPL2 ACIMPL1 ACIMPL0
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30.9.10 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x34
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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30.9.11 Window Configuration Register
Name: CONFWn
Access Type: Read/Write
Offset: 0x80,0x84,0x88,0x8C
Reset Value: 0x00000000
• WFEN: Window Mode Enable
0: The window mode is disabled.
1: The window mode is enabled.
• WEVEN: Window Event Enable
0: Event from awout is disabled.
1: Event from awout is enabled.
• WEVSRC: Event Source Selection for Window Mode
000: Event on acwout rising edge.
001: Event on acwout falling edge.
010: Event on awout rising or falling edge.
011: Inside window.
100: Outside window.
101: Measure done.
110-111: Reserved.
• WIS: Window Mode Interrupt Settings
00: Window interrupt as soon as the input voltage is inside the window.
01: Window interrupt as soon as the input voltage is outside the window.
10: Window interrupt on toggle of window compare output.
11: Window interrupt when evaluation of input voltage is done.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - - - - WFEN
15 14 13 12 11 10 9 8
- - - - WEVEN WEVSRC
7654321 0
- - - - - - WIS
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30.9.12 AC Configuration Register
Name: CONFn
Access Type: Read/Write
Offset: 0xD0,0xD4,0xD8,0xDC,0xE0,0xE4,0xE8,0xEC
Reset Value: 0x00000000
• FLEN: Filter Length
000: Filter off.
n: Number of samples to be averaged =2n
.
• HYS: Hysteresis Value
0000: No hysteresis.
1111: Max hysteresis.
• EVENN: Event Enable Negative
0: Do not output event when ACOUT is zero.
1: Output event when ACOUT is zero.
• EVENP: Event Enable Positive
0: Do not output event when ACOUT is one.
1: Output event when ACOUT is one.
• INSELP: Positive Input Select
00: ACPn pin selected.
01: Reserved.
10: Reserved.
11: Reserved.
• INSELN: Negative Input Select
00: ACNn pin selected.
01: ACREFN pin selected.
10: Reserved.
11: Reserved.
• MODE: Mode
00: Off.
01: Continuous Measurement Mode.
10: User Triggered Single Measurement Mode.
11: Event Triggered Single Measurement Mode.
31 30 29 28 27 26 25 24
- FLEN HYS
23 22 21 20 19 18 17 16
- - - - - - EVENP EVENN
15 14 13 12 11 10 9 8
- - - - INSELP INSELN
7654321 0
- - MODE - - IS
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• IS: Interrupt Settings
00: Comparator interrupt when as VINP > VINN.
01: Comparator interrupt when as VINP < VINN.
10: Comparator interrupt on toggle of Analog Comparator output.
11: Comparator interrupt when comparison of VINP and VINN is done.
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30.10 Module Configuration
The specific configuration for each ACIFB instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Refer to the Power Manager
chapter for details.
Table 30-5. ACIFB Configuration
Feature ACIFB
Number of channels 8
Table 30-6. ACIFB Clocks
Clock Name Description
CLK_ACIFB Clock for the ACIFB bus interface
GCLK The generic clock used for the ACIFB is GCLK4
Table 30-7. Register Reset Values
Register Reset Value
VERSION 0x00000202
PARAMETER 0x000F00FF
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31. Capacitive Touch Module (CAT)
Rev: 4.0.0.0
31.1 Features
• QTouch® method allows N touch sensors to be implemented using 2N physical pins
• QMatrix method allows X by Y matrix of sensors to be implemented using (X+2Y) physical pins
• One autonomous QTouch sensor operates without DMA or CPU intervention
• All QTouch sensors can operate in DMA-driven mode without CPU intervention
• External synchronization to reduce 50 or 60 Hz mains interference
• Spread spectrum sensor drive capability
31.2 Overview
The Capacitive Touch Module (CAT) senses touch on external capacitive touch sensors. Capacitive
touch sensors use no external mechanical components, and therefore demand less
maintenance in the user application.
The module implements the QTouch method of capturing signals from capacitive touch sensors.
The QTouch method is generally suitable for small numbers of sensors since it requires 2 physical
pins per sensor. The module also implements the QMatrix method, which is more
appropriate for large numbers of sensors since it allows an X by Y matrix of sensors to be implemented
using only (X+2Y) physical pins. The module allows methods to function together, so N
touch sensors and an X by Y matrix of sensors can be implemented using (2N+X+2Y) physical
pins.
In addition, the module allows sensors using the QTouch method to be divided into two groups.
Each QTouch group can be configured with different properties. This eases the implementation
of multiple kinds of controls such as push buttons, wheels, and sliders.
All of the QTouch sensors can operate in a DMA-driven mode, known as DMATouch, that allows
detection of touch without CPU intervention. The module also implements one autonomous
QTouch sensor that is capable of detecting touch without DMA or CPU intervention. This allows
proximity or activation detection in low-power sleep modes.
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31.3 Block Diagram
Figure 31-1. CAT Block Diagram
31.4 I/O Lines Description
Interface
Registers Peripheral Bus
Finite State
Machine Capacitor
Charge and
Discharge
Sequence
Generator
Counters
CSAn
SMP
I/O
Controller Pins
Discharge
Current
Sources
DIS
Yn
Analog
Comparators
Peripheral
Event System
CLK_CAT
Analog
Comparator
Interface
SYNC
Capacitive Touch Module (CAT)
CSBn
GCLK_CAT VDIVEN
NOTE:
Italicized
signals and
blocks are
used only for
QMatrix
operation
Table 31-1. I/O Lines Description
Name Description Type
CSAn Capacitive sense A line n I/O
CSBn Capacitive sense B line n I/O
DIS Discharge current control (only used for QMatrix) Analog
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31.5 Product Dependencies
In order to use the CAT module, other parts of the system must be configured correctly, as
described below.
31.5.1 I/O Lines
The CAT pins may be multiplexed with other peripherals. The user must first program the I/O
Controller to give control of the pins to the CAT module. In QMatrix mode, the Y lines must be
driven by the CAT and analog comparators sense the voltage on the Y lines. Thus, the CAT (not
the Analog Comparator Interface) must be the selected function for the Y lines in the I/O
Controller.
By writing ones and zeros to bits in the Pin Mode Registers (PINMODEx), most of the CAT pins
can be individually selected to implement the QTouch method or the QMatrix method. Each pin
has a different name and function depending on whether it is implementing the QTouch method
or the QMatrix method. The following table shows the pin names for each method and the bits in
the PINMODEx registers which control the selection of the QTouch or QMatrix method.
SMP SMP line (only used for QMatrix) Output
SYNC Synchronize signal Input
VDIVEN Voltage divider enable (only used for QMatrix) Output
Table 31-1. I/O Lines Description
Name Description Type
Table 31-2. Pin Selection Guide
CAT Module Pin
Name
QTouch Method
Pin Name
QMatrix Method Pin
Name
Selection Bit in
PINMODEx Register
CSA0 SNS0 X0 SP0
CSB0 SNSK0 X1 SP0
CSA1 SNS1 Y0 SP1
CSB1 SNSK1 YK0 SP1
CSA2 SNS2 X2 SP2
CSB2 SNSK2 X3 SP2
CSA3 SNS3 Y1 SP3
CSB3 SNSK3 YK1 SP3
CSA4 SNS4 X4 SP4
CSB4 SNSK4 X5 SP4
CSA5 SNS5 Y2 SP5
CSB5 SNSK5 YK2 SP5
CSA6 SNS6 X6 SP6
CSB6 SNSK6 X7 SP6
CSA7 SNS7 Y3 SP7
CSB7 SNSK7 YK3 SP7
CSA8 SNS8 X8 SP8
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31.5.2 Clocks
The clock for the CAT module, CLK_CAT, is generated by the Power Manager (PM). This clock
is turned on by default, and can be enabled and disabled in the PM. The user must ensure that
CLK_CAT is enabled before using the CAT module.
QMatrix operations also require the CAT generic clock, GCLK_CAT. This generic clock is generated
by the System Control Interface (SCIF), and is shared between the CAT and the Analog
Comparator Interface. The user must ensure that the GCLK_CAT is enabled in the SCIF before
using QMatrix functionality in the CAT module. For proper QMatrix operation, the frequency of
GCLK_CAT must be less than half the frequency of CLK_CAT. If only QTouch functionality is
used, then GCLK_CAT is unnecessary.
31.5.3 Interrupts
The CAT interrupt request line is connected to the interrupt controller. Using CAT interrupts
requires the interrupt controller to be programmed first.
31.5.4 Peripheral Events
The CAT peripheral events are connected via the Peripheral Event System. Refer to the Peripheral
Event System chapter for details.
31.5.5 Peripheral Direct Memory Access
The CAT module provides handshake capability for a Peripheral DMA Controller. One handshake
controls transfers from the Acquired Count Register (ACOUNT) to memory. A second
handshake requests burst lengths for each (X,Y) pair to the Matrix Burst Length Register
CSB8 SNSK8 X9 SP8
CSA9 SNS9 Y4 SP9
CSB9 SNSK9 YK4 SP9
CSA10 SNS10 X10 SP10
CSB10 SNSK10 X11 SP10
CSA11 SNS11 Y5 SP11
CSB11 SNSK11 YK5 SP11
CSA12 SNS12 X12 SP12
CSB12 SNSK12 X13 SP12
CSA13 SNS13 Y6 SP13
CSB13 SNSK13 YK6 SP13
CSA14 SNS14 X14 SP14
CSB14 SNSK14 X15 SP14
CSA15 SNS15 Y7 SP15
CSB15 SNSK15 YK7 SP15
CSA16 SNS16 X16 SP16
CSB16 SNSK16 X17 SP16
Table 31-2. Pin Selection Guide
CAT Module Pin
Name
QTouch Method
Pin Name
QMatrix Method Pin
Name
Selection Bit in
PINMODEx Register
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(MBLEN) when using the QMatrix acquisition method. Two additional handshakes support DMATouch
by regulating transfers from memory to the DMATouch State Write Register (DMATSW)
and from the DMATouch State Read Register (DMATSR) to memory. The Peripheral DMA Controller
must be configured properly and enabled in order to perform direct memory access
transfers to/from the CAT module.
31.5.6 Analog Comparators
When the CAT module is performing QMatrix acquisition, it requires that on-chip analog comparators
be used as part of the process. These analog comparators are not controlled directly by
the CAT module, but by a separate Analog Comparator (AC) Interface. This interface must be
configured properly and enabled before the CAT module is used. This includes configuring the
generic clock input for the analog comparators to the proper sampling frequency.
The CAT will automatically use the negative peripheral events from the AC Interface on every Y
pin in QMatrix mode. When QMatrix acquisition is used the analog comparator corresponding to
the selected Y pins must be enabled and converting continuously, using the Y pin as the positive
reference and the ACREFN as negative reference.
31.5.7 Debug Operation
When an external debugger forces the CPU into debug mode, the CAT continues normal operation.
If the CAT is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
31.6 Functional Description
31.6.1 Acquisition Types
The CAT module can perform several types of QTouch acquisition from capacitive touch sensors:
autonomous QTouch (one sensor only), DMATouch, QTouch group A, and QTouch group
B. The CAT module can also perform QMatrix acquisition. Each type of acquisition has an associated
set of pin selection and configuration registers that allow a large degree of flexibility.
The following schematic diagrams show typical hardware connections for QTouch and QMatrix
sensors, respectively:
Figure 31-2. CAT Touch Connections
AVR32 Chip
QTouch
Sensor
Cs (Sense Capacitor)
SNSKn
SNSn
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Figure 31-3. CAT Matrix Connections
In order to use the autonomous QTouch detection capability, the user must first set up the
Autonomous Touch Pin Select Register (ATPINS) and Autonomous/DMA Touch Configuration
Registers (ATCFG0 through 3) with appropriate values. The module can then be enabled using
the Control Register (CTRL). After the module is enabled, the module will acquire data from the
autonomous QTouch sensor and use it to determine whether the sensor is activated. The
active/inactive status of the autonomous QTouch sensor is reported in the Status Register (SR),
and it is also possible to configure the CAT to generate an interrupt whenever the status
changes. The module will continue acquiring autonomous QTouch sensor data and updating
autonomous QTouch status until the module is disabled or reset.
In order to use the DMATouch capability, it is first necessary to set up the pin mode registers
(PINMODE0, PINMODE1, and PINMODE2) so that the desired pins are specified as DMATouch.
The Autonomous/DMA Touch Configuration Registers (ATCFG0 through 3) must also be
configured with appropriate values. One channel of the Peripheral DMA Controller must be set
up to transfer state words from a block of memory to the DMATSW register, and another channel
must be set up to transfer state words from the DMATSR register back to the same block of
memory. The module can then be enabled using the CTRL register. After the module is enabled,
the module will acquire count values from each DMATouch sensor. Once the module has
acquired a count value for a sensor, it will use a handshake interface to signal the Peripheral
DMA controller to transfer a state word to the DMATSW register. The module will use the count
value to update the state word, and then the updated state word will be transferred to the
DMATSR register. Another handshake interface will signal the Peripheral DMA controller to
transfer the contents of the DMATSR register back to memory. The status of the DMATouch
sensors can be determined at any time by reading the DMATouch Sensor Status Register
(DMATSS).
AVR32 Chip
Cs0 (Sense Capacitor)
X3
YK0
X6 QMatrix Sensor Array
X7
X2
Y0
YK1
Y1 Cs1 (Sense Capacitor)
SMP
Rsmp1 Rsmp0
VDIVEN
DIS
Rdis
ACREFN
Ra
Rb
NOTE: If the CAT internal
current sources will be enabled,
the SMP signal and Rsmp
resistors should NOT be included
in the design. If the CAT internal
current sources will NOT be
enabled, the DIS signal and Rdis
resistor should NOT be included
in the design.
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In order to use the QMatrix, QTouch group A, or QTouch group B acquisition capabilities, it is
first necessary to set up the pin mode registers (PINMODE0, PINMODE1, and PINMODE2) and
configuration registers (MGCFG0, MGCFG1, TGACFG0, TGACFG1, TGBCFG0, and
TGBCFG1). The module must then be enabled using the CTRL register. In order to initiate
acquisition, it is necessary to perform a write to the Acquisition Initiation and Selection Register
(AISR). The specific value written to AISR determines which type of acquisition will be performed:
QMatrix, QTouch group A, or QTouch group B. The CPU can initiate acquisition by
writing to the AISR.
While QMatrix, QTouch group A, or QTouch group B acquisition is in progress, the module collects
count values from the sensors and buffers them. Availability of acquired count data is
indicated by the Acquisition Ready (ACREADY) bit in the Status Register (SR). The CPU or the
Peripheral DMA Controller can then read the acquired counts from the ACOUNT register.
Because the CAT module is configured with Peripheral DMA Controller capability that can transfer
data from memory to MBLEN and from ACOUNT to memory, the Peripheral DMA Controller
can perform long acquisition sequences and store results in memory without CPU intervention.
31.6.2 Prescaler and Charge Length
Each QTouch acquisition type (autonomous QTouch, QTouch group A, and QTouch group B)
has its own prescaler. Each QTouch prescaler divides down the CLK_CAT clock to an appropriate
sampling frequency for its particular acquisition type. Typical frequencies are 1MHz for
QTouch acquisition and 4MHz for QMatrix burst timing control.
Each QTouch prescaler is controlled by the DIV field in the appropriate Configuration Register 0
(ATCFG0, TGACFG0, or TGBCFG0). The QMatrix burst timing prescaler is controlled by the
DIV field in MGCFG0. Each prescaler uses the following formula to generate the sampling clock:
Sampling clock = CLK_CAT / (2(DIV+1))
The capacitive sensor charge length, discharge length, and settle length can be determined for
each acquisition type using the CHLEN, DILEN, and SELEN fields in Configuration Registers 0
and 1. The lengths are specified in terms of prescaler clocks. In addition, the QMatrix Cx discharge
length can be determined using the CXDILEN field in MGCFG2.
For QMatrix acquisition, the duration of CHLEN should not be set to the same value as the
period of any periodic signal on any other pin. If the duration of CHLEN is the same as the
period of a signal on another pin, it is likely that the other signal will significantly affect measurements
due to stray capacitive coupling. For example, if a 1 MHz signal is generated on another
pin of the chip, then CHLEN should not be 1 microsecond.
For the QMatrix method, burst and capture lengths are set for each (X,Y) pair by writing the
desired length values to the MBLEN register. The write must be done before each X line can
start its acquisition and is indicated by the status bit MBLREQ in the Status Register (SR). A
DMA handshake interface is also connected to this status bit to reduce CPU overhead during
QMatrix acquisitions.
Four burst lengths (BURST0..3) can be written at one time into the MBLEN register. If the current
configuration uses Y lines larger than Y3 the register has to be written a second time. The
first write to MBLEN specifies the burst length for Y lines 0 to 3 in the BURST0 to BURST3 fields,
respectively. The second write specifies the burst length for Y lines 4 to 7 in fields BURST0 to
BURST3, respectively, and so on.
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The Y and YK pins remain clamped to ground apart from the specified number of burst pulses,
when charge is transferred and captured into the sampling capacitor.
31.6.3 Capacitive Count Acquisition
For the QMatrix, QTouch group A, and QTouch group B types of acquisition, the module
acquires count values from the sensors, buffers them, and makes them available for reading in
the ACOUNT register. Further processing of the count values must be performed by the CPU.
When the module performs QMatrix acquisition using multiple Y lines, it starts the capture for
each Y line at the appropriate time in the burst sequence so that all captures finish simultaneously.
For example, suppose that an acquisition is performed on Y0 and Y1 with BURST0=53
and BURST1=60. The module will first toggle the X line 7 times while capturing on Y1 while Y0
and YK0 are clamped to ground. The module will then toggle the X line 53 times while capturing
on both Y1 and Y0.
31.6.4 Autonomous QTouch and DMATouch
For autonomous QTouch and DMATouch, a complete detection algorithm is implemented within
the CAT module. The additional parameters needed to control the detection algorithm must be
specified by the user in the ATCFG2 and ATCFG3 registers.
Autonomous QTouch and DMATouch sensitivity and out-of-touch sensitivity can be adjusted
with the SENSE and OUTSENS fields, respectively, in ATCFG2. Each field accepts values from
one to 255 where 255 is the least sensitive setting. The value in the OUTSENS field should be
smaller than the value in the SENSE field.
To avoid false positives a detect integration filtering technique can be used. The number of successive
detects required is specified in the FILTER field of the ATCFG2 register.
To compensate for changes in capacitance the CAT can recalibrate the autonomous QTouch
sensor periodically. The timing of this calibration is done with the NDRIFT and PDRIFT fields in
the Configuration register, ATCFG3. It is recommended that the PDRIFT value is smaller than
the NDRIFT value.
The autonomous QTouch sensor and DMATouch sensors will also recalibrate if the count value
goes too far positive beyond a threshold. This positive recalibration threshold is specified by the
PTHR field in the ATCFG3 register.
The following block diagram shows the sequence of acquisition and processing operations used
by the CAT module. The AISR written bit is internal and not visible in the user interface.
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Figure 31-4. CAT Acquisition and Processing Sequence
31.6.5 Spread Spectrum Sensor Drive
To reduce electromagnetic compatibility issues, the capacitive sensors can be driven with a
spread spectrum signal. To enable spread spectrum drive for a specific acquisition type, the
user must write a one to the SPREAD bit in the appropriate Configuration Register 1 (MGCFG1,
ATCFG1, TGACFG1, or TGBCFG1).
During spread spectrum operation, the length of each pulse within a burst is varied in a deterministic
pattern, so that the exact same burst pattern is used for a specific burst length. The
maximum spread is determined by the MAXDEV field in the Spread Spectrum Configuration
Register (SSCFG) register. The prescaler divisor is varied in a sawtooth pattern from
(2(DIV+1))-MAXDEV to (2(DIV+1))+MAXDEV and then back to (2(DIV+1))-MAXDEV. For example,
if DIV is 2 and MAXDEV is 3, the prescaler divisor will have the following sequence: 6, 7, 8,
Idle
Acquire
autonomous
touch count
Acquire counts
Update
autonomous
touch detection
algorithm
Wait for all
acquired counts
to be transferred
AISR written flag set?
No Yes
Clear AISR
written flag
No Yes
Autonomous touch
enabled (ATEN)?
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9, 3, 4, 5, 6, 7, 8, 9, 3, 4, etc. MAXDEV must not exceed the value of (2(DIV+1)), or undefined
behavior will occur.
31.6.6 Synchronization
To prevent interference from the 50 or 60 Hz mains line the CAT can trigger acquisition on the
SYNC signal. The SYNC signal should be derived from the mains line. The acquisition will trigger
on a falling edge of this signal. To enable synchronization for a specific acquisition type, the
user must write a one to the SYNC bit in the appropriate Configuration Register 1 (MGCFG1,
ATCFG1, TGACFG1, or TGBCFG1).
For QMatrix acquisition, all X lines must be sampled at a specific phase of the noise signal for
the synchronization to be effective. This can be accomplished by the synchronization timer,
which is enabled by writing a non-zero value to the SYNCTIM field in the MGCFG2 register. This
ensures that the start of the acquisition of each X line is spaced at regular intervals, defined by
the SYNCTIM field.
31.6.7 Resistive Drive
By default, the CAT pins are driven with normal I/O drive properties. Some of the CSA and CSB
pins can optionally drive with a 1k output resistance for improved EMC. The pins that have this
capability are listed in the Module Configuration section.
31.6.8 Discharge Current Sources
The device integrates discharge current sources, which can be used to discharge the sampling
capacitors during the QMatrix measurement phase. The discharge current sources are enabled
by writing the GLEN bit in the Discharge Current Source (DICS) register to one. This enables an
internal reference voltage, which can be either the internal 1.1V band gap voltage or VDDIO/3,
as selected by the INTVREFSEL bit in the DICS register. If the DICS.INTREFSEL bit is one, the
reference voltage is applied across an internal resistor, Rint. Otherwise, the voltage is applied to
the DIS pin, and an external reference resistor must be connected between DIS and ground.
The nominal discharge current is given by the following formula, where Vref is the reference voltage,
Rref is the value of the reference resistor, trim is the value written to the DICS.TRIM field,
and k is a constant of proportionality:
I = (Vref/Rref)*(1+(k*trim))
The values for the internal reference resistor, Rint, and the constant, k, may be found in the Electrical
Characteristics section. The nominal discharge current may be programmed between 2
and 20 µA. The reference current can be fine-tuned by adjusting the trim value in the DICS.TRIM
field.
The reference current is mirrored to each Y-pin if the corresponding bit is written to one in the
DICS.SOURCES field.
31.6.9 Voltage Divider Enable (VDIVEN) Capability
In many QMatrix applications, the sense capacitors will be charged to 50 mV or more and the
negative reference pin (ACREFN) of the analog comparators can be tied directly to ground. In
that case, the relatively small input offset voltage of the comparators will not cause acquisition
problems. However, in certain specialized QMatrix applications such as interpolated touch
screens, it may be desirable for the sense capacitors to be charged to less than 25 mV. When
such small voltages are used on the sense capacitors, the input offset voltage of the comparators
becomes an issue and can cause QMatrix acquisition problems.
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Problems with QMatrix acquisition of small sense capacitor voltages can be solved by connecting
the negative reference pin (ACREFN) to a voltage divider that produces a small positive
voltage (20 mV, typically) to cancel any negative input offset voltage. With a 3.3V supply, recommended
values for the voltage divider are Ra (resistor from positive supply to ACREFN) of 8200
ohm and Rb (resistor from ACREFN to ground) of 50 ohm. These recommended values will produce
20 mV on the ACREFN pin, which should generally be enough to compensate for the
worst-case negative input offset of the analog comparators.
Unfortunately, such a voltage divider constantly draws a small current from the power supply,
reducing battery life in portable applications. In order to prevent this constant power drain, the
CAT module provides a voltage divider enable pin (VDIVEN) that can be used for driving the
voltage divider. The VDIVEN pin provides power to the voltage divider only when the comparators
are actually performing QMatrix comparisons. When the comparators are inactive, the
VDIVEN output is zero. This minimizes the power consumed by the voltage divider.
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31.7 User Interface
Table 31-3. CAT Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CTRL Read/Write 0x00000000
0x04 Autonomous Touch Pin Selection Register ATPINS Read/Write 0x00000000
0x08 Pin Mode Register 0 PINMODE0 Read/Write 0x00000000
0x0C Pin Mode Register 1 PINMODE1 Read/Write 0x00000000
0x10 Autonomous/DMA Touch Configuration Register 0 ATCFG0 Read/Write 0x00000000
0x14 Autonomous/DMA Touch Configuration Register 1 ATCFG1 Read/Write 0x00000000
0x18 Autonomous/DMA Touch Configuration Register 2 ATCFG2 Read/Write 0x00000000
0x1C Autonomous/DMA Touch Configuration Register 3 ATCFG3 Read/Write 0x00000000
0x20 Touch Group A Configuration Register 0 TGACFG0 Read/Write 0x00000000
0x24 Touch Group A Configuration Register 1 TGACFG1 Read/Write 0x00000000
0x28 Touch Group B Configuration Register 0 TGBCFG0 Read/Write 0x00000000
0x2C Touch Group B Configuration Register 1 TGBCFG1 Read/Write 0x00000000
0x30 Matrix Group Configuration Register 0 MGCFG0 Read/Write 0x00000000
0x34 Matrix Group Configuration Register 1 MGCFG1 Read/Write 0x00000000
0x38 Matrix Group Configuration Register 2 MGCFG2 Read/Write 0x00000000
0x3C Status Register SR Read-only 0x00000000
0x40 Status Clear Register SCR Write-only -
0x44 Interrupt Enable Register IER Write-only -
0x48 Interrupt Disable Register IDR Write-only -
0x4C Interrupt Mask Register IMR Read-only 0x00000000
0x50 Acquisition Initiation and Selection Register AISR Read/Write 0x00000000
0x54 Acquired Count Register ACOUNT Read-only 0x00000000
0x58 Matrix Burst Length Register MBLEN Write-only -
0x5C Discharge Current Source Register DICS Read/Write 0x00000000
0x60 Spread Spectrum Configuration Register SSCFG Read/Write 0x00000000
0x64 CSA Resistor Control Register CSARES Read/Write 0x00000000
0x68 CSB Resistor Control Register CSBRES Read/Write 0x00000000
0x6C Autonomous Touch Base Count Register ATBASE Read-only 0x00000000
0x70 Autonomous Touch Current Count Register ATCURR Read-only 0x00000000
0x74 Pin Mode Register 2 PINMODE2 Read/Write 0x00000000
0x78 DMATouch State Write Register DMATSW Write-only 0x00000000
0x7C DMATouch State Read Register DMATSR Read-only 0x00000000
0x80 Analog Comparator Shift Offset Register 0 ACSHI0 Read/Write 0x00000000
0x84 Analog Comparator Shift Offset Register 1 ACSHI1 Read/Write 0x00000000
0x88 Analog Comparator Shift Offset Register 2 ACSHI2 Read/Write 0x00000000
782
32142D–06/2013
ATUC64/128/256L3/4U
Note: 1. The reset value for this register is device specific. Please refer to the Module Configuration section at the end of this chapter.
0x8C Analog Comparator Shift Offset Register 3 ACSHI3 Read/Write 0x00000000
0x90 Analog Comparator Shift Offset Register 4 ACSHI4 Read/Write 0x00000000
0x94 Analog Comparator Shift Offset Register 5 ACSHI5 Read/Write 0x00000000
0x98 Analog Comparator Shift Offset Register 6 ACSHI6 Read/Write 0x00000000
0x9C Analog Comparator Shift Offset Register 7 ACSHI7 Read/Write 0x00000000
0xA0 DMATouch Sensor Status Register DMATSS Read-only 0x00000000
0xF8 Parameter Register PARAMETER Read-only -(1)
0xFC Version Register VERSION Read-only -(1)
Table 31-3. CAT Register Memory Map
Offset Register Register Name Access Reset
783
32142D–06/2013
ATUC64/128/256L3/4U
31.7.1 Control Register
Name: CTRL
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• SWRST: Software reset
Writing a zero to this bit has no effect.
Writing a one to this bit resets the module. The module will be disabled after the reset.
This bit always reads as zero.
• EN: Module enable
0: Module is disabled.
1: Module is enabled.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
SWRST - - - - - - EN
784
32142D–06/2013
ATUC64/128/256L3/4U
31.7.2 Autonomous Touch Pin Selection Register
Name: ATPINS
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
• ATEN: Autonomous Touch Enable
0: Autonomous QTouch acquisition and detection is disabled.
1: Autonomous QTouch acquisition and detection is enabled using the sense pair specified in ATSP.
• ATSP: Autonomous Touch Sense Pair
Selects the sense pair that will be used by the autonomous QTouch sensor. A value of n will select sense pair n (CSAn and
CSBn pins).
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - - - - ATEN
76543210
- - - ATSP
785
32142D–06/2013
ATUC64/128/256L3/4U
31.7.3 Pin Mode Registers 0, 1, and 2
Name: PINMODE0, PINMODE1, and PINMODE2
Access Type: Read/Write
Offset: 0x08, 0x0C, 0x74
Reset Value: 0x00000000
• SP: Sense Pair Mode Selection
Each SP[n] bit determines the operation mode of sense pair n (CSAn and CSBn pins). The (PINMODE2.SP[n]
PINMODE1.SP[n] PINMODE0.SP[n]) bits have the following definitions:
000: Sense pair n disabled.
001: Sense pair n is assigned to QTouch Group A.
010: Sense pair n is assigned to QTouch Group B.
011: Sense pair n is assigned to the QMatrix Group.
100: Sense pair n is assigned to the DMATouch Group.
101: Reserved.
110: Reserved.
111: Reserved.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
- SP[16]
15 14 13 12 11 10 9 8
SP[15:8]
76543210
SP[7:0]
786
32142D–06/2013
ATUC64/128/256L3/4U
31.7.4 Autonomous/DMA Touch Configuration Register 0
Name: ATCFG0
Access Type: Read/Write
Offset: 0x10
Reset Value: 0x00000000
• DIV: Clock Divider
The prescaler is used to ensure that the CLK_CAT clock is divided to around 1 MHz to produce the sampling clock.The
prescaler uses the following formula to generate the sampling clock:
Sampling clock = CLK_CAT / (2(DIV+1))
• CHLEN: Charge Length
For the autonomous QTouch sensor and DMATouch sensors, specifies how many sample clock cycles should be used for
transferring charge to the sense capacitor.
• SELEN: Settle Length
For the autonomous QTouch sensor and DMATouch sensors, specifies how many sample clock cycles should be used for
settling after charge transfer.
31 30 29 28 27 26 25 24
DIV[15:8]
23 22 21 20 19 18 17 16
DIV[7:0]
15 14 13 12 11 10 9 8
CHLEN
76543210
SELEN
787
32142D–06/2013
ATUC64/128/256L3/4U
31.7.5 Autonomous/DMA Touch Configuration Register 1
Name: ATCFG1
Access Type: Read/Write
Offset: 0x14
Reset Value: 0x00000000
• DISHIFT: Discharge Shift
For the autonomous QTouch sensor and DMATouch sensors, specifies how many bits the DILEN field should be shifted before
using it to determine the discharge time.
• SYNC: Sync Pin
For the autonomous QTouch sensor and DMATouch sensors, specifies that acquisition shall begin when a falling edge is
received on the SYNC line.
• SPREAD: Spread Spectrum Sensor Drive
For the autonomous QTouch sensor and DMATouch sensors, specifies that spread spectrum sensor drive shall be used.
• DILEN: Discharge Length
For the autonomous QTouch sensor and DMATouch sensors, specifies how many sample clock cycles the CAT should use to
discharge the capacitors before charging them.
• MAX: Maximum Count
For the autonomous QTouch sensor and DMATouch sensors, specifies how many counts the maximum acquisition should be.
31 30 29 28 27 26 25 24
- DISHIFT - SYNC SPREAD
23 22 21 20 19 18 17 16
DILEN
15 14 13 12 11 10 9 8
MAX[15:8]
76543210
MAX[7:0]
788
32142D–06/2013
ATUC64/128/256L3/4U
31.7.6 Autonomous/DMA Touch Configuration Register 2
Name: ATCFG2
Access Type: Read/Write
Offset: 0x18
Reset Value: 0x00000000
• FILTER: Autonomous Touch Filter Setting
For the autonomous QTouch sensor and DMATouch sensors, specifies how many positive detects in a row the CAT needs to
have on the sensor before reporting it as a touch. A FILTER value of 0 is not allowed and will result in undefined behavior.
• OUTSENS: Out-of-Touch Sensitivity
For the autonomous QTouch sensor and DMATouch sensors, specifies how sensitive the out-of-touch detector should be.
• SENSE: Sensitivity
For the autonomous QTouch sensor and DMATouch sensors, specifies how sensitive the touch detector should be.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
- FILTER
15 14 13 12 11 10 9 8
OUTSENS
76543210
SENSE
789
32142D–06/2013
ATUC64/128/256L3/4U
31.7.7 Autonomous/DMA Touch Configuration Register 3
Name: ATCFG3
Access Type: Read/Write
Offset: 0x1C
Reset Value: 0x00000000
• PTHR: Positive Recalibration Threshold
For the autonomous QTouch sensor and DMATouch sensors, specifies how far a sensor’s signal must move in a positive
direction from the reference in order to cause a recalibration.
• PDRIFT: Positive Drift Compensation
For the autonomous QTouch sensor and DMATouch sensors, specifies how often a positive drift compensation should be
performed. When this field is zero, positive drift compensation will never be performed. When this field is non-zero, the positive
drift compensation time interval is given by the following formula:
Tpdrift = PDRIFT * 65536 * (sample clock period)
• NDRIFT: Negative Drift Compensation
For the autonomous QTouch sensor and DMATouch sensors, specifies how often a negative drift compensation should be
performed. When this field is zero, negative drift compensation will never be performed. When this field is non-zero, the negative
drift compensation time interval is given by the following formula:
Tndrift = NDRIFT * 65536 * (sample clock period)
With the typical sample clock frequency of 1 MHz, PDRIFT and NDRIFT can be set from 0.066 seconds to 16.7 seconds
with 0.066 second resolution.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
PTHR
15 14 13 12 11 10 9 8
PDRIFT
76543210
NDRIFT
790
32142D–06/2013
ATUC64/128/256L3/4U
31.7.8 Touch Group x Configuration Register 0
Name: TGxCFG0
Access Type: Read/Write
Offset: 0x20, 0x28
Reset Value: 0x00000000
• DIV: Clock Divider
The prescaler is used to ensure that the CLK_CAT clock is divided to around 1 MHz to produce the sampling clock.The
prescaler uses the following formula to generate the sampling clock:
Sampling clock = CLK_CAT / (2(DIV+1))
• CHLEN: Charge Length
For the QTouch method, specifies how many sample clock cycles should be used for transferring charge to the sense capacitor.
• SELEN: Settle Length
For the QTouch method, specifies how many sample clock cycles should be used for settling after charge transfer.
31 30 29 28 27 26 25 24
DIV[15:8]
23 22 21 20 19 18 17 16
DIV[7:0]
15 14 13 12 11 10 9 8
CHLEN
76543210
SELEN
791
32142D–06/2013
ATUC64/128/256L3/4U
31.7.9 Touch Group x Configuration Register 1
Name: TGxCFG1
Access Type: Read/Write
Offset: 0x24, 0x2C
Reset Value: 0x00000000
• DISHIFT: Discharge Shift
For the sensors in QTouch group x, specifies how many bits the DILEN field should be shifted before using it to determine the
discharge time.
• SYNC: Sync Pin
For sensors in QTouch group x, specifies that acquisition shall begin when a falling edge is received on the SYNC line.
• SPREAD: Spread Spectrum Sensor Drive
For sensors in QTouch group x, specifies that spread spectrum sensor drive shall be used.
• DILEN: Discharge Length
For sensors in QTouch group x, specifies how many clock cycles the CAT should use to discharge the capacitors before
charging them.
• MAX: Touch Maximum Count
For sensors in QTouch group x, specifies how many counts the maximum acquisition should be.
31 30 29 28 27 26 25 24
- - DISHIFT - - SYNC SPREAD
23 22 21 20 19 18 17 16
DILEN
15 14 13 12 11 10 9 8
MAX[15:8]
76543210
MAX[7:0]
792
32142D–06/2013
ATUC64/128/256L3/4U
31.7.10 Matrix Group Configuration Register 0
Name: MGCFG0
Access Type: Read/Write
Offset: 0x30
Reset Value: 0x00000000
• DIV: Clock Divider
The prescaler is used to ensure that the CLK_CAT clock is divided to around 4 MHz to produce the burst timing clock.The
prescaler uses the following formula to generate the burst timing clock:
Burst timing clock = CLK_CAT / (2(DIV+1))
• CHLEN: Charge Length
For QMatrix sensors, specifies how many burst prescaler clock cycles should be used for transferring charge to the sense
capacitor.
• SELEN: Settle Length
For QMatrix sensors, specifies how many burst prescaler clock cycles should be used for settling after charge transfer.
31 30 29 28 27 26 25 24
DIV[15:8]
23 22 21 20 19 18 17 16
DIV[7:0]
15 14 13 12 11 10 9 8
CHLEN
76543210
SELEN
793
32142D–06/2013
ATUC64/128/256L3/4U
31.7.11 Matrix Group Configuration Register 1
Name: MGCFG1
Access Type: Read/Write
Offset: 0x34
Reset Value: 0x00000000
• DISHIFT: Discharge Shift
For QMatrix sensors, specifies how many bits the DILEN field should be shifted before using it to determine the discharge time.
• SYNC: Sync Pin
For QMatrix sensors, specifies that acquisition shall begin when a falling edge is received on the SYNC line.
• SPREAD: Spread Spectrum Sensor Drive
For QMatrix sensors, specifies that spread spectrum sensor drive shall be used.
• DILEN: Discharge Length
For QMatrix sensors, specifies how many burst prescaler clock cycles the CAT should use to discharge the capacitors at the
beginning of a burst sequence.
• MAX: Maximum Count
For QMatrix sensors, specifies how many counts the maximum acquisition should be.
31 30 29 28 27 26 25 24
- DISHIFT - SYNC SPREAD
23 22 21 20 19 18 17 16
DILEN
15 14 13 12 11 10 9 8
MAX[15:8]
76543210
MAX[7:0]
794
32142D–06/2013
ATUC64/128/256L3/4U
31.7.12 Matrix Group Configuration Register 2
Name: MGCFG2
Access Type: Read/Write
Offset: 0x38
Reset Value: 0x00000000
• ACCTRL: Analog Comparator Control
When written to one, allows the CAT to disable the analog comparators when they are not needed. When written to zero, the
analog comparators are always enabled.
• CONSEN: Consensus Filter Length
For QMatrix sensors, specifies that discharge will be terminated when CONSEN out of the most recent 5 comparator samples
are positive. For example, a value of 3 in the CONSEN field will terminate discharge when 3 out of the most recent 5 comparator
samples are positive. When CONSEN has the default value of 0, discharge will be terminated immediately when the comparator
output goes positive.
• CXDILEN: Cx Capacitor Discharge Length
For QMatrix sensors, specifies how many burst prescaler clock cycles the CAT should use to discharge the Cx capacitor at the
end of each burst cycle.
• SYNCTIM: Sync Time Interval
When non-zero, determines the number of prescaled clock cycles between the start of the acquisition on each X line for QMatrix
acquisition.
31 30 29 28 27 26 25 24
ACCTRL CONSEN -
23 22 21 20 19 18 17 16
CXDILEN
15 14 13 12 11 10 9 8
- SYNCTIM[11:8]
76543210
SYNCTIM[7:0]
795
32142D–06/2013
ATUC64/128/256L3/4U
31.7.13 Status Register
Name: SR
Access Type: Read-only
Offset: 0x3C
Reset Value: 0x00000000
• DMATSC: DMATouch Sensor State Change
0: No change in the DMATSS register.
1: One or more bits have changed in the DMATSS register.
• DMATSR: DMATouch State Read Register Ready
0: A new state word is not available in the DMATSR register.
1: A new state word is available in the DMATSR register.
• DMATSW: DMATouch State Write Register Request
0: The DMATouch algorithm is not requesting that a state word be written to the DMATSW register.
1: The DMATouch algorithm is requesting that a state word be written to the DMATSW register.
• ACQDONE: Acquisition Done
0: Acquisition is not done (still in progress).
1: Acquisition is complete.
• ACREADY: Acquired Count Data is Ready
0: Acquired count data is not available in the ACOUNT register.
1: Acquired count data is available in the ACOUNT register.
• MBLREQ: Matrix Burst Length Required
0: The QMatrix acquisition does not require any burst lengths.
1: The QMatrix acquisition requires burst lengths for the current X line.
• ATSTATE: Autonomous Touch Sensor State
0: The autonomous QTouch sensor is not active.
1: The autonomous QTouch sensor is active.
• ATSC: Autonomous Touch Sensor Status Interrupt
0: No status change in the autonomous QTouch sensor.
1: Status change in the autonomous QTouch sensor.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
DMATSC - - - - - DMATSR DMATSW
15 14 13 12 11 10 9 8
- - - - - - ACQDONE ACREADY
76543210
- - - MBLREQ ATSTATE ATSC ATCAL ENABLED
796
32142D–06/2013
ATUC64/128/256L3/4U
• ATCAL: Autonomous Touch Calibration Ongoing
0: The autonomous QTouch sensor is not calibrating.
1: The autonomous QTouch sensor is calibrating.
• ENABLED: Module Enabled
0: The module is disabled.
1: The module is enabled.
797
32142D–06/2013
ATUC64/128/256L3/4U
31.7.14 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x40
Reset Value: -
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
DMATSC - - - - - - -
15 14 13 12 11 10 9 8
- - - - - - ACQDONE ACREADY
76543210
- - - - - ATSC ATCAL -
798
32142D–06/2013
ATUC64/128/256L3/4U
31.7.15 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x44
Reset Value: -
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
DMATSC - - - - - - -
15 14 13 12 11 10 9 8
- - - - - - ACQDONE ACREADY
76543210
- - - - - ATSC ATCAL -
799
32142D–06/2013
ATUC64/128/256L3/4U
31.7.16 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x48
Reset Value: -
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
DMATSC - - - - - - -
15 14 13 12 11 10 9 8
- - - - - - ACQDONE ACREADY
76543210
- - - - - ATSC ATCAL -
800
32142D–06/2013
ATUC64/128/256L3/4U
31.7.17 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x4C
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
DMATSC - - - - - - -
15 14 13 12 11 10 9 8
- - - - - - ACQDONE ACREADY
76543210
- - - - - ATSC ATCAL -
801
32142D–06/2013
ATUC64/128/256L3/4U
31.7.18 Acquisition Initiation and Selection Register
Name: AISR
Access Type: Read/Write
Offset: 0x50
Reset Value: 0x00000000
• ACQSEL: Acquisition Type Selection
A write to this register initiates an acquisition of the following type:
00: QTouch Group A.
01: QTouch Group B.
10: QMatrix Group.
11: Undefined behavior.
A read of this register will return the value that was previously written.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
-
15 14 13 12 11 10 9 8
-
76543210
- ACQSEL
802
32142D–06/2013
ATUC64/128/256L3/4U
31.7.19 Acquired Count Register
Name: ACOUNT
Access Type: Read-only
Offset: 0x54
Reset Value: 0x00000000
• Y: Y index
The Y index (for QMatrix method) associated with this count value.
• SPORX: Sensor pair or X index
The sensor pair index (for QTouch method) or X index (for QMatrix method) associated with this count value.
• COUNT: Count value
The signal (number of counts) acquired on the channel specified in the SPORX and Y fields.
When multiple acquired count values are read from a QTouch acquisition, the Y field will always be 0 and the SPORX value will
increase monotonically. For example, suppose a QTouch acquisition is performed using sensor pairs SP1, SP4, and SP9. The
first count read will have SPORX=1, the second read will have SPORX=4, and the third read will have SPORX=9.
When multiple acquired count values are read from a QMatrix acquisition, the SPORX value will stay the same while Y
increases monotonically through all Y values in the group. Then SPORX will increase to the next X value in the group. For
example, a QMatrix acquisition with X=2,3 and Y=4,7 would provide count values in the following order: X=2 and Y=4, then X=2
and Y=7, then X=3 and Y=4, and finally X=3 and Y=7.
31 30 29 28 27 26 25 24
Y
23 22 21 20 19 18 17 16
SPORX
15 14 13 12 11 10 9 8
COUNT[15:8]
76543210
COUNT[7:0]
803
32142D–06/2013
ATUC64/128/256L3/4U
31.7.20 Matrix Burst Length Register
Name: MBLEN
Access Type: Write-only
Offset: 0x58
Reset Value: -
• BURSTx: Burst Length x
For QMatrix sensors, specifies how many times the switching sequence should be repeated before acquisition begins for each
channel. Each count in the BURSTx field specifies 1 repeat of the switching sequence, so the actual burst length will be BURST.
Before doing a QMatrix acquisition on one X line this register has to be written with the burst values for the current XY pairs. For
each X line this register needs to be programmed with all the Y values. If Y values larger than 3 are used the register has to be
written several times in order to specify all burst lengths.
The Status Register bit MBLREQ is set to 1 when the CAT is waiting for values to be written into this register.
31 30 29 28 27 26 25 24
BURST0
23 22 21 20 19 18 17 16
BURST1
15 14 13 12 11 10 9 8
BURST2
76543210
BURST3
804
32142D–06/2013
ATUC64/128/256L3/4U
31.7.21 Discharge Current Source Register
Name: DICS
Access Type: Read/Write
Offset: 0x5C
Reset Value: 0x00000000
• FSOURCES: Force Discharge Current Sources
When FSOURCES[n] is 0, the corresponding discharge current source behavior depends on SOURCES[n].
When FSOURCES[n] is 1, the corresponding discharge current source is forced to be enabled continuously. This is useful for
testing or debugging but should not be done during normal acquisition.
• GLEN: Global Enable
0: The current source module is globally disabled.
1: The current source module is globally enabled.
• INTVREFSEL: Internal Voltage Reference Select
0: The voltage for the reference resistor is generated from the internal band gap circuit.
1: The voltage for the reference resistor is VDDIO/3.
• INTREFSEL: Internal Reference Select
0: The reference current flows through an external resistor on the DIS pin.
1: The reference current flows through the internal reference resistor.
• TRIM: Reference Current Trimming
This field is used to trim the discharge current. 0x00 corresponds to the minimum current value, and 0x1F corresponds to the
maximum current value.
• SOURCES: Enable Discharge Current Sources
When SOURCES[n] is 0, the corresponding discharge current source is disabled.
When SOURCES[n] is 1, the corresponding discharge current source is enabled at appropriate times during acquisition.
31 30 29 28 27 26 25 24
FSOURCES[7:0]
23 22 21 20 19 18 17 16
GLEN - - - - - INTVREFSEL INTREFSEL
15 14 13 12 11 10 9 8
- - - TRIM
76543210
SOURCES[7:0]
805
32142D–06/2013
ATUC64/128/256L3/4U
31.7.22 Spread Spectrum Configuration Register
Name: SSCFG
Access Type: Read/Write
Offset: 0x60
Reset Value: 0x00000000
• MAXDEV: Maximum Deviation
When spread spectrum burst is enabled, MAXDEV indicates the maximum number of prescaled clock cycles the burst pulse will
be extended or shortened.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
MAXDEV
806
32142D–06/2013
ATUC64/128/256L3/4U
31.7.23 CSA Resistor Control Register
Name: CSARES
Access Type: Read/Write
Offset: 0x64
Reset Value: 0x00000000
• RES: Resistive Drive Enable
When RES[n] is 0, CSA[n] has the same drive properties as normal I/O pads.
When RES[n] is 1, CSA[n] has a nominal output resistance of 1kOhm during the burst phase.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
- RES[16]
15 14 13 12 11 10 9 8
RES[15:8]
76543210
RES[7:0]
807
32142D–06/2013
ATUC64/128/256L3/4U
31.7.24 CSB Resistor Control Register
Name: CSBRES
Access Type: Read/Write
Offset: 0x68
Reset Value: 0x00000000
• RES: Resistive Drive Enable
When RES[n] is 0, CSB[n] has the same drive properties as normal I/O pads.
When RES[n] is 1, CSB[n] has a nominal output resistance of 1kOhm during the burst phase.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
- RES[16]
15 14 13 12 11 10 9 8
RES[15:8]
76543210
RES[7:0]
808
32142D–06/2013
ATUC64/128/256L3/4U
31.7.25 Autonomous Touch Base Count Register
Name: ATBASE
Access Type: Read-only
Offset: 0x6C
Reset Value: 0x00000000
• COUNT: Count value
The base count currently stored by the autonomous touch sensor. This is useful for autonomous touch debugging purposes.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
-
15 14 13 12 11 10 9 8
COUNT[15:8]
76543210
COUNT[7:0]
809
32142D–06/2013
ATUC64/128/256L3/4U
31.7.26 Autonomous Touch Current Count Register
Name: ATCURR
Access Type: Read-only
Offset: 0x70
Reset Value: 0x00000000
• COUNT: Count value
The current count acquired by the autonomous touch sensor. This is useful for autonomous touch debugging purposes.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
-
15 14 13 12 11 10 9 8
COUNT[15:8]
76543210
COUNT[7:0]
810
32142D–06/2013
ATUC64/128/256L3/4U
31.7.27 DMATouch State Write Register
Name: DMATSW
Access Type: Write-only
Offset: 0x78
Reset Value: 0x00000000
• NOTINCAL: Not in Calibration Mode
0: Calibration should be performed on the next iteration of the DMATouch algorithm.
1: Calibration should not be performed on the next iteration of the DMATouch algorithm.
• DETCNT: Detection Count
This count value is updated and used by the DMATouch algorithm in order to detect when a button has been pushed.
• BASECNT: Base Count
This count value represents the average expected acquired count when the sensor/button is not pushed.
31 30 29 28 27 26 25 24
- - - - - - - NOTINCAL
23 22 21 20 19 18 17 16
DETCNT[23:16]
15 14 13 12 11 10 9 8
BASECNT[15:8]
76543210
BASECNT[7:0]
811
32142D–06/2013
ATUC64/128/256L3/4U
31.7.28 DMA Touch State Read Register
Name: DMATSR
Access Type: Read/Write
Offset: 0x7C
Reset Value: 0x00000000
• NOTINCAL: Not in Calibration Mode
0: Calibration should be performed on the next iteration of the DMATouch algorithm.
1: Calibration should not be performed on the next iteration of the DMATouch algorithm.
• DETCNT: Detection Count
This count value is updated and used by the DMATouch algorithm in order to detect when a button has been pushed.
• BASECNT: Base Count
This count value represents the average expected acquired count when the sensor/button is not pushed.
31 30 29 28 27 26 25 24
- - - - - - - NOTINCAL
23 22 21 20 19 18 17 16
DETCNT[23:16]
15 14 13 12 11 10 9 8
BASECNT[15:8]
76543210
BASECNT[7:0]
812
32142D–06/2013
ATUC64/128/256L3/4U
31.7.29 Analog Comparator Shift Offset Register x
Name: ACSHIx
Access Type: Read/Write
Offset: 0x80, 0x84, 0x88, 0x8C, 0x90, 0x94, 0x98, and 0x9C
Reset Value: 0x00000000
• SHIVAL: Shift Offset Value
Specifies the amount to shift the count value from each comparator. This allows the offset of each comparator to be
compensated.
31 30 29 28 27 26 25 24
-
23 22 21 20 19 18 17 16
-
15 14 13 12 11 10 9 8
- SHIVAL[11:8]
76543210
SHIVAL[7:0]
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31.7.30 DMATouch Sensor Status Register
Name: DMATSS
Access Type: Read-only
Offset: 0xA0
Reset Value: 0x00000000
• SS: Sensor Status
0: The DMATouch sensor is not active, i.e. the button is currently not pushed.
1: The DMATouch sensor is active, i.e. the button is currently pushed.
31 30 29 28 27 26 25 24
SS[31:24]
23 22 21 20 19 18 17 16
SS[23:16]
15 14 13 12 11 10 9 8
SS[15:8]
76543210
SS[7:0]
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31.7.31 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0xF8
Reset Value: -
• SP[n]: Sensor pair implemented
0: The corresponding sensor pair is not implemented
1: The corresponding sensor pair is implemented.
31 30 29 28 27 26 25 24
SP[31:24]
23 22 21 20 19 18 17 16
SP[23:16]
15 14 13 12 11 10 9 8
SP[15:8]
76543210
SP[7:0]
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31.7.32 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0xFC
Reset Value: -
• VARIANT: Variant number
Reserved. No functionality associated.
• VERSION: Version number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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31.8 Module Configuration
The specific configuration the CAT module is listed in the following tables.The module bus
clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
31.8.1 Resistive Drive
By default, the CAT pins are driven with normal I/O drive properties. Some of the CSA and CSB
pins can optionally drive with a 1k output resistance for improved EMC.
To enable resistive drive on a pin, the user must write a one to the corresponding bit in the CSA
Resistor Control Register (CSARES) or CSB Resistor Control Register (CSBRES) register.
Table 31-4. CAT Configuration
Feature CAT
Number of touch sensors/Size of matrix Allows up to 17 touch sensors, or up to 16 by 8
matrix sensors to be interfaced.
Table 31-5. CAT Clocks
Clock Name Description
CLK_CAT Clock for the CAT bus interface
GCLK The generic clock used for the CAT is GCLK4
Table 31-6. Register Reset Values
Register Reset Value
VERSION 0x00000400
PARAMETER 0x0001FFFF
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32. Glue Logic Controller (GLOC)
Rev: 1.0.0.0
32.1 Features
• Glue logic for general purpose PCB design
• Programmable lookup table
• Up to four inputs supported per lookup table
• Optional filtering of output
32.2 Overview
The Glue Logic Controller (GLOC) contains programmable logic which can be connected to the
device pins. This allows the user to eliminate logic gates for simple glue logic functions on the
PCB.
The GLOC consists of a number of lookup table (LUT) units. Each LUT can generate an output
as a user programmable logic expression with four inputs. Inputs can be individually masked.
The output can be combinatorially generated from the inputs, or filtered to remove spikes.
32.3 Block Diagram
Figure 32-1. GLOC Block Diagram PERIPHERAL BUS TRUTH
FILTER
OUT[0]
...
OUT[n]
FILTEN
IN[3:0]
…
IN[(4n+3):4n]
AEN
CLK_GLOC
GCLK
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32.4 I/O Lines Description
Each LUT have 4 inputs and one output. The inputs and outputs for the LUTs are mapped
sequentially to the inputs and outputs. This means that LUT0 is connected to IN0 to IN3 and
OUT0. LUT1 is connected to IN4 to IN7 and OUT1. In general, LUTn is connected to IN[4n] to
IN[4n+3] and OUTn.
32.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
32.5.1 I/O Lines
The pins used for interfacing the GLOC may be multiplexed with I/O Controller lines. The programmer
must first program the I/O Controller to assign the desired GLOC pins to their
peripheral function. If I/O lines of the GLOC are not used by the application, they can be used for
other purposes by the I/O Controller.
It is only required to enable the GLOC inputs and outputs actually in use. Pullups for pins configured
to be used by the GLOC will be disabled.
32.5.2 Clocks
The clock for the GLOC bus interface (CLK_GLOC) is generated by the Power Manager. This
clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to disable
the GLOC before disabling the clock, to avoid freezing the module in an undefined state.
Additionally, the GLOC depends on a dedicated Generic Clock (GCLK). The GCLK can be set to
a wide range of frequencies and clock sources, and must be enabled by the System Control
Interface (SCIF) before the GLOC filter can be used.
32.5.3 Debug Operation
When an external debugger forces the CPU into debug mode, the GLOC continues normal
operation.
32.6 Functional Description
32.6.1 Enabling the Lookup Table Inputs
Since the inputs to each lookup table (LUT) unit can be multiplexed with other peripherals, each
input must be explicitly enabled by writing a one to the corresponding enable bit (AEN) in the
corresponding Control Register (CR).
If no inputs are enabled, the output OUTn will be the least significant bit in the TRUTHn register.
Table 32-1. I/O Lines Description
Pin Name Pin Description Type
IN0-INm Inputs to lookup tables Input
OUT0-OUTn Output from lookup tables Output
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32.6.2 Configuring the Lookup Table
The lookup table in each LUT unit can generate any logic expression OUT as a function of up to
four inputs, IN[3:0]. The truth table for the expression is written to the TRUTH register for the
LUT. Table 32-2 shows the truth table for LUT0. The truth table for LUTn is written to TRUTHn,
and the corresponding input and outputs will be IN[4n] to IN[4n+3] and OUTn.
32.6.3 Output Filter
By default, the output OUTn is a combinatorial function of the inputs IN[4n] to IN[4n+3]. This may
cause some short glitches to occur when the inputs change value.
It is also possible to clock the output through a filter to remove glitches. This requires that the
corresponding generic clock (GCLK) has been enabled before use. The filter can then be
enabled by writing a one to the Filter Enable (FILTEN) bit in CRn. The OUTn output will be
delayed by three to four GCLK cycles when the filter is enabled.
Table 32-2. Truth Table for the Lookup Table in LUT0
IN[3] IN[2] IN[1] IN[0] OUT[0]
0 0 0 0 TRUTH0[0]
0 0 0 1 TRUTH0[1]
0 0 1 0 TRUTH0[2]
0 0 1 1 TRUTH0[3]
0 1 0 0 TRUTH0[4]
0 1 0 1 TRUTH0[5]
0 1 1 0 TRUTH0[6]
0 1 1 1 TRUTH0[7]
1 0 0 0 TRUTH0[8]
1 0 0 1 TRUTH0[9]
1 0 1 0 TRUTH0[10]
1 0 1 1 TRUTH0[11]
1 1 0 0 TRUTH0[12]
1 1 0 1 TRUTH0[13]
1 1 1 0 TRUTH0[14]
1 1 1 1 TRUTH0[15]
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32.7 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 32-3. GLOC Register Memory Map
Offset Register Register Name Access Reset
0x00+n*0x08 Control Register n CRn Read/Write 0x00000000
0x04+n*0x08 Truth Table Register n TRUTHn Read/Write 0x00000000
0x38 Parameter Register PARAMETER Read-only - (1)
0x3C Version Register VERSION Read-only - (1)
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32.7.1 Control Register n
Name: CRn
Access Type: Read/Write
Offset: 0x00+n*0x08
Reset Value: 0x00000000
• FILTEN: Filter Enable
1: The output is glitch filtered
0: The output is not glitch filtered
• AEN: Enable IN Inputs
Input IN[n] is enabled when AEN[n] is one.
Input IN[n] is disabled when AEN[n] is zero, and will not affect the OUT value.
31 30 29 28 27 26 25 24
FILTEN - - - - - - -
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - AEN
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32.7.2 Truth Table Register n
Name: TRUTHn
Access Type: Read/Write
Offset: 0x04+n*0x08
Reset Value: 0x00000000
• TRUTH: Truth Table Value
This value defines the output OUT as a function of inputs IN:
OUT = TRUTH[IN]
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
TRUTH[15:8]
76543210
TRUTH[7:0]
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32.7.3 Parameter Register
Name: PARAMETER
Access Type: Read-only
Offset: 0x38
Reset Value: -
• LUTS: Lookup Table Units Implemented
This field contains the number of lookup table units implemented in this device.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
LUTS
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32.7.4 VERSION Register
Name: VERSION
Access Type: Read-only
Offset: 0x3C
Reset Value: -
• VARIANT: Variant Number
Reserved. No functionality associated.
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
- - - - VARIANT
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
825
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ATUC64/128/256L3/4U
32.8 Module Configuration
The specific configuration for each GLOC instance is listed in the following tables.The GLOC
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 32-4. GLOC Configuration
Feature GLOC
Number of LUT units 2
Table 32-5. GLOC Clocks
Clock Name Description
CLK_GLOC Clock for the GLOC bus interface
GCLK The generic clock used for the GLOC is GCLK5
Table 32-6. Register Reset Values
Register Reset Value
VERSION 0x00000100
PARAMETER 0x00000002
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33. aWire UART (AW)
Rev: 2.3.0.0
33.1 Features
• Asynchronous receiver or transmitter when the aWire system is not used for debugging.
• One- or two-pin operation supported.
33.2 Overview
If the AW is not used for debugging, the aWire UART can be used by the user to send or receive
data with one start bit, eight data bits, no parity bits, and one stop bit. This can be controlled
through the aWire UART user interface.
This chapter only describes the aWire UART user interface. For a description of the aWire
Debug Interface, please see the Programming and Debugging chapter.
33.3 Block Diagram
Figure 33-1. aWire Debug Interface Block Diagram
UART
Reset
filter
External reset
AW_ENABLE
RESET_N
Baudrate Detector
RW SZ ADDR DATA
CRC
AW CONTROL
AW User Interface
SAB interface
RESET command
Power
Manager
HALT command CPU
Flash
Controller CHIP_ERASE command
aWire Debug Interface
PB
SAB
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33.4 I/O Lines Description
33.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
33.5.1 I/O Lines
The pin used by AW is multiplexed with the RESET_N pin. The reset functionality is the default
function of this pin. To enable the aWire functionality on the RESET_N pin the user must enable
the aWire UART user interface.
33.5.2 Power Management
If the CPU enters a sleep mode that disables clocks used by the aWire UART user interface, the
aWire UART user interface will stop functioning and resume operation after the system wakes
up from sleep mode.
33.5.3 Clocks
The aWire UART uses the internal 120 MHz RC oscillator (RC120M) as clock source for its
operation. When using the aWire UART user interface RC120M must enabled using the Clock
Request Register (see Section 33.6.1).
The clock for the aWire UART user interface (CLK_AW) is generated by the Power Manager.
This clock is enabled at reset, and can be disabled in the Power Manager. It is recommended to
disable the aWire UART user interface before disabling the clock, to avoid freezing the aWire
UART user interface in an undefined state.
33.5.4 Interrupts
The aWire UART user interface interrupt request line is connected to the interrupt controller.
Using the aWire UART user interface interrupt requires the interrupt controller to be programmed
first.
33.5.5 Debug Operation
If the AW is used for debugging the aWire UART user interface will not be usable.
When an external debugger forces the CPU into debug mode, the aWire UART user interface
continues normal operation. If the aWire UART user interface is configured in a way that
requires it to be periodically serviced by the CPU through interrupts or similar, improper operation
or data loss may result during debugging.
33.5.6 External Components
The AW needs an external pullup on the RESET_N pin to ensure that the pin is pulled up when
the bus is not driven.
33.6 Functional Description
The aWire UART user interface can be used as a spare Asynchronous Receiver or Transmitter
when AW is not used for debugging.
Table 33-1. I/O Lines Description
Name Description Type
DATA aWire data multiplexed with the RESET_N pin. Input/Output
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33.6.1 How to Initialize The Module
To initialize the aWire UART user interface the user must first enable the clock by writing a one
to the Clock Enable bit in the Clock Request Register (CLKR.CLKEN) and wait for the Clock
Enable bit in the Status Register (SR.CENABLED) to be set. After doing this either receive,
transmit or receive with resync must be selected by writing the corresponding value into the
Mode field of the Control (CTRL.MODE) Register. Due to the RC120M being asynchronous with
the system clock values must be allowed to propagate in the system. During this time the aWire
master will set the Busy bit in the Status Register (SR.BUSY).
After the SR.BUSY bit is cleared the Baud Rate field in the Baud Rate Register (BRR.BR) can
be written with the wanted baudrate ( ) according to the following formula ( is the RC120M
clock frequency):
After this operation the user must wait until the SR.BUSY is cleared. The interface is now ready
to be used.
33.6.2 Basic Asynchronous Receiver Operation
The aWire UART user interface must be initialized according to the sequence above, but the
CTRL.MODE field must be written to one (Receive mode).
When a data byte arrives the aWire UART user interface will indicate this by setting the Data
Ready Interrupt bit in the Status Register (SR.DREADYINT). The user must read the Data in the
Receive Holding Register (RHR.RXDATA) and clear the Interrupt bit by writing a one to the Data
Ready Interrupt Clear bit in the Status Clear Register (SCR.DREADYINT). The interface is now
ready to receive another byte.
33.6.3 Basic Asynchronous Transmitter Operation
The aWire UART user interface must be initialized according to the sequence above, but the
CTRL.MODE field must be written to two (Transmit mode).
To transmit a data byte the user must write the data to the Transmit Holding Register
(THE.TXDATA). Before the next byte can be written the SR.BUSY must be cleared.
33.6.4 Basic Asynchronous Receiver with Resynchronization
By writing three into CTRL.MODE the aWire UART user interface will assume that the first byte
it receives is a sync byte (0x55) and set BRR.BR according to this. All subsequent transfers will
assume this baudrate, unless BRR.BR is rewritten by the user.
To make the aWire UART user interface accept a new sync resynchronization the aWire UART
user interface must be disabled by writing zero to CTRL.MODE and then reenable the interface.
33.6.5 Overrun
In Receive mode an overrun can occur if the user has not read the previous received data from
the RHR.RXDATA when the newest data should be placed there. Such a condition is flagged by
setting the Overrun bit in the Status Register (SR.OVERRUN). If SR.OVERRUN is set the newest
data received is placed in RHR.RXDATA and the data that was there before is overwritten.
f
br f
aw
f
br
8f
aw
BR = -----------
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33.6.6 Interrupts
To make the CPU able to do other things while waiting for the aWire UART user interface to finish
its operations the aWire UART user interface supports generating interrupts. All status bits in
the Status Register can be used as interrupt sources, except the SR.BUSY and SR.CENABLED
bits.
To enable an interrupt the user must write a one to the corresponding bit in the Interrupt Enable
Register (IER). Upon the next zero to one transition of this SR bit the aWire UART user interface
will flag this interrupt to the CPU. To clear the interrupt the user must write a one to the corresponding
bit in the Status Clear Register (SCR).
Interrupts can be disabled by writing a one to the corresponding bit in the Interrupt Disable Register
(IDR). The interrupt Mask Register (IMR) can be read to check if an interrupt is enabled or
disabled.
33.6.7 Using the Peripheral DMA Controller
To relieve the CPU of data transfers the aWire UART user interface support using the Peripheral
DMA controller.
To transmit using the Peripheral DMA Controller do the following:
1. Setup the aWire UART user interface in transmit mode.
2. Setup the Peripheral DMA Controller with buffer address and length, use byte as transfer
size.
3. Enable the Peripheral DMA Controller.
4. Wait until the Peripheral DMA Controller is done.
To receive using the Peripheral DMA Controller do the following:
1. Setup the aWire UART user interface in receive mode
2. Setup the Peripheral DMA Controller with buffer address and length, use byte as transfer
size.
3. Enable the Peripheral DMA Controller.
4. Wait until the Peripheral DMA Controller is ready.
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33.7 User Interface
Note: 1. The reset values are device specific. Please refer to the Module Configuration section at the end of this chapter.
Table 33-2. aWire UART user interface Register Memory Map
Offset Register Register Name Access Reset
0x00 Control Register CTRL Read/Write 0x00000000
0x04 Status Register SR Read-only 0x00000000
0x08 Status Clear Register SCR Write-only -
0x0C Interrupt Enable Register IER Write-only -
0x10 Interrupt Disable Register IDR Write-only -
0x14 Interrupt Mask Register IMR Read-only 0x00000000
0x18 Receive Holding Register RHR Read-only 0x00000000
0x1C Transmit Holding Register THR Read/Write 0x00000000
0x20 Baud Rate Register BRR Read/Write 0x00000000
0x24 Version Register VERSION Read-only -(1)
0x28 Clock Request Register CLKR Read/Write 0x00000000
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33.7.1 Control Register
Name: CTRL
Access Type: Read/Write
Offset: 0x00
Reset Value: 0x00000000
• MODE: aWire UART user interface mode
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - MODE
Table 33-3. aWire UART user interface Modes
MODE Mode Description
0 Disabled
1 Receive
2 Transmit
3 Receive with resync.
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33.7.2 Status Register
Name: SR
Access Type: Read-only
Offset: 0x04
Reset Value: 0x00000000
• TRMIS: Transmit Mismatch
0: No transfers mismatches.
1: The transceiver was active when receiving.
This bit is set when the transceiver is active when receiving.
This bit is cleared when corresponding bit in SCR is written to one.
• OVERRUN: Data Overrun
0: No data overwritten in RHR.
1: Data in RHR has been overwritten before it has been read.
This bit is set when data in RHR is overwritten before it has been read.
This bit is cleared when corresponding bit in SCR is written to one.
• DREADYINT: Data Ready Interrupt
0: No new data in the RHR.
1: New data received and placed in the RHR.
This bit is set when new data is received and placed in the RHR.
This bit is cleared when corresponding bit in SCR is written to one.
• READYINT: Ready Interrupt
0: The interface has not generated an ready interrupt.
1: The interface has had a transition from busy to not busy.
This bit is set when the interface has transition from busy to not busy.
This bit is cleared when corresponding bit in SCR is written to one.
• CENABLED: Clock Enabled
0: The aWire clock is not enabled.
1: The aWire clock is enabled.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - TRMIS - - OVERRUN DREADYINT READYINT
76543210
- - - - - CENABLED - BUSY
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This bit is set when the clock is disabled.
This bit is cleared when the clock is enabled.
• BUSY: Synchronizer Busy
0: The asynchronous interface is ready to accept more data.
1: The asynchronous interface is busy and will block writes to CTRL, BRR, and THR.
This bit is set when the asynchronous interface becomes busy.
This bit is cleared when the asynchronous interface becomes ready.
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33.7.3 Status Clear Register
Name: SCR
Access Type: Write-only
Offset: 0x08
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in SR and the corresponding interrupt request.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - TRMIS - - OVERRUN DREADYINT READYINT
76543210
--------
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33.7.4 Interrupt Enable Register
Name: IER
Access Type: Write-only
Offset: 0x0C
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will set the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - TRMIS - - OVERRUN DREADYINT READYINT
76543210
--------
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33.7.5 Interrupt Disable Register
Name: IDR
Access Type: Write-only
Offset: 0x10
Reset Value: 0x00000000
Writing a zero to a bit in this register has no effect.
Writing a one to a bit in this register will clear the corresponding bit in IMR.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - TRMIS - - OVERRUN DREADYINT READYINT
76543210
--------
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33.7.6 Interrupt Mask Register
Name: IMR
Access Type: Read-only
Offset: 0x14
Reset Value: 0x00000000
0: The corresponding interrupt is disabled.
1: The corresponding interrupt is enabled.
A bit in this register is cleared when the corresponding bit in IDR is written to one.
A bit in this register is set when the corresponding bit in IER is written to one.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - TRMIS - - OVERRUN DREADYINT READYINT
76543210
--------
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ATUC64/128/256L3/4U
33.7.7 Receive Holding Register
Name: RHR
Access Type: Read-only
Offset: 0x18
Reset Value: 0x00000000
• RXDATA: Received Data
The last byte received.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
RXDATA
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33.7.8 Transmit Holding Register
Name: THR
Access Type: Read/Write
Offset: 0x1C
Reset Value: 0x00000000
• TXDATA: Transmit Data
The data to send.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
TXDATA
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ATUC64/128/256L3/4U
33.7.9 Baud Rate Register
Name: BRR
Access Type: Read/Write
Offset: 0x20
Reset Value: 0x00000000
• BR: Baud Rate
The baud rate ( ) of the transmission, calculated using the following formula ( is the RC120M frequency):
BR should not be set to a value smaller than 32.
Writing a value to this field will update the baud rate of the transmission.
Reading this field will give the current baud rate of the transmission.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
BR[15:8]
76543210
BR[7:0]
f
br f
aw
f
br
8f
aw
BR = -----------
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ATUC64/128/256L3/4U
33.7.10 Version Register
Name: VERSION
Access Type: Read-only
Offset: 0x24
Reset Value: 0x00000200
• VERSION: Version Number
Version number of the module. No functionality associated.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
- - - - VERSION[11:8]
76543210
VERSION[7:0]
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33.7.11 Clock Request Register
Name: CLKR
Access Type: Read/Write
Offset: 0x28
Reset Value: 0x00000000
• CLKEN: Clock Enable
0: The aWire clock is disabled.
1: The aWire clock is enabled.
Writing a zero to this bit will disable the aWire clock.
Writing a one to this bit will enable the aWire clock.
31 30 29 28 27 26 25 24
--------
23 22 21 20 19 18 17 16
--------
15 14 13 12 11 10 9 8
--------
76543210
- - - - - - - CLKEN
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33.8 Module Configuration
The specific configuration for each aWire instance is listed in the following tables.The module
bus clocks listed here are connected to the system bus clocks. Please refer to the Power Manager
chapter for details.
Table 33-4. AW Clocks
Clock Name Description
CLK_AW Clock for the AW bus interface
Table 33-5. Register Reset Values
Register Reset Value
VERSION 0x00000230
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34. Programming and Debugging
34.1 Overview
The ATUC64/128/256L3/4U supports programming and debugging through two interfaces,
JTAG or aWire. JTAG is an industry standard interface and allows boundary scan for PCB testing,
as well as daisy-chaining of multiple devices on the PCB. aWire is an Atmel proprietary
protocol which offers higher throughput and robust communication, and does not require application
pins to be reserved. Either interface provides access to the internal Service Access Bus
(SAB), which offers a bridge to the High Speed Bus, giving access to memories and peripherals
in the device. By using this bridge to the bus system, the flash and fuses can thus be programmed
by accessing the Flash Controller in the same manner as the CPU.
The SAB also provides access to the Nexus-compliant On-chip Debug (OCD) system in the
device, which gives the user non-intrusive run-time control of the program execution. Additionally,
trace information can be output on the Auxiliary (AUX) debug port or buffered in internal
RAM for later retrieval by JTAG or aWire.
34.2 Service Access Bus
The AVR32 architecture offers a common interface for access to On-chip Debug, programming,
and test functions. These are mapped on a common bus called the Service Access Bus (SAB),
which is linked to the JTAG and aWire port through a bus master module, which also handles
synchronization between the debugger and SAB clocks.
When accessing the SAB through the debugger there are no limitations on debugger frequency
compared to chip frequency, although there must be an active system clock in order for the SAB
accesses to complete. If the system clock is switched off in sleep mode, activity on the debugger
will restart the system clock automatically, without waking the device from sleep. Debuggers
may optimize the transfer rate by adjusting the frequency in relation to the system clock. This
ratio can be measured with debug protocol specific instructions.
The Service Access Bus uses 36 address bits to address memory or registers in any of the
slaves on the bus. The bus supports sized accesses of bytes (8 bits), halfwords (16 bits), or
words (32 bits). All accesses must be aligned to the size of the access, i.e. halfword accesses
must have the lowest address bit cleared, and word accesses must have the two lowest address
bits cleared.
34.2.1 SAB Address Map
The SAB gives the user access to the internal address space and other features through a 36
bits address space. The 4 MSBs identify the slave number, while the 32 LSBs are decoded
within the slave’s address space. The SAB slaves are shown in Table 34-1.
Table 34-1. SAB Slaves, Addresses and Descriptions
Slave Address [35:32] Description
Unallocated 0x0 Intentionally unallocated
OCD 0x1 OCD registers
HSB 0x4 HSB memory space, as seen by the CPU
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34.2.2 SAB Security Restrictions
The Service Access bus can be restricted by internal security measures. A short description of
the security measures are found in the table below.
34.2.2.1 Security measure and control location
A security measure is a mechanism to either block or allow SAB access to a certain address or
address range. A security measure is enabled or disabled by one or several control signals. This
is called the control location for the security measure.
These security measures can be used to prevent an end user from reading out the code programmed
in the flash, for instance.
Below follows a more in depth description of what locations are accessible when the security
measures are active.
Note: 1. Second Word of the User Page, refer to the Fuses Settings section for details.
HSB 0x5 Alternative mapping for HSB space, for compatibility with
other 32-bit AVR devices.
Memory Service
Unit 0x6 Memory Service Unit registers
Reserved Other Unused
Table 34-1. SAB Slaves, Addresses and Descriptions
Slave Address [35:32] Description
Table 34-2. SAB Security Measures
Security Measure Control Location Description
Secure mode FLASHCDW
SECURE bits set
Allocates a portion of the flash for secure code. This code
cannot be read or debugged. The User page is also locked.
Security bit FLASHCDW
security bit set
Programming and debugging not possible, very restricted
access.
User code
programming
FLASHCDW
UPROT + security
bit set
Restricts all access except parts of the flash and the flash
controller for programming user code. Debugging is not
possible unless an OS running from the secure part of the
flash supports it.
Table 34-3. Secure Mode SAB Restrictions
Name Address Start Address End Access
Secure flash area 0x580000000 0x580000000 +
(USERPAGE[15:0] << 10) Blocked
Secure RAM area 0x500000000 0x500000000 +
(USERPAGE[31:16] << 10) Blocked
User page 0x580800000 0x581000000 Read
Other accesses - - As normal
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Table 34-4. Security Bit SAB Restrictions
Name Address start Address end Access
OCD DCCPU,
OCD DCEMU,
OCD DCSR
0x100000110 0x100000118 Read/Write
User page 0x580800000 0x581000000 Read
Other accesses - - Blocked
Table 34-5. User Code Programming SAB Restrictions
Name Address start Address end Access
OCD DCCPU,
OCD DCEMU,
OCD DCSR
0x100000110 0x100000118 Read/Write
User page 0x580800000 0x581000000 Read
FLASHCDW PB
interface 0x5FFFE0000 0x5FFFE0400 Read/Write
FLASH pages
outside
BOOTPROT
0x580000000 +
BOOTPROT size 0x580000000 + Flash size Read/Write
Other accesses - - Blocked
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34.3 On-Chip Debug
Rev: 2.1.2.0
34.3.1 Features
• Debug interface in compliance with IEEE-ISTO 5001-2003 (Nexus 2.0) Class 2+
• JTAG or aWire access to all on-chip debug functions
• Advanced Program, Data, Ownership, and Watchpoint trace supported
• NanoTrace aWire- or JTAG-based trace access
• Auxiliary port for high-speed trace information
• Hardware support for 6 Program and 2 Data breakpoints
• Unlimited number of software breakpoints supported
• Automatic CRC check of memory regions
34.3.2 Overview
Debugging on the ATUC64/128/256L3/4U is facilitated by a powerful On-Chip Debug (OCD)
system. The user accesses this through an external debug tool which connects to the JTAG or
aWire port and the Auxiliary (AUX) port if implemented. The AUX port is primarily used for trace
functions, and an aWire- or JTAG-based debugger is sufficient for basic debugging.
The debug system is based on the Nexus 2.0 standard, class 2+, which includes:
• Basic run-time control
• Program breakpoints
• Data breakpoints
• Program trace
• Ownership trace
• Data trace
In addition to the mandatory Nexus debug features, the ATUC64/128/256L3/4U implements
several useful OCD features, such as:
• Debug Communication Channel between CPU and debugger
• Run-time PC monitoring
• CRC checking
• NanoTrace
• Software Quality Assurance (SQA) support
The OCD features are controlled by OCD registers, which can be accessed by the debugger, for
instance when the NEXUS_ACCESS JTAG instruction is loaded. The CPU can also access
OCD registers directly using mtdr/mfdr instructions in any privileged mode. The OCD registers
are implemented based on the recommendations in the Nexus 2.0 standard, and are detailed in
the AVR32UC Technical Reference Manual.
34.3.3 I/O Lines Description
The OCD AUX trace port contains a number of pins, as shown in Table 34-6 on page 848.
These are multiplexed with I/O Controller lines, and must explicitly be enabled by writing OCD
registers before the debug session starts. The AUX port is mapped to two different locations,
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selectable by OCD Registers, minimizing the chance that the AUX port will need to be shared
with an application.
34.3.4 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
34.3.4.1 Power Management
The OCD clock operates independently of the CPU clock. If enabled in the Power Manager, the
OCD clock (CLK_OCD) will continue running even if the CPU enters a sleep mode that disables
the CPU clock.
34.3.4.2 Clocks
The OCD has a clock (CLK_OCD) running synchronously with the CPU clock. This clock is generated
by the Power Manager. The clock is enabled at reset, and can be disabled by writing to
the Power Manager.
34.3.4.3 Interrupt
The OCD system interrupt request lines are connected to the interrupt controller. Using the OCD
interrupts requires the interrupt controller to be programmed first.
Table 34-6. Auxiliary Port Signals
Pin Name Pin Description Direction Active Level Type
MCKO Trace data output clock Output Digital
MDO[5:0] Trace data output Output Digital
MSEO[1:0] Trace frame control Output Digital
EVTI_N Event In Input Low Digital
EVTO_N Event Out Output Low Digital
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34.3.5 Block Diagram
Figure 34-1. On-Chip Debug Block Diagram
34.3.6 SAB-based Debug Features
A debugger can control all OCD features by writing OCD registers over the SAB interface. Many
of these do not depend on output on the AUX port, allowing an aWire- or JTAG-based debugger
to be used.
A JTAG-based debugger should connect to the device through a standard 10-pin IDC connector
as described in the AVR32UC Technical Reference Manual.
An aWire-based debugger should connect to the device through the RESET_N pin.
On-Chip Debug
JTAG
Debug PC
Debug
Instruction
CPU
Breakpoints
Program
Trace Data Trace Ownership
Trace
Transmit Queue Watchpoints
AUX
JTAG
Internal
SRAM
Service Access Bus
Memory
Service
Unit
HSB Bus Matrix Memories and
peripherals
aWire
aWire
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Figure 34-2. JTAG-based Debugger
Figure 34-3. aWire-based Debugger
34.3.6.1 Debug Communication Channel
The Debug Communication Channel (DCC) consists of a pair OCD registers with associated
handshake logic, accessible to both CPU and debugger. The registers can be used to exchange
data between the CPU and the debugmaster, both runtime as well as in debug mode.
32-bit AVR
JTAG-based
debug tool
PC
JTAG
10-pin IDC
32-bit AVR
aWire-based
debug tool
PC
aWire
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The OCD system can generate an interrupt to the CPU when DCCPU is read and when DCEMU
is written. This enables the user to build a custum debug protocol using only these registers. The
DCCPU and DCEMU registers are available even when the security bit in the flash is active.
For more information refer to the AVR32UC Technical Reference Manual.
34.3.6.2 Breakpoints
One of the most fundamental debug features is the ability to halt the CPU, to examine registers
and the state of the system. This is accomplished by breakpoints, of which many types are
available:
• Unconditional breakpoints are set by writing OCD registers by the debugger, halting the CPU
immediately.
• Program breakpoints halt the CPU when a specific address in the program is executed.
• Data breakpoints halt the CPU when a specific memory address is read or written, allowing
variables to be watched.
• Software breakpoints halt the CPU when the breakpoint instruction is executed.
When a breakpoint triggers, the CPU enters debug mode, and the D bit in the status register is
set. This is a privileged mode with dedicated return address and return status registers. All privileged
instructions are permitted. Debug mode can be entered as either OCD Mode, running
instructions from the debugger, or Monitor Mode, running instructions from program memory.
34.3.6.3 OCD Mode
When a breakpoint triggers, the CPU enters OCD mode, and instructions are fetched from the
Debug Instruction OCD register. Each time this register is written by the debugger, the instruction
is executed, allowing the debugger to execute CPU instructions directly. The debug master
can e.g. read out the register file by issuing mtdr instructions to the CPU, writing each register to
the Debug Communication Channel OCD registers.
34.3.6.4 Monitor Mode
Since the OCD registers are directly accessible by the CPU, it is possible to build a softwarebased
debugger that runs on the CPU itself. Setting the Monitor Mode bit in the Development
Control register causes the CPU to enter Monitor Mode instead of OCD mode when a breakpoint
triggers. Monitor Mode is similar to OCD mode, except that instructions are fetched from the
debug exception vector in regular program memory, instead of issued by the debug master.
34.3.6.5 Program Counter Monitoring
Normally, the CPU would need to be halted for a debugger to examine the current PC value.
However, the ATUC64/128/256L3/4U also proves a Debug Program Counter OCD register,
where the debugger can continuously read the current PC without affecting the CPU. This allows
the debugger to generate a simple statistic of the time spent in various areas of the code, easing
code optimization.
34.3.7 Memory Service Unit
The Memory Service Unit (MSU) is a block dedicated to test and debug functionality. It is controlled
through a dedicated set of registers addressed through the Service Access Bus.
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34.3.7.1 Cyclic Redundancy Check (CRC)
The MSU can be used to automatically calculate the CRC of a block of data in memory. The
MSU will then read out each word in the specified memory block and report the CRC32-value in
an MSU register.
34.3.7.2 NanoTrace
The MSU additionally supports NanoTrace. This is a 32-bit AVR-specific feature, in which trace
data is output to memory instead of the AUX port. This allows the trace data to be extracted by
the debugger through the SAB, enabling trace features for aWire- or JTAG-based debuggers.
The user must write MSU registers to configure the address and size of the memory block to be
used for NanoTrace. The NanoTrace buffer can be anywhere in the physical address range,
including internal and external RAM, through an EBI, if present. This area may not be used by
the application running on the CPU.
34.3.8 AUX-based Debug Features
Utilizing the Auxiliary (AUX) port gives access to a wide range of advanced debug features. Of
prime importance are the trace features, which allow an external debugger to receive continuous
information on the program execution in the CPU. Additionally, Event In and Event Out pins
allow external events to be correlated with the program flow.
Debug tools utilizing the AUX port should connect to the device through a Nexus-compliant Mictor-38
connector, as described in the AVR32UC Technical Reference manual. This connector
includes the JTAG signals and the RESET_N pin, giving full access to the programming and
debug features in the device.
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Figure 34-4. AUX+JTAG Based Debugger
34.3.8.1 Trace Operation
Trace features are enabled by writing OCD registers by the debugger. The OCD extracts the
trace information from the CPU, compresses this information and formats it into variable-length
messages according to the Nexus standard. The messages are buffered in a 16-frame transmit
queue, and are output on the AUX port one frame at a time.
The trace features can be configured to be very selective, to reduce the bandwidth on the AUX
port. In case the transmit queue overflows, error messages are produced to indicate loss of
data. The transmit queue module can optionally be configured to halt the CPU when an overflow
occurs, to prevent the loss of messages, at the expense of longer run-time for the program.
34.3.8.2 Program Trace
Program trace allows the debugger to continuously monitor the program execution in the CPU.
Program trace messages are generated for every branch in the program, and contains compressed
information, which allows the debugger to correlate the message with the source code
to identify the branch instruction and target address.
34.3.8.3 Data Trace
Data trace outputs a message every time a specific location is read or written. The message
contains information about the type (read/write) and size of the access, as well as the address
and data of the accessed location. The ATUC64/128/256L3/4U contains two data trace chanAVR32
AUX+JTAG
debu g tool
JTAG AUX
h ig h s p e e d
M ic to r3 8
T ra ce b u ffe r
P C
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nels, each of which are controlled by a pair of OCD registers which determine the range of
addresses (or single address) which should produce data trace messages.
34.3.8.4 Ownership Trace
Program and data trace operate on virtual addresses. In cases where an operating system runs
several processes in overlapping virtual memory segments, the Ownership Trace feature can be
used to identify the process switch. When the O/S activates a process, it will write the process ID
number to an OCD register, which produces an Ownership Trace Message, allowing the debugger
to switch context for the subsequent program and data trace messages. As the use of this
feature depends on the software running on the CPU, it can also be used to extract other types
of information from the system.
34.3.8.5 Watchpoint Messages
The breakpoint modules normally used to generate program and data breakpoints can also be
used to generate Watchpoint messages, allowing a debugger to monitor program and data
events without halting the CPU. Watchpoints can be enabled independently of breakpoints, so a
breakpoint module can optionally halt the CPU when the trigger condition occurs. Data trace
modules can also be configured to produce watchpoint messages instead of regular data trace
messages.
34.3.8.6 Event In and Event Out Pins
The AUX port also contains an Event In pin (EVTI_N) and an Event Out pin (EVTO_N). EVTI_N
can be used to trigger a breakpoint when an external event occurs. It can also be used to trigger
specific program and data trace synchronization messages, allowing an external event to be
correlated to the program flow.
When the CPU enters debug mode, a Debug Status message is transmitted on the trace port.
All trace messages can be timestamped when they are received by the debug tool. However,
due to the latency of the transmit queue buffering, the timestamp will not be 100% accurate. To
improve this, EVTO_N can toggle every time a message is inserted into the transmit queue,
allowing trace messages to be timestamped precisely. EVTO_N can also toggle when a breakpoint
module triggers, or when the CPU enters debug mode, for any reason. This can be used to
measure precisely when the respective internal event occurs.
34.3.8.7 Software Quality Analysis (SQA)
Software Quality Analysis (SQA) deals with two important issues regarding embedded software
development. Code coverage involves identifying untested parts of the embedded code, to
improve test procedures and thus the quality of the released software. Performance analysis
allows the developer to precisely quantify the time spent in various parts of the code, allowing
bottlenecks to be identified and optimized.
Program trace must be used to accomplish these tasks without instrumenting (altering) the code
to be examined. However, traditional program trace cannot reconstruct the current PC value
without correlating the trace information with the source code, which cannot be done on-the-fly.
This limits program trace to a relatively short time segment, determined by the size of the trace
buffer in the debug tool.
The OCD system in ATUC64/128/256L3/4U extends program trace with SQA capabilities, allowing
the debug tool to reconstruct the PC value on-the-fly. Code coverage and performance
analysis can thus be reported for an unlimited execution sequence.
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34.4 JTAG and Boundary-scan (JTAG)
Rev: 2.2.2.4
34.4.1 Features
• IEEE1149.1 compliant JTAG Interface
• Boundary-scan Chain for board-level testing
• Direct memory access and programming capabilities through JTAG Interface
34.4.2 Overview
The JTAG Interface offers a four pin programming and debug solution, including boundary-scan
support for board-level testing.
Figure 34-5 on page 856 shows how the JTAG is connected in an 32-bit AVR device. The TAP
Controller is a state machine controlled by the TCK and TMS signals. The TAP Controller
selects either the JTAG Instruction Register or one of several Data Registers as the scan chain
(shift register) between the TDI-input and TDO-output.
The Instruction Register holds JTAG instructions controlling the behavior of a Data Register. The
Device Identification Register, Bypass Register, and the boundary-scan chain are the Data Registers
used for board-level testing. The Reset Register can be used to keep the device reset
during test or programming.
The Service Access Bus (SAB) interface contains address and data registers for the Service
Access Bus, which gives access to On-Chip Debug, programming, and other functions in the
device. The SAB offers several modes of access to the address and data registers, as described
in Section 34.4.11.
Section 34.5 lists the supported JTAG instructions, with references to the description in this
document.
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34.4.3 Block Diagram
Figure 34-5. JTAG and Boundary-scan Access
34.4.4 I/O Lines Description
34.4.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
Table 34-7. I/O Line Description
Pin Name Pin Description Type Active Level
RESET_N External reset pin. Used when enabling and disabling the JTAG. Input Low
TCK Test Clock Input. Fully asynchronous to system clock frequency. Input
TMS Test Mode Select, sampled on rising TCK. Input
TDI Test Data In, sampled on rising TCK. Input
TDO Test Data Out, driven on falling TCK. Output
32-bit AVR device
JTAG data registers
TAP
Controller
Instruction Register
Device Identification
Register
By-pass Register
Reset Register
Service Access Bus
interface
Boundary Scan Chain
Pins and analog blocks
Data register
scan enable
JTAG Pins
Boundary scan enable
2nd JTAG
device
JTAG master
TDO TDI
Part specific registers
...
TMS TDO TDI
TMS
TCK
TCK
Instruction register
scan enable
SAB Internal I/O
lines
JTAG
TMS
TDI
TDO
TCK
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34.4.5.1 I/O Lines
The TMS, TDI, TDO, and TCK pins are multiplexed with I/O lines. When the JTAG is used the
associated pins must be enabled. To enable the JTAG pins, refer to Section 34.4.7.
While using the multiplexed JTAG lines all normal peripheral activity on these lines is disabled.
The user must make sure that no external peripheral is blocking the JTAG lines while
debugging.
34.4.5.2 Power Management
When an instruction that accesses the SAB is loaded in the instruction register, before entering
a sleep mode, the system clocks are not switched off to allow debugging in sleep modes. This
can lead to a program behaving differently when debugging.
34.4.5.3 Clocks
The JTAG Interface uses the external TCK pin as clock source. This clock must be provided by
the JTAG master.
Instructions that use the SAB bus requires the internal main clock to be running.
34.4.6 JTAG Interface
The JTAG Interface is accessed through the dedicated JTAG pins shown in Table 34-7 on page
856. The TMS control line navigates the TAP controller, as shown in Figure 34-6 on page 858.
The TAP controller manages the serial access to the JTAG Instruction and Data registers. Data
is scanned into the selected instruction or data register on TDI, and out of the register on TDO,
in the Shift-IR and Shift-DR states, respectively. The LSB is shifted in and out first. TDO is highZ
in other states than Shift-IR and Shift-DR.
The device implements a 5-bit Instruction Register (IR). A number of public JTAG instructions
defined by the JTAG standard are supported, as described in Section 34.5.2, as well as a number
of 32-bit AVR-specific private JTAG instructions described in Section 34.5.3. Each
instruction selects a specific data register for the Shift-DR path, as described for each
instruction.
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Figure 34-6. TAP Controller State Diagram
Test-LogicReset
Run-Test/
Idle
Select-DR
Scan
Select-IR
Scan
Capture-DR Capture-IR
Shift-DR Shift-IR
Exit1-DR Exit1-IR
Pause-DR Pause-IR
Exit2-DR Exit2-IR
Update-DR Update-IR
0
1 1
1
0
0
1
0
1
1
0
0
1
0
1
1
1
0
1 1
0 0
1 1
0
1
0
0 0
0
0
1
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34.4.7 How to Initialize the Module
To enable the JTAG pins the TCK pin must be held low while the RESET_N pin is released.
After enabling the JTAG interface the halt bit is set automatically to prevent the system from running
code after the interface is enabled. To make the CPU run again set halt to zero using the
HALT command..
JTAG operation when RESET_N is pulled low is not possible.
Independent of the initial state of the TAP Controller, the Test-Logic-Reset state can always be
entered by holding TMS high for 5 TCK clock periods. This sequence should always be applied
at the start of a JTAG session and after enabling the JTAG pins to bring the TAP Controller into
a defined state before applying JTAG commands. Applying a 0 on TMS for 1 TCK period brings
the TAP Controller to the Run-Test/Idle state, which is the starting point for JTAG operations.
34.4.8 How to disable the module
To disable the JTAG pins the TCK pin must be held high while RESET_N pin is released.
34.4.9 Typical Sequence
Assuming Run-Test/Idle is the present state, a typical scenario for using the JTAG Interface
follows.
34.4.9.1 Scanning in JTAG Instruction
At the TMS input, apply the sequence 1, 1, 0, 0 at the rising edges of TCK to enter the Shift
Instruction Register (Shift-IR) state. While in this state, shift the 5 bits of the JTAG instructions
into the JTAG instruction register from the TDI input at the rising edge of TCK. During shifting,
the JTAG outputs status bits on TDO, refer to Section 34.5 for a description of these. The TMS
input must be held low during input of the 4 LSBs in order to remain in the Shift-IR state. The
JTAG Instruction selects a particular Data Register as path between TDI and TDO and controls
the circuitry surrounding the selected Data Register.
Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. The instruction is latched
onto the parallel output from the shift register path in the Update-IR state. The Exit-IR, Pause-IR,
and Exit2-IR states are only used for navigating the state machine.
Figure 34-7. Scanning in JTAG Instruction
34.4.9.2 Scanning in/out Data
At the TMS input, apply the sequence 1, 0, 0 at the rising edges of TCK to enter the Shift Data
Register (Shift-DR) state. While in this state, upload the selected Data Register (selected by the
present JTAG instruction in the JTAG Instruction Register) from the TDI input at the rising edge
TCK
TAP State TLR RTI SelDR SelIR CapIR ShIR Ex1IR UpdIR RTI
TMS
TDI Instruction
TDO ImplDefined
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of TCK. In order to remain in the Shift-DR state, the TMS input must be held low. While the Data
Register is shifted in from the TDI pin, the parallel inputs to the Data Register captured in the
Capture-DR state is shifted out on the TDO pin.
Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. If the selected Data Register
has a latched parallel-output, the latching takes place in the Update-DR state. The Exit-DR,
Pause-DR, and Exit2-DR states are only used for navigating the state machine.
As shown in the state diagram, the Run-Test/Idle state need not be entered between selecting
JTAG instruction and using Data Registers.
34.4.10 Boundary-scan
The boundary-scan chain has the capability of driving and observing the logic levels on the digital
I/O pins, as well as the boundary between digital and analog logic for analog circuitry having
off-chip connections. At system level, all ICs having JTAG capabilities are connected serially by
the TDI/TDO signals to form a long shift register. An external controller sets up the devices to
drive values at their output pins, and observe the input values received from other devices. The
controller compares the received data with the expected result. In this way, boundary-scan provides
a mechanism for testing interconnections and integrity of components on Printed Circuits
Boards by using the 4 TAP signals only.
The four IEEE 1149.1 defined mandatory JTAG instructions IDCODE, BYPASS, SAMPLE/PRELOAD,
and EXTEST can be used for testing the Printed Circuit Board. Initial scanning of the
data register path will show the ID-code of the device, since IDCODE is the default JTAG
instruction. It may be desirable to have the 32-bit AVR device in reset during test mode. If not
reset, inputs to the device may be determined by the scan operations, and the internal software
may be in an undetermined state when exiting the test mode. If needed, the BYPASS instruction
can be issued to make the shortest possible scan chain through the device. The device can be
set in the reset state either by pulling the external RESETn pin low, or issuing the AVR_RESET
instruction with appropriate setting of the Reset Data Register.
The EXTEST instruction is used for sampling external pins and loading output pins with data.
The data from the output latch will be driven out on the pins as soon as the EXTEST instruction
is loaded into the JTAG IR-register. Therefore, the SAMPLE/PRELOAD should also be used for
setting initial values to the scan ring, to avoid damaging the board when issuing the EXTEST
instruction for the first time. SAMPLE/PRELOAD can also be used for taking a snapshot of the
external pins during normal operation of the part.
When using the JTAG Interface for boundary-scan, the JTAG TCK clock is independent of the
internal chip clock. The internal chip clock is not required to run during boundary-scan
operations.
NOTE: For pins connected to 5V lines care should be taken to not drive the pins to a logic one
using boundary-scan, as this will create a current flowing from the 3,3V driver to the 5V pull-up
on the line. Optionally a series resistor can be added between the line and the pin to reduce the
current.
Details about the boundary-scan chain can be found in the BSDL file for the device. This can be
found on the Atmel website.
34.4.11 Service Access Bus
The AVR32 architecture offers a common interface for access to On-Chip Debug, programming,
and test functions. These are mapped on a common bus called the Service Access Bus (SAB),
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which is linked to the JTAG through a bus master module, which also handles synchronization
between the TCK and SAB clocks.
For more information about the SAB and a list of SAB slaves see the Service Access Bus
chapter.
34.4.11.1 SAB Address Mode
The MEMORY_SIZED_ACCESS instruction allows a sized read or write to any 36-bit address
on the bus. MEMORY_WORD_ACCESS is a shorthand instruction for 32-bit accesses to any
36-bit address, while the NEXUS_ACCESS instruction is a Nexus-compliant shorthand instruction
for accessing the 32-bit OCD registers in the 7-bit address space reserved for these. These
instructions require two passes through the Shift-DR TAP state: one for the address and control
information, and one for data.
34.4.11.2 Block Transfer
To increase the transfer rate, consecutive memory accesses can be accomplished by the
MEMORY_BLOCK_ACCESS instruction, which only requires a single pass through Shift-DR for
data transfer only. The address is automatically incremented according to the size of the last
SAB transfer.
34.4.11.3 Canceling a SAB Access
It is possible to abort an ongoing SAB access by the CANCEL_ACCESS instruction, to avoid
hanging the bus due to an extremely slow slave.
34.4.11.4 Busy Reporting
As the time taken to perform an access may vary depending on system activity and current chip
frequency, all the SAB access JTAG instructions can return a busy indicator. This indicates
whether a delay needs to be inserted, or an operation needs to be repeated in order to be successful.
If a new access is requested while the SAB is busy, the request is ignored.
The SAB becomes busy when:
• Entering Update-DR in the address phase of any read operation, e.g., after scanning in a
NEXUS_ACCESS address with the read bit set.
• Entering Update-DR in the data phase of any write operation, e.g., after scanning in data for
a NEXUS_ACCESS write.
• Entering Update-DR during a MEMORY_BLOCK_ACCESS.
• Entering Update-DR after scanning in a counter value for SYNC.
• Entering Update-IR after scanning in a MEMORY_BLOCK_ACCESS if the previous access
was a read and data was scanned after scanning the address.
The SAB becomes ready again when:
• A read or write operation completes.
• A SYNC countdown completed.
• A operation is cancelled by the CANCEL_ACCESS instruction.
What to do if the busy bit is set:
• During Shift-IR: The new instruction is selected, but the previous operation has not yet
completed and will continue (unless the new instruction is CANCEL_ACCESS). You may
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continue shifting the same instruction until the busy bit clears, or start shifting data. If shifting
data, you must be prepared that the data shift may also report busy.
• During Shift-DR of an address: The new address is ignored. The SAB stays in address mode,
so no data must be shifted. Repeat the address until the busy bit clears.
• During Shift-DR of read data: The read data is invalid. The SAB stays in data mode. Repeat
scanning until the busy bit clears.
• During Shift-DR of write data: The write data is ignored. The SAB stays in data mode. Repeat
scanning until the busy bit clears.
34.4.11.5 Error Reporting
The Service Access Bus may not be able to complete all accesses as requested. This may be
because the address is invalid, the addressed area is read-only or cannot handle byte/halfword
accesses, or because the chip is set in a protected mode where only limited accesses are
allowed.
The error bit is updated when an access completes, and is cleared when a new access starts.
What to do if the error bit is set:
• During Shift-IR: The new instruction is selected. The last operation performed using the old
instruction did not complete successfully.
• During Shift-DR of an address: The previous operation failed. The new address is accepted.
If the read bit is set, a read operation is started.
• During Shift-DR of read data: The read operation failed, and the read data is invalid.
• During Shift-DR of write data: The previous write operation failed. The new data is accepted
and a write operation started. This should only occur during block writes or stream writes. No
error can occur between scanning a write address and the following write data.
• While polling with CANCEL_ACCESS: The previous access was cancelled. It may or may not
have actually completed.
• After power-up: The error bit is set after power up, but there has been no previous SAB
instruction so this error can be discarded.
34.4.11.6 Protected Reporting
A protected status may be reported during Shift-IR or Shift-DR. This indicates that the security
bit in the Flash Controller is set and that the chip is locked for access, according to Section
34.5.1.
The protected state is reported when:
• The Flash Controller is under reset. This can be due to the AVR_RESET command or the
RESET_N line.
• The Flash Controller has not read the security bit from the flash yet (This will take a a few
ms). Happens after the Flash Controller reset has been released.
• The security bit in the Flash Controller is set.
What to do if the protected bit is set:
• Release all active AVR_RESET domains, if any.
• Release the RESET_N line.
• Wait a few ms for the security bit to clear. It can be set temporarily due to a reset.
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• Perform a CHIP_ERASE to clear the security bit. NOTE: This will erase all the contents of the
non-volatile memory.
34.5 JTAG Instruction Summary
The implemented JTAG instructions in the 32-bit AVR are shown in the table below.
34.5.1 Security Restrictions
When the security fuse in the Flash is programmed, the following JTAG instructions are
restricted:
• NEXUS_ACCESS
• MEMORY_WORD_ACCESS
• MEMORY_BLOCK_ACCESS
• MEMORY_SIZED_ACCESS
For description of what memory locations remain accessible, please refer to the SAB address
map.
Full access to these instructions is re-enabled when the security fuse is erased by the
CHIP_ERASE JTAG instruction.
Table 34-8. JTAG Instruction Summary
Instruction
OPCODE Instruction Description
0x01 IDCODE Select the 32-bit Device Identification register as data register.
0x02 SAMPLE_PRELOAD Take a snapshot of external pin values without affecting system operation.
0x03 EXTEST Select boundary-scan chain as data register for testing circuitry external to
the device.
0x04 INTEST Select boundary-scan chain for internal testing of the device.
0x06 CLAMP Bypass device through Bypass register, while driving outputs from boundaryscan
register.
0x0C AVR_RESET Apply or remove a static reset to the device
0x0F CHIP_ERASE Erase the device
0x10 NEXUS_ACCESS Select the SAB Address and Data registers as data register for the TAP. The
registers are accessed in Nexus mode.
0x11 MEMORY_WORD_ACCESS Select the SAB Address and Data registers as data register for the TAP.
0x12 MEMORY_BLOCK_ACCESS Select the SAB Data register as data register for the TAP. The address is
auto-incremented.
0x13 CANCEL_ACCESS Cancel an ongoing Nexus or Memory access.
0x14 MEMORY_SERVICE Select the SAB Address and Data registers as data register for the TAP. The
registers are accessed in Memory Service mode.
0x15 MEMORY_SIZED_ACCESS Select the SAB Address and Data registers as data register for the TAP.
0x17 SYNC Synchronization counter
0x1C HALT Halt the CPU for safe programming.
0x1F BYPASS Bypass this device through the bypass register.
Others N/A Acts as BYPASS
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Note that the security bit will read as programmed and block these instructions also if the Flash
Controller is statically reset.
Other security mechanisms can also restrict these functions. If such mechanisms are present
they are listed in the SAB address map section.
34.5.1.1 Notation
Table 34-10 on page 864 shows bit patterns to be shifted in a format like "peb01". Each character
corresponds to one bit, and eight bits are grouped together for readability. The least
significantbit is always shifted first, and the most significant bit shifted last. The symbols used
are shown in Table 34-9.
In many cases, it is not required to shift all bits through the data register. Bit patterns are shown
using the full width of the shift register, but the suggested or required bits are emphasized using
bold text. I.e. given the pattern "aaaaaaar xxxxxxxx xxxxxxxx xxxxxxxx xx", the shift register is
34 bits, but the test or debug unit may choose to shift only 8 bits "aaaaaaar".
The following describes how to interpret the fields in the instruction description tables:
Table 34-9. Symbol Description
Symbol Description
0 Constant low value - always reads as zero.
1 Constant high value - always reads as one.
a An address bit - always scanned with the least significant bit first
b A busy bit. Reads as one if the SAB was busy, or zero if it was not. See Section 34.4.11.4 for
details on how the busy reporting works.
d A data bit - always scanned with the least significant bit first.
e An error bit. Reads as one if an error occurred, or zero if not. See Section 34.4.11.5 for
details on how the error reporting works.
p
The chip protected bit. Some devices may be set in a protected state where access to chip
internals are severely restricted. See the documentation for the specific device for details.
On devices without this possibility, this bit always reads as zero.
r A direction bit. Set to one to request a read, set to zero to request a write.
s A size bit. The size encoding is described where used.
x A don’t care bit. Any value can be shifted in, and output data should be ignored.
Table 34-10. Instruction Description
Instruction Description
IR input value
Shows the bit pattern to shift into IR in the Shift-IR state in order to select this
instruction. The pattern is show both in binary and in hexadecimal form for
convenience.
Example: 10000 (0x10)
IR output value
Shows the bit pattern shifted out of IR in the Shift-IR state when this instruction is
active.
Example: peb01
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34.5.2 Public JTAG Instructions
The JTAG standard defines a number of public JTAG instructions. These instructions are
described in the sections below.
34.5.2.1 IDCODE
This instruction selects the 32 bit Device Identification register (DID) as Data Register. The DID
register consists of a version number, a device number, and the manufacturer code chosen by
JEDEC. This is the default instruction after a JTAG reset. Details about the DID register can be
found in the module configuration section at the end of this chapter.
Starting in Run-Test/Idle, the Device Identification register is accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Capture-DR: The IDCODE value is latched into the shift register.
7. In Shift-DR: The IDCODE scan chain is shifted by the TCK input.
8. Return to Run-Test/Idle.
34.5.2.2 SAMPLE_PRELOAD
This instruction takes a snap-shot of the input/output pins without affecting the system operation,
and pre-loading the scan chain without updating the DR-latch. The boundary-scan chain is
selected as Data Register.
Starting in Run-Test/Idle, the Device Identification register is accessed in the following way:
DR Size Shows the number of bits in the data register chain when this instruction is active.
Example: 34 bits
DR input value
Shows which bit pattern to shift into the data register in the Shift-DR state when this
instruction is active. Multiple such lines may exist, e.g., to distinguish between
reads and writes.
Example: aaaaaaar xxxxxxxx xxxxxxxx xxxxxxxx xx
DR output value
Shows the bit pattern shifted out of the data register in the Shift-DR state when this
instruction is active. Multiple such lines may exist, e.g., to distinguish between
reads and writes.
Example: xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
Table 34-10. Instruction Description (Continued)
Instruction Description
Table 34-11. IDCODE Details
Instructions Details
IR input value 00001 (0x01)
IR output value p0001
DR Size 32
DR input value xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx
DR output value Device Identification Register
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1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Capture-DR: The Data on the external pins are sampled into the boundary-scan
chain.
7. In Shift-DR: The boundary-scan chain is shifted by the TCK input.
8. Return to Run-Test/Idle.
34.5.2.3 EXTEST
This instruction selects the boundary-scan chain as Data Register for testing circuitry external to
the 32-bit AVR package. The contents of the latched outputs of the boundary-scan chain is
driven out as soon as the JTAG IR-register is loaded with the EXTEST instruction.
Starting in Run-Test/Idle, the EXTEST instruction is accessed the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. In Update-IR: The data from the boundary-scan chain is applied to the output pins.
5. Return to Run-Test/Idle.
6. Select the DR Scan path.
7. In Capture-DR: The data on the external pins is sampled into the boundary-scan chain.
8. In Shift-DR: The boundary-scan chain is shifted by the TCK input.
9. In Update-DR: The data from the scan chain is applied to the output pins.
10. Return to Run-Test/Idle.
Table 34-12. SAMPLE_PRELOAD Details
Instructions Details
IR input value 00010 (0x02)
IR output value p0001
DR Size Depending on boundary-scan chain, see BSDL-file.
DR input value Depending on boundary-scan chain, see BSDL-file.
DR output value Depending on boundary-scan chain, see BSDL-file.
Table 34-13. EXTEST Details
Instructions Details
IR input value 00011 (0x03)
IR output value p0001
DR Size Depending on boundary-scan chain, see BSDL-file.
DR input value Depending on boundary-scan chain, see BSDL-file.
DR output value Depending on boundary-scan chain, see BSDL-file.
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34.5.2.4 INTEST
This instruction selects the boundary-scan chain as Data Register for testing internal logic in the
device. The logic inputs are determined by the boundary-scan chain, and the logic outputs are
captured by the boundary-scan chain. The device output pins are driven from the boundary-scan
chain.
Starting in Run-Test/Idle, the INTEST instruction is accessed the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. In Update-IR: The data from the boundary-scan chain is applied to the internal logic
inputs.
5. Return to Run-Test/Idle.
6. Select the DR Scan path.
7. In Capture-DR: The data on the internal logic is sampled into the boundary-scan chain.
8. In Shift-DR: The boundary-scan chain is shifted by the TCK input.
9. In Update-DR: The data from the boundary-scan chain is applied to internal logic
inputs.
10. Return to Run-Test/Idle.
34.5.2.5 CLAMP
This instruction selects the Bypass register as Data Register. The device output pins are driven
from the boundary-scan chain.
Starting in Run-Test/Idle, the CLAMP instruction is accessed the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. In Update-IR: The data from the boundary-scan chain is applied to the output pins.
5. Return to Run-Test/Idle.
6. Select the DR Scan path.
7. In Capture-DR: A logic ‘0’ is loaded into the Bypass Register.
8. In Shift-DR: Data is scanned from TDI to TDO through the Bypass register.
Table 34-14. INTEST Details
Instructions Details
IR input value 00100 (0x04)
IR output value p0001
DR Size Depending on boundary-scan chain, see BSDL-file.
DR input value Depending on boundary-scan chain, see BSDL-file.
DR output value Depending on boundary-scan chain, see BSDL-file.
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9. Return to Run-Test/Idle.
34.5.2.6 BYPASS
This instruction selects the 1-bit Bypass Register as Data Register.
Starting in Run-Test/Idle, the CLAMP instruction is accessed the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Capture-DR: A logic ‘0’ is loaded into the Bypass Register.
7. In Shift-DR: Data is scanned from TDI to TDO through the Bypass register.
8. Return to Run-Test/Idle.
34.5.3 Private JTAG Instructions
The 32-bit AVR defines a number of private JTAG instructions, not defined by the JTAG standard.
Each instruction is briefly described in text, with details following in table form.
34.5.3.1 NEXUS_ACCESS
This instruction allows Nexus-compliant access to the On-Chip Debug registers through the
SAB. The 7-bit register index, a read/write control bit, and the 32-bit data is accessed through
the JTAG port.
The data register is alternately interpreted by the SAB as an address register and a data register.
The SAB starts in address mode after the NEXUS_ACCESS instruction is selected, and
toggles between address and data mode each time a data scan completes with the busy bit
cleared.
NOTE: The polarity of the direction bit is inverse of the Nexus standard.
Table 34-15. CLAMP Details
Instructions Details
IR input value 00110 (0x06)
IR output value p0001
DR Size 1
DR input value x
DR output value x
Table 34-16. BYPASS Details
Instructions Details
IR input value 11111 (0x1F)
IR output value p0001
DR Size 1
DR input value x
DR output value x
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Starting in Run-Test/Idle, OCD registers are accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Shift-DR: Scan in the direction bit (1=read, 0=write) and the 7-bit address for the
OCD register.
7. Go to Update-DR and re-enter Select-DR Scan.
8. In Shift-DR: For a read operation, scan out the contents of the addressed register. For a
write operation, scan in the new contents of the register.
9. Return to Run-Test/Idle.
For any operation, the full 7 bits of the address must be provided. For write operations, 32 data
bits must be provided, or the result will be undefined. For read operations, shifting may be terminated
once the required number of bits have been acquired.
34.5.3.2 MEMORY_SERVICE
This instruction allows access to registers in an optional Memory Service Unit. The 7-bit register
index, a read/write control bit, and the 32-bit data is accessed through the JTAG port.
The data register is alternately interpreted by the SAB as an address register and a data register.
The SAB starts in address mode after the MEMORY_SERVICE instruction is selected, and
toggles between address and data mode each time a data scan completes with the busy bit
cleared.
Starting in Run-Test/Idle, Memory Service registers are accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Shift-DR: Scan in the direction bit (1=read, 0=write) and the 7-bit address for the
Memory Service register.
Table 34-17. NEXUS_ACCESS Details
Instructions Details
IR input value 10000 (0x10)
IR output value peb01
DR Size 34 bits
DR input value (Address phase) aaaaaaar xxxxxxxx xxxxxxxx xxxxxxxx xx
DR input value (Data read phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xx
DR input value (Data write phase) dddddddd dddddddd dddddddd dddddddd xx
DR output value (Address phase) xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
DR output value (Data read phase) eb dddddddd dddddddd dddddddd dddddddd
DR output value (Data write phase) xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
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7. Go to Update-DR and re-enter Select-DR Scan.
8. In Shift-DR: For a read operation, scan out the contents of the addressed register. For a
write operation, scan in the new contents of the register.
9. Return to Run-Test/Idle.
For any operation, the full 7 bits of the address must be provided. For write operations, 32 data
bits must be provided, or the result will be undefined. For read operations, shifting may be terminated
once the required number of bits have been acquired.
34.5.3.3 MEMORY_SIZED_ACCESS
This instruction allows access to the entire Service Access Bus data area. Data is accessed
through a 36-bit byte index, a 2-bit size, a direction bit, and 8, 16, or 32 bits of data. Not all units
mapped on the SAB bus may support all sizes of accesses, e.g., some may only support word
accesses.
The data register is alternately interpreted by the SAB as an address register and a data register.
The SAB starts in address mode after the MEMORY_SIZED_ACCESS instruction is
selected, and toggles between address and data mode each time a data scan completes with
the busy bit cleared.
Table 34-18. MEMORY_SERVICE Details
Instructions Details
IR input value 10100 (0x14)
IR output value peb01
DR Size 34 bits
DR input value (Address phase) aaaaaaar xxxxxxxx xxxxxxxx xxxxxxxx xx
DR input value (Data read phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xx
DR input value (Data write phase) dddddddd dddddddd dddddddd dddddddd xx
DR output value (Address phase) xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
DR output value (Data read phase) eb dddddddd dddddddd dddddddd dddddddd
DR output value (Data write phase) xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
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The size field is encoded as i Table 34-19.
Starting in Run-Test/Idle, SAB data is accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Shift-DR: Scan in the direction bit (1=read, 0=write), 2-bit access size, and the 36-bit
address of the data to access.
7. Go to Update-DR and re-enter Select-DR Scan.
8. In Shift-DR: For a read operation, scan out the contents of the addressed area. For a
write operation, scan in the new contents of the area.
9. Return to Run-Test/Idle.
For any operation, the full 36 bits of the address must be provided. For write operations, 32 data
bits must be provided, or the result will be undefined. For read operations, shifting may be terminated
once the required number of bits have been acquired.
Table 34-19. Size Field Semantics
Size field value Access size Data alignment
00 Byte (8 bits)
Address modulo 4 : data alignment
0: dddddddd xxxxxxxx xxxxxxxx xxxxxxxx
1: xxxxxxxx dddddddd xxxxxxxx xxxxxxxx
2: xxxxxxxx xxxxxxxx dddddddd xxxxxxxx
3: xxxxxxxx xxxxxxxx xxxxxxxx dddddddd
01 Halfword (16 bits)
Address modulo 4 : data alignment
0: dddddddd dddddddd xxxxxxxx xxxxxxxx
1: Not allowed
2: xxxxxxxx xxxxxxxx dddddddd dddddddd
3: Not allowed
10 Word (32 bits)
Address modulo 4 : data alignment
0: dddddddd dddddddd dddddddd dddddddd
1: Not allowed
2: Not allowed
3: Not allowed
11 Reserved N/A
Table 34-20. MEMORY_SIZED_ACCESS Details
Instructions Details
IR input value 10101 (0x15)
IR output value peb01
DR Size 39 bits
DR input value (Address phase) aaaaaaaa aaaaaaaa aaaaaaaa aaaaaaaa aaaassr
DR input value (Data read phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxx
DR input value (Data write phase) dddddddd dddddddd dddddddd dddddddd xxxxxxx
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34.5.3.4 MEMORY_WORD_ACCESS
This instruction allows access to the entire Service Access Bus data area. Data is accessed
through the 34 MSB of the SAB address, a direction bit, and 32 bits of data. This instruction is
identical to MEMORY_SIZED_ACCESS except that it always does word sized accesses. The
size field is implied, and the two lowest address bits are removed and not scanned in.
Note: This instruction was previously known as MEMORY_ACCESS, and is provided for backwards
compatibility.
The data register is alternately interpreted by the SAB as an address register and a data register.
The SAB starts in address mode after the MEMORY_WORD_ACCESS instruction is
selected, and toggles between address and data mode each time a data scan completes with
the busy bit cleared.
Starting in Run-Test/Idle, SAB data is accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Shift-DR: Scan in the direction bit (1=read, 0=write) and the 34-bit address of the
data to access.
7. Go to Update-DR and re-enter Select-DR Scan.
8. In Shift-DR: For a read operation, scan out the contents of the addressed area. For a
write operation, scan in the new contents of the area.
9. Return to Run-Test/Idle.
For any operation, the full 34 bits of the address must be provided. For write operations, 32 data
bits must be provided, or the result will be undefined. For read operations, shifting may be terminated
once the required number of bits have been acquired.
DR output value (Address phase) xxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
DR output value (Data read phase) xxxxxeb dddddddd dddddddd dddddddd dddddddd
DR output value (Data write phase) xxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
Table 34-20. MEMORY_SIZED_ACCESS Details (Continued)
Instructions Details
Table 34-21. MEMORY_WORD_ACCESS Details
Instructions Details
IR input value 10001 (0x11)
IR output value peb01
DR Size 35 bits
DR input value (Address phase) aaaaaaaa aaaaaaaa aaaaaaaa aaaaaaaa aar
DR input value (Data read phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xxx
DR input value (Data write phase) dddddddd dddddddd dddddddd dddddddd xxx
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34.5.3.5 MEMORY_BLOCK_ACCESS
This instruction allows access to the entire SAB data area. Up to 32 bits of data is accessed at a
time, while the address is sequentially incremented from the previously used address.
In this mode, the SAB address, size, and access direction is not provided with each access.
Instead, the previous address is auto-incremented depending on the specified size and the previous
operation repeated. The address must be set up in advance with
MEMORY_SIZE_ACCESS or MEMORY_WORD_ACCESS. It is allowed, but not required, to
shift data after shifting the address.
This instruction is primarily intended to speed up large quantities of sequential word accesses. It
is possible to use it also for byte and halfword accesses, but the overhead in this is case much
larger as 32 bits must still be shifted for each access.
The following sequence should be used:
1. Use the MEMORY_SIZE_ACCESS or MEMORY_WORD_ACCESS to read or write the
first location.
2. Return to Run-Test/Idle.
3. Select the IR Scan path.
4. In Capture-IR: The IR output value is latched into the shift register.
5. In Shift-IR: The instruction register is shifted by the TCK input.
6. Return to Run-Test/Idle.
7. Select the DR Scan path. The address will now have incremented by 1, 2, or 4 (corresponding
to the next byte, halfword, or word location).
8. In Shift-DR: For a read operation, scan out the contents of the next addressed location.
For a write operation, scan in the new contents of the next addressed location.
9. Go to Update-DR.
10. If the block access is not complete, return to Select-DR Scan and repeat the access.
11. If the block access is complete, return to Run-Test/Idle.
For write operations, 32 data bits must be provided, or the result will be undefined. For read
operations, shifting may be terminated once the required number of bits have been acquired.
DR output value (Address phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xeb
DR output value (Data read phase) xeb dddddddd dddddddd dddddddd dddddddd
DR output value (Data write phase) xxx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
Table 34-21. MEMORY_WORD_ACCESS Details (Continued)
Instructions Details
Table 34-22. MEMORY_BLOCK_ACCESS Details
Instructions Details
IR input value 10010 (0x12)
IR output value peb01
DR Size 34 bits
DR input value (Data read phase) xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx xx
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The overhead using block word access is 4 cycles per 32 bits of data, resulting in an 88% transfer
efficiency, or 2.1 MBytes per second with a 20 MHz TCK frequency.
34.5.3.6 CANCEL_ACCESS
If a very slow memory location is accessed during a SAB memory access, it could take a very
long time until the busy bit is cleared, and the SAB becomes ready for the next operation. The
CANCEL_ACCESS instruction provides a possibility to abort an ongoing transfer and report a
timeout to the JTAG master.
When the CANCEL_ACCESS instruction is selected, the current access will be terminated as
soon as possible. There are no guarantees about how long this will take, as the hardware may
not always be able to cancel the access immediately. The SAB is ready to respond to a new
command when the busy bit clears.
Starting in Run-Test/Idle, CANCEL_ACCESS is accessed in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
34.5.3.7 SYNC
This instruction allows external debuggers and testers to measure the ratio between the external
JTAG clock and the internal system clock. The SYNC data register is a 16-bit counter that
counts down to zero using the internal system clock. The busy bit stays high until the counter
reaches zero.
Starting in Run-Test/Idle, SYNC instruction is used in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
DR input value (Data write phase) dddddddd dddddddd dddddddd dddddddd xx
DR output value (Data read phase) eb dddddddd dddddddd dddddddd dddddddd
DR output value (Data write phase) xx xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxeb
Table 34-22. MEMORY_BLOCK_ACCESS Details (Continued)
Instructions Details
Table 34-23. CANCEL_ACCESS Details
Instructions Details
IR input value 10011 (0x13)
IR output value peb01
DR Size 1
DR input value x
DR output value 0
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6. Scan in an 16-bit counter value.
7. Go to Update-DR and re-enter Select-DR Scan.
8. In Shift-DR: Scan out the busy bit, and until the busy bit clears goto 7.
9. Calculate an approximation to the internal clock speed using the elapsed time and the
counter value.
10. Return to Run-Test/Idle.
The full 16-bit counter value must be provided when starting the synch operation, or the result
will be undefined. When reading status, shifting may be terminated once the required number of
bits have been acquired.
34.5.3.8 AVR_RESET
This instruction allows a debugger or tester to directly control separate reset domains inside the
chip. The shift register contains one bit for each controllable reset domain. Setting a bit to one
resets that domain and holds it in reset. Setting a bit to zero releases the reset for that domain.
The AVR_RESET instruction can be used in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
6. In Shift-DR: Scan in the value corresponding to the reset domains the JTAG master
wants to reset into the data register.
7. Return to Run-Test/Idle.
8. Stay in run test idle for at least 10 TCK clock cycles to let the reset propagate to the
system.
See the device specific documentation for the number of reset domains, and what these
domains are.
For any operation, all bits must be provided or the result will be undefined.
Table 34-24. SYNC_ACCESS Details
Instructions Details
IR input value 10111 (0x17)
IR output value peb01
DR Size 16 bits
DR input value dddddddd dddddddd
DR output value xxxxxxxx xxxxxxeb
Table 34-25. AVR_RESET Details
Instructions Details
IR input value 01100 (0x0C)
IR output value p0001
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34.5.3.9 CHIP_ERASE
This instruction allows a programmer to completely erase all nonvolatile memories in a chip.
This will also clear any security bits that are set, so the device can be accessed normally. In
devices without non-volatile memories this instruction does nothing, and appears to complete
immediately.
The erasing of non-volatile memories starts as soon as the CHIP_ERASE instruction is selected.
The CHIP_ERASE instruction selects a 1 bit bypass data register.
A chip erase operation should be performed as:
1. Reset the system and stop the CPU from executing.
2. Select the IR Scan path.
3. In Capture-IR: The IR output value is latched into the shift register.
4. In Shift-IR: The instruction register is shifted by the TCK input.
5. Check the busy bit that was scanned out during Shift-IR. If the busy bit was set goto 2.
6. Return to Run-Test/Idle.
34.5.3.10 HALT
This instruction allows a programmer to easily stop the CPU to ensure that it does not execute
invalid code during programming.
This instruction selects a 1-bit halt register. Setting this bit to one halts the CPU. Setting this bit
to zero releases the CPU to run normally. The value shifted out from the data register is one if
the CPU is halted. Before releasing the halt command the CPU needs to be reset to ensure that
it will start at the reset startup address.
The HALT instruction can be used in the following way:
1. Select the IR Scan path.
2. In Capture-IR: The IR output value is latched into the shift register.
3. In Shift-IR: The instruction register is shifted by the TCK input.
4. Return to Run-Test/Idle.
5. Select the DR Scan path.
DR Size Device specific.
DR input value Device specific.
DR output value Device specific.
Table 34-25. AVR_RESET Details (Continued)
Instructions Details
Table 34-26. CHIP_ERASE Details
Instructions Details
IR input value 01111 (0x0F)
IR output value p0b01
Where b is the busy bit.
DR Size 1 bit
DR input value x
DR output value 0
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6. In Shift-DR: Scan in the value 1 to halt the CPU, 0 to start CPU execution.
7. Return to Run-Test/Idle.
Table 34-27. HALT Details
Instructions Details
IR input value 11100 (0x1C)
IR output value p0001
DR Size 1 bit
DR input value d
DR output value d
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34.5.4 JTAG Data Registers
The following device specific registers can be selected as JTAG scan chain depending on the
instruction loaded in the JTAG Instruction Register. Additional registers exist, but are implicitly
described in the functional description of the relevant instructions.
34.5.4.1 Device Identification Register
The Device Identification Register contains a unique identifier for each product. The register is
selected by the IDCODE instruction, which is the default instruction after a JTAG reset.
Device specific ID codes
The different device configurations have different JTAG ID codes, as shown in Table 34-28.
Note that if the flash controller is statically reset, the ID code will be undefined.
34.5.4.2 Reset Register
The reset register is selected by the AVR_RESET instruction and contains one bit for each reset
domain in the device. Setting each bit to one will keep that domain reset until the bit is cleared.
MSB LSB
Bit 31 28 27 12 11 1 0
Device ID Revision Part Number Manufacturer ID 1
4 bits 16 bits 11 bits 1 bit
Revision This is a 4 bit number identifying the revision of the component.
Rev A = 0x0, B = 0x1, etc.
Part Number The part number is a 16 bit code identifying the component.
Manufacturer ID The Manufacturer ID is a 11 bit code identifying the manufacturer.
The JTAG manufacturer ID for ATMEL is 0x01F.
Table 34-28. Device and JTAG ID
Device Name JTAG ID Code (R is the revision number)
ATUC256L3U 0xr21C303F
ATUC128L3U 0xr21C403F
ATUC64L3U 0xr21C503F
ATUC256L4U 0xr21C603F
ATUC128L4U 0xr21C703F
ATUC64L4U 0xr21C803F
Bit 0
Reset
domain System
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34.5.4.3 Boundary--scan Chain
The boundary-scan chain has the capability of driving and observing the logic levels on the digital
I/O pins, as well as driving and observing the logic levels between the digital I/O pins and the
internal logic. Typically, output value, output enable, and input data are all available in the
boundary-scan chain.
The boundary-scan chain is described in the BSDL (Boundary Scan Description Language) file
available at the Atmel web site.
System Resets the whole chip, except the JTAG itself.
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34.6 aWire Debug Interface (AW)
Rev.: 2.3.0.1
34.6.1 Features
• Single pin debug system.
• Half Duplex asynchronous communication (UART compatible).
• Full duplex mode for direct UART connection.
• Compatible with JTAG functionality, except boundary scan.
• Failsafe packet-oriented protocol.
• Read and write on-chip memory and program on-chip flash and fuses through SAB interface.
• On-Chip Debug access through SAB interface.
• Asynchronous receiver or transmitter when the aWire system is not used for debugging.
34.6.2 Overview
The aWire Debug Interface (AW) offers a single pin debug solution that is fully compatible with
the functionality offered by the JTAG interface, except boundary scan. This functionality includes
memory access, programming capabilities, and On-Chip Debug access.
Figure 34-8 on page 881 shows how the AW is connected in a 32-bit AVR device. The
RESET_N pin is used both as reset and debug pin. A special sequence on RESET_N is needed
to block the normal reset functionality and enable the AW.
The Service Access Bus (SAB) interface contains address and data registers for the Service
Access Bus, which gives access to On-Chip Debug, programming, and other functions in the
device. The SAB offers several modes of access to the address and data registers, as discussed
in Section 34.6.6.8.
Section 34.6.7 lists the supported aWire commands and responses, with references to the
description in this document.
If the AW is not used for debugging, the aWire UART can be used by the user to send or receive
data with one stop bit, eight data bits, no parity bits, and one stop bit. This can be controlled
through the aWire user interface.
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34.6.3 Block Diagram
Figure 34-8. aWire Debug Interface Block Diagram
34.6.4 I/O Lines Description
34.6.5 Product Dependencies
In order to use this module, other parts of the system must be configured correctly, as described
below.
Table 34-29. I/O Lines Description
Name Description Type
DATA aWire data multiplexed with the RESET_N pin. Input/Output
DATAOUT aWire data output in 2-pin mode. Output
UART
Reset
filter
External reset
AW_ENABLE
RESET_N
Baudrate Detector
RW SZ ADDR DATA
CRC
AW CONTROL
AW User Interface
SAB interface
RESET command
Power
Manager
HALT command CPU
Flash
Controller CHIP_ERASE command
aWire Debug Interface
PB
SAB
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34.6.5.1 I/O Lines
The pin used by AW is multiplexed with the RESET_N pin. The reset functionality is the default
function of this pin. To enable the aWire functionality on the RESET_N pin the user must enable
the AW either by sending the enable sequence over the RESET_N pin from an external aWire
master or by enabling the aWire user interface.
In 2-pin mode data is received on the RESET_N line, but transmitted on the DATAOUT line.
After sending the 2_PIN_MODE command the DATAOUT line is automatically enabled. All other
peripheral functions on this pin is disabled.
34.6.5.2 Power Management
When debugging through AW the system clocks are automatically turned on to allow debugging
in sleep modes.
34.6.5.3 Clocks
The aWire UART uses the internal 120 MHz RC oscillator (RC120M) as clock source for its
operation. When enabling the AW the RC120M is automatically started.
34.6.5.4 External Components
The AW needs an external pullup on the RESET_N pin to ensure that the pin is pulled up when
the bus is not driven.
34.6.6 Functional Description
34.6.6.1 aWire Communication Protocol
The AW is accessed through the RESET_N pin shown in Table 34-29 on page 881. The AW
communicates through a UART operating at variable baud rate (depending on a sync pattern)
with one start bit, 8 data bits (LSB first), one stop bit, and no parity bits. The aWire protocol is
based upon command packets from an externalmaster and response packets from the slave
(AW). The master always initiates communication and decides the baud rate.
The packet contains a sync byte (0x55), a command/response byte, two length bytes (optional),
a number of data bytes as defined in the length field (optional), and two CRC bytes. If the command/response
has the most significant bit set, the command/response also carries the optional
length and data fields. The CRC field is not checked if the CRC value transmitted is 0x0000.
Table 34-30. aWire Packet Format
Field Number of bytes Description Comment Optional
SYNC 1 Sync pattern (0x55). Used by the receiver to set the baud rate
clock. No
COMMAND/
RESPONSE 1 Command from the master or
response from the slave.
When the most significant bit is set the
command/response has a length field. A
response has the next most significant bit
set. A command does not have this bit set.
No
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CRC calculation
The CRC is calculated from the command/response, length, and data fields. The polynomial
used is the FCS16 (or CRC-16-CCIT) in reverse mode (0x8408) and the starting value is
0x0000.
Example command
Below is an example command from the master with additional data.
Figure 34-9. Example Command
Example response
Below is an example response from the slave with additional data.
Figure 34-10. Example Response
LENGTH 2 The number of bytes in the DATA
field. Yes
DATA LENGTH Data according to command/
response.
Yes
CRC 2 CRC calculated with the FCS16
polynomial.
CRC value of 0x0000 makes the aWire
disregard the CRC if the master does not
support it.
No
Table 34-30. aWire Packet Format
Field Number of bytes Description Comment Optional
baud_rate_clk
data_pin ...
field sync(0x55) command(0x81) length(MSB) length(lsb)
...
data(MSB) data(LSB) CRC(MSB) CRC(lsb)
baud_rate_clk
data_pin ...
field sync(0x55) response(0xC1) length(MSB) length(lsb)
...
data(MSB) data(LSB) CRC(MSB) CRC(lsb)
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Avoiding drive contention when changing direction
The aWire debug protocol uses one dataline in both directions. To avoid both the master and the
slave to drive this line when changing direction the AW has a built in guard time before it starts to
drive the line. At reset this guard time is set to maximum (128 bit cycles), but can be lowered by
the master upon command.
The AW will release the line immediately after the stop character has been transmitted.
During the direction change there can be a period when the line is not driven. An external pullup
has to be added to RESET_N to keep the signal stable when neither master or slave is actively
driving the line.
34.6.6.2 The RESET_N pin
Normal reset functionality on the RESET_N pin is disabled when using aWire. However, the
user can reset the system through the RESET aWire command. During aWire operation the
RESET_N pin should not be connected to an external reset circuitry, but disconnected via a
switch or a jumper to avoid drive contention and speed problems.
Figure 34-11. Reset Circuitry and aWire.
34.6.6.3 Initializing the AW
To enable AW, the user has to send a 0x55 pattern with a baudrate of 1 kHz on the RESET_N
pin. The AW is enabled after transmitting this pattern and the user can start transmitting commands.
This pattern is not the sync pattern for the first command.
After enabling the aWire debug interface the halt bit is set automatically to prevent the system
from running code after the interface is enabled. To make the CPU run again set halt to zero
using the HALT command.
34.6.6.4 Disabling the AW
To disable AW, the user can keep the RESET_N pin low for 100 ms. This will disable the AW,
return RESET_N to its normal function, and reset the device.
An aWire master can also disable aWire by sending the DISABLE command. After acking the
command the AW will be disabled and RESET_N returns to its normal function.
RESET_N
AW Debug
Interface
Jumper
MCU
Power Manager
aWire master connector
Board Reset
Circuitry
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34.6.6.5 Resetting the AW
The aWire master can reset the AW slave by pulling the RESET_N pin low for 20 ms. This is
equivalent to disabling and then enabling AW.
34.6.6.6 2-pin Mode
To avoid using special hardware when using a normal UART device as aWire master, the aWire
slave has a 2-pin mode where one pin is used as input and on pin is used as output. To enable
this mode the 2_PIN_MODE command must be sent. After sending the command, all responses
will be sent on the DATAOUT pin instead of the RESET_N pin. Commands are still received on
the RESET_N pin.
34.6.6.7 Baud Rate Clock
The communication speed is set by the master in the sync field of the command. The AW will
use this to resynchronize its baud rate clock and reply on this frequency. The minimum frequency
of the communication is 1 kHz. The maximum frequency depends on the internal clock
source for the AW (RC120M). The baud rate clock is generated by AW with the following
formula:
Where is the baud rate frequency and is the frequency of the internal RC120M. TUNE is
the value returned by the BAUD_RATE response.
To find the max frequency the user can issue the TUNE command to the AW to make it return
the TUNE value. This value can be used to compute the . The maximum operational frequency
( ) is then:
34.6.6.8 Service Access Bus
The AVR32 architecture offers a common interface for access to On-Chip Debug, programming,
and test functions. These are mapped on a common bus called the Service Access Bus (SAB),
which is linked to the aWire through a bus master module, which also handles synchronization
between the aWire and SAB clocks.
For more information about the SAB and a list of SAB slaves see the Service Access Bus
chapter.
SAB Clock
When accessing the SAB through the aWire there are no limitations on baud rate frequency
compared to chip frequency, although there must be an active system clock in order for the SAB
accesses to complete. If the system clock (CLK_SYS) is switched off in sleep mode, activity on
the aWire pin will restart the CLK_SYS automatically, without waking the device from sleep.
aWire masters may optimize the transfer rate by adjusting the baud rate frequency in relation to
the CLK_SYS. This ratio can be measured with the MEMORY_SPEED_REQUEST command.
When issuing the MEMORY_SPEED_REQUEST command a counter value CV is returned. CV
can be used to calculate the SAB speed ( ) using this formula:
f
aw
TUNE f br
8 = ----------------------------
f
br f
aw
f
aw
f
brmax
f
brmax
f
aw
4 = -------
f
sab
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SAB Address Mode
The Service Access Bus uses 36 address bits to address memory or registers in any of the
slaves on the bus. The bus supports sized accesses of bytes (8 bits), halfwords (16 bits), or
words (32 bits). All accesses must be aligned to the size of the access, i.e. halfword accesses
must have the lowest address bit cleared, and word accesses must have the two lowest address
bits cleared.
Two instructions exist to access the SAB: MEMORY_WRITE and MEMORY_READ. These two
instructions write and read words, halfwords, and bytes from the SAB.
Busy Reporting
If the aWire master, during a MEMORY_WRITE or a MEMORY_READ command, transmit
another byte when the aWire is still busy sending the previous byte to the SAB, the AW will
respond with a MEMORY_READ_WRITE_STATUS error. See chapter Section 34.6.8.5 for
more details.
The aWire master should adjust its baudrate or delay between bytes when doing SAB accesses
to ensure that the SAB is not overwhelmed with data.
Error Reporting
If a write is performed on a non-existing memory location the SAB interface will respond with an
error. If this happens, all further writes in this command will not be performed and the error and
number of bytes written is reported in the MEMORY_READWRITE_STATUS message from the
AW after the write.
If a read is performed on a non-existing memory location, the SAB interface will respond with an
error. If this happens, the data bytes read after this event are not valid. The AW will include three
extra bytes at the end of the transfer to indicate if the transfer was successful, or in the case of
an error, how many valid bytes were received.
34.6.6.9 CRC Errors/NACK Response
The AW will calculate a CRC value when receiving the command, length, and data fields of the
command packets. If this value differs from the value from the CRC field of the packet, the AW
will reply with a NACK response. Otherwise the command is carried out normally.
An unknown command will be replied with a NACK response.
In worst case a transmission error can happen in the length or command field of the packet. This
can lead to the aWire slave trying to receive a command with or without length (opposite of what
the master intended) or receive an incorrect number of bytes. The aWire slave will then either
wait for more data when the master has finished or already have transmitted the NACK
response in congestion with the master. The master can implement a timeout on every command
and reset the slave if no response is returned after the timeout period has ended.
f
sab
3f
aw
CV – 3 = ----------------
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34.6.7 aWire Command Summary
The implemented aWire commands are shown in the table below. The responses from the AW
are listed in Section 34.6.8.
All aWire commands are described below, with a summary in table form.
34.6.7.1 AYA
This command asks the AW: “Are you alive”, where the AW should respond with an
acknowledge.
Table 34-31. aWire Command Summary
COMMAND Instruction Description
0x01 AYA “Are you alive”.
0x02 JTAG_ID Asks AW to return the JTAG IDCODE.
0x03 STATUS_REQUEST Request a status message from the AW.
0x04 TUNE Tell the AW to report the current baud rate.
0x05 MEMORY_SPEED_REQUEST Reports the speed difference between the aWire control and the SAB clock
domains.
0x06 CHIP_ERASE Erases the flash and all volatile memories.
0x07 DISABLE Disables the AW.
0x08 2_PIN_MODE Enables the DATAOUT pin and puts the aWire in 2-pin mode, where all
responses are sent on the DATAOUT pin.
0x80 MEMORY_WRITE Writes words, halfwords, or bytes to the SAB.
0x81 MEMORY_READ Reads words, halfwords, or bytes from the SAB.
0x82 HALT Issues a halt command to the device.
0x83 RESET Issues a reset to the Reset Controller.
0x84 SET_GUARD_TIME Sets the guard time for the AW.
Table 34-32. Command/Response Description Notation
Command/Response Description
Command/Response value Shows the command/response value to put into the command/response field of the packet.
Additional data Shows the format of the optional data field if applicable.
Possible responses Shows the possible responses for this command.
Table 34-33. AYA Details
Command Details
Command value 0x01
Additional data N/A
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
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34.6.7.2 JTAG_ID
This command instructs the AW to output the JTAG idcode in the following response.
34.6.7.3 STATUS_REQUEST
Asks the AW for a status message.
34.6.7.4 TUNE
Asks the AW for the current baud rate counter value.
34.6.7.5 MEMORY_SPEED_REQUEST
Asks the AW for the relative speed between the aWire clock (RC120M) and the SAB interface.
34.6.7.6 CHIP_ERASE
This instruction allows a programmer to completely erase all nonvolatile memories in the chip.
This will also clear any security bits that are set, so the device can be accessed normally. The
command is acked immediately, but the status of the command can be monitored by checking
Table 34-34. JTAG_ID Details
Command Details
Command value 0x02
Additional data N/A
Possible responses 0xC0: IDCODE (Section 34.6.8.3)
0x41: NACK (Section 34.6.8.2)
Table 34-35. STATUS_REQUEST Details
Command Details
Command value 0x03
Additional data N/A
Possible responses 0xC4: STATUS_INFO (Section 34.6.8.7)
0x41: NACK (Section 34.6.8.2)
Table 34-36. TUNE Details
Command Details
Command value 0x04
Additional data N/A
Possible responses 0xC3: BAUD_RATE (Section 34.6.8.6)
0x41: NACK (Section 34.6.8.2)
Table 34-37. MEMORY_SPEED_REQUEST Details
Command Details
Command value 0x05
Additional data N/A
Possible responses 0xC5: MEMORY_SPEED (Section 34.6.8.8)
0x41: NACK (Section 34.6.8.2)
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the Chip Erase ongoing bit in the status bytes received after the STATUS_REQUEST
command.
34.6.7.7 DISABLE
Disables the AW. The AW will respond with an ACK response and then disable itself.
34.6.7.8 2_PIN_MODE
Enables the DATAOUT pin as an output pin. All responses sent from the aWire slave will be sent
on this pin, instead of the RESET_N pin, starting with the ACK for the 2_PIN_MODE command.
34.6.7.9 MEMORY_WRITE
This command enables programming of memory/writing to registers on the SAB. The
MEMORY_WRITE command allows words, halfwords, and bytes to be programmed to a continuous
sequence of addresses in one operation. Before transferring the data, the user must
supply:
1. The number of data bytes to write + 5 (size and starting address) in the length field.
2. The size of the transfer: words, halfwords, or bytes.
3. The starting address of the transfer.
Table 34-38. CHIP_ERASE Details
Command Details
Command value 0x06
Additional data N/A
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
Table 34-39. DISABLE Details
Command Details
Command value 0x07
Additional data N/A
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
Table 34-40. DISABLE Details
Command Details
Command value 0x07
Additional data N/A
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
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The 4 MSB of the 36 bit SAB address are submitted together with the size field (2 bits). Then follows
the 4 remaining address bytes and finally the data bytes. The size of the transfer is
specified using the values from the following table:
Below is an example write command:
1. 0x55 (sync)
2. 0x80 (command)
3. 0x00 (length MSB)
4. 0x09 (length LSB)
5. 0x25 (size and address MSB, the two MSB of this byte are unused and set to zero)
6. 0x00
7. 0x00
8. 0x00
9. 0x04 (address LSB)
10. 0xCA
11. 0xFE
12. 0xBA
13. 0xBE
14. 0xXX (CRC MSB)
15. 0xXX (CRC LSB)
The length field is set to 0x0009 because there are 9 bytes of additional data: 5 address and size
bytes and 4 bytes of data. The address and size field indicates that words should be written to
address 0x500000004. The data written to 0x500000004 is 0xCAFEBABE.
34.6.7.10 MEMORY_READ
This command enables reading of memory/registers on the Service Access Bus (SAB). The
MEMORY_READ command allows words, halfwords, and bytes to be read from a continuous
sequence of addresses in one operation. The user must supply:
Table 34-41. Size Field Decoding
Size field Description
00 Byte transfer
01 Halfword transfer
10 Word transfer
11 Reserved
Table 34-42. MEMORY_WRITE Details
Command Details
Command value 0x80
Additional data Size, Address and Data
Possible responses 0xC2: MEMORY_READWRITE_STATUS (Section 34.6.8.5)
0x41: NACK (Section 34.6.8.2)
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1. The size of the data field: 7 (size and starting address + read length indicator) in the
length field.
2. The size of the transfer: Words, halfwords, or bytes.
3. The starting address of the transfer.
4. The number of bytes to read (max 65532).
The 4 MSB of the 36 bit SAB address are submitted together with the size field (2 bits). The 4
remaining address bytes are submitted before the number of bytes to read. The size of the
transfer is specified using the values from the following table:
Below is an example read command:
1. 0x55 (sync)
2. 0x81 (command)
3. 0x00 (length MSB)
4. 0x07 (length LSB)
5. 0x25 (size and address MSB, the two MSB of this byte are unused and set to zero)
6. 0x00
7. 0x00
8. 0x00
9. 0x04 (address LSB)
10. 0x00
11. 0x04
12. 0xXX (CRC MSB)
13. 0xXX (CRC LSB)
The length field is set to 0x0007 because there are 7 bytes of additional data: 5 bytes of address
and size and 2 bytes with the number of bytes to read. The address and size field indicates one
word (four bytes) should be read from address 0x500000004.
Table 34-43. Size Field Decoding
Size field Description
00 Byte transfer
01 Halfword transfer
10 Word transfer
11 Reserved
Table 34-44. MEMORY_READ Details
Command Details
Command value 0x81
Additional data Size, Address and Length
Possible responses
0xC1: MEMDATA (Section 34.6.8.4)
0xC2: MEMORY_READWRITE_STATUS (Section 34.6.8.5)
0x41: NACK (Section 34.6.8.2)
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34.6.7.11 HALT
This command tells the CPU to halt code execution for safe programming. If the CPU is not
halted during programming it can start executing partially loaded programs. To halt the processor,
the aWire master should send 0x01 in the data field of the command. After programming the
halting can be released by sending 0x00 in the data field of the command.
34.6.7.12 RESET
This command resets different domains in the part. The aWire master sends a byte with the
reset value. Each bit in the reset value byte corresponds to a reset domain in the chip. If a bit is
set the reset is activated and if a bit is not set the reset is released. The number of reset domains
and their destinations are identical to the resets described in the JTAG data registers chapter
under reset register.
34.6.7.13 SET_GUARD_TIME
Sets the guard time value in the AW, i.e. how long the AW will wait before starting its transfer
after the master has finished.
The guard time can be either 0x00 (128 bit lengths), 0x01 (16 bit lengths), 0x2 (4 bit lengths) or
0x3 (1 bit length).
Table 34-45. HALT Details
Command Details
Command value 0x82
Additional data 0x01 to halt the CPU 0x00 to release the halt and reset the
device.
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
Table 34-46. RESET Details
Command Details
Command value 0x83
Additional data Reset value for each reset domain. The number of reset
domains is part specific.
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
Table 34-47. SET_GUARD_TIME Details
Command Details
Command value 0x84
Additional data Guard time
Possible responses 0x40: ACK (Section 34.6.8.1)
0x41: NACK (Section 34.6.8.2)
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34.6.8 aWire Response Summary
The implemented aWire responses are shown in the table below.
34.6.8.1 ACK
The AW has received the command successfully and performed the operation.
34.6.8.2 NACK
The AW has received the command, but got a CRC mismatch.
34.6.8.3 IDCODE
The JTAG idcode for this device.
34.6.8.4 MEMDATA
The data read from the address specified by the MEMORY_READ command. The last 3 bytes
are status bytes from the read. The first status byte is the status of the command described in
the table below. The last 2 bytes are the number of remaining data bytes to be sent in the data
field of the packet when the error occurred. If the read was not successful all data bytes after the
failure are undefined. A successful word read (4 bytes) will look like this:
Table 34-48. aWire Response Summary
RESPONSE Instruction Description
0x40 ACK Acknowledge.
0x41 NACK Not acknowledge. Sent after CRC errors and after unknown commands.
0xC0 IDCODE The JTAG idcode.
0xC1 MEMDATA Values read from memory.
0xC2 MEMORY_READWRITE_STATUS Status after a MEMORY_WRITE or a MEMORY_READ command. OK, busy,
error.
0xC3 BAUD_RATE The current baudrate.
0xC4 STATUS_INFO Status information.
0xC5 MEMORY_SPEED SAB to aWire speed information.
Table 34-49. ACK Details
Response Details
Response value 0x40
Additional data N/A
Table 34-50. NACK Details
Response Details
Response value 0x41
Additional data N/A
Table 34-51. IDCODE Details
Response Details
Response value 0xC0
Additional data JTAG idcode
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1. 0x55 (sync)
2. 0xC1 (command)
3. 0x00 (length MSB)
4. 0x07 (length LSB)
5. 0xCA (Data MSB)
6. 0xFE
7. 0xBA
8. 0xBE (Data LSB)
9. 0x00 (Status byte)
10. 0x00 (Bytes remaining MSB)
11. 0x00 (Bytes remaining LSB)
12. 0xXX (CRC MSB)
13. 0xXX (CRC LSB)
The status is 0x00 and all data read are valid. An unsuccessful four byte read can look like this:
1. 0x55 (sync)
2. 0xC1 (command)
3. 0x00 (length MSB)
4. 0x07 (length LSB)
5. 0xCA (Data MSB)
6. 0xFE
7. 0xXX (An error has occurred. Data read is undefined. 5 bytes remaining of the Data
field)
8. 0xXX (More undefined data)
9. 0x02 (Status byte)
10. 0x00 (Bytes remaining MSB)
11. 0x05 (Bytes remaining LSB)
12. 0xXX (CRC MSB)
13. 0xXX (CRC LSB)
The error occurred after reading 2 bytes on the SAB. The rest of the bytes read are undefined.
The status byte indicates the error and the bytes remaining indicates how many bytes were
remaining to be sent of the data field of the packet when the error occurred.
Table 34-52. MEMDATA Status Byte
status byte Description
0x00 Read successful
0x01 SAB busy
0x02 Bus error (wrong address)
Other Reserved
Table 34-53. MEMDATA Details
Response Details
Response value 0xC1
Additional data Data read, status byte, and byte count (2 bytes)
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34.6.8.5 MEMORY_READWRITE_STATUS
After a MEMORY_WRITE command this response is sent by AW. The response can also be
sent after a MEMORY_READ command if AW encountered an error when receiving the
address. The response contains 3 bytes, where the first is the status of the command and the 2
next contains the byte count when the first error occurred. The first byte is encoded this way:
34.6.8.6 BAUD_RATE
The current baud rate in the AW. See Section 34.6.6.7 for more details.
34.6.8.7 STATUS_INFO
A status message from AW.
Table 34-54. MEMORY_READWRITE_STATUS Status Byte
status byte Description
0x00 Write successful
0x01 SAB busy
0x02 Bus error (wrong address)
Other Reserved
Table 34-55. MEMORY_READWRITE_STATUS Details
Response Details
Response value 0xC2
Additional data Status byte and byte count (2 bytes)
Table 34-56. BAUD_RATE Details
Response Details
Response value 0xC3
Additional data Baud rate
Table 34-57. STATUS_INFO Contents
Bit number Name Description
15-9 Reserved
8 Protected The protection bit in the internal flash is set. SAB access is restricted. This bit
will read as one during reset.
7 SAB busy
The SAB bus is busy with a previous transfer. This could indicate that the CPU
is running on a very slow clock, the CPU clock has stopped for some reason
or that the part is in constant reset.
6 Chip erase ongoing The Chip erase operation has not finished.
5 CPU halted This bit will be set if the CPU is halted. This bit will read as zero during reset.
4-1 Reserved
0 Reset status This bit will be set if AW has reset the CPU using the RESET command.
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34.6.8.8 MEMORY_SPEED
Counts the number of RC120M clock cycles it takes to sync one message to the SAB interface
and back again. The SAB clock speed ( ) can be calculated using the following formula:
34.6.9 Security Restrictions
When the security fuse in the Flash is programmed, the following aWire commands are limited:
• MEMORY_WRITE
• MEMORY_READ
Unlimited access to these instructions is restored when the security fuse is erased by the
CHIP_ERASE aWire command.
Note that the security bit will read as programmed and block these instructions also if the Flash
Controller is statically reset.
Table 34-58. STATUS_INFO Details
Response Details
Response value 0xC4
Additional data 2 status bytes
Table 34-59. MEMORY_SPEED Details
Response Details
Response value 0xC5
Additional data Clock cycle count (MS)
f
sab
f
sab
3f
aw
CV – 3 = ----------------
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35. Electrical Characteristics
35.1 Absolute Maximum Ratings*
Notes: 1. 5V tolerant pins, see Section ”Peripheral Multiplexing on I/O lines” on page 10
2. VVDD corresponds to either VVDDIN or VVDDIO, depending on the supply for the pin. Refer to Section on page 10 for details.
35.2 Supply Characteristics
The following characteristics are applicable to the operating temperature range: TA = -40°C to
85°C, unless otherwise specified and are valid for a junction temperature up to TJ = 100°C.
Please refer to Section 6. ”Supply and Startup Considerations” on page 39.
Table 35-1. Absolute Maximum Ratings
Operating temperature..................................... -40C to +85C *NOTICE: Stresses beyond those listed under
“Absolute Maximum Ratings” may cause
permanent damage to the device. This is
a stress rating only and functional operation
of the device at these or other conditions
beyond those indicated in the
operational sections of this specification is
not implied. Exposure to absolute maximum
rating conditions for extended periods
may affect device reliability.
Storage temperature...................................... -60°C to +150°C
Voltage on input pins (except for 5V pins) with respect to ground
.................................................................-0.3V to VVDD(2)+0.3V
Voltage on 5V tolerant(1) pins with respect to ground ...............
.............................................................................-0.3V to 5.5V
Total DC output current on all I/O pins - VDDIO, 64-pin package
............... ......................................................................141 mA
Total DC output current on all I/O pins - VDDIN, 64-pin package
....................................................................................... 42 mA
Total DC output current on all I/O pins - VDDIO, 48-pin package
........... ...........................................................................120mA
Total DC output current on all I/O pins - VDDIN, 48-pin package
....................................................................................... 39 mA
Maximum operating voltage VDDCORE......................... 1.98V
Maximum operating voltage VDDIO, VDDIN .................... 3.6V
Table 35-2. Supply Characteristics
Symbol Parameter
Voltage
Min Max Unit
VVDDIO DC supply peripheral I/Os 1.62 3.6 V
VVDDIN
DC supply peripheral I/Os, 1.8V
single supply mode 1.62 1.98 V
DC supply peripheral I/Os and
internal regulator, 3.3V supply
mode
1.98 3.6 V
VVDDCORE DC supply core 1.62 1.98 V
VVDDANA Analog supply voltage 1.62 1.98 V
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Note: 1. These values are based on simulation and characterization of other AVR microcontrollers
manufactured in the same process technology. These values are not covered by test limits in
production.
35.3 Maximum Clock Frequencies
These parameters are given in the following conditions:
• VVDDCORE = 1.62V to 1.98V
• Temperature = -40°C to 85°C
35.4 Power Consumption
The values in Table 35-5 are measured values of power consumption under the following conditions,
except where noted:
• Operating conditions, internal core supply (Figure 35-1) - this is the default configuration
– VVDDIN = 3.0V
Table 35-3. Supply Rise Rates and Order(1)
Symbol Parameter
Rise Rate
Min Max Unit Comment
VVDDIO DC supply peripheral I/Os 0 2.5 V/µs
VVDDIN
DC supply peripheral I/Os
and internal regulator 0.002 2.5 V/µs
Slower rise time requires
external power-on reset
circuit.
VVDDCORE DC supply core 0 2.5 V/µs Rise before or at the same
time as VDDIO
VVDDANA Analog supply voltage 0 2.5 V/µs Rise together with
VDDCORE
Table 35-4. Clock Frequencies
Symbol Parameter Description Min Max Units
fCPU CPU clock frequency 50
MHz
fPBA PBA clock frequency 50
fPBB PBB clock frequency 50
fGCLK0 GCLK0 clock frequency DFLLIF main reference, GCLK0 pin 50
fGCLK1 GCLK1 clock frequency DFLLIF dithering and SSG reference, GCLK1 pin 50
fGCLK2 GCLK2 clock frequency AST, GCLK2 pin 20
fGCLK3 GCLK3 clock frequency PWMA, GCLK3 pin 140
fGCLK4 GCLK4 clock frequency CAT, ACIFB, GCLK4 pin 50
fGCLK5 GCLK5 clock frequency GLOC and GCLK5 pin 80
fGCLK6 GCLK6 clock frequency ABDACB, IISC, and GCLK6 pin 50
fGCLK7 GCLK7 clock frequency USBC and GCLK7 pin 50
fGCLK8 GCLK8 clock frequency PLL0 source clock and GCLK8 pin 50
fGCLK9 GCLK9 clock frequency FREQM, GCLK0-8, GCLK9 pin 150
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– VVDDCORE = 1.62V, supplied by the internal regulator
– Corresponds to the 3.3V supply mode with 1.8V regulated I/O lines, please refer to
the Supply and Startup Considerations section for more details
• Equivalent to the 3.3V single supply mode
• Consumption in 1.8V single supply mode can be estimated by subtracting the regulator
static current
• Operating conditions, external core supply (Figure 35-2) - used only when noted
– VVDDIN = VVDDCORE = 1.8V
– Corresponds to the 1.8V single supply mode, please refer to the Supply and Startup
Considerations section for more details
• TA = 25C
• Oscillators
– OSC0 (crystal oscillator) stopped
– OSC32K (32KHz crystal oscillator) running with external 32KHz crystal
– DFLL running at 50MHz with OSC32K as reference
• Clocks
– DFLL used as main clock source
– CPU, HSB, and PBB clocks undivided
– PBA clock divided by 4
– The following peripheral clocks running
• PM, SCIF, AST, FLASHCDW, PBA bridge
– All other peripheral clocks stopped
• I/Os are inactive with internal pull-up
• Flash enabled in high speed mode
• POR18 enabled
• POR33 disabled
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Note: 1. These numbers are valid for the measured condition only and must not be extrapolated to other frequencies.
Figure 35-1. Measurement Schematic, Internal Core Supply
Table 35-5. Power Consumption for Different Operating Modes
Mode Conditions Measured on Consumption Typ Unit
Active(1) CPU running a recursive Fibonacci algorithm
Amp0
300
µA/MHz
CPU running a division algorithm 174
Idle(1) 96
Frozen(1) 57
Standby(1) 46
Stop 38
µA
DeepStop 25
Static
-OSC32K and AST stopped
-Internal core supply
14
-OSC32K running
-AST running at 1KHz
-External core supply (Figure 35-2)
7.3
-OSC32K and AST stopped
-External core supply (Figure 35-2) 6.7
Shutdown
-OSC32K running
-AST running at 1KHz 800
nA
AST and OSC32K stopped 220
Amp0 VDDIN
VDDCORE
VDDANA
VDDIO
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Figure 35-2. Measurement Schematic, External Core Supply
Amp0 VDDIN
VDDCORE
VDDANA
VDDIO
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35.5 I/O Pin Characteristics
Notes: 1. VVDD corresponds to either VVDDIN or VVDDIO, depending on the supply for the pin. Refer to Section on page 10 for details.
2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Table 35-6. Normal I/O Pin Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
RPULLUP Pull-up resistance 75 100 145 kOhm
VIL Input low-level voltage
VVDD = 3.0V -0.3 0.3 * VVDD V
VVDD = 1.62V -0.3 0.3 * VVDD
VIH Input high-level voltage
VVDD = 3.6V 0.7 * VVDD VVDD + 0.3
V
VVDD = 1.98V 0.7 * VVDD VVDD + 0.3
VOL Output low-level voltage
VVDD = 3.0V, IOL = 3mA 0.4
V
VVDD = 1.62V, IOL = 2mA 0.4
VOH Output high-level voltage
VVDD = 3.0V, IOH = 3mA VVDD - 0.4
V
VVDD = 1.62V, IOH = 2mA VVDD - 0.4
fMAX Output frequency(2)
VVDD = 3.0V, load = 10pF 45
MHz
VVDD = 3.0V, load = 30pF 23
tRISE Rise time(2)
VVDD = 3.0V, load = 10pF 4.7
ns
VVDD = 3.0V, load = 30pF 11.5
tFALL Fall time(2)
VVDD = 3.0V, load = 10pF 4.8
VVDD = 3.0V, load = 30pF 12
ILEAK Input leakage current Pull-up resistors disabled 1 µA
CIN
Input capacitance, all
normal I/O pins except
PA05, PA07, PA17, PA20,
PA21, PB04, PB05
TQFP48 package 1.4
pF
QFN48 package 1.1
TLLGA48 package 1.1
TQFP64 package 1.5
QFN64 package 1.1
CIN Input capacitance, PA20
TQFP48 package 2.7
QFN48 package 2.4
TLLGA48 package 2.4
TQFP64 package 2.8
QFN64 package 2.4
CIN
Input capacitance, PA05,
PA07, PA17, PA21, PB04,
PB05
TQFP48 package 3.8
QFN48 package 3.5
TLLGA48 package 3.5
TQFP64 package 3.9
QFN64 package 3.5
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Notes: 1. VVDD corresponds to either VVDDIN or VVDDIO, depending on the supply for the pin. Refer to Section on page 10 for details.
Table 35-7. High-drive I/O Pin Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
RPULLUP Pull-up resistance
PA06 30 50 110
PA02, PB01, RESET 75 100 145 kOhm
PA08, PA09 10 20 45
VIL Input low-level voltage
VVDD = 3.0V -0.3 0.3 * VVDD V
VVDD = 1.62V -0.3 0.3 * VVDD
VIH Input high-level voltage
VVDD = 3.6V 0.7 * VVDD VVDD + 0.3
V
VVDD = 1.98V 0.7 * VVDD VVDD + 0.3
VOL Output low-level voltage
VVDD = 3.0V, IOL = 6mA 0.4
V
VVDD = 1.62V, IOL = 4mA 0.4
VOH Output high-level voltage
VVDD = 3.0V, IOH = 6mA VVDD - 0.4
V
VVDD = 1.62V, IOH = 4mA VVDD - 0.4
fMAX
Output frequency, all High-drive I/O
pins, except PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 45
MHz
VVDD = 3.0V, load = 30pF 23
tRISE
Rise time, all High-drive I/O pins, except
PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 4.7
ns
VVDD = 3.0V, load = 30pF 11.5
tFALL
Fall time, all High-drive I/O pins, except
PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 4.8
VVDD = 3.0V, load = 30pF 12
fMAX Output frequency, PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 54
MHz
VVDD = 3.0V, load = 30pF 40
tRISE Rise time, PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 2.8
ns
VVDD = 3.0V, load = 30pF 4.9
tFALL Fall time, PA08 and PA09(2)
VVDD = 3.0V, load = 10pF 2.4
VVDD = 3.0V, load = 30pF 4.6
ILEAK Input leakage current Pull-up resistors disabled 1 µA
CIN
Input capacitance, all High-drive I/O
pins, except PA08 and PA09
TQFP48 package 2.2
pF
QFN48 package 2.0
TLLGA48 package 2.0
TQFP64 package 2.3
QFN64 package 2.0
CIN Input capacitance, PA08 and PA09
TQFP48 package 7.0
QFN48 package 6.7
TLLGA48 package 6.7
TQFP64 package 7.1
QFN64 package 6.7
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2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Notes: 1. VVDD corresponds to either VVDDIN or VVDDIO, depending on the supply for the pin. Refer to Section on page 10 for details.
2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Table 35-8. High-drive I/O, 5V Tolerant, Pin Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
RPULLUP Pull-up resistance 30 50 110 kOhm
VIL Input low-level voltage
VVDD = 3.0V -0.3 0.3 * VVDD V
VVDD = 1.62V -0.3 0.3 * VVDD
VIH Input high-level voltage
VVDD = 3.6V 0.7 * VVDD 5.5
V
VVDD = 1.98V 0.7 * VVDD 5.5
VOL Output low-level voltage
VVDD = 3.0V, IOL = 6mA 0.4
V
VVDD = 1.62V, IOL = 4mA 0.4
VOH Output high-level voltage
VVDD = 3.0V, IOH = 6mA VVDD - 0.4
V
VVDD = 1.62V, IOH = 4mA VVDD - 0.4
fMAX Output frequency(2)
VVDD = 3.0V, load = 10pF 87
MHz
VVDD = 3.0V, load = 30pF 58
tRISE Rise time(2)
VVDD = 3.0V, load = 10pF 2.3
ns
VVDD = 3.0V, load = 30pF 4.3
tFALL Fall time(2)
VVDD = 3.0V, load = 10pF 1.9
VVDD = 3.0V, load = 30pF 3.7
ILEAK Input leakage current 5.5V, pull-up resistors disabled 10 µA
CIN Input capacitance
TQFP48 package 4.5
pF
QFN48 package 4.2
TLLGA48 package 4.2
TQFP64 package 4.6
QFN64 package 4.2
Table 35-9. TWI Pin Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
RPULLUP Pull-up resistance 25 35 60 kOhm
VIL Input low-level voltage
VVDD = 3.0V -0.3 0.3 * VVDD V
VVDD = 1.62V -0.3 0.3 * VVDD
VIH
Input high-level voltage
VVDD = 3.6V 0.7 * VVDD VVDD + 0.3
V
VVDD = 1.98V 0.7 * VVDD VVDD + 0.3
Input high-level voltage, 5V tolerant
SMBUS compliant pins
VVDD = 3.6V 0.7 * VVDD 5.5
V
VVDD = 1.98V 0.7 * VVDD 5.5
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Note: 1. VVDD corresponds to either VVDDIN or VVDDIO, depending on the supply for the pin. Refer to Section on page 10 for details.
35.6 Oscillator Characteristics
35.6.1 Oscillator 0 (OSC0) Characteristics
35.6.1.1 Digital Clock Characteristics
The following table describes the characteristics for the oscillator when a digital clock is applied
on XIN.
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.6.1.2 Crystal Oscillator Characteristics
The following table describes the characteristics for the oscillator when a crystal is connected
between XIN and XOUT as shown in Figure 35-3. The user must choose a crystal oscillator
where the crystal load capacitance CL is within the range given in the table. The exact value of CL
VOL Output low-level voltage IOL = 3mA 0.4 V
ILEAK Input leakage current Pull-up resistors disabled 1
IIL Input low leakage 1 µA
IIH Input high leakage 1
CIN Input capacitance
TQFP48 package 3.8
pF
QFN48 package 3.5
TLLGA48 package 3.5
TQFP64 package 3.9
QFN64 package 3.5
tFALL Fall time
Cbus = 400pF, VVDD > 2.0V 250
ns
Cbus = 400pF, VVDD > 1.62V 470
fMAX Max frequency Cbus = 400pF, VVDD > 2.0V 400 kHz
Table 35-9. TWI Pin Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
Table 35-10. Digital Clock Characteristics
Symbol Parameter Conditions Min Typ Max Units
fCPXIN XIN clock frequency 50 MHz
tCPXIN XIN clock duty cycle(1) 40 60 %
tSTARTUP Startup time 0 cycles
CIN XIN input capacitance
TQFP48 package 7.0
pF
QFN48 package 6.7
TLLGA48 package 6.7
TQFP64 package 7.1
QFN64 package 6.7
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can be found in the crystal datasheet. The capacitance of the external capacitors (CLEXT) can
then be computed as follows:
where CPCB is the capacitance of the PCB and Ci
is the internal equivalent load capacitance.
Notes: 1. Please refer to the SCIF chapter for details.
2. Nominal crystal cycles.
3. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Figure 35-3. Oscillator Connection
CLEXT 2 CL Ci – CPCB = –
Table 35-11. Crystal Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Crystal oscillator frequency(3) 0.45 10 16 MHz
CL Crystal load capacitance(3) 6 18
pF
Ci Internal equivalent load capacitance 2
tSTARTUP Startup time SCIF.OSCCTRL.GAIN = 2(1) 30 000(2) cycles
IOSC Current consumption
Active mode, f = 0.45MHz,
SCIF.OSCCTRL.GAIN = 0 30
µA Active mode, f = 10MHz,
SCIF.OSCCTRL.GAIN = 2 220
XIN
XOUT
CLEXT
CLEXT
CL
Ci
UC3L
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35.6.2 32KHz Crystal Oscillator (OSC32K) Characteristics
Figure 35-3 and the equation above also applies to the 32KHz oscillator connection. The user
must choose a crystal oscillator where the crystal load capacitance CL is within the range given
in the table. The exact value of CL can then be found in the crystal datasheet.
Notes: 1. Nominal crystal cycles.
2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.6.3 Phase Locked Loop (PLL) Characteristics
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Table 35-12. 32 KHz Crystal Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Crystal oscillator frequency 32 768 Hz
tSTARTUP Startup time RS = 60kOhm, CL = 9pF 30 000(1) cycles
CL Crystal load capacitance(2) 6 12.5
pF Ci
Internal equivalent load
capacitance 2
IOSC32 Current consumption 0.6 µA
RS Equivalent series resistance(2) 32 768Hz 35 85 kOhm
Table 35-13. Phase Locked Loop Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Output frequency(1) 40 240
MHz
fIN Input frequency(1) 4 16
IPLL Current consumption 8 µA/MHz
tSTARTUP
Startup time, from enabling
the PLL until the PLL is
locked
fIN= 4MHz 200
µs
fIN= 16MHz 155
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35.6.4 Digital Frequency Locked Loop (DFLL) Characteristics
Notes: 1. Spread Spectrum Generator (SSG) is disabled by writing a zero to the EN bit in the DFLL0SSG register.
2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
3. The FINE and COARSE values are selected by wrirting to the DFLL0VAL.FINE and DFLL0VAL.COARSE field respectively.
Table 35-14. Digital Frequency Locked Loop Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Output frequency(2) 20 150 MHz
fREF Reference frequency(2) 8 150 kHz
FINE resolution step FINE > 100, all COARSE values (3) 0.38 %
Frequency drift over voltage
and temperature Open loop mode See Figure
35-4
Accuracy(2)
FINE lock, fREF = 32kHz, SSG disabled 0.1 0.5
%
ACCURATE lock, fREF = 32kHz, dither clk
RCSYS/2, SSG disabled 0.06 0.5
FINE lock, fREF = 8-150kHz, SSG
disabled 0.2 1
ACCURATE lock, fREF = 8-150kHz,
dither clk RCSYS/2, SSG disabled 0.1 1
IDFLL Power consumption 25 µA/MHz
tSTARTUP Startup time(2) Within 90% of final values 100 µs
tLOCK Lock time
fREF = 32kHz, FINE lock, SSG disabled 8
ms fREF = 32kHz, ACCURATE lock, dithering
clock = RCSYS/2, SSG disabled 28
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Figure 35-4. DFLL Open Loop Frequency Variation(1)(2)
Notes: 1. The plot shows a typical open loop mode behavior with COARSE= 99 and FINE= 255.
2. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.6.5 120MHz RC Oscillator (RC120M) Characteristics
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
DFLL Open Loop Frequency variation
80
90
100
110
120
130
140
150
160
-40 -20 0 20 40 60 80
Temperature
Frequencies (MHz)
1,98V
1,8V
1.62V
Table 35-15. Internal 120MHz RC Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Output frequency(1) 88 120 152 MHz
IRC120M Current consumption 1.2 mA
tSTARTUP Startup time(1) VVDDCORE = 1.8V 3 µs
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35.6.6 32kHz RC Oscillator (RC32K) Characteristics
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.6.7 System RC Oscillator (RCSYS) Characteristics
35.7 Flash Characteristics
Table 35-18 gives the device maximum operating frequency depending on the number of flash
wait states and the flash read mode. The FSW bit in the FLASHCDW FSR register controls the
number of wait states used when accessing the flash memory.
Table 35-16. 32kHz RC Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Output frequency(1) 20 32 44 kHz
IRC32K Current consumption 0.7 µA
tSTARTUP Startup time(1) 100 µs
Table 35-17. System RC Oscillator Characteristics
Symbol Parameter Conditions Min Typ Max Unit
fOUT Output frequency Calibrated at 85C 111.6 115 118.4 kHz
Table 35-18. Maximum Operating Frequency
Flash Wait States Read Mode Maximum Operating Frequency
1
High speed read mode
50MHz
0 25MHz
1
Normal read mode
30MHz
0 15MHz
Table 35-19. Flash Characteristics
Symbol Parameter Conditions Min Typ Max Unit
tFPP Page programming time
fCLK_HSB = 50MHz
5
ms
tFPE Page erase time 5
tFFP Fuse programming time 1
tFEA Full chip erase time (EA) 6
tFCE JTAG chip erase time (CHIP_ERASE) fCLK_HSB = 115kHz 310
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35.8 ABDACB Electrical Characteristics.
Notes: 1. Test Condition: Common Mode Offset Control disabled (CR.CMOC = 0). Alternative Upsampling Ratio disabled
(CR.ALTUPR = 0). Volume at maximum level (VCR0.VOLUME = 0x7FFF and VCR1.VOLUME = 0x7FFF). Device is battery
powered (9V) through an LDO, VDDIO at 3.3V. Analog low pass filter as shown in Figure 35-5(1. order differential low pass
filter followed by a 4. order low-pass), +VCC at +9V and -VCC at -9V. Test signal stored on a SD card and read by the SPI
Interface.
2. Performance numbers for dynamic range, SNR, and THD performance are very dependent on the application and circuit
board design. Since the design has 0dB Power Supply Rejection Ratio (PSRR), noise on the IO power supply will couple
directly through to the output and be present in the audio signal. To get the best performance one should reduce toggling of
other IO pins as much as possible and make sure the device has sufficient decoupling on the IO supply pins.
3. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Figure 35-5. Differential Analog Low-pass Filter
Table 35-20. Flash Endurance and Data Retention
Symbol Parameter Conditions Min Typ Max Unit
NFARRAY Array endurance (write/page) 100k
cycles
NFFUSE General Purpose fuses endurance (write/bit) 10k
tRET Data retention 15 years
Table 35-21. ABDACB Electrical Characteristics
Symbol Parameter Conditions MIN TYP MAX Unit
Resolution 16 Bits
Dynamic range(1)(2)(3) FS = 48.000kHz > 76 dB
SNR(1)(2)(3) FS = 48.000kHz > 46 dB
THD(1)(2)(3) FS = 48.000kHz < 0.02 %
PSRR 0 dB
VOut maximum CR.CMOC = 0 97/128 * VDDIO V
VOut minimum CR.CMOC = 0 31/128 * VDDIO V
Common mode
CR.CMOC = 0
CR.CMOC = 1, DAC_0 and DAC_1 pins
CR.CMOC = 1, DACN_0 and DACN_1 pins
64/128 * VDDIO
80/128 * VDDIO
48/128 * VDDIO
V
R1, 22K
C2
140p
R2, 22K
R4, 22K
C1, 140p
R3, 22K
R6, 22K
R5, 22K
R7, 22K
C4
270p
C3
310p
-Vcc
+Vcc
-Vcc
+Vcc
DAC
DACN
R8, 22K R9, 22K
C6
110p
C5
750p
-Vcc
+Vcc
GND GND GND GND GND
Out
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35.9 Analog Characteristics
35.9.1 Voltage Regulator Characteristics
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Note: 1. Refer to Section 6.1.2 on page 39.
Table 35-22. VREG Electrical Characteristics
Symbol Parameter Condition Min Typ Max Units
VVDDIN Input voltage range 1.98 3.3 3.6
V
VVDDCORE Output voltage, calibrated value VVDDIN >= 1.98V 1.8
Output voltage accuracy(1)
IOUT = 0.1mA to 60mA,
VVDDIN > 1.98V
2
%
IOUT = 0.1mA to 60mA,
VVDDIN <1.98V
4
IOUT DC output current(1)
Normal mode 60
mA
Low power mode 1
IVREG Static current of internal regulator
Normal mode 13
µA
Low power mode 4
Table 35-23. Decoupling Requirements
Symbol Parameter Condition Typ Techno. Units
CIN1 Input regulator capacitor 1 33
nF
CIN2 Input regulator capacitor 2 100
CIN3 Input regulator capacitor 3 10 µF
COUT1 Output regulator capacitor 1 100 nF
COUT2 Output regulator capacitor 2 2.2 Tantalum
0.5 3.0V, fADC = 6MHz,
12-bit resolution mode,
low impedance source
28
kSPS
VVDD > 3.0V, fADC = 6MHz,
10-bit resolution mode,
low impedance source
460
VVDD > 3.0V, fADC = 6MHz,
8-bit resolution mode,
low impedance source
460
VADVREFP Reference voltage range VADVREFP = VVDDANA 1.62 1.98 V
IADC Current consumption on VVDDANA ADC Clock = 6MHz 350
µA
IADVREFP
Current consumption on ADVREFP
pin fADC = 6MHz 150
Table 35-30. Analog Inputs
Symbol Parameter Conditions Min Typ Max Units
VADn Input Voltage Range
12-bit mode
10-bit mode 0 VADVREFP V
8-bit mode
CONCHIP Internal Capacitance(1) 22.5 pF
RONCHIP Internal Resistance(1)
VVDDIO = 3.0V to 3.6V,
VVDDCORE = 1.8V 3.15
kOhm
VVDDIO = VVDDCORE = 1.62V to 1.98V 55.9
RONCHIP CONCHIP RSOURCE
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( ) of the PCB and source must be taken into account when calculating the required
sample and hold time. Figure 35-8 shows the ADC input channel equivalent circuit.
Figure 35-8. ADC Input
The minimum sample and hold time (in ns) can be found using this formula:
Where n is the number of bits in the conversion. is defined by the SHTIM field in the
ADCIFB ACR register. Please refer to the ADCIFB chapter for more information.
35.9.6.2 Applicable Conditions and Derating Data
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
CSOURCE
ADCVREFP/2
CONCHIP
RONCHIP R Positive Input SOURCE
CSOURCE VIN
t
SAMPLEHOLD RONCHIP + RSOURCE CONCHIP CSOURCE + 2n + 1 ln
t
SAMPLEHOLD
Table 35-31. Transfer Characteristics 12-bit Resolution Mode(1)
Parameter Conditions Min Typ Max Units
Resolution 12 Bit
Integral non-linearity
ADC clock frequency = 6MHz,
Input Voltage Range = 0 - VADVREFP
+/-4
LSB
ADC clock frequency = 6MHz,
Input Voltage Range = (10% VADVREFP) -
(90% VADVREFP)
+/-2
Differential non-linearity
ADC clock frequency = 6MHz
-1.5 1.5
Offset error +/-3
Gain error +/-5
Table 35-32. Transfer Characteristics, 10-bit Resolution Mode(1)
Parameter Conditions Min Typ Max Units
Resolution 10 Bit
Integral non-linearity
ADC clock frequency = 6MHz
+/-1
LSB Differential non-linearity -1.0 1.0
Offset error +/-1
Gain error +/-2
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Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.9.7 Temperature Sensor Characteristics
Note: 1. The Temperature Sensor is not calibrated. The accuracy of the Temperature Sensor is governed by the ADC accuracy.
Table 35-33. Transfer Characteristics, 8-bit Resolution Mode(1)
Parameter Conditions Min Typ Max Units
Resolution 8 Bit
Integral non-linearity
ADC clock frequency = 6MHz
+/-0.5
LSB Differential non-linearity -0.3 0.3
Offset error +/-1
Gain error +/-1
Table 35-34. Temperature Sensor Characteristics(1)
Symbol Parameter Condition Min Typ Max Units
Gradient 1 mV/°C
ITS Current consumption 1 µA
tSTARTUP Startup time 0 µs
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35.9.8 Analog Comparator Characteristics
Notes: 1. AC.CONFn.FLEN and AC.CONFn.HYS fields, refer to the Analog Comparator Interface chapter.
2. Referring to fAC.
3. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.9.9 Capacitive Touch Characteristics
35.9.9.1 Discharge Current Source
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Table 35-35. Analog Comparator Characteristics
Symbol Parameter Condition Min Typ Max Units
Positive input
voltage range(3) -0.2 VVDDIO + 0.3
V
Negative input
voltage range(3) -0.2 VVDDIO - 0.6
Statistical offset(3)
VACREFN = 1.0V,
fAC = 12MHz,
filter length = 2,
hysteresis = 0(1)
20 mV
fAC
Clock frequency for
GCLK4(3) 12 MHz
Throughput rate(3) fAC = 12MHz 12 000 000 Comparisons
per second
Propagation delay
Delay from input
change to
Interrupt Status
Register Changes
ns
IAC
Current
consumption(3)
All channels,
VDDIO = 3.3V,
fA = 3MHz
420 µA
tSTARTUP Startup time 3 cycles
Input current per
pin(3) 0.2 µA/MHz(2)
Table 35-36. DICS Characteristics
Symbol Parameter Min Typ Max Unit
RREF Internal resistor 170 kOhm
k Trim step size(1) 0.7 %
1
t
CLKACIFB f
AC ---------------------------------------- + 3 t
CLKACIFB
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35.9.9.2 Strong Pull-up Pull-down
35.9.10 USB Transceiver Characteristics
The USB on-chip buffers comply with the Universal Serial Bus (USB) v2.0 standard. All AC
parameters related to these buffers can be found within the USB 2.0 electrical specifications.
35.9.10.1 Electrical Characteristics
Table 35-37. Strong Pull-up Pull-down
Parameter Min Typ Max Unit
Pull-down resistor 1
kOhm
Pull-up resistor 1
Table 35-38. Electrical Parameters
Symbol Parameter Conditions Min Typ Max Unit
REXT
Recommended external USB
series resistor
In series with each USB pin with
±5% 39 Ohm
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35.10 Timing Characteristics
35.10.1 Startup, Reset, and Wake-up Timing
The startup, reset, and wake-up timings are calculated using the following formula:
Where and are found in Table 35-39. is the period of the CPU clock. If a
clock source other than RCSYS is selected as the CPU clock, the oscillator startup time,
, must be added to the wake-up time from the stop, deepstop, and static sleep
modes. Please refer to the source for the CPU clock in the ”Oscillator Characteristics” on page
905 for more details about oscillator startup times.
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
35.10.2 RESET_N Timing
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
t tCONST NCPU t
CPU = +
t
CONST NCPU t
CPU
t
OSCSTART
Table 35-39. Maximum Reset and Wake-up Timing(1)
Parameter Measuring Max (in µs) Max
Startup time from power-up, using
regulator
Time from VDDIN crossing the VPOT+ threshold of
POR33 to the first instruction entering the decode
stage of CPU. VDDCORE is supplied by the internal
regulator.
2210 0
Startup time from power-up, no
regulator
Time from VDDIN crossing the VPOT+ threshold of
POR33 to the first instruction entering the decode
stage of CPU. VDDCORE is connected to VDDIN.
1810 0
Startup time from reset release
Time from releasing a reset source (except POR18,
POR33, and SM33) to the first instruction entering
the decode stage of CPU.
170 0
Wake-up
Idle
From wake-up event to the first instruction of an
interrupt routine entering the decode stage of the
CPU.
0 19
Frozen 0 110
Standby 0 110
Stop 27 + 116
Deepstop 27 + 116
Static 97 + 116
Wake-up from shutdown From wake-up event to the first instruction entering
the decode stage of the CPU. 1180 0
t
CONST NCPU
t
OSCSTART
t
OSCSTART
t
OSCSTART
Table 35-40. RESET_N Waveform Parameters(1)
Symbol Parameter Conditions Min Max Units
tRESET RESET_N minimum pulse length 10 ns
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35.10.3 USART in SPI Mode Timing
35.10.3.1 Master mode
Figure 35-9. USART in SPI Master Mode with (CPOL= CPHA= 0) or (CPOL= CPHA= 1)
Figure 35-10. USART in SPI Master Mode with (CPOL= 0 and CPHA= 1) or (CPOL= 1 and
CPHA= 0)
Notes: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
2. Where:
USPI0 USPI1
MISO
SPCK
MOSI
USPI2
USPI3 USPI4
MISO
SPCK
MOSI
USPI5
Table 35-41. USART in SPI Mode Timing, Master Mode(1)
Symbol Parameter Conditions Min Max Units
USPI0 MISO setup time before SPCK rises
VVDDIO from
3.0V to 3.6V,
maximum
external
capacitor =
40pF
28.7 + tSAMPLE(2)
ns
USPI1 MISO hold time after SPCK rises 0
USPI2 SPCK rising to MOSI delay 16.5
USPI3 MISO setup time before SPCK falls 25.8 + tSAMPLE(2)
USPI4 MISO hold time after SPCK falls 0
USPI5 SPCK falling to MOSI delay 21.19
t
SAMPLE t
SPCK
t
SPCK
2 t
CLKUSART ------------------------------------ 1
2
-- t
CLKUSART = –
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Maximum SPI Frequency, Master Output
The maximum SPI master output frequency is given by the following formula:
Where is the MOSI delay, USPI2 or USPI5 depending on CPOL and NCPHA. is
the maximum frequency of the SPI pins. Please refer to the I/O Pin Characteristics section for
the maximum frequency of the pins. is the maximum frequency of the CLK_SPI. Refer
to the SPI chapter for a description of this clock.
Maximum SPI Frequency, Master Input
The maximum SPI master input frequency is given by the following formula:
Where is the MISO setup and hold time, USPI0 + USPI1 or USPI3 + USPI4 depending on
CPOL and NCPHA. is the SPI slave response time. Please refer to the SPI slave
datasheet for . is the maximum frequency of the CLK_SPI. Refer to the SPI chapter
for a description of this clock.
35.10.3.2 Slave mode
Figure 35-11. USART in SPI Slave Mode with (CPOL= 0 and CPHA= 1) or (CPOL= 1 and
CPHA= 0)
f
SPCKMAX MIN fPINMAX
1
SPIn
------------ f
CLKSPI 2
9 = (, ) ----------------------------
SPIn fPINMAX
f
CLKSPI
f
SPCKMAX MIN 1
SPIn tVALID + ----------------------------------- f
CLKSPI 2
9 = ( ,) -----------------------------
SPIn
TVALID
TVALID f
CLKSPI
USPI7 USPI8
MISO
SPCK
MOSI
USPI6
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Figure 35-12. USART in SPI Slave Mode with (CPOL= CPHA= 0) or (CPOL= CPHA= 1)
Figure 35-13. USART in SPI Slave Mode, NPCS Timing
Notes: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
2. Where:
USPI10 USPI11
MISO
SPCK
MOSI
USPI9
USPI14
USPI12
USPI15
USPI13
NSS
SPCK, CPOL=0
SPCK, CPOL=1
Table 35-42. USART in SPI mode Timing, Slave Mode(1)
Symbol Parameter Conditions Min Max Units
USPI6 SPCK falling to MISO delay
VVDDIO from
3.0V to 3.6V,
maximum
external
capacitor =
40pF
37.3
ns
USPI7 MOSI setup time before SPCK rises 2.6 + tSAMPLE(2) +
tCLK_USART
USPI8 MOSI hold time after SPCK rises 0
USPI9 SPCK rising to MISO delay 37.0
USPI10 MOSI setup time before SPCK falls 2.6 + tSAMPLE(2) +
tCLK_USART
USPI11 MOSI hold time after SPCK falls 0
USPI12 NSS setup time before SPCK rises 27.2
USPI13 NSS hold time after SPCK falls 0
USPI14 NSS setup time before SPCK falls 27.2
USPI15 NSS hold time after SPCK rises 0
t
SAMPLE t
SPCK
t
SPCK
2 tCLKUSART ------------------------------------ 1
2
+ -- t
CLKUSART = –
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Maximum SPI Frequency, Slave Input Mode
The maximum SPI slave input frequency is given by the following formula:
Where is the MOSI setup and hold time, USPI7 + USPI8 or USPI10 + USPI11 depending
on CPOL and NCPHA. is the maximum frequency of the CLK_SPI. Refer to the SPI
chapter for a description of this clock.
Maximum SPI Frequency, Slave Output Mode
The maximum SPI slave output frequency is given by the following formula:
Where is the MISO delay, USPI6 or USPI9 depending on CPOL and NCPHA. is
the SPI master setup time. Please refer to the SPI master datasheet for . is the
maximum frequency of the CLK_SPI. Refer to the SPI chapter for a description of this
clock. is the maximum frequency of the SPI pins. Please refer to the I/O Pin Characteristics
section for the maximum frequency of the pins.
35.10.4 SPI Timing
35.10.4.1 Master mode
Figure 35-14. SPI Master Mode with (CPOL= NCPHA= 0) or (CPOL= NCPHA= 1)
f
SPCKMAX MIN f
CLKSPI 2
9 ----------------------------- 1
SPIn = ( ,) ------------
SPIn
f
CLKSPI
f
SPCKMAX MIN f
CLKSPI 2
9 ---------------------------- f
PINMAX 1
SPIn tSETUP + = ( ,) ------------------------------------
SPIn TSETUP
TSETUP f
CLKSPI
f
PINMAX
SPI0 SPI1
MISO
SPCK
MOSI
SPI2
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Figure 35-15. SPI Master Mode with (CPOL= 0 and NCPHA= 1) or (CPOL= 1 and NCPHA= 0)
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Maximum SPI Frequency, Master Output
The maximum SPI master output frequency is given by the following formula:
Where is the MOSI delay, SPI2 or SPI5 depending on CPOL and NCPHA. is the
maximum frequency of the SPI pins. Please refer to the I/O Pin Characteristics section for the
maximum frequency of the pins.
Maximum SPI Frequency, Master Input
The maximum SPI master input frequency is given by the following formula:
Where is the MISO setup and hold time, SPI0 + SPI1 or SPI3 + SPI4 depending on
CPOL and NCPHA. is the SPI slave response time. Please refer to the SPI slave
datasheet for .
SPI3 SPI4
MISO
SPCK
MOSI
SPI5
Table 35-43. SPI Timing, Master Mode(1)
Symbol Parameter Conditions Min Max Units
SPI0 MISO setup time before SPCK rises
VVDDIO from
3.0V to 3.6V,
maximum
external
capacitor =
40pF
33.4 + (tCLK_SPI)/2
ns
SPI1 MISO hold time after SPCK rises 0
SPI2 SPCK rising to MOSI delay 7.1
SPI3 MISO setup time before SPCK falls 29.2 + (tCLK_SPI)/2
SPI4 MISO hold time after SPCK falls 0
SPI5 SPCK falling to MOSI delay 8.63
f
SPCKMAX MIN fPINMAX
1
SPIn = ( ,) ------------
SPIn f
PINMAX
f
SPCKMAX
1
SPIn tVALID + = -----------------------------------
SPIn
t
VALID
tVALID
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35.10.4.2 Slave mode
Figure 35-16. SPI Slave Mode with (CPOL= 0 and NCPHA= 1) or (CPOL= 1 and NCPHA= 0)
Figure 35-17. SPI Slave Mode with (CPOL= NCPHA= 0) or (CPOL= NCPHA= 1)
Figure 35-18. SPI Slave Mode, NPCS Timing
SPI7 SPI8
MISO
SPCK
MOSI
SPI6
SPI10 SPI11
MISO
SPCK
MOSI
SPI9
SPI14
SPI12
SPI15
SPI13
NPCS
SPCK, CPOL=0
SPCK, CPOL=1
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Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
Maximum SPI Frequency, Slave Input Mode
The maximum SPI slave input frequency is given by the following formula:
Where is the MOSI setup and hold time, SPI7 + SPI8 or SPI10 + SPI11 depending on
CPOL and NCPHA. is the maximum frequency of the CLK_SPI. Refer to the SPI chapter
for a description of this clock.
Maximum SPI Frequency, Slave Output Mode
The maximum SPI slave output frequency is given by the following formula:
Where is the MISO delay, SPI6 or SPI9 depending on CPOL and NCPHA. is the
SPI master setup time. Please refer to the SPI master datasheet for . is the maximum
frequency of the SPI pins. Please refer to the I/O Pin Characteristics section for the
maximum frequency of the pins.
35.10.5 TWIM/TWIS Timing
Figure 35-45 shows the TWI-bus timing requirements and the compliance of the device with
them. Some of these requirements (tr
and tf
) are met by the device without requiring user intervention.
Compliance with the other requirements (tHD-STA, tSU-STA, tSU-STO, tHD-DAT, tSU-DAT-TWI, tLOWTWI,
tHIGH, and fTWCK) requires user intervention through appropriate programming of the relevant
Table 35-44. SPI Timing, Slave Mode(1)
Symbol Parameter Conditions Min Max Units
SPI6 SPCK falling to MISO delay
VVDDIO from
3.0V to 3.6V,
maximum
external
capacitor =
40pF
29.4
ns
SPI7 MOSI setup time before SPCK rises 0
SPI8 MOSI hold time after SPCK rises 6.0
SPI9 SPCK rising to MISO delay 29.0
SPI10 MOSI setup time before SPCK falls 0
SPI11 MOSI hold time after SPCK falls 5.5
SPI12 NPCS setup time before SPCK rises 3.4
SPI13 NPCS hold time after SPCK falls 1.1
SPI14 NPCS setup time before SPCK falls 3.3
SPI15 NPCS hold time after SPCK rises 0.7
f
SPCKMAX MIN fCLKSPI
1
SPIn = ( ,) ------------
SPIn
f
CLKSPI
f
SPCKMAX MIN fPINMAX
1
SPIn tSETUP + = (, ) ------------------------------------
SPIn t
SETUP
t
SETUP fPINMAX
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TWIM and TWIS user interface registers. Please refer to the TWIM and TWIS sections for more
information.
Notes: 1. Standard mode: ; fast mode: .
2. A device must internally provide a hold time of at least 300 ns for TWD with reference to the falling edge of TWCK.
Notations:
Cb = total capacitance of one bus line in pF
tclkpb = period of TWI peripheral bus clock
tprescaled = period of TWI internal prescaled clock (see chapters on TWIM and TWIS)
The maximum tHD;DAT has only to be met if the device does not stretch the LOW period (tLOW-TWI)
of TWCK.
Table 35-45. TWI-Bus Timing Requirements
Symbol Parameter Mode
Minimum Maximum Uni
Requirement Device Requirement Device t
tr TWCK and TWD rise time
Standard(
1) - 1000
ns
Fast(1) 20 + 0.1Cb 300
tf TWCK and TWD fall time
Standard - 300
ns
Fast 20 + 0.1Cb 300
tHD-STA (Repeated) START hold time
Standard 4
tclkpb - s
Fast 0.6
tSU-STA
(Repeated) START set-up
time
Standard 4.7
tclkpb - s
Fast 0.6
tSU-STO STOP set-up time
Standard 4.0
4tclkpb - s
Fast 0.6
tHD-DAT Data hold time
Standard
0.3(2) 2tclkpb
3.45()
15tprescaled +
tclkpb
s
Fast 0.9()
tSU-DATTWI
Data set-up time
Standard 250
2tclkpb - ns
Fast 100
tSU-DAT - -tclkpb - -
tLOW-TWI TWCK LOW period
Standard 4.7
4tclkpb - s
Fast 1.3
tLOW - -tclkpb - -
tHIGH TWCK HIGH period
Standard 4.0
8tclkpb - s
Fast 0.6
fTWCK TWCK frequency
Standard - 100
kHz
Fast 400
1
12tclkpb
-----------------------
fTWCK 100 kHz f
TWCK 100 kHz
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35.10.6 JTAG Timing
Figure 35-19. JTAG Interface Signals
Note: 1. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same process
technology. These values are not covered by test limits in production.
JTAG2
JTAG3
JTAG1
JTAG4
JTAG0
TMS/TDI
TCK
TDO
JTAG5
JTAG6
JTAG7 JTAG8
JTAG9
JTAG10
Boundary
Scan Inputs
Boundary
Scan Outputs
Table 35-46. JTAG Timings(1)
Symbol Parameter Conditions Min Max Units
JTAG0 TCK Low Half-period
VVDDIO from
3.0V to 3.6V,
maximum
external
capacitor =
40pF
21.8
ns
JTAG1 TCK High Half-period 8.6
JTAG2 TCK Period 30.3
JTAG3 TDI, TMS Setup before TCK High 2.0
JTAG4 TDI, TMS Hold after TCK High 2.3
JTAG5 TDO Hold Time 9.5
JTAG6 TCK Low to TDO Valid 21.8
JTAG7 Boundary Scan Inputs Setup Time 0.6
JTAG8 Boundary Scan Inputs Hold Time 6.9
JTAG9 Boundary Scan Outputs Hold Time 9.3
JTAG10 TCK to Boundary Scan Outputs Valid 32.2
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36. Mechanical Characteristics
36.1 Thermal Considerations
36.1.1 Thermal Data
Table 36-1 summarizes the thermal resistance data depending on the package.
36.1.2 Junction Temperature
The average chip-junction temperature, TJ, in °C can be obtained from the following:
1.
2.
where:
• JA = package thermal resistance, Junction-to-ambient (°C/W), provided in Table 36-1.
• JC = package thermal resistance, Junction-to-case thermal resistance (°C/W), provided in
Table 36-1.
• HEAT SINK = cooling device thermal resistance (°C/W), provided in the device datasheet.
• PD = device power consumption (W) estimated from data provided in Section 35.4 on page
898.
• TA = ambient temperature (°C).
From the first equation, the user can derive the estimated lifetime of the chip and decide if a
cooling device is necessary or not. If a cooling device is to be fitted on the chip, the second
equation should be used to compute the resulting average chip-junction temperature TJ in °C.
Table 36-1. Thermal Resistance Data
Symbol Parameter Condition Package Typ Unit
JA Junction-to-ambient thermal resistance Still Air TQFP48 54.4 C/W
JC Junction-to-case thermal resistance TQFP48 15.7
JA Junction-to-ambient thermal resistance Still Air QFN48 26.0 C/W
JC Junction-to-case thermal resistance QFN48 1.6
JA Junction-to-ambient thermal resistance Still Air TLLGA48 25.4 C/W
JC Junction-to-case thermal resistance TLLGA48 12.7
JA Junction-to-ambient thermal resistance Still Air TQFP64 52.9 C/W
JC Junction-to-case thermal resistance TQFP64 15.5
JA Junction-to-ambient thermal resistance Still Air QFN64 22.9 C/W
JC Junction-to-case thermal resistance QFN64 1.6
TJ TA PD JA = +
TJ TA PD HEATSINK JC = + +
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36.2 Package Drawings
Figure 36-1. TQFP-48 Package Drawing
Table 36-2. Device and Package Maximum Weight
140 mg
Table 36-3. Package Characteristics
Moisture Sensitivity Level MSL3
Table 36-4. Package Reference
JEDEC Drawing Reference MS-026
JESD97 Classification E3
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Figure 36-2. QFN-48 Package Drawing
Note: The exposed pad is not connected to anything internally, but should be soldered to ground to increase board level reliability.
Table 36-5. Device and Package Maximum Weight
140 mg
Table 36-6. Package Characteristics
Moisture Sensitivity Level MSL3
Table 36-7. Package Reference
JEDEC Drawing Reference M0-220
JESD97 Classification E3
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Figure 36-3. TLLGA-48 Package Drawing
Table 36-8. Device and Package Maximum Weight
39.3 mg
Table 36-9. Package Characteristics
Moisture Sensitivity Level MSL3
Table 36-10. Package Reference
JEDEC Drawing Reference N/A
JESD97 Classification E4
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Figure 36-4. TQFP-64 Package Drawing
Table 36-11. Device and Package Maximum Weight
300 mg
Table 36-12. Package Characteristics
Moisture Sensitivity Level MSL3
Table 36-13. Package Reference
JEDEC Drawing Reference MS-026
JESD97 Classification E3
936
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Figure 36-5. QFN-64 Package Drawing
Note: The exposed pad is not connected to anything internally, but should be soldered to ground to increase board level reliability.
Table 36-14. Device and Package Maximum Weight
200 mg
Table 36-15. Package Characteristics
Moisture Sensitivity Level MSL3
Table 36-16. Package Reference
JEDEC Drawing Reference M0-220
JESD97 Classification E3
937
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36.3 Soldering Profile
Table 36-17 gives the recommended soldering profile from J-STD-20.
A maximum of three reflow passes is allowed per component.
Table 36-17. Soldering Profile
Profile Feature Green Package
Average Ramp-up Rate (217°C to Peak) 3°C/s max
Preheat Temperature 175°C ±25°C 150-200°C
Time Maintained Above 217°C 60-150 s
Time within 5C of Actual Peak Temperature 30 s
Peak Temperature Range 260°C
Ramp-down Rate 6°C/s max
Time 25C to Peak Temperature 8 minutes max
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37. Ordering Information
Table 37-1. Ordering Information
Device Ordering Code Carrier Type Package Package Type
Temperature Operating
Range
ATUC256L3U
ATUC256L3U-AUTES ES
TQFP 64
JESD97 Classification E3
N/A
ATUC256L3U-AUT Tray
Industrial (-40C to 85C)
ATUC256L3U-AUR Tape & Reel
ATUC256L3U-Z3UTES ES
QFN 64
N/A
ATUC256L3U-Z3UT Tray
Industrial (-40C to 85C)
ATUC256L3U-Z3UR Tape & Reel
ATUC128L3U
ATUC128L3U-AUT Tray TQFP 64
JESD97 Classification E3 Industrial (-40C to 85C)
ATUC128L3U-AUR Tape & Reel
ATUC128L3U-Z3UT Tray QFN 64
ATUC128L3U-Z3UR Tape & Reel
ATUC64L3U
ATUC64L3U-AUT Tray TQFP 64
JESD97 Classification E3 Industrial (-40C to 85C) ATUC64L3U-AUR Tape & Reel
ATUC64L3U-Z3UT Tray QFN 64
ATUC64L3U-Z3UR Tape & Reel
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ATUC256L4U
ATUC256L4U-AUTES ES
TQFP 48
JESD97 Classification E3
N/A
ATUC256L4U-AUT Tray Industrial (-40C to 85C)
ATUC256L4U-AUR Tape & Reel
ATUC256L4U-ZAUTES ES
QFN 48
N/A
ATUC256L4U-ZAUT Tray
Industrial (-40C to 85C) ATUC256L4U-ZAUR Tape & Reel
ATUC256L4U-D3HES ES
TLLGA 48 JESD97 Classification E4
N/A
ATUC256L4U-D3HT Tray
Industrial (-40C to 85C)
ATUC256L4U-D3HR Tape & Reel
ATUC128L4U
ATUC128L4U-AUT Tray TQFP 48
JESD97 Classification E3
ATUC128L4U-AUR Tape & Reel
ATUC128L4U-ZAUT Tray QFN 48
ATUC128L4U-ZAUR Tape & Reel
ATUC128L4U-D3HT Tray TLLGA 48 JESD97 Classification E4
ATUC128L4U-D3HR Tape & Reel
ATUC64L4U
ATUC64L4U-AUT Tray TQFP 48
JESD97 Classification E3
ATUC64L4U-AUR Tape & Reel
ATUC64L4U-ZAUT Tray QFN 48
ATUC64L4U-ZAUR Tape & Reel
ATUC64L4U-D3HT Tray TLLGA 48 JESD97 Classification E4
ATUC64L4U-D3HR Tape & Reel
Table 37-1. Ordering Information
Device Ordering Code Carrier Type Package Package Type
Temperature Operating
Range
940
32142D–06/2013
ATUC64/128/256L3/4U
38. Errata
38.1 Rev. C
38.1.1 SCIF
1. The RC32K output on PA20 is not always permanently disabled
The RC32K output on PA20 may sometimes re-appear.
Fix/Workaround
Before using RC32K for other purposes, the following procedure has to be followed in order
to properly disable it:
- Run the CPU on RCSYS
- Disable the output to PA20 by writing a zero to PM.PPCR.RC32OUT
- Enable RC32K by writing a one to SCIF.RC32KCR.EN, and wait for this bit to be read as
one
- Disable RC32K by writing a zero to SCIF.RC32KCR.EN, and wait for this bit to be read as
zero.
2. PLLCOUNT value larger than zero can cause PLLEN glitch
Initializing the PLLCOUNT with a value greater than zero creates a glitch on the PLLEN signal
during asynchronous wake up.
Fix/Workaround
The lock-masking mechanism for the PLL should not be used.
The PLLCOUNT field of the PLL Control Register should always be written to zero.
3. Writing 0x5A5A5A5A to the SCIF memory range will enable the SCIF UNLOCK feature
The SCIF UNLOCK feature will be enabled if the value 0x5A5A5A5A is written to any location
in the SCIF memory range.
Fix/Workaround
None.
38.1.2 SPI
1. SPI data transfer hangs with CSR0.CSAAT==1 and MR.MODFDIS==0
When CSR0.CSAAT==1 and mode fault detection is enabled (MR.MODFDIS==0), the SPI
module will not start a data transfer.
Fix/Workaround
Disable mode fault detection by writing a one to MR.MODFDIS.
2. Disabling SPI has no effect on the SR.TDRE bit
Disabling SPI has no effect on the SR.TDRE bit whereas the write data command is filtered
when SPI is disabled. Writing to TDR when SPI is disabled will not clear SR.TDRE. If SPI is
disabled during a PDCA transfer, the PDCA will continue to write data to TDR until its buffer
is empty, and this data will be lost.
Fix/Workaround
Disable the PDCA, add two NOPs, and disable the SPI. To continue the transfer, enable the
SPI and PDCA.
3. SPI disable does not work in SLAVE mode
SPI disable does not work in SLAVE mode.
Fix/Workaround
Read the last received data, then perform a software reset by writing a one to the Software
Reset bit in the Control Register (CR.SWRST).
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4. SPI bad serial clock generation on 2nd chip_select when SCBR=1, CPOL=1, and
NCPHA=0
When multiple chip selects (CS) are in use, if one of the baudrates equal 1 while one
(CSRn.SCBR=1) of the others do not equal 1, and CSRn.CPOL=1 and CSRn.NCPHA=0,
then an additional pulse will be generated on SCK.
Fix/Workaround
When multiple CS are in use, if one of the baudrates equals 1, the others must also equal 1
if CSRn.CPOL=1 and CSRn.NCPHA=0.
5. SPI mode fault detection enable causes incorrect behavior
When mode fault detection is enabled (MR.MODFDIS==0), the SPI module may not operate
properly.
Fix/Workaround
Always disable mode fault detection before using the SPI by writing a one to MR.MODFDIS.
6. SPI RDR.PCS is not correct
The PCS (Peripheral Chip Select) field in the SPI RDR (Receive Data Register) does not
correctly indicate the value on the NPCS pins at the end of a transfer.
Fix/Workaround
Do not use the PCS field of the SPI RDR.
38.1.3 TWI
1. SMBALERT bit may be set after reset
The SMBus Alert (SMBALERT) bit in the Status Register (SR) might be erroneously set after
system reset.
Fix/Workaround
After system reset, clear the SR.SMBALERT bit before commencing any TWI transfer.
2. Clearing the NAK bit before the BTF bit is set locks up the TWI bus
When the TWIS is in transmit mode, clearing the NAK Received (NAK) bit of the Status Register
(SR) before the end of the Acknowledge/Not Acknowledge cycle will cause the TWIS to
attempt to continue transmitting data, thus locking up the bus.
Fix/Workaround
Clear SR.NAK only after the Byte Transfer Finished (BTF) bit of the same register has been
set.
38.1.4 TC
1. Channel chaining skips first pulse for upper channel
When chaining two channels using the Block Mode Register, the first pulse of the clock
between the channels is skipped.
Fix/Workaround
Configure the lower channel with RA = 0x1 and RC = 0x2 to produce a dummy clock cycle
for the upper channel. After the dummy cycle has been generated, indicated by the
SR.CPCS bit, reconfigure the RA and RC registers for the lower channel with the real
values.
38.1.5 CAT
1. CAT QMatrix sense capacitors discharged prematurely
At the end of a QMatrix burst charging sequence that uses different burst count values for
different Y lines, the Y lines may be incorrectly grounded for up to n-1 periods of the periph-
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eral bus clock, where n is the ratio of the PB clock frequency to the GCLK_CAT frequency.
This results in premature loss of charge from the sense capacitors and thus increased variability
of the acquired count values.
Fix/Workaround
Enable the 1kOhm drive resistors on all implemented QMatrix Y lines (CSA 1, 3, 5, 7, 9, 11,
13, and/or 15) by writing ones to the corresponding odd bits of the CSARES register.
2. Autonomous CAT acquisition must be longer than AST source clock period
When using the AST to trigger CAT autonomous touch acquisition in sleep modes where the
CAT bus clock is turned off, the CAT will start several acquisitions if the period of the AST
source clock is larger than one CAT acquisition. One AST clock period after the AST trigger,
the CAT clock will automatically stop and the CAT acquisition can be stopped prematurely,
ruining the result.
Fix/Workaround
Always ensure that the ATCFG1.max field is set so that the duration of the autonomous
touch acquisition is greater than one clock period of the AST source clock.
38.1.6 aWire
1. aWire MEMORY_SPEED_REQUEST command does not return correct CV
The aWire MEMORY_SPEED_REQUEST command does not return a CV corresponding to
the formula in the aWire Debug Interface chapter.
Fix/Workaround
Issue a dummy read to address 0x100000000 before issuing the
MEMORY_SPEED_REQUEST command and use this formula instead:
38.2 Flash
1. Corrupted data in flash may happen after flash page write operations
After a flash page write operation from an external programmer, reading (data read or code
fetch) in flash may fail. This may lead to an exception or to others errors derived from this
corrupted read access.
Fix/Workaround
Before any flash page write operation, each write in the page buffer must preceded by a
write in the page buffer with 0xFFFF_FFFF content at any address in the page.
38.3 Rev. B
38.3.1 SCIF
1. The RC32K output on PA20 is not always permanently disabled
The RC32K output on PA20 may sometimes re-appear.
Fix/Workaround
Before using RC32K for other purposes, the following procedure has to be followed in order
to properly disable it:
- Run the CPU on RCSYS
- Disable the output to PA20 by writing a zero to PM.PPCR.RC32OUT
- Enable RC32K by writing a one to SCIF.RC32KCR.EN, and wait for this bit to be read as
one
f
sab
7f
aw
CV – 3 = ----------------
943
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- Disable RC32K by writing a zero to SCIF.RC32KCR.EN, and wait for this bit to be read as
zero.
2. PLLCOUNT value larger than zero can cause PLLEN glitch
Initializing the PLLCOUNT with a value greater than zero creates a glitch on the PLLEN signal
during asynchronous wake up.
Fix/Workaround
The lock-masking mechanism for the PLL should not be used.
The PLLCOUNT field of the PLL Control Register should always be written to zero.
3. Writing 0x5A5A5A5A to the SCIF memory range will enable the SCIF UNLOCK feature
The SCIF UNLOCK feature will be enabled if the value 0x5A5A5A5A is written to any location
in the SCIF memory range.
Fix/Workaround
None.
38.3.2 WDT
1. WDT Control Register does not have synchronization feedback
When writing to the Timeout Prescale Select (PSEL), Time Ban Prescale Select (TBAN),
Enable (EN), or WDT Mode (MODE) fieldss of the WDT Control Register (CTRL), a synchronizer
is started to propagate the values to the WDT clcok domain. This synchronization
takes a finite amount of time, but only the status of the synchronization of the EN bit is
reflected back to the user. Writing to the synchronized fields during synchronization can lead
to undefined behavior.
Fix/Workaround
-When writing to the affected fields, the user must ensure a wait corresponding to 2 clock
cycles of both the WDT peripheral bus clock and the selected WDT clock source.
-When doing writes that changes the EN bit, the EN bit can be read back until it reflects the
written value.
38.3.3 SPI
1. SPI data transfer hangs with CSR0.CSAAT==1 and MR.MODFDIS==0
When CSR0.CSAAT==1 and mode fault detection is enabled (MR.MODFDIS==0), the SPI
module will not start a data transfer.
Fix/Workaround
Disable mode fault detection by writing a one to MR.MODFDIS.
2. Disabling SPI has no effect on the SR.TDRE bit
Disabling SPI has no effect on the SR.TDRE bit whereas the write data command is filtered
when SPI is disabled. Writing to TDR when SPI is disabled will not clear SR.TDRE. If SPI is
disabled during a PDCA transfer, the PDCA will continue to write data to TDR until its buffer
is empty, and this data will be lost.
Fix/Workaround
Disable the PDCA, add two NOPs, and disable the SPI. To continue the transfer, enable the
SPI and PDCA.
3. SPI disable does not work in SLAVE mode
SPI disable does not work in SLAVE mode.
Fix/Workaround
Read the last received data, then perform a software reset by writing a one to the Software
Reset bit in the Control Register (CR.SWRST).
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4. SPI bad serial clock generation on 2nd chip_select when SCBR=1, CPOL=1, and
NCPHA=0
When multiple chip selects (CS) are in use, if one of the baudrates equal 1 while one
(CSRn.SCBR=1) of the others do not equal 1, and CSRn.CPOL=1 and CSRn.NCPHA=0,
then an additional pulse will be generated on SCK.
Fix/Workaround
When multiple CS are in use, if one of the baudrates equals 1, the others must also equal 1
if CSRn.CPOL=1 and CSRn.NCPHA=0.
5. SPI mode fault detection enable causes incorrect behavior
When mode fault detection is enabled (MR.MODFDIS==0), the SPI module may not operate
properly.
Fix/Workaround
Always disable mode fault detection before using the SPI by writing a one to MR.MODFDIS.
6. SPI RDR.PCS is not correct
The PCS (Peripheral Chip Select) field in the SPI RDR (Receive Data Register) does not
correctly indicate the value on the NPCS pins at the end of a transfer.
Fix/Workaround
Do not use the PCS field of the SPI RDR.
38.3.4 TWI
1. TWIS may not wake the device from sleep mode
If the CPU is put to a sleep mode (except Idle and Frozen) directly after a TWI Start condition,
the CPU may not wake upon a TWIS address match. The request is NACKed.
Fix/Workaround
When using the TWI address match to wake the device from sleep, do not switch to sleep
modes deeper than Frozen. Another solution is to enable asynchronous EIC wake on the
TWIS clock (TWCK) or TWIS data (TWD) pins, in order to wake the system up on bus
events.
2. SMBALERT bit may be set after reset
The SMBus Alert (SMBALERT) bit in the Status Register (SR) might be erroneously set after
system reset.
Fix/Workaround
After system reset, clear the SR.SMBALERT bit before commencing any TWI transfer.
3. Clearing the NAK bit before the BTF bit is set locks up the TWI bus
When the TWIS is in transmit mode, clearing the NAK Received (NAK) bit of the Status Register
(SR) before the end of the Acknowledge/Not Acknowledge cycle will cause the TWIS to
attempt to continue transmitting data, thus locking up the bus.
Fix/Workaround
Clear SR.NAK only after the Byte Transfer Finished (BTF) bit of the same register has been
set.
38.3.5 PWMA
1. The SR.READY bit cannot be cleared by writing to SCR.READY
The Ready bit in the Status Register will not be cleared when writing a one to the corresponding
bit in the Status Clear register. The Ready bit will be cleared when the Busy bit is
set.
Fix/Workaround
945
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Disable the Ready interrupt in the interrupt handler when receiving the interrupt. When an
operation that triggers the Busy/Ready bit is started, wait until the ready bit is low in the Status
Register before enabling the interrupt.
38.3.6 TC
1. Channel chaining skips first pulse for upper channel
When chaining two channels using the Block Mode Register, the first pulse of the clock
between the channels is skipped.
Fix/Workaround
Configure the lower channel with RA = 0x1 and RC = 0x2 to produce a dummy clock cycle
for the upper channel. After the dummy cycle has been generated, indicated by the
SR.CPCS bit, reconfigure the RA and RC registers for the lower channel with the real
values.
38.3.7 CAT
1. CAT QMatrix sense capacitors discharged prematurely
At the end of a QMatrix burst charging sequence that uses different burst count values for
different Y lines, the Y lines may be incorrectly grounded for up to n-1 periods of the peripheral
bus clock, where n is the ratio of the PB clock frequency to the GCLK_CAT frequency.
This results in premature loss of charge from the sense capacitors and thus increased variability
of the acquired count values.
Fix/Workaround
Enable the 1kOhm drive resistors on all implemented QMatrix Y lines (CSA 1, 3, 5, 7, 9, 11,
13, and/or 15) by writing ones to the corresponding odd bits of the CSARES register.
2. Autonomous CAT acquisition must be longer than AST source clock period
When using the AST to trigger CAT autonomous touch acquisition in sleep modes where the
CAT bus clock is turned off, the CAT will start several acquisitions if the period of the AST
source clock is larger than one CAT acquisition. One AST clock period after the AST trigger,
the CAT clock will automatically stop and the CAT acquisition can be stopped prematurely,
ruining the result.
Fix/Workaround
Always ensure that the ATCFG1.max field is set so that the duration of the autonomous
touch acquisition is greater than one clock period of the AST source clock.
3. CAT consumes unnecessary power when disabled or when autonomous touch not
used
A CAT prescaler controlled by the ATCFG0.DIV field will be active even when the CAT module
is disabled or when the autonomous touch feature is not used, thereby causing
unnecessary power consumption.
Fix/Workaround
If the CAT module is not used, disable the CLK_CAT clock in the PM module. If the CAT
module is used but the autonomous touch feature is not used, the power consumption of the
CAT module may be reduced by writing 0xFFFF to the ATCFG0.DIV field.
38.3.8 aWire
1. aWire MEMORY_SPEED_REQUEST command does not return correct CV
The aWire MEMORY_SPEED_REQUEST command does not return a CV corresponding to
the formula in the aWire Debug Interface chapter.
Fix/Workaround
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Issue a dummy read to address 0x100000000 before issuing the
MEMORY_SPEED_REQUEST command and use this formula instead:
38.4 Flash
2. Corrupted data in flash may happen after flash page write operations
After a flash page write operation from an external programmer, reading (data read or code
fetch) in flash may fail. This may lead to an exception or to others errors derived from this
corrupted read access.
Fix/Workaround
Before any flash page write operation, each write in the page buffer must preceded by a
write in the page buffer with 0xFFFF_FFFF content at any address in the page.
38.5 Rev. A
38.5.1 Device
3. JTAGID is wrong
The JTAGID reads 0x021DF03F for all devices.
Fix/Workaround
None.
38.5.2 FLASHCDW
1. General-purpose fuse programming does not work
The general-purpose fuses cannot be programmed and are stuck at 1. Please refer to the
Fuse Settings chapter in the FLASHCDW for more information about what functions are
affected.
Fix/Workaround
None.
2. Set Security Bit command does not work
The Set Security Bit (SSB) command of the FLASHCDW does not work. The device cannot
be locked from external JTAG, aWire, or other debug accesses.
Fix/Workaround
None.
3. Flash programming time is longer than specified
f
sab
7f
aw
CV – 3 = ----------------
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The flash programming time is now:
Fix/Workaround
None.
4. Power Manager
5. Clock Failure Detector (CFD) can be issued while turning off the CFD
While turning off the CFD, the CFD bit in the Status Register (SR) can be set. This will
change the main clock source to RCSYS.
Fix/Workaround
Solution 1: Enable CFD interrupt. If CFD interrupt is issues after turning off the CFD, switch
back to original main clock source.
Solution 2: Only turn off the CFD while running the main clock on RCSYS.
6. Sleepwalking in idle and frozen sleep mode will mask all other PB clocks
If the CPU is in idle or frozen sleep mode and a module is in a state that triggers sleep walking,
all PB clocks will be masked except the PB clock to the sleepwalking module.
Fix/Workaround
Mask all clock requests in the PM.PPCR register before going into idle or frozen mode.
4. Unused PB clocks are running
Three unused PBA clocks are enabled by default and will cause increased active power
consumption.
Fix/Workaround
Disable the clocks by writing zeroes to bits [27:25] in the PBA clock mask register.
38.5.3 SCIF
1. The RC32K output on PA20 is not always permanently disabled
The RC32K output on PA20 may sometimes re-appear.
Fix/Workaround
Before using RC32K for other purposes, the following procedure has to be followed in order
to properly disable it:
- Run the CPU on RCSYS
- Disable the output to PA20 by writing a zero to PM.PPCR.RC32OUT
- Enable RC32K by writing a one to SCIF.RC32KCR.EN, and wait for this bit to be read as
one
- Disable RC32K by writing a zero to SCIF.RC32KCR.EN, and wait for this bit to be read as
zero.
2. PLL lock might not clear after disable
Table 38-1. Flash Characteristics
Symbol Parameter Conditions Min Typ Max Unit
TFPP Page programming time
fCLK_HSB= 50MHz
7.5
ms
TFPE Page erase time 7.5
TFFP Fuse programming time 1
TFEA Full chip erase time (EA) 9
TFCE
JTAG chip erase time
(CHIP_ERASE) fCLK_HSB= 115kHz 250
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Under certain circumstances, the lock signal from the Phase Locked Loop (PLL) oscillator
may not go back to zero after the PLL oscillator has been disabled. This can cause the propagation
of clock signals with the wrong frequency to parts of the system that use the PLL
clock.
Fix/Workaround
PLL must be turned off before entering STOP, DEEPSTOP or STATIC sleep modes. If PLL
has been turned off, a delay of 30us must be observed after the PLL has been enabled
again before the SCIF.PLL0LOCK bit can be used as a valid indication that the PLL is
locked.
3. PLLCOUNT value larger than zero can cause PLLEN glitch
Initializing the PLLCOUNT with a value greater than zero creates a glitch on the PLLEN signal
during asynchronous wake up.
Fix/Workaround
The lock-masking mechanism for the PLL should not be used.
The PLLCOUNT field of the PLL Control Register should always be written to zero.
4. RCSYS is not calibrated
The RCSYS is not calibrated and will run faster than 115.2kHz. Frequencies around 150kHz
can be expected.
Fix/Workaround
If a known clock source is available the RCSYS can be runtime calibrated by using the frequency
meter (FREQM) and tuning the RCSYS by writing to the RCCR register in SCIF.
5. Writing 0x5A5A5A5A to the SCIF memory range will enable the SCIF UNLOCK feature
The SCIF UNLOCK feature will be enabled if the value 0x5A5A5A5A is written to any location
in the SCIF memory range.
Fix/Workaround
None.
38.5.4 WDT
1. Clearing the Watchdog Timer (WDT) counter in second half of timeout period will
issue a Watchdog reset
If the WDT counter is cleared in the second half of the timeout period, the WDT will immediately
issue a Watchdog reset.
Fix/Workaround
Use twice as long timeout period as needed and clear the WDT counter within the first half
of the timeout period. If the WDT counter is cleared after the first half of the timeout period,
you will get a Watchdog reset immediately. If the WDT counter is not cleared at all, the time
before the reset will be twice as long as needed.
2. WDT Control Register does not have synchronization feedback
When writing to the Timeout Prescale Select (PSEL), Time Ban Prescale Select (TBAN),
Enable (EN), or WDT Mode (MODE) fieldss of the WDT Control Register (CTRL), a synchronizer
is started to propagate the values to the WDT clcok domain. This synchronization
takes a finite amount of time, but only the status of the synchronization of the EN bit is
reflected back to the user. Writing to the synchronized fields during synchronization can lead
to undefined behavior.
Fix/Workaround
-When writing to the affected fields, the user must ensure a wait corresponding to 2 clock
cycles of both the WDT peripheral bus clock and the selected WDT clock source.
-When doing writes that changes the EN bit, the EN bit can be read back until it reflects the
written value.
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38.5.5 GPIO
1. Clearing Interrupt flags can mask other interrupts
When clearing interrupt flags in a GPIO port, interrupts on other pins of that port, happening
in the same clock cycle will not be registered.
Fix/Workaround
Read the PVR register of the port before and after clearing the interrupt to see if any pin
change has happened while clearing the interrupt. If any change occurred in the PVR
between the reads, they must be treated as an interrupt.
38.5.6 SPI
1. SPI data transfer hangs with CSR0.CSAAT==1 and MR.MODFDIS==0
When CSR0.CSAAT==1 and mode fault detection is enabled (MR.MODFDIS==0), the SPI
module will not start a data transfer.
Fix/Workaround
Disable mode fault detection by writing a one to MR.MODFDIS.
2. Disabling SPI has no effect on the SR.TDRE bit
Disabling SPI has no effect on the SR.TDRE bit whereas the write data command is filtered
when SPI is disabled. Writing to TDR when SPI is disabled will not clear SR.TDRE. If SPI is
disabled during a PDCA transfer, the PDCA will continue to write data to TDR until its buffer
is empty, and this data will be lost.
Fix/Workaround
Disable the PDCA, add two NOPs, and disable the SPI. To continue the transfer, enable the
SPI and PDCA.
3. SPI disable does not work in SLAVE mode
SPI disable does not work in SLAVE mode.
Fix/Workaround
Read the last received data, then perform a software reset by writing a one to the Software
Reset bit in the Control Register (CR.SWRST).
4. SPI bad serial clock generation on 2nd chip_select when SCBR=1, CPOL=1, and
NCPHA=0
When multiple chip selects (CS) are in use, if one of the baudrates equal 1 while one
(CSRn.SCBR=1) of the others do not equal 1, and CSRn.CPOL=1 and CSRn.NCPHA=0,
then an additional pulse will be generated on SCK.
Fix/Workaround
When multiple CS are in use, if one of the baudrates equals 1, the others must also equal 1
if CSRn.CPOL=1 and CSRn.NCPHA=0.
5. SPI mode fault detection enable causes incorrect behavior
When mode fault detection is enabled (MR.MODFDIS==0), the SPI module may not operate
properly.
Fix/Workaround
Always disable mode fault detection before using the SPI by writing a one to MR.MODFDIS.
6. SPI RDR.PCS is not correct
The PCS (Peripheral Chip Select) field in the SPI RDR (Receive Data Register) does not
correctly indicate the value on the NPCS pins at the end of a transfer.
Fix/Workaround
Do not use the PCS field of the SPI RDR.
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38.5.7 TWI
1. TWIS may not wake the device from sleep mode
If the CPU is put to a sleep mode (except Idle and Frozen) directly after a TWI Start condition,
the CPU may not wake upon a TWIS address match. The request is NACKed.
Fix/Workaround
When using the TWI address match to wake the device from sleep, do not switch to sleep
modes deeper than Frozen. Another solution is to enable asynchronous EIC wake on the
TWIS clock (TWCK) or TWIS data (TWD) pins, in order to wake the system up on bus
events.
2. SMBALERT bit may be set after reset
The SMBus Alert (SMBALERT) bit in the Status Register (SR) might be erroneously set after
system reset.
Fix/Workaround
After system reset, clear the SR.SMBALERT bit before commencing any TWI transfer.
3. Clearing the NAK bit before the BTF bit is set locks up the TWI bus
When the TWIS is in transmit mode, clearing the NAK Received (NAK) bit of the Status Register
(SR) before the end of the Acknowledge/Not Acknowledge cycle will cause the TWIS to
attempt to continue transmitting data, thus locking up the bus.
Fix/Workaround
Clear SR.NAK only after the Byte Transfer Finished (BTF) bit of the same register has been
set.
4. TWIS stretch on Address match error
When the TWIS stretches TWCK due to a slave address match, it also holds TWD low for
the same duration if it is to be receiving data. When TWIS releases TWCK, it releases TWD
at the same time. This can cause a TWI timing violation.
Fix/Workaround
None.
5. TWIM TWALM polarity is wrong
The TWALM signal in the TWIM is active high instead of active low.
Fix/Workaround
Use an external inverter to invert the signal going into the TWIM. When using both TWIM
and TWIS on the same pins, the TWALM cannot be used.
38.5.8 PWMA
1. The SR.READY bit cannot be cleared by writing to SCR.READY
The Ready bit in the Status Register will not be cleared when writing a one to the corresponding
bit in the Status Clear register. The Ready bit will be cleared when the Busy bit is
set.
Fix/Workaround
Disable the Ready interrupt in the interrupt handler when receiving the interrupt. When an
operation that triggers the Busy/Ready bit is started, wait until the ready bit is low in the Status
Register before enabling the interrupt.
38.5.9 TC
1. Channel chaining skips first pulse for upper channel
When chaining two channels using the Block Mode Register, the first pulse of the clock
between the channels is skipped.
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Fix/Workaround
Configure the lower channel with RA = 0x1 and RC = 0x2 to produce a dummy clock cycle
for the upper channel. After the dummy cycle has been generated, indicated by the
SR.CPCS bit, reconfigure the RA and RC registers for the lower channel with the real
values.
38.5.10 ADCIFB
1. ADCIFB DMA transfer does not work with divided PBA clock
DMA requests from the ADCIFB will not be performed when the PBA clock is slower than
the HSB clock.
Fix/Workaround
Do not use divided PBA clock when the PDCA transfers from the ADCIFB.
38.5.11 CAT
1. CAT QMatrix sense capacitors discharged prematurely
At the end of a QMatrix burst charging sequence that uses different burst count values for
different Y lines, the Y lines may be incorrectly grounded for up to n-1 periods of the peripheral
bus clock, where n is the ratio of the PB clock frequency to the GCLK_CAT frequency.
This results in premature loss of charge from the sense capacitors and thus increased variability
of the acquired count values.
Fix/Workaround
Enable the 1kOhm drive resistors on all implemented QMatrix Y lines (CSA 1, 3, 5, 7, 9, 11,
13, and/or 15) by writing ones to the corresponding odd bits of the CSARES register.
2. Autonomous CAT acquisition must be longer than AST source clock period
When using the AST to trigger CAT autonomous touch acquisition in sleep modes where the
CAT bus clock is turned off, the CAT will start several acquisitions if the period of the AST
source clock is larger than one CAT acquisition. One AST clock period after the AST trigger,
the CAT clock will automatically stop and the CAT acquisition can be stopped prematurely,
ruining the result.
Fix/Workaround
Always ensure that the ATCFG1.max field is set so that the duration of the autonomous
touch acquisition is greater than one clock period of the AST source clock.
3. CAT consumes unnecessary power when disabled or when autonomous touch not
used
A CAT prescaler controlled by the ATCFG0.DIV field will be active even when the CAT module
is disabled or when the autonomous touch feature is not used, thereby causing
unnecessary power consumption.
Fix/Workaround
If the CAT module is not used, disable the CLK_CAT clock in the PM module. If the CAT
module is used but the autonomous touch feature is not used, the power consumption of the
CAT module may be reduced by writing 0xFFFF to the ATCFG0.DIV field.
4. CAT module does not terminate QTouch burst on detect
The CAT module does not terminate a QTouch burst when the detection voltage is
reached on the sense capacitor. This can cause the sense capacitor to be charged more
than necessary. Depending on the dielectric absorption characteristics of the capacitor, this
can lead to unstable measurements.
Fix/Workaround
Use the minimum possible value for the MAX field in the ATCFG1, TG0CFG1, and
TG1CFG1 registers.
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38.5.12 aWire
1. aWire MEMORY_SPEED_REQUEST command does not return correct CV
The aWire MEMORY_SPEED_REQUEST command does not return a CV corresponding to
the formula in the aWire Debug Interface chapter.
Fix/Workaround
Issue a dummy read to address 0x100000000 before issuing the
MEMORY_SPEED_REQUEST command and use this formula instead:
38.5.13 Flash
5. Corrupted data in flash may happen after flash page write operations
After a flash page write operation from an external programmer, reading (data read or code
fetch) in flash may fail. This may lead to an exception or to others errors derived from this
corrupted read access.
Fix/Workaround
Before any flash page write operation, each write in the page buffer must preceded by a
write in the page buffer with 0xFFFF_FFFF content at any address in the page.
38.5.14 I/O Pins
1. PA05 is not 3.3V tolerant.
PA05 should be grounded on the PCB and left unused if VDDIO is above 1.8V.
Fix/Workaround
None.
2. No pull-up on pins that are not bonded
PB13 to PB27 are not bonded on UC3L0256/128, but has no pull-up and can cause current
consumption on VDDIO/VDDIN if left undriven.
Fix/Workaround
Enable pull-ups on PB13 to PB27 by writing 0x0FFFE000 to the PUERS1 register in the
GPIO.
3. PA17 has low ESD tolerance
PA17 only tolerates 500V ESD pulses (Human Body Model).
Fix/Workaround
Care must be taken during manufacturing and PCB design.
f
sab
7f
aw
CV – 3 = ----------------
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39. Datasheet Revision History
Please note that the referring page numbers in this section are referred to this document. The
referring revision in this section are referring to the document revision.
39.1 Rev. D – 06/2013
39.2 Rev. C – 01/2012
39.3 Rev. B – 12/2011
39.4 Rev. A – 12/2011
1. Updated the datasheet with a new ATmel blue logo and the last page.
2. Added Flash errata.
1. Description: DFLL frequency is 20 to 150MHz, not 40 to 150MHz.
2. Block Diagram: GCLK_IN is input, not output. CAT SMP corrected from I/O to output. SPI
NPCS corrected from output to I/O.
3, Package and Pinout: EXTINT0 in Signal Descriptions table is NMI.
4, Supply and Startup Considerations: In 1.8V single supply mode figure, the input voltage is
1.62-1.98V, not 1.98-3.6V. “On system start-up, the DFLL is disabled” is replaced by “On
system start-up, all high-speed clocks are disabled”.
5, ADCIFB: PRND signal removed from block diagram.
6, Electrical Charateristics: Added 64-pin package information to I/O Pin Characteristics tables
and Digital Clock Characteristics table.
7, Mechanical Characteristics: QFN48 Package Drawing updated. Note that the package drawing
for QFN48 is correct in datasheet rev A, but wrong in rev B. Added notes to package drawings.
8. Summary: Removed Programming and Debugging chapter, added Processor and Architecture
chapter.
1. JTAG Data Registers subchapter added in the Programming and Debugging chapter,
containing JTAG IDs.
1. Initial revision.
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Table of Contents
Features ..................................................................................................... 1
1 Description ............................................................................................... 3
2 Overview ................................................................................................... 5
2.1 Block Diagram ...................................................................................................5
2.2 Configuration Summary .....................................................................................6
3 Package and Pinout ................................................................................. 7
3.1 Package .............................................................................................................7
3.2 See Section 3.3 for a description of the various peripheral signals. ................12
3.3 Signal Descriptions ..........................................................................................15
3.4 I/O Line Considerations ...................................................................................18
4 Processor and Architecture .................................................................. 21
4.1 Features ..........................................................................................................21
4.2 AVR32 Architecture .........................................................................................21
4.3 The AVR32UC CPU ........................................................................................22
4.4 Programming Model ........................................................................................26
4.5 Exceptions and Interrupts ................................................................................30
5 Memories ................................................................................................ 35
5.1 Embedded Memories ......................................................................................35
5.2 Physical Memory Map .....................................................................................35
5.3 Peripheral Address Map ..................................................................................36
5.4 CPU Local Bus Mapping .................................................................................37
6 Supply and Startup Considerations ..................................................... 39
6.1 Supply Considerations .....................................................................................39
6.2 Startup Considerations ....................................................................................44
7 Peripheral DMA Controller (PDCA) ...................................................... 45
7.1 Features ..........................................................................................................45
7.2 Overview ..........................................................................................................45
7.3 Block Diagram .................................................................................................46
7.4 Product Dependencies ....................................................................................46
7.5 Functional Description .....................................................................................47
7.6 Performance Monitors .....................................................................................49
7.7 User Interface ..................................................................................................51
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7.8 Module Configuration ......................................................................................79
8 USB Interface (USBC) ............................................................................ 81
8.1 Features ..........................................................................................................81
8.2 Overview ..........................................................................................................81
8.3 Block Diagram .................................................................................................81
8.4 I/O Lines Description .......................................................................................83
8.5 Product Dependencies ....................................................................................84
8.6 Functional Description .....................................................................................85
8.7 User Interface ...............................................................................................101
8.8 Module Configuration ....................................................................................134
9 Flash Controller (FLASHCDW) ........................................................... 135
9.1 Features ........................................................................................................135
9.2 Overview ........................................................................................................135
9.3 Product Dependencies ..................................................................................135
9.4 Functional Description ...................................................................................136
9.5 Flash Commands ..........................................................................................141
9.6 General-purpose Fuse Bits ............................................................................143
9.7 Security Bit ....................................................................................................146
9.8 User Interface ................................................................................................147
9.9 Fuse Settings .................................................................................................157
9.10 Serial Number ................................................................................................160
9.11 Module Configuration ....................................................................................160
10 Secure Access Unit (SAU) .................................................................. 162
10.1 Features ........................................................................................................162
10.2 Overview ........................................................................................................162
10.3 Block Diagram ...............................................................................................163
10.4 Product Dependencies ..................................................................................164
10.5 Functional Description ...................................................................................164
10.6 User Interface ................................................................................................168
10.7 Module Configuration ....................................................................................183
11 HSB Bus Matrix (HMATRIXB) .............................................................. 184
11.1 Features ........................................................................................................184
11.2 Overview ........................................................................................................184
11.3 Product Dependencies ..................................................................................184
11.4 Functional Description ...................................................................................184
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11.5 User Interface ................................................................................................188
11.6 Module Configuration ....................................................................................196
12 Interrupt Controller (INTC) .................................................................. 198
12.1 Features ........................................................................................................198
12.2 Overview ........................................................................................................198
12.3 Block Diagram ...............................................................................................198
12.4 Product Dependencies ..................................................................................199
12.5 Functional Description ...................................................................................199
12.6 User Interface ................................................................................................202
12.7 Module Configuration ....................................................................................206
12.8 Interrupt Request Signal Map ........................................................................206
13 Power Manager (PM) ............................................................................ 209
13.1 Features ........................................................................................................209
13.2 Overview ........................................................................................................209
13.3 Block Diagram ...............................................................................................210
13.4 I/O Lines Description .....................................................................................210
13.5 Product Dependencies ..................................................................................210
13.6 Functional Description ...................................................................................211
13.7 User Interface ................................................................................................220
13.8 Module Configuration ....................................................................................243
14 System Control Interface (SCIF) ......................................................... 244
14.1 Features ........................................................................................................244
14.2 Overview ........................................................................................................244
14.3 I/O Lines Description .....................................................................................244
14.4 Product Dependencies ..................................................................................244
14.5 Functional Description ...................................................................................245
14.6 User Interface ................................................................................................265
14.7 Module Configuration ....................................................................................318
15 Asynchronous Timer (AST) ................................................................ 322
15.1 Features ........................................................................................................322
15.2 Overview ........................................................................................................322
15.3 Block Diagram ...............................................................................................323
15.4 Product Dependencies ..................................................................................323
15.5 Functional Description ...................................................................................324
15.6 User Interface ................................................................................................330
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15.7 Module Configuration ....................................................................................351
16 Watchdog Timer (WDT) ....................................................................... 352
16.1 Features ........................................................................................................352
16.2 Overview ........................................................................................................352
16.3 Block Diagram ...............................................................................................352
16.4 Product Dependencies ..................................................................................352
16.5 Functional Description ...................................................................................353
16.6 User Interface ................................................................................................358
16.7 Module Configuration ....................................................................................364
17 External Interrupt Controller (EIC) ..................................................... 365
17.1 Features ........................................................................................................365
17.2 Overview ........................................................................................................365
17.3 Block Diagram ...............................................................................................365
17.4 I/O Lines Description .....................................................................................366
17.5 Product Dependencies ..................................................................................366
17.6 Functional Description ...................................................................................366
17.7 User Interface ................................................................................................370
17.8 Module Configuration ....................................................................................386
18 Frequency Meter (FREQM) .................................................................. 387
18.1 Features ........................................................................................................387
18.2 Overview ........................................................................................................387
18.3 Block Diagram ...............................................................................................387
18.4 Product Dependencies ..................................................................................387
18.5 Functional Description ...................................................................................388
18.6 User Interface ................................................................................................390
18.7 Module Configuration ....................................................................................401
19 General-Purpose Input/Output Controller (GPIO) ............................. 403
19.1 Features ........................................................................................................403
19.2 Overview ........................................................................................................403
19.3 Block Diagram ...............................................................................................403
19.4 I/O Lines Description .....................................................................................404
19.5 Product Dependencies ..................................................................................404
19.6 Functional Description ...................................................................................405
19.7 User Interface ................................................................................................410
19.8 Module Configuration ....................................................................................433
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20 Universal Synchronous Asynchronous Receiver Transmitter (USART)
434
20.1 Features ........................................................................................................434
20.2 Overview ........................................................................................................434
20.3 Block Diagram ...............................................................................................435
20.4 I/O Lines Description ....................................................................................436
20.5 Product Dependencies ..................................................................................436
20.6 Functional Description ...................................................................................437
20.7 User Interface ................................................................................................463
20.8 Module Configuration ....................................................................................485
21 Serial Peripheral Interface (SPI) ......................................................... 486
21.1 Features ........................................................................................................486
21.2 Overview ........................................................................................................486
21.3 Block Diagram ...............................................................................................487
21.4 Application Block Diagram .............................................................................487
21.5 I/O Lines Description .....................................................................................488
21.6 Product Dependencies ..................................................................................488
21.7 Functional Description ...................................................................................488
21.8 User Interface ................................................................................................499
21.9 Module Configuration ....................................................................................526
22 Two-wire Master Interface (TWIM) ...................................................... 527
22.1 Features ........................................................................................................527
22.2 Overview ........................................................................................................527
22.3 List of Abbreviations ......................................................................................528
22.4 Block Diagram ...............................................................................................528
22.5 Application Block Diagram .............................................................................529
22.6 I/O Lines Description .....................................................................................529
22.7 Product Dependencies ..................................................................................529
22.8 Functional Description ...................................................................................531
22.9 User Interface ................................................................................................543
22.10 Module Configuration ....................................................................................560
23 Two-wire Slave Interface (TWIS) ......................................................... 561
23.1 Features ........................................................................................................561
23.2 Overview ........................................................................................................561
23.3 List of Abbreviations ......................................................................................562
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23.4 Block Diagram ...............................................................................................562
23.5 Application Block Diagram .............................................................................563
23.6 I/O Lines Description .....................................................................................563
23.7 Product Dependencies ..................................................................................563
23.8 Functional Description ...................................................................................564
23.9 User Interface ................................................................................................574
23.10 Module Configuration ....................................................................................590
24 Inter-IC Sound Controller (IISC) .......................................................... 591
24.1 Features ........................................................................................................591
24.2 Overview ........................................................................................................591
24.3 Block Diagram ...............................................................................................592
24.4 I/O Lines Description .....................................................................................592
24.5 Product Dependencies ..................................................................................592
24.6 Functional Description ...................................................................................593
24.7 IISC Application Examples ............................................................................598
24.8 User Interface ................................................................................................600
24.9 Module configuration .....................................................................................614
25 Pulse Width Modulation Controller (PWMA) ..................................... 615
25.1 Features ........................................................................................................615
25.2 Overview ........................................................................................................615
25.3 Block Diagram ...............................................................................................616
25.4 I/O Lines Description .....................................................................................616
25.5 Product Dependencies ..................................................................................616
25.6 Functional Description ...................................................................................617
25.7 User Interface ................................................................................................623
25.8 Module Configuration ....................................................................................641
26 Timer/Counter (TC) .............................................................................. 642
26.1 Features ........................................................................................................642
26.2 Overview ........................................................................................................642
26.3 Block Diagram ...............................................................................................643
26.4 I/O Lines Description .....................................................................................643
26.5 Product Dependencies ..................................................................................643
26.6 Functional Description ...................................................................................644
26.7 User Interface ................................................................................................659
26.8 Module Configuration ....................................................................................682
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27 Peripheral Event System ..................................................................... 683
27.1 Features ........................................................................................................683
27.2 Overview ........................................................................................................683
27.3 Peripheral Event System Block Diagram .......................................................683
27.4 Functional Description ...................................................................................683
27.5 Application Example ......................................................................................686
28 Audio Bit Stream DAC (ABDACB) ...................................................... 687
28.1 Features ........................................................................................................687
28.2 Overview ........................................................................................................687
28.3 Block Diagram ...............................................................................................687
28.4 I/O Lines Description .....................................................................................688
28.5 Product Dependencies ..................................................................................688
28.6 Functional Description ...................................................................................689
28.7 User Interface ................................................................................................696
28.8 Module Configuration ....................................................................................710
29 ADC Interface (ADCIFB) ...................................................................... 711
29.1 Features ........................................................................................................711
29.2 Overview ........................................................................................................711
29.3 Block Diagram ...............................................................................................712
29.4 I/O Lines Description .....................................................................................713
29.5 Product Dependencies ..................................................................................713
29.6 Functional Description ...................................................................................714
29.7 Resistive Touch Screen .................................................................................718
29.8 Operating Modes ...........................................................................................724
29.9 User Interface ................................................................................................726
29.10 Module Configuration ....................................................................................745
30 Analog Comparator Interface (ACIFB) ............................................... 746
30.1 Features ........................................................................................................746
30.2 Overview ........................................................................................................746
30.3 Block Diagram ...............................................................................................747
30.4 I/O Lines Description .....................................................................................747
30.5 Product Dependencies ..................................................................................748
30.6 Functional Description ...................................................................................749
30.7 Peripheral Event Triggers ..............................................................................754
30.8 AC Test mode ................................................................................................754
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30.9 User Interface ................................................................................................755
30.10 Module Configuration ....................................................................................769
31 Capacitive Touch Module (CAT) ......................................................... 770
31.1 Features ........................................................................................................770
31.2 Overview ........................................................................................................770
31.3 Block Diagram ...............................................................................................771
31.4 I/O Lines Description .....................................................................................771
31.5 Product Dependencies ..................................................................................772
31.6 Functional Description ...................................................................................774
31.7 User Interface ................................................................................................781
31.8 Module Configuration ....................................................................................816
32 Glue Logic Controller (GLOC) ............................................................ 817
32.1 Features ........................................................................................................817
32.2 Overview ........................................................................................................817
32.3 Block Diagram ...............................................................................................817
32.4 I/O Lines Description .....................................................................................818
32.5 Product Dependencies ..................................................................................818
32.6 Functional Description ...................................................................................818
32.7 User Interface ................................................................................................820
32.8 Module Configuration ....................................................................................825
33 aWire UART (AW) ................................................................................. 826
33.1 Features ........................................................................................................826
33.2 Overview ........................................................................................................826
33.3 Block Diagram ...............................................................................................826
33.4 I/O Lines Description .....................................................................................827
33.5 Product Dependencies ..................................................................................827
33.6 Functional Description ...................................................................................827
33.7 User Interface ................................................................................................830
33.8 Module Configuration ....................................................................................843
34 Programming and Debugging ............................................................ 844
34.1 Overview ........................................................................................................844
34.2 Service Access Bus .......................................................................................844
34.3 On-Chip Debug ..............................................................................................847
34.4 JTAG and Boundary-scan (JTAG) .................................................................855
34.5 JTAG Instruction Summary ...........................................................................863
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34.6 aWire Debug Interface (AW) .........................................................................880
35 Electrical Characteristics .................................................................... 897
35.1 Absolute Maximum Ratings* .........................................................................897
35.2 Supply Characteristics ...................................................................................897
35.3 Maximum Clock Frequencies ........................................................................898
35.4 Power Consumption ......................................................................................898
35.5 I/O Pin Characteristics ...................................................................................902
35.6 Oscillator Characteristics ...............................................................................905
35.7 Flash Characteristics .....................................................................................910
35.8 ABDACB Electrical Characteristics. .............................................................911
35.9 Analog Characteristics ...................................................................................912
35.10 Timing Characteristics ...................................................................................921
36 Mechanical Characteristics ................................................................. 931
36.1 Thermal Considerations ................................................................................931
36.2 Package Drawings .........................................................................................932
36.3 Soldering Profile ............................................................................................937
37 Ordering Information ........................................................................... 938
38 Errata ..................................................................................................... 940
38.1 Rev. C ............................................................................................................940
38.2 Flash ..............................................................................................................942
38.3 Rev. B ............................................................................................................942
38.4 Flash .............................................................................................................946
38.5 Rev. A ............................................................................................................946
39 Datasheet Revision History ................................................................ 953
39.1 Rev. D – 06/2013 ...........................................................................................953
39.2 Rev. C – 01/2012 ...........................................................................................953
39.3 Rev. B – 12/2011 ...........................................................................................953
39.4 Rev. A – 12/2011 ...........................................................................................953
Table of Contents....................................................................................... i
Atmel Corporation
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© 2013 Atmel Corporation. All rights reserved. / Rev.: 32142D–AVR32–06/2013
Atmel®, logo and combinations thereof, AVR®, picoPower®, QTouch®, AKS® and others are registered trademarks or trademarks of Atmel Corporation
or its subsidiaries. Other terms and product names may be trademarks of others.
Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this
document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN THE ATMEL TERMS AND CONDITIONS OF SALES LOCATED ON THE ATMEL WEBSITE, ATMEL ASSUMES
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INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Atmel makes no
representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to specifications and products descriptions at any time
without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided otherwise, Atmel products are not suitable for, and shall not be used in,
automotive applications. Atmel products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life.
2015 Microchip Technology Inc. DS00001625B-page 1
General Description
The CAP1133, which incorporates RightTouch® technology,
is a multiple channel Capacitive Touch sensor
with multiple power LED drivers. It contains three (3)
individual capacitive touch sensor inputs with programmable
sensitivity for use in touch sensor applications.
Each sensor input automatically recalibrates to compensate
for gradual environmental changes.
The CAP1133 also contains three (3) LED drivers that
offer full-on / off, variable rate blinking, dimness controls,
and breathing. Each of the LED drivers may be
linked to one of the sensor inputs to be actuated when
a touch is detected. As well, each LED driver may be
individually controlled via a host controller.
The CAP1133 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons
to be touched simultaneously. If this pattern is
detected, then a status bit is set and an interrupt generated.
Additionally, the CAP1133 includes circuitry and support
for enhanced sensor proximity detection.
The CAP1133 offers multiple power states operating at
low quiescent currents. In the Standby state of operation,
one or more capacitive touch sensor inputs are
active and all LEDs may be used.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor
inputs are active. Communications will wake the
device.
Applications
• Desktop and Notebook PCs
• LCD Monitors
• Consumer Electronics
• Appliances
Features
• Three (3) Capacitive Touch Sensor Inputs
- Programmable sensitivity
- Automatic recalibration
- Individual thresholds for each button
• Proximity Detection
• Multiple Button Pattern Detection
• Calibrates for Parasitic Capacitance
• Analog Filtering for System Noise Sources
• Press and Hold feature for Volume-like Applications
• SMBus / I2C Compliant Communication Interface
• Low Power Operation
- 5uA quiescent current in Deep Sleep
- 50uA quiescent current in Standby (1 sensor
input monitored)
- Samples one or more channels in Standby
• Three (3) LED Driver Outputs
- Open Drain or Push-Pull
- Programmable blink, breathe, and dimness
controls
- Can be linked to Capacitive Touch Sensor
inputs
• Available in 10-pin 3mm x 3mm RoHS compliant
DFN package
CAP1133
3 Channel Capacitive Touch Sensor with 3 LED Drivers
CAP1133
DS00001625B-page 2 2015 Microchip Technology Inc.
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The last character of the literature number is the version number, (e.g., DS30000000A is version A of document DS30000000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the
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To determine if an errata sheet exists for a particular device, please check with one of the following:
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When contacting a sales office, please specify which device, revision of silicon and data sheet (include -literature number) you are
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2015 Microchip Technology Inc. DS00001625B-page 3
CAP1133
Table of Contents
1.0 Block Diagram ................................................................................................................................................................................. 4
2.0 Pin Description ................................................................................................................................................................................ 5
3.0 Electrical Specifications .................................................................................................................................................................. 9
4.0 Communications ........................................................................................................................................................................... 12
5.0 General Description ...................................................................................................................................................................... 23
6.0 Register Description ...................................................................................................................................................................... 29
7.0 Package Information ..................................................................................................................................................................... 67
Appendix A: Device Delta ................................................................................................................................................................... 72
Appendix B: Data Sheet Revision History ........................................................................................................................................... 74
The Microchip Web Site ...................................................................................................................................................................... 76
Customer Change Notification Service ............................................................................................................................................... 76
Customer Support ............................................................................................................................................................................... 76
Product Identification System ............................................................................................................................................................. 77
CAP1133
DS00001625B-page 4 2015 Microchip Technology Inc.
1.0 BLOCK DIAGRAM
SMBus
Slave
Protocol
SMCLK
SMDATA
VDD GND
ALERT#
Capacitive Touch Sensing
Algorithm
CS1 CS2 CS3
LED1
LED Driver, Breathe, and
Dimness control
LED2 LED3
2015 Microchip Technology Inc. DS00001625B-page 5
CAP1133
2.0 PIN DESCRIPTION
FIGURE 2-1: CAP1133 Pin Diagram (10-Pin DFN)
TABLE 2-1: PIN DESCRIPTION FOR CAP1133
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
1 ALERT#
Active low alert / interrupt output usable for SMBus alert OD (5V) Connect to
Ground
Active high alert / interrupt output usable for SMBus alert DO leave open
2 SMDATA Bi-directional, open-drain SMBus data - requires pull-up DIOD (5V)
n/a
3 SMCLK SMBus clock input - requires pull-up resistor DI (5V)
4 VDD Positive Power supply Power n/a
5 LED1
Open drain LED 1 driver (default) OD (5V) Connect to
Ground
Push-pull LED 1 driver DO leave open or
connect to Ground
6 LED2
Open drain LED 2 driver (default) OD (5V) Connect to
Ground
Push-pull LED 2 driver DO leave open or
connect to Ground
7 LED3
Open drain LED 3 driver (default) OD (5V) Connect to
Ground
Push-pull LED 3 driver DO leave open or
connect to Ground
GND
CS2
1 CS1
2
3
4
5
CS3
LED1
ALERT#
SMDATA
VDD
SMCLK
LED3
LED2
CAP1133
3mm x 3mm DFN
10
9
8
7
6
CAP1133
DS00001625B-page 6 2015 Microchip Technology Inc.
APPLICATION NOTE: When the ALERT# pinis configured as an active low output, it will be open drain. When it is
configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1133 is unpowered.
The pin types are described in Table 2-2. All pins labeled with (5V) are 5V tolerant.
8 CS3 Capacitive Touch Sensor Input 3 AIO Connect to
Ground
9 CS2 Capacitive Touch Sensor Input 2 AIO Connect to
Ground
10 CS1 Capacitive Touch Sensor Input 1 AIO Connect to
Ground
Bottom
Pad GND Ground Power n/a
TABLE 2-2: PIN TYPES
Pin Type Description
Power This pin is used to supply power or ground to the device.
DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
AIO Analog Input / Output -This pin is used as an I/O for analog signals.
DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output,
it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a
pull-up resistor. This pin is 5V tolerant.
DO Push-pull Digital Output - This pin is used as a digital output and can sink and source current.
DIO Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
TABLE 2-1: PIN DESCRIPTION FOR CAP1133 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
2015 Microchip Technology Inc. DS00001625B-page 7
CAP1133
3.0 ELECTRICAL SPECIFICATIONS
Note 3-1 Stresses above those listed could cause permanent damage to the device. This is a stress rating
only and functional operation of the device at any other condition above those indicated in the
operation sections of this specification is not implied.
Note 3-2 For the 5V tolerant pins that have a pull-up resistor, the voltage difference between V5VT_PIN and VDD
must never exceed 3.6V.
Note 3-3 The Package Power Dissipation specification assumes a recommended thermal via design consisting
of a 2x2 matrix of 0.3mm (12mil) vias at 1.0mm pitch connected to the ground plane with a 1.6 x
2.3mm thermal landing.
TABLE 3-1: ABSOLUTE MAXIMUM RATINGS
Voltage on 5V tolerant pins (V5VT_PIN) -0.3 to 5.5 V
Voltage on 5V tolerant pins (|V5VT_PIN - VDD|) Note 3-2 0 to 3.6 V
Voltage on VDD pin -0.3 to 4 V
Voltage on any other pin to GND -0.3 to VDD + 0.3 V
Package Power Dissipation up to TA = 85°C for 10 pin DFN
(see Note 3-3)
0.7 W
Junction to Ambient (θJA) 77.7 °C/W
Operating Ambient Temperature Range -40 to 125 °C
Storage Temperature Range -55 to 150 °C
ESD Rating, All Pins, HBM 8000 V
CAP1133
DS00001625B-page 8 2015 Microchip Technology Inc.
TABLE 3-2: ELECTRICAL SPECIFICATIONS
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
DC Power
Supply Voltage VDD 3.0 3.3 3.6 V
Supply Current
ISTBY 120 170 uA
Standby state active
1 sensor input monitored
No LEDs active
Default conditions (8 avg, 70ms
cycle time)
ISTBY 50 uA
Standby state active
1 sensor input monitored
No LEDs active
1 avg, 140ms cycle time,
IDSLEEP 5 15 uA
Deep Sleep state active
LEDs at 100% or 0% Duty Cycle
No communications
TA < 40°C
3.135 < VDD < 3.465V
IDD 500 600 uA Capacitive Sensing Active
No LEDs active
Capacitive Touch Sensor Inputs
Maximum Base
Capacitance CBASE 50 pF Pad untouched
Minimum Detectable
Capacitive Shift ΔCTOUCH 20 fF
Pad touched - default conditions (1
avg, 35ms cycle time, 1x sensitivity)
Recommended Cap
Shift ΔCTOUCH 0.1 2 pF Pad touched - Not tested
Power Supply Rejection
PSR ±3 ±10 counts /
V
Untouched Current Counts
Base Capacitance 5pF - 50pF
Maximum sensitivity
Negative Delta Counts disabled
All other parameters default
Timing
Time to communications
ready tCOMM_DLY 15 ms
Time to first conversion
ready tCONV_DLY 170 200 ms
LED Drivers
Duty Cycle DUTYLED 0 100 % Programmable
Drive Frequency fLED 2 kHz
Sinking Current ISINK 24 mA VOL = 0.4
Sourcing Current ISOURCE 24 mA VOH = VDD - 0.4
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
I/O Pins
Output Low Voltage VOL 0.4 V ISINK_IO = 8mA
Output High Voltage VOH VDD - 0.4 V ISOURCE_IO = 8mA
Input High Voltage VIH 2.0 V
2015 Microchip Technology Inc. DS00001625B-page 9
CAP1133
Note 3-4 The ALERT pin will not glitch high or low at power up if connected to VDD or another voltage.
Note 3-5 The SMCLK and SMDATA pins will not glitch low at power up if connected to VDD or another voltage.
Input Low Voltage VIL 0.8 V
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
SMBus Timing
Input Capacitance CIN 5 pF
Clock Frequency fSMB 10 400 kHz
Spike Suppression tSP 50 ns
Bus Free Time Stop to
Start tBUF 1.3 us
Start Setup Time tSU:STA 0.6 us
Start Hold Time tHD:STA 0.6 us
Stop Setup Time tSU:STO 0.6 us
Data Hold Time tHD:DAT 0 us When transmitting to the master
Data Hold Time tHD:DAT 0.3 us When receiving from the master
Data Setup Time tSU:DAT 0.6 us
Clock Low Period tLOW 1.3 us
Clock High Period tHIGH 0.6 us
Clock / Data Fall Time tFALL 300 ns Min = 20+0.1CLOAD ns
Clock / Data Rise
Time tRISE 300 ns Min = 20+0.1CLOAD ns
Capacitive Load CLOAD 400 pF per bus line
TABLE 3-2: ELECTRICAL SPECIFICATIONS (CONTINUED)
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
CAP1133
DS00001625B-page 10 2015 Microchip Technology Inc.
4.0 COMMUNICATIONS
4.1 Communications
The CAP1133 communicates using the SMBus or I2C protocol.
The supports the following protocols: Send Byte, Receive Byte, Read Byte, Write Byte, Read Block, and Write Block.
In addition, the device supports I2C formatting for block read and block write protocols.
4.2 System Management Bus
The CAP1133 communicates with a host controller, such as an SIO, through the SMBus. The SMBus is a two-wire serial
communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in
Figure 4-1. Stretching of the SMCLK signal is supported; however, the CAP1133 will not stretch the clock signal.
4.2.1 SMBUS START BIT
The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the
SMBus Clock line is in a logic ‘1’ state.
4.2.2 SMBUS ADDRESS AND RD / WR BIT
The SMBus Address Byte consists of the 7-bit slave address followed by the RD / WR indicator bit. If this RD / WR bit
is a logic ‘0’, then the SMBus Host is writing data to the slave device. If this RD / WR bit is a logic ‘1’, then the SMBus
Host is reading data from the slave device.
The CAP1133 responds to SMBus address 0101_000(r/w).
4.2.3 SMBUS DATA BYTES
All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.
4.2.4 SMBUS ACK AND NACK BITS
The SMBus slave will acknowledge all data bytes that it receives. This is done by the slave device pulling the SMBus
Data line low after the 8th bit of each byte that is transmitted. This applies to both the Write Byte and Block Write protocols.
The Host will NACK (not acknowledge) the last data byte to be received from the slave by holding the SMBus data line
high after the 8th data bit has been sent. For the Block Read protocol, the Host will ACK each data byte that it receives
except the last data byte.
FIGURE 4-1: SMBus Timing Diagram
SMDATA
SMCLK
TLOW
TRISE
THIGH
TFALL
TBUF
THD:STA
P S S - Start Condition P - Stop Condition
THD:DAT TSU:DAT TSU:STA
THD:STA
P
TSU:STO
S
2015 Microchip Technology Inc. DS00001625B-page 11
CAP1133
4.2.5 SMBUS STOP BIT
The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the
SMBus clock line is in a logic ‘1’ state. When the CAP1133 detects an SMBus Stop bit and it has been communicating
with the SMBus protocol, it will reset its slave interface and prepare to receive further communications.
4.2.6 SMBUS TIMEOUT
The CAP1133 includes an SMBus timeout feature. Following a 30ms period of inactivity on the SMBus where the
SMCLK pin is held low, the device will timeout and reset the SMBus interface.
The timeout function defaults to disabled. It can be enabled by setting the TIMEOUT bit in the Configuration register
(see Section 6.6, "Configuration Registers").
4.2.7 SMBUS AND I2C COMPATIBILITY
The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus
2.0 and I2C specifications. For information on using the CAP1133 in an I2C system, refer to AN 14.0 Dedicated Slave
Devices in I2C Systems.
1. CAP1133 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz.
2. Minimum frequency for SMBus communications is 10kHz.
3. The SMBus slave protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality
is disabled by default in the CAP1133 and can be enabled by writing to the TIMEOUT bit. I2C does not have
a timeout.
4. The SMBus slave protocol will reset if both the clock and data lines are held at a logic ‘1’ for longer than 200µs
(idle condition). This function is disabled by default in the CAP1133 and can be enabled by writing to the TIMEOUT
bit. I2C does not have an idle condition.
5. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus).
6. I2C devices support block read and write differently. I2C protocol allows for unlimited number of bytes to be sent
in either direction. The SMBus protocol requires that an additional data byte indicating number of bytes to read /
write is transmitted. The CAP1133 supports I2C formatting only.
4.3 SMBus Protocols
The CAP1133 is SMBus 2.0 compatible and supports Write Byte, Read Byte, Send Byte, and Receive Byte as valid
protocols as shown below.
All of the below protocols use the convention in Table 4-1.
4.3.1 SMBUS WRITE BYTE
The Write Byte is used to write one byte of data to a specific register as shown in Table 4-2.
4.3.2 SMBUS READ BYTE
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4-3.
TABLE 4-1: PROTOCOL FORMAT
Data Sent to
Device
Data Sent to the
HOst
Data sent Data sent
TABLE 4-2: WRITE BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK Stop
1 ->0 0101_000 0 0 XXh 0 XXh 0 0 -> 1
CAP1133
DS00001625B-page 12 2015 Microchip Technology Inc.
4.3.3 SMBUS SEND BYTE
The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is
transferred during the Send Byte protocol as shown in Table 4-4.
APPLICATION NOTE: The Send Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.3.4 SMBUS RECEIVE BYTE
The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to
be at the right location (e.g., set via Send Byte). This is used for consecutive reads of the same register as shown in
Table 4-5.
APPLICATION NOTE: The Receive Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.4 I2C Protocols
The CAP1133 supports I2C Block Write and Block Read.
The protocols listed below use the convention in Table 4-1.
4.4.1 BLOCK WRITE
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in Table 4-6.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.4.2 BLOCK READ
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in Table 4-7.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
TABLE 4-3: READ BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data NACK Stop
1->0 0101_000 0 0 XXh 0 1 ->0 0101_000 1 0 XXh 1 0 -> 1
TABLE 4-4: SEND BYTE PROTOCOL
Start Slave Address WR ACK Register Address ACK Stop
1 -> 0 0101_000 0 0 XXh 0 0 -> 1
TABLE 4-5: RECEIVE BYTE PROTOCOL
Start Slave Address RD ACK Register Data NACK Stop
1 -> 0 0101_000 1 0 XXh 1 0 -> 1
TABLE 4-6: BLOCK WRITE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK
1 ->0 0101_000 0 0 XXh 0 XXh 0
Register Data ACK Register
Data
ACK . . . Register
Data
ACK Stop
XXh 0 XXh 0 . . . XXh 0 0 -> 1
2015 Microchip Technology Inc. DS00001625B-page 13
CAP1133
TABLE 4-7: BLOCK READ PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data
1->0 0101_000 0 0 XXh 0 1 ->0 0101_000 1 0 XXh
ACK Register
Data
ACK Register
Data
ACK Register
Data
ACK . . . Register
Data
NACK Stop
0 XXh 0 XXh 0 XXh 0 . . . XXh 1 0 -> 1
CAP1133
DS00001625B-page 14 2015 Microchip Technology Inc.
5.0 GENERAL DESCRIPTION
The CAP1133 is a multiple channel Capacitive Touch sensor with multiple power LED drivers. It contains three (3) individual
capacitive touch sensor inputs with programmable sensitivity for use in touch sensor applications. Each sensor
input automatically recalibrates to compensate for gradual environmental changes.
The CAP1133 also contains three (3) low side (or push-pull) LED drivers that offer full-on / off, variable rate blinking,
dimness controls, and breathing. Each of the LED drivers may be linked to one of the sensor inputs to be actuated when
a touch is detected. As well, each LED driver may be individually controlled via a host controller.
The CAP1133 offers multiple power states. It operates at the lowest quiescent current during its Deep Sleep state. In
the low power Standby state, it can monitor one or more channels and respond to communications normally.
The device communicates with a host controller using SMBus / I2C. The host controller may poll the device for updated
information at any time or it may configure the device to flag an interrupt whenever a touch is detected on any sensor
pad.
A typical system diagram is shown in Figure 5-1.
5.1 Power States
The CAP1133 has three operating states depending on the status of the STBY and DSLEEP bits. When the device transitions
between power states, previously detected touches (for inactive channels) are cleared and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active capacitive sensor inputs and driving all LED channels
as defined.
2. Standby - The device is in a lower power state. It will measure a programmable number of channels using the
Standby Configuration controls (see Section 6.20 through Section 6.22). Interrupts will still be generated based
on the active channels. The device will still respond to communications normally and can be returned to the Fully
Active state of operation by clearing the STBY bit.
FIGURE 5-1: System Diagram for CAP1133
CAP1133
LED3
SMDATA
SMCLK
Embedded Controller
VDD
ALERT#
LED2
LED1
CS3
CS2
CS1
Touch
Button
Touch
Button
Touch
Button
3.3V – 5V
2015 Microchip Technology Inc. DS00001625B-page 15
CAP1133
3. Deep Sleep - The device is in its lowest power state. It is not monitoring any capacitive sensor inputs and not
driving any LEDs. All LEDs will be driven to their programmed non-actuated state and no PWM operations will
be done. While in Deep Sleep, the device can be awakened by SMBus communications targeting the device.
This will not cause the DSLEEP to be cleared so the device will return to Deep Sleep once all communications
have stopped.
APPLICATION NOTE: In the Deep Sleep state, the LED output will be either high or low and will not be PWM’d at
the min or max duty cycle.
5.2 LED Drivers
The CAP1133 contains three (3) LED drivers. Each LED driver can be linked to its respective capacitive touch sensor
input or it can be controlled by the host. Each LED driver can be configured to operate in one of the following modes
with either push-pull or open drain drive.
1. Direct - The LED is configured to be on or off when the corresponding input stimulus is on or off (or inverted). The
brightness of the LED can be programmed from full off to full on (default). Additionally, the LED contains controls
to individually configure ramping on, off, and turn-off delay.
2. Pulse 1 - The LED is configured to “Pulse” (transition ON-OFF-ON) a programmable number of times with programmable
rate and min / max brightness. This behavior may be actuated when a press is detected or when a
release is detected.
3. Pulse 2 - The LED is configured to “Pulse” while actuated and then “Pulse” a programmable number of times with
programmable rate and min / max brightness when the sensor pad is released.
4. Breathe - The LED is configured to transition continuously ON-OFF-ON (i.e. to “Breathe”) with a programmable
rate and min / max brightness.
When an LED is not linked to a sensor and is actuated by the host, there’s an option to assert the ALERT# pin when
the initiated LED behavior has completed.
5.2.1 LINKING LEDS TO CAPACITIVE TOUCH SENSOR INPUTS
All LEDs can be linked to the corresponding capacitive touch sensor input so that when the sensor input detects a touch,
the corresponding LED will be actuated at one of the programmed responses.
5.3 Capacitive Touch Sensing
The CAP1133 contains three (3) independent capacitive touch sensor inputs. Each sensor input has dynamic range to
detect a change of capacitance due to a touch. Additionally, each sensor input can be configured to be automatically
and routinely re-calibrated.
5.3.1 SENSING CYCLE
Each capacitive touch sensor input has controls to be activated and included in the sensing cycle. When the device is
active, it automatically initiates a sensing cycle and repeats the cycle every time it finishes. The cycle polls through each
active sensor input starting with CS1 and extending through CS3. As each capacitive touch sensor input is polled, its
measurement is compared against a baseline “Not Touched” measurement. If the delta measurement is large enough,
a touch is detected and an interrupt is generated.
The sensing cycle time is programmable (see Section 6.10, "Averaging and Sampling Configuration Register").
5.3.2 RECALIBRATING SENSOR INPUTS
There are various options for recalibrating the capacitive touch sensor inputs. Recalibration re-sets the Base Count Registers
(Section 6.24, "Sensor Input Base Count Registers") which contain the “not touched” values used for touch detection
comparisons.
APPLICATION NOTE: The device will recalibrate all sensor inputs that were disabled when it transitions from
Standby. Likewise, the device will recalibrate all sensor inputs when waking out of Deep
Sleep.
CAP1133
DS00001625B-page 16 2015 Microchip Technology Inc.
5.3.2.1 Manual Recalibration
The Calibration Activate Registers (Section 6.11, "Calibration Activate Register") force recalibration of selected sensor
inputs. When a bit is set, the corresponding capacitive touch sensor input will be recalibrated (both analog and digital).
The bit is automatically cleared once the recalibration routine has finished.
5.3.2.2 Automatic Recalibration
Each sensor input is regularly recalibrated at a programmable rate (see Section 6.17, "Recalibration Configuration Register").
By default, the recalibration routine stores the average 64 previous measurements and periodically updates the
base “not touched” setting for the capacitive touch sensor input.
5.3.2.3 Negative Delta Count Recalibration
It is possible that the device loses sensitivity to a touch. This may happen as a result of a noisy environment, an accidental
recalibration during a touch, or other environmental changes. When this occurs, the base untouched sensor input
may generate negative delta count values. The NEG_DELTA_CNT bits (see Section 6.17, "Recalibration Configuration
Register") can be set to force a recalibration after a specified number of consecutive negative delta readings.
5.3.2.4 Delayed Recalibration
It is possible that a “stuck button” occurs when something is placed on a button which causes a touch to be detected
for a long period. By setting the MAX_DUR_EN bit (see Section 6.6, "Configuration Registers"), a recalibration can be
forced when a touch is held on a button for longer than the duration specified in the MAX_DUR bits (see Section 6.8,
"Sensor Input Configuration Register").
5.3.3 PROXIMITY DETECTION
Each sensor input can be configured to detect changes in capacitance due to proximity of a touch. This circuitry detects
the change of capacitance that is generated as an object approaches, but does not physically touch, the enabled sensor
pad(s). When a sensor input is selected to perform proximity detection, it will be sampled from 1x to 128x per sampling
cycle. The larger the number of samples that are taken, the greater the range of proximity detection is available at the
cost of an increased overall sampling time.
5.3.4 MULTIPLE TOUCH PATTERN DETECTION
The multiple touch pattern (MTP) detection circuitry can be used to detect lid closure or other similar events. An event
can be flagged based on either a minimum number of sensor inputs or on specific sensor inputs simultaneously exceeding
an MTP threshold or having their Noise Flag Status Register bits set. An interrupt can also be generated. During an
MTP event, all touches are blocked (see Section 6.15, "Multiple Touch Pattern Configuration Register").
5.3.5 LOW FREQUENCY NOISE DETECTION
Each sensor input has an EMI noise detector that will sense if low frequency noise is injected onto the input with sufficient
power to corrupt the readings. If this occurs, the device will reject the corrupted sample and set the corresponding
bit in the Noise Status register to a logic ‘1’.
Note: During this recalibration routine, the sensor inputs will not detect a press for up to 200ms and the Sensor
Base Count Register values will be invalid. In addition, any press on the corresponding sensor pads will
invalidate the recalibration.
Note: Automatic recalibration only works when the delta count is below the active sensor input threshold. It is disabled
when a touch is detected.
Note: During this recalibration, the device will not respond to touches.
Note: Delayed recalibration only works when the delta count is above the active sensor input threshold. If
enabled, it is invoked when a sensor pad touch is held longer than the MAX_DUR bit setting.
2015 Microchip Technology Inc. DS00001625B-page 17
CAP1133
5.3.6 RF NOISE DETECTION
Each sensor input contains an integrated RF noise detector. This block will detect injected RF noise on the CS pin. The
detector threshold is dependent upon the noise frequency. If RF noise is detected on a CS line, that sample is removed
and not compared against the threshold.
5.4 ALERT# Pin
The ALERT# pin is an active low (or active high when configured) output that is driven when an interrupt event is
detected.
Whenever an interrupt is generated, the INT bit (see Section 6.1, "Main Control Register") is set. The ALERT# pin is
cleared when the INT bit is cleared by the user. Additionally, when the INT bit is cleared by the user, status bits are only
cleared if no touch is detected.
5.4.1 SENSOR INTERRUPT BEHAVIOR
The sensor interrupts are generated in one of two ways:
1. An interrupt is generated when a touch is detected and, as a user selectable option, when a release is detected
(by default - see Section 6.6). See Figure 5-3.
2. If the repeat rate is enabled then, so long as the touch is held, another interrupt will be generated based on the
programmed repeat rate (see Figure 5-2).
When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch
is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button
is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a
touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it
is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed
repeat rate and upon release (if enabled).
APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon
sensor pad release and an active-low ALERT# pin.
APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.
FIGURE 5-2: Sensor Interrupt Behavior - Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms)
Min Press Setting
(280ms)
Interrupt on
Touch
Button Repeat Rate
(175ms)
Button Repeat Rate
(175ms)
Interrupt on
Release
(optional)
ALERT# pin
(active low)
CAP1133
DS00001625B-page 18 2015 Microchip Technology Inc.
FIGURE 5-3: Sensor Interrupt Behavior - No Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms) Interrupt on
Touch Interrupt on
Release
(optional)
ALERT# pin
(active low)
2015 Microchip Technology Inc. DS00001625B-page 19
CAP1133
6.0 REGISTER DESCRIPTION
The registers shown in Table 6-1 are accessible through the communications protocol. An entry of ‘-’ indicates that the
bit is not used and will always read ‘0’.
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER
Register
Address R/W Register Name Function Default Value Page
00h R/W Main Control Controls general power states and
power dissipation 00h Page 21
02h R General Status Stores general status bits 00h Page 22
03h R Sensor Input Status Returns the state of the sampled
capacitive touch sensor inputs 00h Page 22
04h R LED Status Stores status bits for LEDs 00h Page 22
0Ah R Noise Flag Status Stores the noise flags for sensor inputs 00h Page 23
10h R Sensor Input 1 Delta
Count Stores the delta count for CS1 00h Page 23
11h R Sensor Input 2 Delta
Count Stores the delta count for CS2 00h Page 23
12h R Sensor Input 3 Delta
Count Stores the delta count for CS3 00h Page 23
1Fh R/W Sensitivity Control
Controls the sensitivity of the threshold
and delta counts and data scaling of
the base counts
2Fh Page 24
20h R/W Configuration Controls general functionality 20h Page 25
21h R/W Sensor Input Enable Controls whether the capacitive touch
sensor inputs are sampled 07h Page 26
22h R/W Sensor Input Configuration
Controls max duration and auto-repeat
delay for sensor inputs operating in the
full power state
A4h Page 27
23h R/W Sensor Input Configuration
2
Controls the MPRESS controls for all
sensor inputs 07h Page 28
24h R/W Averaging and Sampling
Config
Controls averaging and sampling window
39h Page 28
26h R/W Calibration Activate Forces re-calibration for capacitive
touch sensor inputs 00h Page 30
27h R/W Interrupt Enable Enables Interrupts associated with
capacitive touch sensor inputs 07h Page 30
28h R/W Repeat Rate Enable Enables repeat rate for all sensor
inputs 07h Page 30
2Ah R/W Multiple Touch Configuration
Determines the number of simultaneous
touches to flag a multiple touch
condition
80h Page 31
2Bh R/W Multiple Touch Pattern
Configuration
Determines the multiple touch pattern
(MTP) configuration 00h Page 31
2Dh R/W Multiple Touch Pattern
Determines the pattern or number of
sensor inputs used by the MTP circuitry
07h Page 32
2Fh R/W Recalibration Configuration
Determines re-calibration timing and
sampling window 8Ah Page 33
30h R/W Sensor Input 1 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 1
40h Page 34
CAP1133
DS00001625B-page 20 2015 Microchip Technology Inc.
31h R/W Sensor Input 2 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 2
40h Page 34
32h R/W Sensor Input 3 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 3
40h Page 34
38h R/W Sensor Input Noise
Threshold
Stores controls for selecting the noise
threshold for all sensor inputs 01h Page 34
Standby Configuration Registers
40h R/W Standby Channel Controls which sensor inputs are
enabled while in standby 00h Page 35
41h R/W Standby Configuration Controls averaging and cycle time
while in standby 39h Page 35
42h R/W Standby Sensitivity Controls sensitivity settings used while
in standby 02h Page 36
43h R/W Standby Threshold Stores the touch detection threshold
for active sensor inputs in standby 40h Page 37
44h R/W Configuration 2 Stores additional configuration controls
for the device 40h Page 25
Base Count Registers
50h R Sensor Input 1 Base
Count
Stores the reference count value for
sensor input 1 C8h Page 37
51h R Sensor Input 2 Base
Count
Stores the reference count value for
sensor input 2 C8h Page 37
52h R Sensor Input 3 Base
Count
Stores the reference count value for
sensor input 3 C8h Page 37
LED Controls
71h R/W LED Output Type Controls the output type for the LED
outputs 00h Page 38
72h R/W Sensor Input LED Linking
Controls linking of sensor inputs to
LED channels 00h Page 38
73h R/W LED Polarity Controls the output polarity of LEDs 00h Page 38
74h R/W LED Output Control Controls the output state of the LEDs 00h Page 39
77h R/W Linked LED
Transition Control
Controls the transition when LEDs are
linked to CS channels 00h Page 40
79h R/W LED Mirror Control Controls the mirroring of duty cycles
for the LEDs 00h Page 41
81h R/W LED Behavior 1 Controls the behavior and response of
LEDs 1 - 3 00h Page 41
84h R/W LED Pulse 1 Period Controls the period of each breathe
during a pulse 20h Page 43
85h R/W LED Pulse 2 Period Controls the period of the breathing
during breathe and pulse operation 14h Page 45
86h R/W LED Breathe Period Controls the period of an LED breathe
operation 5Dh Page 46
88h R/W LED Config Controls LED configuration 04h Page 46
90h R/W LED Pulse 1 Duty Cycle Determines the min and max duty
cycle for the pulse operation F0h Page 47
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001625B-page 21
CAP1133
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first
applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics.
Any reads to undefined registers will return 00h. Writes to undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means that the user writes
a logic ‘0’ to it.
6.1 Main Control Register
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is increased, the
effective sensitivity is likewise increased as a smaller delta capacitance is required to generate the same delta count
values. The sensitivity settings may need to be adjusted along with the gain settings such that data overflow does not
occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
91h R/W LED Pulse 2 Duty Cycle Determines the min and max duty
cycle for breathe and pulse operation F0h Page 47
92h R/W LED Breathe Duty Cycle Determines the min and max duty
cycle for the breathe operation F0h Page 47
93h R/W LED Direct Duty Cycle Determines the min and max duty
cycle for Direct mode LED operation F0h Page 47
94h R/W LED Direct Ramp Rates Determines the rising and falling edge
ramp rates of the LEDs 00h Page 47
95h R/W LED Off Delay Determines the off delay for all LED
behaviors 00h Page 48
B1h R Sensor Input 1 Calibration
Stores the upper 8-bit calibration value
for sensor input 1 00h Page 51
B2h R Sensor Input 2 Calibration
Stores the upper 8-bit calibration value
for sensor input 2 00h Page 51
B3h R Sensor Input 3 Calibration
Stores the upper 8-bit calibration value
for sensor input 3 00h Page 51
B9h R Sensor Input Calibration
LSB 1
Stores the 2 LSBs of the calibration
value for sensor inputs 1 - 3 00h Page 51
FDh R Product ID Stores a fixed value that identifies
each product 54h Page 51
FEh R Manufacturer ID Stores a fixed value that identifies
Microchip 5Dh Page 52
FFh R Revision Stores a fixed value that represents
the revision number 83h Page 52
TABLE 6-2: MAIN CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
00h R/W Main Control GAIN[1:0] STBY DSLEEP - - - INT 00h
TABLE 6-3: GAIN BIT DECODE
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
0 0 1
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1133
DS00001625B-page 22 2015 Microchip Technology Inc.
Bit 5 - STBY - Enables Standby.
• ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - Capacitive touch sensor input scanning is limited to the sensor inputs set in the Standby Channel register (see
Section 6.20). The status registers will not be cleared until read. LEDs that are linked to capacitive touch sensor
inputs will remain linked and active. Sensor inputs that are no longer sampled will flag a release and then remain
in a non-touched state. LEDs that are manually controlled will be unaffected.
• Bit 4 - DSLEEP - Enables Deep Sleep by deactivating all functions. ‘0’ (default) - Sensor input scanning is active
and LEDs are functional.
• ‘1’ - All sensor input scanning is disabled. All LEDs are driven to their programmed non-actuated state and no
PWM operations will be done. The status registers are automatically cleared and the INT bit is cleared.
Bit 0 - INT - Indicates that there is an interrupt. When this bit is set, it asserts the ALERT# pin. If a channel detects a
touch and its associated interrupt enable bit is not set to a logic ‘1’, no action is taken.
This bit is cleared by writing a logic ‘0’ to it. When this bit is cleared, the ALERT# pin will be deasserted and all status
registers will be cleared if the condition has been removed.
• ‘0’ - No interrupt pending.
• ‘1’ - A touch has been detected on one or more channels and the interrupt has been asserted.
6.2 Status Registers
All status bits are cleared when the device enters the Deep Sleep (DSLEEP = ‘1’ - see Section 6.1).
6.2.1 GENERAL STATUS - 02H
Bit 4 - LED - Indicates that one or more LEDs have finished their programmed activity. This bit is set if any bit in the LED
Status register is set.
Bit 2 - MULT - Indicates that the device is blocking detected touches due to the Multiple Touch detection circuitry (see
Section 6.14). This bit will not cause the INT bit to be set and hence will not cause an interrupt.
Bit 1 - MTP - Indicates that the device has detected a number of sensor inputs that exceed the MTP threshold either via
the pattern recognition or via the number of sensor inputs (see Section 6.15). This bit will cause the INT bit to be set if
the MTP_ALERT bit is also set. This bit will not be cleared until the condition that caused it to be set has been removed.
Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status register is set.
6.2.2 SENSOR INPUT STATUS - 03H
The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value of ‘0’ in any bit
indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a touch has been detected.
01 2
10 4
11 8
TABLE 6-4: STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
02h R General Status - - - LED - MULT MTP TOUCH 00h
03h R Sensor Input Status
- - - - - CS3 CS2 CS1 00h
04h R LED Status - - - - - LED3_
DN
LED2_
DN
LED1_
DN 00h
TABLE 6-3: GAIN BIT DECODE (CONTINUED)
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
2015 Microchip Technology Inc. DS00001625B-page 23
CAP1133
All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor input is no longer
present. If a touch is still detected, the bits will not be cleared (but this will not cause the interrupt to be asserted - see
Section 6.6).
Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3. This sensor input can be linked to LED3.
Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2. This sensor input can be linked to LED2.
Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1. This sensor input can be linked to LED1.
6.2.3 LED STATUS - 04H
The LED Status Registers indicate when an LED has completed its configured behavior (see Section 6.31, "LED Behavior
Register") after being actuated by the host (see Section 6.28, "LED Output Control Register"). These bits are ignored
when the LED is linked to a capacitive sensor input. All LED Status bits are cleared when the INT bit is cleared.
Bit 2 - LED3_DN - Indicates that LED3 has finished its behavior after being actuated by the host.
Bit 1 - LED2_DN - Indicates that LED2 has finished its behavior after being actuated by the host.
Bit 0 - LED1_DN - Indicates that LED1 has finished its behavior after being actuated by the host.
6.3 Noise Flag Status Registers
The Noise Flag Status registers store status bits that are generated from the analog block if the detected noise is above
the operating region of the analog detector or the RF noise detector. These bits indicate that the most recently received
data from the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a particular
channel, the delta count value is reset to 00h and thus no touch is detected.
These bits are not sticky and will be cleared automatically if the analog block does not report a noise error.
APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP
threshold (see Section 5.3.4, "Multiple Touch Pattern Detection") even if the corresponding
delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not
counted twice.
APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a
sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,
if RF noise is detected on a sensor input, that sample will be discarded unless the
DIS_RF_NOISE bit is set.
6.4 Sensor Input Delta Count Registers
The Sensor Input Delta Count registers store the delta count that is compared against the threshold used to determine
if a touch has been detected. The count value represents a change in input due to the capacitance associated with a
touch on one of the sensor inputs and is referenced to a calibrated base “Not Touched” count value. The delta is an
instantaneous change and is updated once per sensor input per sensing cycle (see Section 5.3.1, "Sensing Cycle").
TABLE 6-5: NOISE FLAG STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
0Ah R Noise Flag Status - - - CS3_
NOISE
CS2_
NOISE
CS1_
NOISE 00h
TABLE 6-6: SENSOR INPUT DELTA COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
10h R Sensor Input 1
Delta Count Sign 64 32 16 8 4 2 1 00h
11h R Sensor Input 2
Delta Count Sign 64 32 16 8 4 2 1 00h
12h R Sensor Input 3
Delta Count Sign 64 32 16 8 4 2 1 00h
CAP1133
DS00001625B-page 24 2015 Microchip Technology Inc.
The value presented is a standard 2’s complement number. In addition, the value is capped at a value of 7Fh. A reading
of 7Fh indicates that the sensitivity settings are too high and should be adjusted accordingly (see Section 6.5).
The value is also capped at a negative value of 80h for negative delta counts which may result upon a release.
6.5 Sensitivity Control Register
The Sensitivity Control register controls the sensitivity of a touch detection.
Bits 6-4 DELTA_SENSE[2:0] - Controls the sensitivity of a touch detection. The sensitivity settings act to scale the relative
delta count value higher or lower based on the system parameters. A setting of 000b is the most sensitive while a
setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a smaller delta capacitance
corresponding to a “lighter” touch. These settings are more sensitive to noise, however, and a noisy environment may
flag more false touches with higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely, a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
Bits 3 - 0 - BASE_SHIFT[3:0] - Controls the scaling and data presentation of the Base Count registers. The higher the
value of these bits, the larger the range and the lower the resolution of the data presented. The scale factor represents
the multiplier to the bit-weighting presented in these register descriptions.
APPLICATION NOTE: The BASE_SHIFT[3:0] bits normally do not need to be updated. These settings will not affect
touch detection or sensitivity. These bits are sometimes helpful in analyzing the Cap Sensing
board performance and stability.
TABLE 6-7: SENSITIVITY CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
1Fh R/W Sensitivity Control - DELTA_SENSE[2:0] BASE_SHIFT[3:0] 2Fh
TABLE 6-8: DELTA_SENSE BIT DECODE
DELTA_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-9: BASE_SHIFT BIT DECODE
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
0 0 0 0 1x
0 0 0 1 2x
0 0 1 0 4x
0 0 1 1 8x
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CAP1133
6.6 Configuration Registers
The Configuration registers control general global functionality that affects the entire device.
6.6.1 CONFIGURATION - 20H
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
• ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The SMBus interface
will not time out if the clock line is held low. Likewise, it will not reset if both the data and clock lines are held
high for longer than 200us. This is used for I2C compliance.
• ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The SMBus interface
will time out if the clock line is held low for longer than 30ms. Likewise, it will reset if both the data and clock
lines are held high for longer than 200us.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 6.19, "Sensor Input Noise Threshold
Register") is used by the device. Setting this bit disables the feature.
• ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does not exceed the
touch threshold, the sample is discarded and not used for the automatic re-calibration routine.
• ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold is used for the
automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the corresponding channel
is set to 0. Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
• ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held indefinitely and no
re-calibration will be performed on any sensor input.
• ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than the MAX_DUR
bit settings, then the re-calibration routine will be restarted (see Section 6.8).
0 1 0 0 16x
0 1 0 1 32x
0 1 1 0 64x
0 1 1 1 128x
1 0 0 0 256x
All others 256x
(default = 1111b)
TABLE 6-10: CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
20h R/W Configuration TIMEOUT - DIS_ DIG_
NOISE
DIS_ ANA_
NOISE
MAX_
DUR_EN - --
A0h
(Rev B)
20h
(rev C)
44h R/W Configuration 2 INV_LINK_
TRAN
ALT_
POL
BLK_PWR_
CTRL
BLK_POL_
MIR
SHOW_
RF_
NOISE
DIS_
RF_
NOISE
- INT_
REL_n 40h
TABLE 6-9: BASE_SHIFT BIT DECODE (CONTINUED)
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
CAP1133
DS00001625B-page 26 2015 Microchip Technology Inc.
6.6.2 CONFIGURATION 2 - 44H
Bit 7 - INV_LINK_TRAN - Determines the behavior of the Linked LED Transition controls (see Section 6.29).
• ‘0’ (default) - The Linked LED Transition controls set the min duty cycle equal to the max duty cycle.
• ‘1’ - The Linked LED Transition controls will invert the touch signal. For example, a touch signal will be inverted to
a non-touched signal.
Bit 6 - ALT_POL - Determines the ALERT# pin polarity and behavior.
• ‘0’ - The ALERT# pin is active high and push-pull.
• ‘1’ (default) - The ALERT# pin is active low and open drain.
Bit 5 - BLK_PWR_CTRL - Determines whether the device will reduce power consumption while waiting between conversion
time completion and the end of the polling cycle.
• ‘0’ (default) - The device will always power down as much as possible during the time between the end of the last
conversion and the end of the polling cycle.
• ‘1’ - The device will not power down the Cap Sensor during the time between the end of the last conversion and
the end of the polling cycle.
Bit 4 - BLK_POL_MIR - Determines whether the LED Mirror Control register bits are linked to the LED Polarity bits. Setting
this bit blocks the normal behavior which is to automatically set and clear the LED Mirror Control bits when the LED
Polarity bits are set or cleared.
• ‘0’ (default) - When the LED Polarity controls are set, the corresponding LED Mirror control is automatically set.
Likewise, when the LED Polarity controls are cleared, the corresponding LED Mirror control is also cleared.
• ‘1’ - When the LED Polarity controls are set, the corresponding LED Mirror control is not automatically set.
Bit 3 - SHOW_RF_NOISE - Determines whether the Noise Status bits will show RF Noise as the only input source.
• ‘0’ (default) - The Noise Status registers will show both RF noise and low frequency EMI noise if either is detected
on a capacitive touch sensor input.
• ‘1’ - The Noise Status registers will only show RF noise if it is detected on a capacitive touch sensor input. EMI
noise will still be detected and touches will be blocked normally; however, the status bits will not be updated.
Bit 2 - DIS_RF_NOISE - Determines whether the RF noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If RF noise is detected by the analog block, the delta count on the corresponding channel is set to 0.
Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if RF noise is detected.
Bit 0 - INT_REL_n - Controls the interrupt behavior when a release is detected on a button.
• ‘0’ (default) - An interrupt is generated when a press is detected and again when a release is detected and at the
repeat rate (if enabled - see Section 6.13).
• ‘1’ - An interrupt is generated when a press is detected and at the repeat rate but not when a release is detected.
6.7 Sensor Input Enable Registers
The Sensor Input Enable registers determine whether a capacitive touch sensor input is included in the sampling cycle.
The length of the sampling cycle is not affected by the number of sensor inputs measured.
Bit 2 - CS3_EN - Enables the CS3 input to be included during the sampling cycle.
• ‘0’ - The CS3 input is not included in the sampling cycle.
• ‘1’ (default) - The CS3 input is included in the sampling cycle.
Bit 1 - CS2_EN - Enables the CS2 input to be included during the sampling cycle.
Bit 0 - CS1_EN - Enables the CS1 input to be included during the sampling cycle.
TABLE 6-11: SENSOR INPUT ENABLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
21h R/W Sensor Input
Enable - - - - - CS3_EN CS2_EN CS1_EN 07h
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CAP1133
6.8 Sensor Input Configuration Register
The Sensor Input Configuration Register controls timings associated with the Capacitive sensor inputs 1 - 3.
Bits 7 - 4 - MAX_DUR[3:0] - (default 1010b) - Determines the maximum time that a sensor pad is allowed to be touched
until the capacitive touch sensor input is recalibrated, as shown in Table 6-13.
Bits 3 - 0 - RPT_RATE[3:0] - (default 0100b) Determines the time duration between interrupt assertions when auto
repeat is enabled. The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-14.
TABLE 6-12: SENSOR INPUT CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
22h R/W Sensor Input
Configuration MAX_DUR[3:0] RPT_RATE[3:0] A4h
TABLE 6-13: MAX_DUR BIT DECODE
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
0 0 0 0 560ms
0 0 0 1 840ms
0 0 1 0 1120ms
0 0 1 1 1400ms
0 1 0 0 1680ms
0 1 0 1 2240ms
0 1 1 0 2800ms
1 1 1 3360ms
1 0 0 0 3920ms
1 0 0 1 4480ms
1 0 1 0 5600ms (default)
1 0 1 1 6720ms
1 1 0 0 7840ms
1 1 0 1 8906ms
1 1 1 0 10080ms
1 1 1 1 11200ms
TABLE 6-14: RPT_RATE BIT DECODE
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms (default)
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
CAP1133
DS00001625B-page 28 2015 Microchip Technology Inc.
6.9 Sensor Input Configuration 2 Register
Bits 3 - 0 - M_PRESS[3:0] - (default 0111b) - Determines the minimum amount of time that sensor inputs configured to
use auto repeat must detect a sensor pad touch to detect a “press and hold” event. If the sensor input detects a touch
for longer than the M_PRESS[3:0] settings, a “press and hold” event is detected. If a sensor input detects a touch for
less than or equal to the M_PRESS[3:0] settings, a touch event is detected.
The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-16.
6.10 Averaging and Sampling Configuration Register
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-15: SENSOR INPUT CONFIGURATION 2 REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
23h R/W Sensor Input
Configuration 2 - - - - M_PRESS[3:0] 07h
TABLE 6-16: M_PRESS BIT DECODE
M_PRESS[3:0]
M_PRESS SETTINGS
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms (default)
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-17: AVERAGING AND SAMPLING CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
24h R/W Averaging and
Sampling Config AVG[2:0] SAMP_TIME[1:0] CYCLE_TIME
[1:0] 39h
TABLE 6-14: RPT_RATE BIT DECODE (CONTINUED)
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
2015 Microchip Technology Inc. DS00001625B-page 29
CAP1133
The Averaging and Sampling Configuration register controls the number of samples taken and the total sensor input
cycle time for all active sensor inputs while the device is functioning in Active state.
Bits 6 - 4 - AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor cycle
as shown in Table 6-18. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
For example, if CS1, CS2, and CS3 are sampled during the sensor cycle, and the AVG[2:0] bits are set to take 4 samples
per channel, then the full sensor cycle will be: CS1, CS1, CS1, CS1, CS2, CS2, CS2, CS2, CS3, CS3, CS3, CS3.
Bits 3 - 2 - SAMP_TIME[1:0] - Determines the time to take a single sample as shown in Table 6-19.
Bits 1 - 0 - CYCLE_TIME[1:0] - Determines the overall cycle time for all measured channels during normal operation as
shown in Table 6-20. All measured channels are sampled at the beginning of the cycle time. If additional time is remaining,
then the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The AVG[2:0] bits will take priority so that if more samples
are required than would normally be allowed during the cycle time, the cycle time will be
extended as necessary to accommodate the number of samples to be measured.
TABLE 6-18: AVG BIT DECODE
AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-19: SAMP_TIME BIT DECODE
SAMP_TIME[1:0]
Sample Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-20: CYCLE_TIME BIT DECODE
CYCLE_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
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DS00001625B-page 30 2015 Microchip Technology Inc.
6.11 Calibration Activate Register
The Calibration Activate register forces the respective sensor inputs to be re-calibrated affecting both the analog and
digital blocks. During the re-calibration routine, the sensor inputs will not detect a press for up to 600ms and the Sensor
Input Base Count register values will be invalid. During this time, any press on the corresponding sensor pads will invalidate
the re-calibration. When finished, the CALX[9:0] bits will be updated (see Section 6.39).
When the corresponding bit is set, the device will perform the calibration and the bit will be automatically cleared once
the re-calibration routine has finished.
Bit 2 - CS3_CAL - When set, the CS3 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 1 - CS2_CAL - When set, the CS2 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 0 - CS1_CAL - When set, the CS1 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
6.12 Interrupt Enable Register
The Interrupt Enable register determines whether a sensor pad touch or release (if enabled) causes the interrupt pin to
be asserted.
Bit 2 - CS3_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS3 (associated with the CS3
status bit).
• ‘0’ - The interrupt pin will not be asserted if a touch is detected on CS3 (associated with the CS6 status bit).
• ‘1’ (default) - The interrupt pin will be asserted if a touch is detected on CS3 (associated with the CS6 status bit).
Bit 1 - CS2_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS2 (associated with the CS2
status bit).
Bit 0 - CS1_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS1 (associated with the CS1
status bit).
6.13 Repeat Rate Enable Register
The Repeat Rate Enable register enables the repeat rate of the sensor inputs as described in Section 5.4.1.
Bit 2 - CS3_RPT_EN - Enables the repeat rate for capacitive touch sensor input 3.
• ‘0’ - The repeat rate for CS3 is disabled. It will only generate an interrupt when a touch is detected and when a
release is detected no matter how long the touch is held for.
• ‘1’ (default) - The repeat rate for CS3 is enabled. In the case of a “touch” event, it will generate an interrupt when a
touch is detected and a release is detected (as determined by the INT_REL_n bit - see Section 6.6). In the case of
a “press and hold” event, it will generate an interrupt when a touch is detected and at the repeat rate so long as
TABLE 6-21: CALIBRATION ACTIVATE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
26h R/W Calibration
Activate --- CS3_
CAL
CS2_
CAL
CS1_
CAL 00h
TABLE 6-22: INTERRUPT ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
27h R/W Interrupt
Enable --- CS3_
INT_EN
CS2_
INT_EN
CS1_
INT_EN 07h
TABLE 6-23: REPEAT RATE ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
28h R/W Repeat Rate
Enable ---- - CS3_
RPT_EN
CS2_
RPT_EN
CS1_
RPT_EN 07h
2015 Microchip Technology Inc. DS00001625B-page 31
CAP1133
the touch is held d.
Bit 1 - CS2_RPT_EN - Enables the repeat rate for capacitive touch sensor input 2.
Bit 0 - CS1_RPT_EN - Enables the repeat rate for capacitive touch sensor input 1.
6.14 Multiple Touch Configuration Register
The Multiple Touch Configuration register controls the settings for the multiple touch detection circuitry. These settings
determine the number of simultaneous buttons that may be pressed before additional buttons are blocked and the MULT
status bit is set.
Bit 7 - MULT_BLK_EN - Enables the multiple button blocking circuitry.
• ‘0’ - The multiple touch circuitry is disabled. The device will not block multiple touches.
• ‘1’ (default) - The multiple touch circuitry is enabled. The device will flag the number of touches equal to programmed
multiple touch threshold and block all others. It will remember which sensor inputs are valid and block all
others until that sensor pad has been released. Once a sensor pad has been released, the N detected touches
(determined via the cycle order of CS1 - CS3) will be flagged and all others blocked.
Bits 3 - 2 - B_MULT_T[1:0] - Determines the number of simultaneous touches on all sensor pads before a Multiple Touch
Event is detected and sensor inputs are blocked. The bit decode is given by Table 6-25.
6.15 Multiple Touch Pattern Configuration Register
The Multiple Touch Pattern Configuration register controls the settings for the multiple touch pattern detection circuitry.
This circuitry works like the multiple touch detection circuitry with the following differences:
1. The detection threshold is a percentage of the touch detection threshold as defined by the MTP_TH[1:0] bits
whereas the multiple touch circuitry uses the touch detection threshold.
2. The MTP detection circuitry either will detect a specific pattern of sensor inputs as determined by the Multiple
Touch Pattern register settings or it will use the Multiple Touch Pattern register settings to determine a minimum
number of sensor inputs that will cause the MTP circuitry to flag an event. When using pattern recognition mode,
if all of the sensor inputs set by the Multiple Touch Pattern register have a delta count greater than the MTP
threshold or have their corresponding Noise Flag Status bits set, the MTP bit will be set. When using the absolute
number mode, if the number of sensor inputs with thresholds above the MTP threshold or with Noise Flag Status
bits set is equal to or greater than this number, the MTP bit will be set.
3. When an MTP event occurs, all touches are blocked and an interrupt is generated.
TABLE 6-24: MULTIPLE TOUCH CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Ah R/W Multiple Touch
Config
MULT_
BLK_
EN
- - - B_MULT_T[1:0] - - 80h
TABLE 6-25: B_MULT_T BIT DECODE
B_MULT_T[1:0]
Number of Simultaneous Touches
1 0
0 0 1 (default)
01 2
10 3
11 3
TABLE 6-26: MULTIPLE TOUCH PATTERN CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Bh R/W Multiple Touch
Pattern Config MTP_ EN - - MTP_TH[1:0] COMP_
PTRN
MTP_
ALERT 00h
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DS00001625B-page 32 2015 Microchip Technology Inc.
4. All sensor inputs will remain blocked so long as the requisite number of sensor inputs are above the MTP threshold
or have Noise Flag Status bits set. Once this condition is removed, touch detection will be restored. Note that
the MTP status bit is only cleared by writing a ‘0’ to the INT bit once the condition has been removed.
Bit 7 - MTP_EN - Enables the multiple touch pattern detection circuitry.
• ‘0’ (default) - The MTP detection circuitry is disabled.
• ‘1’ - The MTP detection circuitry is enabled.
Bits 3-2 - MTP_TH[1:0] - Determine the MTP threshold, as shown in Table 6-27. This threshold is a percentage of sensor
input threshold (see Section 6.18, "Sensor Input Threshold Registers") when the device is in the Fully Active state or of
the standby threshold (see Section 6.23, "Standby Threshold Register") when the device is in the Standby state.
Bit 1 - COMP_PTRN - Determines whether the MTP detection circuitry will use the Multiple Touch Pattern register as a
specific pattern of sensor inputs or as an absolute number of sensor inputs.
• ‘0’ (default) - The MTP detection circuitry will use the Multiple Touch Pattern register bit settings as an absolute
minimum number of sensor inputs that must be above the threshold or have Noise Flag Status bits set. The number
will be equal to the number of bits set in the register.
• ‘1’ - The MTP detection circuitry will use pattern recognition. Each bit set in the Multiple Touch Pattern register
indicates a specific sensor input that must have a delta count greater than the MTP threshold or have a Noise Flag
Status bit set. If the criteria are met, the MTP status bit will be set.
Bit 0 - MTP_ALERT - Enables an interrupt if an MTP event occurs. In either condition, the MTP status bit will be set.
• ‘0’ (default) - If an MTP event occurs, the ALERT# pin is not asserted.
• ‘1’ - If an MTP event occurs, the ALERT# pin will be asserted.
6.16 Multiple Touch Pattern Register
The Multiple Touch Pattern register acts as a pattern to identify an expected sensor input profile for diagnostics or other
significant events. There are two methods for how the Multiple Touch Pattern register is used: as specific sensor inputs
or number of sensor input that must exceed the MTP threshold or have Noise Flag Status bits set. Which method is used
is based on the COMP_PTRN bit (see Section 6.15). The methods are described below.
1. Specific Sensor Inputs: If, during a single polling cycle, the specific sensor inputs above the MTP threshold or
with Noise Flag Status bits set match those bits set in the Multiple Touch Pattern register, an MTP event is
flagged.
2. Number of Sensor Inputs: If, during a single polling cycle, the number of sensor inputs with a delta count above
the MTP threshold or with Noise Flag Status bits set is equal to or greater than the number of pattern bits set, an
MTP event is flagged.
Bit 2 - CS3_PTRN - Determines whether CS3 is considered as part of the Multiple Touch Pattern.
• ‘0’ - CS3 is not considered a part of the pattern.
• ‘1’ - CS3 is considered a part of the pattern or the absolute number of sensor inputs that must have a delta count
greater than the MTP threshold or have the Noise Flag Status bit set is increased by 1.
TABLE 6-27: MTP_TH BIT DECODE
MTP_TH[1:0]
Threshold Divide Setting
1 0
0 0 12.5% (default)
0 1 25%
1 0 37.5%
1 1 100%
TABLE 6-28: MULTIPLE TOUCH PATTERN REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Dh R/W Multiple
Touch Pattern --- CS3_
PTRN
CS2_
PTRN
CS1_
PTRN 07h
2015 Microchip Technology Inc. DS00001625B-page 33
CAP1133
Bit 1 - CS2_PTRN - Determines whether CS2 is considered as part of the Multiple Touch Pattern.
Bit 0 - CS1_PTRN - Determines whether CS1 is considered as part of the Multiple Touch Pattern.
6.17 Recalibration Configuration Register
The Recalibration Configuration register controls the automatic re-calibration routine settings as well as advanced controls
to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor Input 1 Threshold
register.
• ‘0’ - Each Sensor Input X Threshold register is updated individually.
• ‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor Input Threshold
registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input Threshold 3). The individual Sensor
Input X Threshold registers (Sensor Input 2 Threshold and Sensor Input 3 Threshold) can be individually updated
at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise status bit is set.
• ‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
• ‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if the noise status bit
is set.
• ‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
• ‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to trigger a digital recalibration
as shown in Table 6-30.
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-calibration routine.
The settings apply to all sensor inputs universally (though individual sensor inputs can be configured to support re-calibration
- see Section 6.11).
TABLE 6-29: RECALIBRATION CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Fh R/W Recalibration
Configuration
BUT_
LD_TH
NO_
CLR_
INTD
NO_
CLR_
NEG
NEG_DELTA_
CNT[1:0] CAL_CFG[2:0] 8Ah
TABLE 6-30: NEG_DELTA_CNT BIT DECODE
NEG_DELTA_CNT[1:0]
Number of Consecutive Negative Delta Count Values
1 0
00 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
TABLE 6-31: CAL_CFG BIT DECODE
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
0 0 0 16 16
0 0 1 32 32
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DS00001625B-page 34 2015 Microchip Technology Inc.
Note 6-1 Recalibration Samples refers to the number of samples that are measured and averaged before the
Base Count is updated however does not control the base count update period.
Note 6-2 Update Time refers to the amount of time (in polling cycle periods) that elapses before the Base
Count is updated. The time will depend upon the number of channels active, the averaging setting,
and the programmed cycle time.
6.18 Sensor Input Threshold Registers
The Sensor Input Threshold registers store the delta threshold that is used to determine if a touch has been detected.
When a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with
a touch. If the sensor input change exceeds the threshold settings, a touch is detected.
When the BUT_LD_TH bit is set (see Section 6.17 - bit 7), writing data to the Sensor Input 1 Threshold register will
update all of the sensor input threshold registers (31h - 32h inclusive).
6.19 Sensor Input Noise Threshold Register
The Sensor Input Noise Threshold register controls the value of a secondary internal threshold to detect noise and
improve the automatic recalibration routine. If a capacitive touch sensor input exceeds the Sensor Input Noise Threshold
but does not exceed the sensor input threshold, it is determined to be caused by a noise spike. That sample is not used
by the automatic re-calibration routine. This feature can be disabled by setting the DIS_DIG_NOISE bit.
Bits 1-0 - CS1_BN_TH[1:0] - Controls the noise threshold for all capacitive touch sensor inputs, as shown in Table 6-34.
The threshold is proportional to the threshold setting.
0 1 0 64 64 (default)
0 1 1 128 128
1 0 0 256 256
1 0 1 256 1024
1 1 0 256 2048
1 1 1 256 4096
TABLE 6-32: SENSOR INPUT THRESHOLD REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
30h R/W Sensor Input 1
Threshold - 64 32 16 8 4 2 1 40h
31h R/W Sensor Input 2
Threshold - 64 32 16 8 4 2 1 40h
32h R/W Sensor Input 3
Threshold - 64 32 16 8 4 2 1 40h
TABLE 6-33: SENSOR INPUT NOISE THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
38h R/W Sensor Input
Noise Threshold CS_BN_TH [1:0] 01h
TABLE 6-31: CAL_CFG BIT DECODE (CONTINUED)
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
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CAP1133
6.20 Standby Channel Register
The Standby Channel register controls which (if any) capacitive touch sensor inputs are active during Standby.
Bit 2 - CS3_STBY - Controls whether the CS3 channel is active in Standby.
• ‘0’ (default) - The CS3 channel not be sampled during Standby mode.
• ‘1’ - The CS3 channel will be sampled during Standby Mode. It will use the Standby threshold setting, and the
standby averaging and sensitivity settings.
Bit 1 - CS2_STBY - Controls whether the CS2 channel is active in Standby.
Bit 0 - CS1_STBY - Controls whether the CS1 channel is active in Standby.
6.21 Standby Configuration Register
The Standby Configuration register controls averaging and cycle time for those sensor inputs that are active in Standby.
This register is useful for detecting proximity on a small number of sensor inputs as it allows the user to change averaging
and sample times on a limited number of sensor inputs and still maintain normal functionality in the fully active
state.
Bit 7 - AVG_SUM - Determines whether the active sensor inputs will average the programmed number of samples or
whether they will accumulate for the programmed number of samples.
• ‘0’ - (default) - The active sensor input delta count values will be based on the average of the programmed number
of samples when compared against the threshold.
• ‘1’ - The active sensor input delta count values will be based on the summation of the programmed number of
samples when compared against the threshold. This bit should only be set when performing proximity detection as
a physical touch will overflow the delta count registers and may result in false readings.
Bits 6 - 4 - STBY_AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor
cycle as shown in Table 6-37. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
TABLE 6-34: CSX_BN_TH BIT DECODE
CS_BN_TH[1:0]
Percent Threshold Setting
1 0
0 0 25%
0 1 37.5% (default)
1 0 50%
1 1 62.5%
TABLE 6-35: STANDBY CHANNEL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
40h R/W Standby Channel - - - - - CS3_
STBY
CS2_
STBY
CS1_
STBY 00h
TABLE 6-36: STANDBY CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
41h R/W Standby Configuration
AVG_
SUM STBY_AVG[2:0] STBY_SAMP_
TIME[1:0]
STBY_CY_TIME
[1:0] 39h
TABLE 6-37: STBY_AVG BIT DECODE
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
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DS00001625B-page 36 2015 Microchip Technology Inc.
Bit 3-2 - STBY SAMP_TIME[1:0] - Determines the time to take a single sample when the device is in Standby as shown
in Table 6-38.
Bits 1 - 0 - STBY_CY_TIME[2:0] - Determines the overall cycle time for all measured channels during standby operation
as shown in Table 6-39. All measured channels are sampled at the beginning of the cycle time. If additional time is
remaining, the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The STBY_AVG[2:0] bits will take priority so that if more
samples are required than would normally be allowed during the cycle time, the cycle time
will be extended as necessary to accommodate the number of samples to be measured.
6.22 Standby Sensitivity Register
The Standby Sensitivity register controls the sensitivity for sensor inputs that are active in Standby.
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-38: STBY_SAMP_TIME BIT DECODE
STBY_SAMP_TIME[1:0]
Sampling Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-39: STBY_CY_TIME BIT DECODE
STBY_CY_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-40: STANDBY SENSITIVITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
42h R/W Standby Sensitivity
- - - - - STBY_SENSE[2:0] 02h
TABLE 6-37: STBY_AVG BIT DECODE (CONTINUED)
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
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Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensor inputs that are active in Standby. The sensitivity settings
act to scale the relative delta count value higher or lower based on the system parameters. A setting of 000b is the
most sensitive while a setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a
smaller delta C corresponding to a “lighter” touch. These settings are more sensitive to noise however and a noisy environment
may flag more false touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
6.23 Standby Threshold Register
The Standby Threshold register stores the delta threshold that is used to determine if a touch has been detected. When
a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with a
touch. If the sensor input change exceeds the threshold settings, a touch is detected.
6.24 Sensor Input Base Count Registers
The Sensor Input Base Count registers store the calibrated “Not Touched” input value from the capacitive touch sensor
inputs. These registers are periodically updated by the re-calibration routine.
The routine uses an internal adder to add the current count value for each reading to the sum of the previous readings
until sample size has been reached. At this point, the upper 16 bits are taken and used as the Sensor Input Base Count.
The internal adder is then reset and the re-calibration routine continues.
TABLE 6-41: STBY_SENSE BIT DECODE
STBY_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-42: STANDBY THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
43h R/W Standby Threshold
- 64 32 16 8 4 2 1 40h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
50h R Sensor Input 1
Base Count 128 64 32 16 8 4 2 1 C8h
51h R Sensor Input 2
Base Count 128 64 32 16 8 4 2 1 C8h
52h R Sensor Input 3
Base Count 128 64 32 16 8 4 2 1 C8h
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The data presented is determined by the BASE_SHIFT[3:0] bits (see Section 6.5).
6.25 LED Output Type Register
The LED Output Type register controls the type of output for the LED pins. Each pin is controlled by a single bit. Refer
to application note 21.4 CAP1133Family LED Configuration Options for more information about implementing LEDs.
Bit 2 - LED3_OT - Determines the output type of the LED3 pin.
• ‘0’ (default) - The LED3 pin is an open-drain output with an external pull-up resistor. When the appropriate pin is
set to the “active” state (logic ‘1’), the pin will be driven low. Conversely, when the pin is set to the “inactive” state
(logic ‘0’), the pin will be left in a High Z state and pulled high via an external pull-up resistor.
• ‘1’ - The LED3 pin is a push-pull output. When driving a logic ‘1’, the pin is driven high. When driving a logic ‘0’, the
pin is driven low.
Bit 1 - LED2_OT - Determines the output type of the LED2 pin.
Bit 0 - LED1_OT - Determines the output type of the LED1 pin.
6.26 Sensor Input LED Linking Register
The Sensor Input LED Linking register controls whether a capacitive touch sensor input is linked to an LED output. If
the corresponding bit is set, then the appropriate LED output will change states defined by the LED Behavior controls
(see Section 6.31) in response to the capacitive touch sensor input.
Bit 2 - CS3_LED3 - Links the LED3 output to a detected touch on the CS3 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
• ‘0’ (default) - The LED 3 output is not associated with the CS3 input. If a touch is detected on the CS3 input, the
LED will not automatically be actuated. The LED is enabled and controlled via the LED Output Control register
(see Section 6.28) and the LED Behavior registers (see Section 6.31).
• ‘1’ - The LED 3 output is associated with the CS3 input. If a touch is detected on the CS3 input, the LED will be
actuated and behave as defined in Table 6-52.
Bit 1 - CS2_LED2 - Links the LED2 output to a detected touch on the CS2 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
Bit 0 - CS1_LED1 - Links the LED1 output to a detected touch on the CS1 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
6.27 LED Polarity Register
TABLE 6-44: LED OUTPUT TYPE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
71h R/W LED Output
Type ----- LED3_
OT
LED2_
OT
LED1_
OT 00h
TABLE 6-45: SENSOR INPUT LED LINKING REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
72h R/W Sensor Input
LED Linking
- - - - - CS3_
LED3
CS2_
LED2
CS1_
LED1
00h
TABLE 6-46: LED POLARITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
73h R/W LED Polarity - - - - - LED3_
POL
LED2_
POL
LED1_
POL 00h
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The LED Polarity register controls the logical polarity of the LED outputs. When these bits are set or cleared, the corresponding
LED Mirror controls are also set or cleared (unless the BLK_POL_MIR bit is set - see Section 6.6, "Configuration
Registers"). Table 6-48, "LED Polarity Behavior" shows the interaction between the polarity controls, output
controls, and relative brightness.
APPLICATION NOTE: The polarity controls determine the final LED pin drive. A touch on a linked capacitive touch
sensor input is treated in the same way as the LED Output Control bit being set to a logic ‘1’.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’ then the LED will be on and that the CAP1133 LED pin is sinking the LED current.
Conversely, if the LED pin is driven to a logic ‘1’, the LED will be off and there is no current
flow. See Figure 5-1, "System Diagram for CAP1133".
APPLICATION NOTE: This application note applies when the LED polarity is inverted (LEDx_POL = ‘0’). For LED
operation, the duty cycle settings determine the % of time that the LED pin will be driven to
a logic ‘0’ state in. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven low (i.e. maximum % of time that the LED is on) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven low (i.e. minimum
% of time that the LED is on). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at the minimum duty cycle setting.
Breathe operations will ramp the duty cycle from the minimum duty cycle to the maximum
duty cycle.
APPLICATION NOTE: This application note applies when the LED polarity is non-inverted (LEDx_POL = ‘1’). For
LED operation, the duty cycle settings determine the % of time that the LED pin will be driven
to a logic ‘1’ state. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven high (i.e. maximum % of time that the LED is off) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven high (i.e. minimum
% of time that the LED is off). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at 100 minus the minimum duty
cycle setting. Breathe operations will ramp the duty cycle from 100 minus the minimum duty
cycle to 100 minus the maximum duty cycle.
APPLICATION NOTE: The LED Mirror controls (see Section 6.30, "LED Mirror Control Register") work with the
polarity controls with respect to LED brightness but will not have a direct effect on the output
pin drive.
Bit 2 - LED3_POL - Determines the polarity of the LED3 output.
• ‘0’ (default) - The LED3 output is inverted. For example, a setting of ‘1’ in the LED Output Control register will
cause the LED pin output to be driven to a logic ‘0’.
• ‘1’ - The LED3 output is non-inverted. For example, a setting of ‘1’ in the LED Output Control register will cause
the LED pin output to be driven to a logic ‘1’ or left in the high-z state as determined by its output type
Bit 1 - LED2_POL - Determines the polarity of the LED2 output.
Bit 0 - LED1_POL - Determines the polarity of the LED1 output.
6.28 LED Output Control Register
The LED Output Control Register controls the output state of the LED pins that are not linked to sensor inputs.
TABLE 6-47: LED OUTPUT CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
74h R/W LED Output
Control ----- LED3_
DR
LED2_
DR
LED1_
DR 00h
Note: If an LED is linked to a sensor input in the Sensor Input LED Linking Register (Section 6.26, "Sensor Input
LED Linking Register"), the corresponding bit in the LED Output Control Register is ignored (i.e. a linked
LED cannot be host controlled).
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DS00001625B-page 40 2015 Microchip Technology Inc.
The LED Polarity Control Register will determine the non actuated state of the LED pins. The actuated LED behavior is
determined by the LED behavior controls (see Section 6.31, "LED Behavior Register").
Table 6-48 shows the interaction between the polarity controls, output controls, and relative brightness.
Bit 2 - LED3_DR - Determines whether LED3 output is driven high or low.
• ‘0’ (default) - The LED3 output is driven at the minimum duty cycle or not actuated.
• ‘1’ - The LED3 output is driven at the maximum duty cycle or is actuated.
Bit 1 - LED2_DR - Determines whether LED2 output is driven high or low.
Bit 0 - LED1_DR - Determines whether LED1 output is driven high or low.
6.29 Linked LED Transition Control Register
The Linked LED Transition Control register controls the LED drive when the LED is linked to a capacitive touch sensor
input. These controls work in conjunction with the INV_LINK_TRAN bit (see Section 6.6.2, "Configuration 2 - 44h") to
create smooth transitions from host control to linked LEDs.
Bit 2 - LED3_LTRAN - Determines the transition effect when LED3 is linked to CS3.
• ‘0’ (default) - When the LED output control bit for LED3 is ‘1’, and then LED3 is linked to CS3 and no touch is
detected, the LED will change states.
• ‘1’ - If the INV_LINK_TRAN bit is ‘1’, when the LED output control bit for CS3 is ‘1’, and then CS3 is linked to LED3
and no touch is detected, the LED will not change states. In addition, the LED state will change when the sensor
pad is touched. If the INV_LINK_TRAN bit is ‘0’, when the LED output control bit for CS3 is ‘1’, and then CS3 is
linked to LED3 and no touch is detected, the LED will not change states. However, the LED state will not change
TABLE 6-48: LED POLARITY BEHAVIOR
LED Output
Control
Register or
Touch
Polarity Max Duty Min Duty Brightness LED Appearance
0 inverted (‘0’) not used
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
min duty cycle
on at min duty
cycle
1 inverted (‘0’)
maximum % of time
that the LED is on
(logic 0)
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
max duty cycle. Brightness
ramps from min
duty cycle to max duty
cycle
according to LED
behavior
0 non-inverted
(‘1’) not used
minimum % of time
that the LED is off
(logic 1)
maximum brightness at
100 minus min duty
cycle.
on at 100 - min
duty cycle
1 non-inverted
(‘1’)
maximum % of time
that the LED is off
(logic 1)
minimum % of time
that the LED is off
(logic 1)
For Direct behavior,
maximum brightness is
100 minus max duty
cycle. When breathing,
max brightness is
100 minus min duty
cycle. Brightness
ramps from 100 - min
duty cycle to 100 - max
duty cycle.
according to LED
behavior
TABLE 6-49: LINKED LED TRANSITION CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
77h R/W Linked LED Transition
Control - ---- LED3_
LTRAN
LED2_
LTRAN
LED1_
LTRAN 00h
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when the sensor pad is touched.
APPLICATION NOTE: If the LED behavior is not “Direct” and the INV_LINK_TRAN bit it ‘0’, the LED will not perform
as expected when the LED3_LTRAN bit is set to ‘1’. Therefore, if breathe and pulse
behaviors are used, set the INV_LINK_TRAN bit to ‘1’.
Bit 1 - LED2_LTRAN - Determines the transition effect when LED2 is linked to CS2.
Bit 0 - LED1_LTRAN - Determines the transition effect when LED1 is linked to CS1.
6.30 LED Mirror Control Register
The LED Mirror Control Registers determine the meaning of duty cycle settings when polarity is non-inverted for each
LED channel. When the polarity bit is set to ‘1’ (non-inverted), to obtain correct steps for LED ramping, pulse, and
breathe behaviors, the min and max duty cycles need to be relative to 100%, rather than the default, which is relative
to 0%.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’, the LED will be on and the CAP1133 LED pin is sinking the LED current. When
the polarity bit is set to ‘1’, it is considered non-inverted. For systems using the opposite LED
configuration, mirror controls would apply when the polarity bit is ‘0’.
These bits are changed automatically if the corresponding LED Polarity bit is changed (unless the BLK_POL_MIR bit is
set - see Section 6.6).
Bit 2 - LED3_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
• ‘0’ (default) - The duty cycle settings are determined relative to 0% and are determined directly with the settings.
• ‘1’ - The duty cycle settings are determined relative to 100%.
Bit 1 - LED2_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
Bit 0 - LED1_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
6.31 LED Behavior Register
The LED Behavior register controls the operation of LEDs. Each LED pin is controlled by a 2-bit field and the behavior
is determined by whether the LED is linked to a capacitive touch sensor input or not.
If the corresponding LED output is linked to a capacitive touch sensor input, the appropriate behavior will be enabled /
disabled based on touches and releases.
If the LED output is not associated with a capacitive touch sensor input, the appropriate behavior will be enabled / disabled
by the LED Output Control register. If the respective LEDx_DR bit is set to a logic ‘1’, this will be associated as a
“touch”, and if the LEDx_DR bit is set to a logic ‘0’, this will be associated as a “release”.
Table 6-52, "LEDx_CTL Bit Decode" shows the behavior triggers. The defined behavior will activate when the Start Trigger
is met and will stop when the Stop Trigger is met. Note the behavior of the Breathe Hold and Pulse Release option.
The LED Polarity Control register will determine the non actuated state of the LED outputs (see Section 6.27, "LED
Polarity Register").
APPLICATION NOTE: If an LED is not linked to a capacitive touch sensor input and is breathing (via the Breathe
or Pulse behaviors), it must be unactuated and then re-actuated before changes to behavior
TABLE 6-50: LED MIRROR CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
79h R/W LED Mirror Control
-----
LED3_
MIR_
EN
LED2_
MIR _
EN
LED1_
MIR _
EN
00h
TABLE 6-51: LED BEHAVIOR REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
81h R/W LED Behavior 1 - - LED3_CTL[1:0] LED2_CTL[1:0] LED1_CTL[1:0] 00h
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DS00001625B-page 42 2015 Microchip Technology Inc.
are processed. For example, if the LED output is breathing and the Maximum duty cycle is
changed, this change will not take effect until the LED output control register is set to ‘0’ and
then re-set to ‘1’.
APPLICATION NOTE: If an LED is not linked to the capacitive touch sensor input and configured to operate using
Pulse 1 Behavior, then the circuitry will only be actuated when the corresponding output
control bit is set. It will not check the bit condition until the Pulse 1 behavior is finished. The
device will not remember if the bit was cleared and reset while it was actuated.
APPLICATION NOTE: If an LED is actuated and not linked and the desired LED behavior is changed, this new
behavior will take effect immediately; however, the first instance of the changed behavior
may act incorrectly (e.g. if changed from Direct to Pulse 1, the LED output may ‘breathe’ 4
times and then end at minimum duty cycle). LED Behaviors will operate normally once the
LED has been un-actuated and then re-actuated.
APPLICATION NOTE: If an LED is actuated and it is switched from linked to a capacitive touch sensor input to
unlinked (or vice versa), the LED will respond to the new command source immediately if
the behavior was Direct or Breathe. For Pulse behaviors, it will complete the behavior
already in progress. For example, if a linked LED was actuated by a touch and the control
is changed so that it is unlinked, it will check the status of the corresponding LED Output
Control bit. If that bit is ‘0’, then the LED will behave as if a release was detected. Likewise,
if an unlinked LED was actuated by the LED Output Control register and the control is
changed so that it is linked and no touch is detected, then the LED will behave as if a release
was detected.
Bits 5 - 4 - LED3_CTL[1:0] - Determines the behavior of LED3 as shown in Table 6-52.
Bits 3 - 2 - LED2_CTL[1:0] - Determines the behavior of LED2 as shown in Table 6-52.
Bits 1 - 0 - LED1_CTL[1:0] - Determines the behavior of LED1 as shown in Table 6-52.
TABLE 6-52: LEDX_CTL BIT DECODE
LEDx_CTL
[1:0] Operation Description Start TRigger Stop Trigger
1 0
0 0 Direct The LED is driven to the programmed state
(active or inactive). See Figure 6-7
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
0 1 Pulse 1
The LED will “Pulse” a programmed number
of times. During each “Pulse” the LED will
breathe up to the maximum brightness and
back down to the minimum brightness so that
the total “Pulse” period matches the programmed
value.
Touch or Release
Detected or LED
Output Control bit
set or cleared
(see Section 6.32)
n/a
1 0 Pulse 2
The LED will “Pulse” when the start trigger is
detected. When the stop trigger is detected, it
will “Pulse” a programmable number of times
then return to its minimum brightness.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
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APPLICATION NOTE: The PWM frequency is determined based on the selected LED behavior, the programmed
breathe period, and the programmed min and max duty cycles. For the Direct behavior
mode, the PWM frequency is calculated based on the programmed Rise and Fall times. If
these are set at 0, then the maximum PWM frequency will be used based on the
programmed duty cycle settings.
6.32 LED Pulse 1 Period Register
The LED Pulse Period 1 register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 01b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms (24 x 32ms = 768ms). The total range is from 32ms to 4.064 seconds as shown in Table 6-54 with the
default being 1024ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
Bit 7 - ST_TRIG - Determines the start trigger for the LED Pulse behavior.
• ‘0’ (default) - The LED will Pulse when a touch is detected or the drive bit is set.
• ‘1’ - The LED will Pulse when a release is detected or the drive bit is cleared.
The Pulse 1 operation is shown in Figure 6-1 when the LED output is configured for non-inverted polarity (LEDx_POL
= 1) and in Figure 6-2 for inverted polarity (LEDx_POL = 0).
1 1 Breathe
The LED will breathe. It will be driven with a
duty cycle that ramps up from the programmed
minimum duty cycle (default 0%) to
the programmed maximum duty cycle duty
cycle (default 100%) and then back down.
Each ramp takes up 50% of the programmed
period. The total period of each “breath” is
determined by the LED Breathe Period controls
- see Section 6.34.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
TABLE 6-53: LED PULSE 1 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
84h R/W LED Pulse 1
Period
ST_
TRIG
P1_
PER6
P1_
PER5
P1_
PER4
P1_
PER3
P1_
PER2
P1_
PER1
P1_
PER0 20h
TABLE 6-52: LEDX_CTL BIT DECODE (CONTINUED)
LEDx_CTL
[1:0] Operation Description Start TRigger Stop Trigger
1 0
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.
FIGURE 6-1: Pulse 1 Behavior with Non-Inverted Polarity
FIGURE 6-2: Pulse 1 Behavior with Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
00h 0 32
01h 1 32
02h 2 64
03h 3 96
. . . . . . . . .
7Dh 125 4000
7Eh 126 4032
7Fh 127 4064
Normal – untouched
operation Normal – untouched
operation
Touch Detected or
Release Detected
(100% - Pulse 1 Max Duty Cycle) * Brightness
X pulses after touch or after release
Pulse 1 Period
(P1_PER)
(100% - Pulse 1 Min Duty Cycle) * Brightness
LED
Brightness
Normal – untouched
operation
Normal – untouched
operation
Touch Detected or
Release Detected
Pulse 1 Min Duty Cycle * Brightness
X pulses after touch or after release
Pulse Period
(P1_PER)
Pulse 1 Max Duty Cycle * Brightness
LED
Brightness
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6.33 LED Pulse 2 Period Register
The LED Pulse 2 Period register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 10b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 640ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
The Pulse 2 Behavior is shown in Figure 6-3 for non-inverted polarity (LEDx_POL = 1) and in Figure 6-4 for inverted
polarity (LEDx_POL = 0).
TABLE 6-55: LED PULSE 2 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
85h R/W LED Pulse 2
Period - P2_
PER6
P2_
PER5
P2_
PER4
P2_
PER3
P2_
PER2
P2_
PER1
P2_
PER0 14h
FIGURE 6-3: Pulse 2 Behavior with Non-Inverted Polarity
FIGURE 6-4: Pulse 2 Behavior with Inverted Polarity
. . .
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
(100% - Pulse 2 Min Duty Cycle) *
Brightness
(100% - Pulse 2 Max Duty Cycle) * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
Pulse 2 Max Duty Cycle * Brightness
Pulse 2 Min Duty Cycle * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness . . .
CAP1133
DS00001625B-page 46 2015 Microchip Technology Inc.
6.34 LED Breathe Period Register
The LED Breathe Period register determines the overall period of a breathe operation as determined by the LED_CTL
registers (see Table 6-52 - setting 11b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 2976ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
6.35 LED Configuration Register
The LED Configuration register controls general LED behavior as well as the number of pulses that are sent for the
PULSE LED output behavior.
Bit 6 - RAMP_ALERT - Determines whether the device will assert the ALERT# pin when LEDs actuated by the LED
Output Control register bits have finished their respective behaviors. Interrupts will only be generated if the LED activity
is generated by writing the LED Output Control registers. Any LED activity associated with touch detection will not cause
an interrupt to be generated when the LED behavior has been finished.
• ‘0’ (default) - The ALERT# pin will not be asserted when LEDs actuated by the LED Output Control register have
finished their programmed behaviors.
• ‘1’ - The ALERT# pin will be asserted whenever any LED that is actuated by the LED Output Control register has
finished its programmed behavior.
Bits 5 - 3 - PULSE2_CNT[2:0] - Determines the number of pulses used for the Pulse 2 behavior as shown in Table 6-58.
Bits 2 - 0 - PULSE1_CNT[2:0] - Determines the number of pulses used for the Pulse 1 behavior as shown in Table 6-58.
TABLE 6-56: LED BREATHE PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
86h R/W LED Breathe
Period - BR_
PER6
BR_
PER5
BR_
PER4
BR_
PER3
BR_
PER2
BR_
PER1
BR_
PER0 5Dh
TABLE 6-57: LED CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
88h R/W LED Config - RAMP_
ALERT PULSE2_CNT[2:0] PULSE1_CNT[2:0] 04h
TABLE 6-58: PULSEX_CNT DECODE
PULSEX_CNT[2:0]
Number of Breaths
21 0
0 0 0 1 (default - Pulse 2)
00 1 2
01 0 3
01 1 4
1 0 0 5 (default - Pulse 1)
10 1 6
11 0 7
11 1 8
2015 Microchip Technology Inc. DS00001625B-page 47
CAP1133
6.36 LED Duty Cycle Registers
The LED Duty Cycle registers determine the minimum and maximum duty cycle settings used for the LED for each LED
behavior. These settings affect the brightness of the LED when it is fully off and fully on.
The LED driver duty cycle will ramp up from the minimum duty cycle to the maximum duty cycle and back down again.
APPLICATION NOTE: When operating in Direct behavior mode, changes to the Duty Cycle settings will be applied
immediately. When operating in Breathe, Pulse 1, or Pulse 2 modes, the LED must be
unactuated and then re-actuated before changes to behavior are processed.
Bits 7 - 4 - X_MAX_DUTY[3:0] - Determines the maximum PWM duty cycle for the LED drivers as shown in Table 6-60.
Bits 3 - 0 - X_MIN_DUTY[3:0] - Determines the minimum PWM duty cycle for the LED drivers as shown in Table 6-60.
6.37 LED Direct Ramp Rates Register
TABLE 6-59: LED DUTY CYCLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
90h R/W LED Pulse 1 Duty
Cycle P1_MAX_DUTY[3:0] P1_MIN_DUTY[3:0] F0h
91h R/W LED Pulse 2 Duty
Cycle P2_MAX_DUTY[3:0] P2_MIN_DUTY[3:0] F0h
92h R/W LED Breathe
Duty Cycle BR_MAX_DUTY[3:0] BR_MIN_DUTY[3:0] F0h
93h R/W Direct Duty Cycle DR_MAX_DUTY[3:0] DR_MIN_DUTY[3:0] F0h
TABLE 6-60: LED DUTY CYCLE DECODE
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
0 0 0 0 7% 0%
0 0 0 1 9% 7%
0 0 1 0 11% 9%
0 0 1 1 14% 11%
0 1 0 0 17% 14%
0 1 0 1 20% 17%
0 1 1 0 23% 20%
0 1 1 1 26% 23%
1 0 0 0 30% 26%
1 0 0 1 35% 30%
1 0 1 0 40% 35%
1 0 1 1 46% 40%
1 1 0 0 53% 46%
1 1 0 1 63% 53%
1 1 1 0 77% 63%
1 1 1 1 100% 77%
TABLE 6-61: LED DIRECT RAMP RATES REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
94h R/W LED Direct Ramp
Rates - - RISE_RATE[2:0] FALL_RATE[2:0] 00h
CAP1133
DS00001625B-page 48 2015 Microchip Technology Inc.
The LED Direct Ramp Rates register control the rising and falling edge time of an LED that is configured to operate in
Direct behavior mode. The rising edge time corresponds to the amount of time the LED takes to transition from its minimum
duty cycle to its maximum duty cycle. Conversely, the falling edge time corresponds to the amount of time that
the LED takes to transition from its maximum duty cycle to its minimum duty cycle.
Bits 5 - 3 - RISE_RATE[2:0] - Determines the rising edge time of an LED when it transitions from its minimum drive state
to its maximum drive state as shown in Table 6-62.
Bits 2 - 0 - FALL_RATE[2:0] - Determines the falling edge time of an LED when it transitions from its maximum drive
state to its minimum drive state as shown in Table 6-62.
6.38 LED Off Delay Register
The LED Off Delay register determines the amount of time that an LED remains at its maximum duty cycle (or minimum
as determined by the polarity controls) before it starts to ramp down. If the LED is operating in Breathe mode, this delay
is applied at the top of each “breath”. If the LED is operating in the Direct mode, this delay is applied when the LED is
unactuated.
Bits 6 - 4 - BR_OFF_DLY[2:0] - Determines the Breathe behavior mode off delay, which is the amount of time an LED
in Breathe behavior mode remains inactive after it finishes a breathe pulse (ramp on and ramp off), as shown in Figure 6-
5 (non-inverted polarity LEDx_POL = 1) and Figure 6-6 (inverted polarity LEDx_POL = 0). Available settings are shown
in Table 6-64.
TABLE 6-62: RISE / FALL RATE DECODE
RISE_RATE/ FALL_RATE/ Bit Decode
Rise / Fall Time (TRISE / TFALL)
21 0
00 0 0
0 0 1 250ms
0 1 0 500ms
0 1 1 750ms
1 0 0 1s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2s
TABLE 6-63: LED OFF DELAY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
95h R/W LED Off Delay
Register - BR_OFF_DLY[2:0] DIR_OFF_DLY[3:0] 00h
2015 Microchip Technology Inc. DS00001625B-page 49
CAP1133
FIGURE 6-5: Breathe Behavior with Non-Inverted Polarity
FIGURE 6-6: Breathe Behavior with Inverted Polarity
TABLE 6-64: BREATHE OFF DELAY SETTINGS
BR_OFF_DLY [2:0]
OFF Delay
2 10
0 0 0 0 (default)
0 0 1 0.25s
0 1 0 0.5s
0 1 1 0.75s
LED Actuated
100% - Breathe Max Min Cycle * Brightness
100% - Breathe Min Duty Cycle *
Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
LED Actuated
Breathe Max Duty Cycle * Brightness
Breathe Min Duty Cycle * Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
CAP1133
DS00001625B-page 50 2015 Microchip Technology Inc.
Bits 3 - 0 - DIR_OFF_DLY[3:0] - Determines the turn-off delay, as shown in Table 6-65, for all LEDs that are configured
to operate in Direct behavior mode.
The Direct behavior operation is determined by the combination of programmed Rise Time, Fall Time, Min and Max Duty
cycles, Off Delay, and polarity. Figure 6-7 shows the behavior for non-inverted polarity (LEDx_POL = 1) while Figure 6-
8 shows the behavior for inverted polarity (LEDx_POL = 0).
1 0 0 1.0s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2.0s
FIGURE 6-7: Direct Behavior for Non-Inverted Polarity
FIGURE 6-8: Direct Behavior for Inverted Polarity
TABLE 6-65: OFF DELAY DECODE
OFF Delay[3:0] Bit Decode
OFF Delay (tOFF_DLY)
32 1 0
00 0 0 0
0 0 0 1 250ms
0 0 1 0 500ms
0 0 1 1 750ms
TABLE 6-64: BREATHE OFF DELAY SETTINGS (CONTINUED)
BR_OFF_DLY [2:0]
OFF Delay
2 10
Normal –
untouched
operation
RISE_RATE
Setting (tRISE)
(100% - Max Duty
Cycle) * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
(100% - Min Duty Cycle) *
Brightness LED
Brightness
Normal –
untouched
operation RISE_RATE
Setting (tRISE)
Min Duty Cycle * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
Max Duty Cycle * Brightness
LED
Brightness
2015 Microchip Technology Inc. DS00001625B-page 51
CAP1133
6.39 Sensor Input Calibration Registers
The Sensor Input Calibration registers hold the 10-bit value that represents the last calibration value.
6.40 Product ID Register
The Product ID register stores a unique 8-bit value that identifies the device.
6.41 Manufacturer ID Register
The Vendor ID register stores an 8-bit value that represents Microchip.
0 1 0 0 1s
0 1 0 1 1.25s
0 1 1 0 1.5s
0 1 1 1 2s
1 0 0 0 2.5s
1 0 0 1 3.0s
1 0 1 0 3.5s
1 0 1 1 4.0s
1 1 0 0 4.5s
All others 5.0s
TABLE 6-66: SENSOR INPUT CALIBRATION REGISTERS
ADDR Register R/W B7 B6 B5 B4 B3 B2 B1 B0 Default
B1h Sensor Input 1
Calibration R CAL1_9 CAL1_8 CAL1_7 CAL1_6 CAL1_5 CAL1_4 CAL1_3 CAL1_2 00h
B2h Sensor Input 2
Calibration R CAL2_9 CAL2_8 CAL2_7 CAL2_6 CAL2_5 CAL2_4 CAL2_3 CAL2_2 00h
B3h Sensor Input 3
Calibration R CAL3_9 CAL3_8 CAL3_7 CAL3_6 CAL3_5 CAL3_4 CAL3_3 CAL3_2 00h
B9h
Sensor Input
Calibration LSB
1
R - - CAL3_1 CAL3_0 CAL2_1 CAL2_0 CAL1_1 CAL1_0 00h
TABLE 6-67: PRODUCT ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FDh R Product ID 0 1 0 1 0 1 0 0 54h
TABLE 6-68: VENDOR ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FEh R Manufacturer ID 0 1 0 1 1 1 0 1 5Dh
TABLE 6-65: OFF DELAY DECODE (CONTINUED)
OFF Delay[3:0] Bit Decode
OFF Delay (tOFF_DLY)
32 1 0
CAP1133
DS00001625B-page 52 2015 Microchip Technology Inc.
6.42 Revision Register
The Revision register stores an 8-bit value that represents the part revision.
TABLE 6-69: REVISION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FFh R Revision 1 0 0 0 0 0 1 1 83h
2015 Microchip Technology Inc. DS00001625B-page 53
CAP1133
7.0 PACKAGE INFORMATION
7.1 CAP1133 Package Drawings
FIGURE 7-1: 10-Pin DFN 3mm x 3mm Package Drawings (1 of 2)
Note: For the most current package drawings,
see the Microchip Packaging Specification at
http://www.microchip.com/packaging
CAP1133
DS00001625B-page 54 2015 Microchip Technology Inc.
FIGURE 7-2: 10-Pin DFN 3mm x 3mm Package Drawings (2 of 2)
Note: For the most current package drawings,
see the Microchip Packaging Specification at
http://www.microchip.com/packaging
2015 Microchip Technology Inc. DS00001625B-page 55
CAP1133
7.2 Package Marking
FIGURE 7-3: CAP1133 Package Marking
1 A W
NNNA
e4
TOP
BOTTOM
Bottom marking not allowed
PB-FREE/GREEN SYMBOL
PIN 1 (Ni/Pd PP-LF)
Line 1 – Device Code, Week 2x 0.6
Line 2 – Alphanumeric Traceability Code
W
Lines 1-2:
Line 3:
Center Horizontal Alignment
As Shown
CAP1133
DS00001625B-page 56 2015 Microchip Technology Inc.
APPENDIX A: DEVICE DELTA
A.1 Delta from CAP1033 to CAP1133
1. Updated circuitry to improve power supply rejection.
2. Updated LED driver duty cycle decode values to have more distribution at lower values - closer to a logarithmic
curve. See Table 6-60, "LED Duty Cycle Decode".
3. Updated bug that breathe periods were not correct above 2.6s. This includes rise / fall time decodes above 1.5s.
4. Added 1 bit to the LED Off Delay register (see Section 6.38, "LED Off Delay Register") to extend times from 2s
to 5s in 0.5s intervals.
5. Breathe behavior modified. A breathe off delay control was added to the LED Off Delay Register (see Section
6.38, "LED Off Delay Register") so the LEDs can be configured to remain inactive between breathes.
6. Added controls for the LED transition effects when linking LEDs to capacitive sensor inputs. See Section 6.29,
"Linked LED Transition Control Register".
7. Added controls to “mirror” the LED duty cycle outputs so that when polarity changes, the LED brightness levels
look right. These bits are automatically set when polarity is set. Added control to break this auto-set behavior.
See Section 6.30, "LED Mirror Control Register".
8. Added Multiple Touch Pattern detection circuitry. See Section 6.15, "Multiple Touch Pattern Configuration Register".
9. Added General Status register to flag Multiple touches, Multiple Touch Pattern issues and general touch detections.
See Section 6.2, "Status Registers".
10. Added bits 6 and 5 to the Recalibration Configuration register (2Fh - see Section 6.17, "Recalibration Configuration
Register"). These bits control whether the accumulation of intermediate data and the consecutive negative
delta counts counter are cleared when the noise status bit is set.
11. Added Configuration 2 register for LED linking controls, noise detection controls, and control to interrupt on press
but not on release. Added control to change alert pin polarity. See Section 6.6, "Configuration Registers".
12. Updated Deep Sleep behavior so that device does not clear DSLEEP bit on received communications but will
wake to communicate.
13. Changed PWM frequency for LED drivers. The PWM frequency was derived from the programmed breathe
period and duty cycle settings and it ranged from ~4Hz to ~8000 Hz. The PWM frequency has been updated to
be a fixed value of ~2000Hz.
14. Register delta:
Table A.1 Register Delta From CAP1033 to CAP1133
Address Register Delta Delta Default
00h
Page 21
Changed - Main Status /
Control
added bits 7-6 to control gain 00h
02h
Page 22
New - General Status new register to store MTP, MULT, LED, and
general TOUCH bits
00h
44h
Page 25
New - Configuration 2 new register to control alert polarity, LED
touch linking behavior, LED output behavior,
and noise detection, and interrupt on
release
40h
24h
Page 28
Changed - Averaging
Control
updated register bits - moved
SAMP_AVG[2:0] bits and added SAMP_-
TIME bit 1. Default changed
39h
2Bh
Page 31
New - Multiple Touch
Pattern Configuration
new register for Multiple Touch Pattern
configuration - enable and threshold settings
80h
2Dh
Page 32
New - Multiple Touch
Pattern Register
new register for Multiple Touch Pattern
detection circuitry - pattern or number of
sensor inputs
07h
2015 Microchip Technology Inc. DS00001625B-page 57
CAP1133
2Fh
Page 33
Changed - Recalibration
Configuration
updated register - updated CAL_CFG bit
decode to add a 128 averages setting and
removed highest time setting. Default
changed. Added bit 6 NO_CLR_INTD and
bit 5 NO_CLR_NEG.
8Ah
38h
Page 34
Changed - Sensor Input
Noise Threshold
updated register bits - removed bits 7 - 3
and consolidated all controls into bits 1 - 0.
These bits will set the noise threshold for
all channels. Default changed
01h
39h Removed - Noise
Threshold Register 2
removed register n/a
41h
Page 35
Changed - Standby Configuration
updated register bits - moved
STBY_AVG[2:0] bits and added STBY_-
TIME bit 1. Default changed
39h
77h
Page 40
New - Linked LED Transition
Control
new register to control transition effect
when LED linked to sensor inputs
00h
79h
Page 41
New - LED Mirror Control new register to control LED output mirroring
for brightness control when polarity
changed
00h
90h
Page 47
Changed - LED Pulse 1
Duty Cycle
changed bit decode to be more logarithmic F0h
91h
Page 47
Changed - LED Pulse 2
Duty Cycle
changed bit decode to be more logarithmic F0h
92h
Page 47
Changed - LED Breathe
Duty Cycle
changed bit decode to be more logarithmic F0h
93h
Page 47
Changed - LED Direct
Duty Cycle
changed bit decode to be more logarithmic F0h
95h Added controls - LED Off
Delay
Added bits 6-4 BR_OFF_DLY[2:0]
Added bit 3 DIR_OFF_DLY[3]
00h
FDh
Page 51
Changed - Product ID Changed bit decode for CAP1133 54h
Table A.1 Register Delta From CAP1033 to CAP1133 (continued)
Address Register Delta Delta Default
CAP1133
DS00001625B-page 58 2015 Microchip Technology Inc.
APPENDIX B: DATA SHEET REVISION HISTORY
Revision Section/Figure/Entry Correction
DS00001625B (02-09-15)
Features, Table 2-2, Table 2-
2, "Pin Types", Section 5.0,
"General Description"
References to BC-Link Interface, BC_DATA, BC_-
CLK, BC-IRQ#, BC-Link bus have been removed
Application Note under Table
2-6
[BC-Link] hidden in data sheet
Table 3-2, "Electrical Specifications"
BC-Link Timing Section hidden in data sheet
Table 4-1 Protocol Used for 68K Pull Down Resistor changed
from “BC-Link Communications” to “Reserved”
Section 4.2.2, "SMBus
Address and RD / WR Bit"
Replaced “client address” with “slave address” in this
section.
Section 4.2.4, SMBus ACK
and NACK Bits, Section 4.2.5,
SMBus Stop Bit,Section 4.2.7,
SMBus and I2C Compatibility
Replaced “client” with “slave” in these sections.
Table 4-3, "Read Byte Protocol"
Heading changed from “Client Address” to “Slave
Address”
Table 6-1 Register Name for Register Address 77h changed
from “LED Linked Transition Control” to “Linked LED
Transition Control”
Section 6.30 changed CS3 to LED3
Section 7.7 Package Marking Updated package drawing
Appendix A: Device Delta changed 2Dh to 2Fh in item #12
Product Identification System Removed BC-Link references
REV A REV A replaces previous SMSC version Rev. 1.32 (01-05-12)
Rev. 1.32 (01-05-12) Table 3-2, "Electrical Specifications"
Added conditions for tHD:DAT.
Section 4.2.7, "SMBus and
I2C Compatibility"
Renamed from “SMBus and I2C Compliance.”
First paragraph, added last sentence: “For information
on using the CAP1188 in an I2C system, refer to
SMSC AN 14.0 SMSC Dedicated Slave Devices in
I
2C Systems.”
Added: CAP1188 supports I2C fast mode at 400kHz.
This covers the SMBus max time of 100kHz.
Section 6.4, "Sensor Input
Delta Count Registers"
Changed negative value cap from FFh to 80h.
Rev. 1.31 (08-18-11) Section 4.3.3, "SMBus Send
Byte"
Added an application note: The Send Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit is
set).
Section 4.3.4, "SMBus
Receive Byte"
Added an application note: The Receive Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit
is set).
Section 6.2, "Status Registers"
Removed RESET as bit 3 in register 02h.
Rev. 1.3 (05-18-11) Section 6.42, "Revision Register"
Updated revision ID from 82h to 83h.
Section 6.2, "Status Registers"
Added RESET as bit 3 in register 02h.
2015 Microchip Technology Inc. DS00001625B-page 59
CAP1133
Rev. 1.2 (02-10-11) Section A.8, "Delta from Rev
B (Mask B0) to Rev C (Mask
B1)"
Added.
Table 3-2, "Electrical Specifications"
PSR improvements made in functional revision B.
Changed PSR spec from ±100 typ and ±200 max
counts / V to ±3 and ±10 counts / V. Conditions
updated.
Section 5.3.2, "Recalibrating
Sensor Inputs"
Added more detail with subheadings for each type of
recalibration.
Section 6.6, "Configuration
Registers"
Added bit 5 BLK_PWR_CTRL to the Configuration 2
Register 44h.
The TIMEOUT bit is set to ‘1’ by default for functional
revision B and is set to ‘0’ by default for functional
revision C.
Section 6.42, "Revision Register"
Updated revision ID in register FFh from 81h to 82h.
Rev. 1.1 (11-17-10) Document Updated for functional revision B. See Section A.7,
"Delta from Rev A (Mask A0) to Rev B (Mask B0)".
Cover Added to General Description: “includes circuitry and
support for enhanced sensor proximity detection.”
Added the following Features:
Calibrates for Parasitic Capacitance
Analog Filtering for System Noise Sources
Press and Hold feature for Volume-like Applications
Table 3-2, "Electrical Specifications"
Conditions for Power Supply Rejection modified adding
the following:
Sampling time = 2.56ms
Averaging = 1
Negative Delta Counts = Disabled
All other parameters default
Section 6.11, "Calibration Activate
Register"
Updated register description to indicate which re-calibration
routine is used.
Section 6.14, "Multiple Touch
Configuration Register"
Updated register description to indicate what will
happen.
Table 6-34, "CSx_BN_TH Bit
Decode"
Table heading changed from “Threshold Divide Setting”
to “Percent Threshold Setting”.
Rev. 1.0 (06-14-10) Initial release
Revision Section/Figure/Entry Correction
CAP1133
DS00001625B-page 60 2015 Microchip Technology Inc.
THE MICROCHIP WEB SITE
Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains
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To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification”
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CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
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Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://www.microchip.com/support
2015 Microchip Technology Inc. DS00001625B-page 61
CAP1133
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. [X] - [X] - XXX - [X](1)
l l l l l
Device Temperature Addressing Package Tape and Reel
Range Option Option
Example:
Note 1: Tape and Reel identifier only appears in the catalog part number description. This identifier is used for ordering
purposes and is not printed on the device package. Check with your Microchip Sales Office for package availability
with the Tape and Reel option.
Device: CAP1133
Temperature
Range:
Blank = 0°C to +85°C (Extended Commercial)
Package: AIA = DFN
Tape and
Reel Option:
TR = Tape and Reel(1)
CAP1133-1-AIA-TR
10-pin DFN 3mm x 3mm (RoHS compliant)
Three capacitive touch sensor inputs, Three
LED drivers, SMBus interface
Reel size is 4,000 pieces
CAP1133
DS00001625B-page 62 2015 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
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2015 Microchip Technology Inc. DS00001624B-page 1
General Description
The CAP1106, which incorporates RightTouch® technology,
is a multiple channel Capacitive Touch sensor.
The CAP1106 contains six (6) individual capacitive
touch sensor inputs. The device offers programmable
sensitivity for use in touch sensor applications. Each
sensor input automatically recalibrates to compensate
for gradual environmental changes.
The CAP1106 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons
to be touched simultaneously. If this pattern is
detected, then a status bit is set and an interrupt generated.
Additionally, the CAP1106 includes circuitry and support
for enhanced sensor proximity detection.
The CAP1106 offers multiple power states operating at
low quiescent currents. In the Standby state of operation,
one or more capacitive touch sensor inputs are
active.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor
inputs are active. Communications will wake the
device.
Applications
• Desktop and Notebook PCs
• LCD Monitors
• Consumer Electronics
• Appliances
Features
• Six (6) Capacitive Touch Sensor Inputs -
CAP1106
- Programmable sensitivity
- Automatic recalibration
- Individual thresholds for each button
• Proximity Detection
• Multiple Button Pattern Detection
• Calibrates for Parasitic Capacitance
• Analog Filtering for System Noise Sources
• Press and Hold feature for Volume-like Applications
• Multiple Communication Interfaces
- SMBus / I2C compliant interface
• Low Power Operation
- 5uA quiescent current in Deep Sleep
- 50uA quiescent current in Standby (1 sensor
input monitored)
- Samples one or more channels in Standby
• Available in 10-pin 3mm x 3mm RoHS compliant
DFN package
CAP1106
6 Channel Capacitive Touch Sensor
CAP1106
DS00001624B-page 2 2015 Microchip Technology Inc.
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2015 Microchip Technology Inc. DS00001624B-page 3
CAP1106
Table of Contents
1.0 Block Diagram ................................................................................................................................................................................. 4
2.0 Pin Description ................................................................................................................................................................................ 5
3.0 Electrical Specifications .................................................................................................................................................................. 9
4.0 Communications ........................................................................................................................................................................... 12
5.0 General Description ...................................................................................................................................................................... 23
6.0 Register Description ...................................................................................................................................................................... 29
7.0 Package Information ..................................................................................................................................................................... 67
Appendix A: Device Delta ................................................................................................................................................................... 72
Appendix B: Data Sheet Revision History ........................................................................................................................................... 74
The Microchip Web Site ...................................................................................................................................................................... 76
Customer Change Notification Service ............................................................................................................................................... 76
Customer Support ............................................................................................................................................................................... 76
Product Identification System ............................................................................................................................................................. 77
CAP1106
DS00001624B-page 4 2015 Microchip Technology Inc.
1.0 BLOCK DIAGRAM
SMBus /
BC-Link
Protocol
VDD GND
Capacitive Touch Sensing Algorithm
CS1 CS2 CS3 CS4 CS5
SMCLK1
/ BC_CLK2
SMDATA1
/ BC_DATA2
ALERT#1
/ BC_IRQ#2
1
= CAP1106-1
2
= CAP1106-2 CS6
2015 Microchip Technology Inc. DS00001624B-page 5
CAP1106
2.0 PIN DESCRIPTION
FIGURE 2-1: CAP1106 Pin Diagram (10-Pin DFN)
TABLE 2-1: PIN DESCRIPTION FOR CAP1106
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
1 CS1 Capacitive Touch Sensor Input 1 AIO Connect to
Ground
2 ALERT#
ALERT# - Active low alert / interrupt output for SMBus
alert OD (5V) Connect to
Ground
ALERT# - Active high alert / interrupt output for SMBus
alert DO leave open
3 SMDATA SMDATA - Bi-directional, open-drain SMBus data -
requires pull-up resistor DIOD (5V) n/a
4 SMCLK SMCLK - SMBus clock input - requires pull-up resistor DI (5V) n/a
5 VDD Positive Power supply Power n/a
6 CS6 Capacitive Touch Sensor Input 6 AIO Connect to
Ground
7 CS5 Capacitive Touch Sensor Input 5 AIO Connect to
Ground
8 CS4 Capacitive Touch Sensor Input 4 AIO Connect to
Ground
9 CS3 Capacitive Touch Sensor Input 3 AIO Connect to
Ground
GND
CS3
1 CS2
2
3
4
5
CS4
CS1
ALERT# / BC_IRQ#
SMDATA / BC_DATA
VDD
SMCLK / BC_CLK CS5
CS6
CAP1106
3mm x 3mm DFN
10
9
8
7
6
CAP1106
DS00001624B-page 6 2015 Microchip Technology Inc.
APPLICATION NOTE: When the ALERT# pin is configured as an active low output, it will be open drain. When it
is configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1106 is unpowered.
The pin types are described in Table 2-2. All pins labeled with (5V) are 5V tolerant.
10 CS2 Capacitive Touch Sensor Input 2 AIO Connect to
Ground
Bottom
Pad GND Ground Power n/a
TABLE 2-2: PIN TYPES
Pin Type Description
Power This pin is used to supply power or ground to the device.
DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
AIO Analog Input / Output -This pin is used as an I/O for analog signals.
DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output,
it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a
pull-up resistor. This pin is 5V tolerant.
DO Push-pull Digital Output - This pin is used as a digital output and can sink and source current.
DIO Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
TABLE 2-1: PIN DESCRIPTION FOR CAP1106 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
2015 Microchip Technology Inc. DS00001624B-page 7
CAP1106
3.0 ELECTRICAL SPECIFICATIONS
Note 3-1 Stresses above those listed could cause permanent damage to the device. This is a stress rating
only and functional operation of the device at any other condition above those indicated in the
operation sections of this specification is not implied.
Note 3-2 For the 5V tolerant pins that have a pull-up resistor, the voltage difference between V5VT_PIN and VDD
must never exceed 3.6V.
Note 3-3 The Package Power Dissipation specification assumes a recommended thermal via design consisting
of a 2x2 matrix of 0.3mm (12mil) vias at 1.0mm pitch connected to the ground plane with a 1.6 x
2.3mm thermal landing.
TABLE 3-1: ABSOLUTE MAXIMUM RATINGS
Voltage on 5V tolerant pins (V5VT_PIN) -0.3 to 5.5 V
Voltage on 5V tolerant pins (|V5VT_PIN - VDD|) Note 3-2 0 to 3.6 V
Voltage on VDD pin -0.3 to 4 V
Voltage on any other pin to GND -0.3 to VDD + 0.3 V
Package Power Dissipation up to TA = 85°C for 10 pin DFN
(see Note 3-3)
0.7 W
Junction to Ambient (θJA) 77.7 °C/W
Operating Ambient Temperature Range -40 to 125 °C
Storage Temperature Range -55 to 150 °C
ESD Rating, All Pins, HBM 8000 V
CAP1106
DS00001624B-page 8 2015 Microchip Technology Inc.
TABLE 3-2: ELECTRICAL SPECIFICATIONS
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
DC Power
Supply Voltage VDD 3.0 3.3 3.6 V
Supply Current
ISTBY 120 170 uA
Standby state active
1 sensor input monitored
Default conditions (8 avg, 70ms
cycle time)
ISTBY 50 uA
Standby state active
1 sensor input monitored
1 avg, 140ms cycle time,
IDSLEEP 5 15 uA
Deep Sleep state active
No communications
TA < 40°C
3.135 < VDD < 3.465V
IDD 500 600 uA Capacitive Sensing Active
Capacitive Touch Sensor Inputs
Maximum Base
Capacitance CBASE 50 pF Pad untouched
Minimum Detectable
Capacitive Shift ΔCTOUCH 20 fF
Pad touched - default conditions (1
avg, 35ms cycle time, 1x sensitivity)
Recommended Cap
Shift ΔCTOUCH 0.1 2 pF Pad touched - Not tested
Power Supply Rejection
PSR ±3 ±10 counts /
V
Untouched Current Counts
Base Capacitance 5pF - 50pF
Maximum sensitivity
Negative Delta Counts disabled
All other parameters default
Timing
Time to communications
ready tCOMM_DLY 15 ms
Time to first conversion
ready tCONV_DLY 170 200 ms
I/O Pins
Output Low Voltage VOL 0.4 V ISINK_IO = 8mA
Output High Voltage VOH VDD - 0.4 V ISOURCE_IO = 8mA
Input High Voltage VIH 2.0 V
Input Low Voltage VIL 0.8 V
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
SMBus Timing
Input Capacitance CIN 5 pF
Clock Frequency fSMB 10 400 kHz
Spike Suppression tSP 50 ns
Bus Free Time Stop to
Start tBUF 1.3 us
Start Setup Time tSU:STA 0.6 us
2015 Microchip Technology Inc. DS00001624B-page 9
CAP1106
Note 3-4 The ALERT pin will not glitch high or low at power up if connected to VDD or another voltage.
Note 3-5 The SMCLK and SMDATA pins will not glitch low at power up if connected to VDD or another voltage.
Start Hold Time tHD:STA 0.6 us
Stop Setup Time tSU:STO 0.6 us
Data Hold Time tHD:DAT 0 us When transmitting to the master
Data Hold Time tHD:DAT 0.3 us When receiving from the master
Data Setup Time tSU:DAT 0.6 us
Clock Low Period tLOW 1.3 us
Clock High Period tHIGH 0.6 us
Clock / Data Fall Time tFALL 300 ns Min = 20+0.1CLOAD ns
Clock / Data Rise
Time tRISE 300 ns Min = 20+0.1CLOAD ns
Capacitive Load CLOAD 400 pF per bus line
TABLE 3-2: ELECTRICAL SPECIFICATIONS (CONTINUED)
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
CAP1106
DS00001624B-page 10 2015 Microchip Technology Inc.
4.0 COMMUNICATIONS
4.1 Communications
The CAP1106 communicates using the SMBus or I2C protocol. If the proprietary BC-Link protocol is required for your
application, please contact your Microchip representative for ordering instructions. Regardless of the communications
mechanism, the device functionality remains unchanged.
4.1.1 SMBUS (I2C) COMMUNICATIONS
The supports the following protocols: Send Byte, Receive Byte, Read Byte, Write Byte, Read Block, and Write Block.
In addition, the device supports I2C formatting for block read and block write protocols.
See Section 4.2 and Section 4.3 for more information on the SMBus bus and protocols respectively.
APPLICATION NOTE: Upon power up, the CAP1106 will not respond to any communications for up to 15ms. After
this time, full functionality is available.
4.2 System Management Bus
The CAP1106 communicates with a host controller, such as an SIO, through the SMBus. The SMBus is a two-wire serial
communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in
Figure 4-1. Stretching of the SMCLK signal is supported; however, the CAP1106 will not stretch the clock signal.
4.2.1 SMBUS START BIT
The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the
SMBus Clock line is in a logic ‘1’ state.
4.2.2 SMBUS ADDRESS AND RD / WR BIT
The SMBus Address Byte consists of the 7-bit slave address followed by the RD / WR indicator bit. If this RD / WR bit
is a logic ‘0’, then the SMBus Host is writing data to the slave device. If this RD / WR bit is a logic ‘1’, then the SMBus
Host is reading data from the slave device.
The CAP1106 responds to SMBus address 0101_000(r/w).
4.2.3 SMBUS DATA BYTES
All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.
4.2.4 SMBUS ACK AND NACK BITS
The SMBus slave will acknowledge all data bytes that it receives. This is done by the slave device pulling the SMBus
Data line low after the 8th bit of each byte that is transmitted. This applies to both the Write Byte and Block Write protocols.
FIGURE 4-1: SMBus Timing Diagram
SMDATA
SMCLK
TLOW
TRISE
THIGH
TFALL
TBUF
THD:STA
P S S - Start Condition P - Stop Condition
THD:DAT TSU:DAT TSU:STA
THD:STA
P
TSU:STO
S
2015 Microchip Technology Inc. DS00001624B-page 11
CAP1106
The Host will NACK (not acknowledge) the last data byte to be received from the slave by holding the SMBus data line
high after the 8th data bit has been sent. For the Block Read protocol, the Host will ACK each data byte that it receives
except the last data byte.
4.2.5 SMBUS STOP BIT
The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the
SMBus clock line is in a logic ‘1’ state. When the CAP1106 detects an SMBus Stop bit and it has been communicating
with the SMBus protocol, it will reset its slave interface and prepare to receive further communications.
4.2.6 SMBUS TIMEOUT
The CAP1106 includes an SMBus timeout feature. Following a 30ms period of inactivity on the SMBus where the
SMCLK pin is held low, the device will timeout and reset the SMBus interface.
The timeout function defaults to disabled. It can be enabled by setting the TIMEOUT bit in the Configuration register
(see Section 6.6, "Configuration Registers").
4.2.7 SMBUS AND I2C COMPATIBILITY
The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus
2.0 and I2C specifications. For information on using the CAP1106 in an I2C system, refer to AN 14.0 Dedicated Slave
Devices in I2C Systems.
1. CAP1106 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz.
2. Minimum frequency for SMBus communications is 10kHz.
3. The SMBus slave protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality
is disabled by default in the CAP1106 and can be enabled by writing to the TIMEOUT bit. I2C does not have
a timeout.
4. The SMBus slave protocol will reset if both the clock and data lines are held at a logic ‘1’ for longer than 200µs
(idle condition). This function is disabled by default in the CAP1106 and can be enabled by writing to the TIMEOUT
bit. I2C does not have an idle condition.
5. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus).
6. I2C devices support block read and write differently. I2C protocol allows for unlimited number of bytes to be sent
in either direction. The SMBus protocol requires that an additional data byte indicating number of bytes to read /
write is transmitted. The CAP1106 supports I2C formatting only.
4.3 SMBus Protocols
The CAP1106 is SMBus 2.0 compatible and supports Write Byte, Read Byte, Send Byte, and Receive Byte as valid
protocols as shown below.
All of the below protocols use the convention in Table 4-1.
4.3.1 SMBUS WRITE BYTE
The Write Byte is used to write one byte of data to a specific register as shown in Table 4-2.
4.3.2 SMBUS READ BYTE
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4-3.
TABLE 4-1: PROTOCOL FORMAT
Data Sent to
Device
Data Sent to the
HOst
Data sent Data sent
TABLE 4-2: WRITE BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK Stop
1 ->0 0101_000 0 0 XXh 0 XXh 0 0 -> 1
CAP1106
DS00001624B-page 12 2015 Microchip Technology Inc.
4.3.3 SMBUS SEND BYTE
The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is
transferred during the Send Byte protocol as shown in Table 4-4.
APPLICATION NOTE: The Send Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.3.4 SMBUS RECEIVE BYTE
The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to
be at the right location (e.g., set via Send Byte). This is used for consecutive reads of the same register as shown in
Table 4-5.
APPLICATION NOTE: The Receive Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.4 I2C Protocols
The CAP1106 supports I2C Block Write and Block Read.
The protocols listed below use the convention in Table 4-1.
4.4.1 BLOCK WRITE
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in Table 4-6.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.4.2 BLOCK READ
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in Table 4-7.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
TABLE 4-3: READ BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data NACK Stop
1->0 0101_000 0 0 XXh 0 1 ->0 0101_000 1 0 XXh 1 0 -> 1
TABLE 4-4: SEND BYTE PROTOCOL
Start Slave Address WR ACK Register Address ACK Stop
1 -> 0 0101_000 0 0 XXh 0 0 -> 1
TABLE 4-5: RECEIVE BYTE PROTOCOL
Start Slave Address RD ACK Register Data NACK Stop
1 -> 0 0101_000 1 0 XXh 1 0 -> 1
TABLE 4-6: BLOCK WRITE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK
1 ->0 0101_000 0 0 XXh 0 XXh 0
Register Data ACK Register
Data
ACK . . . Register
Data
ACK Stop
XXh 0 XXh 0 . . . XXh 0 0 -> 1
2015 Microchip Technology Inc. DS00001624B-page 13
CAP1106
4.5 BC-Link Interface
The BC-Link is a proprietary bus developed to allow communication between a host controller device to a companion
device. This device uses this serial bus to read and write registers and for interrupt processing. The interface uses a
data port concept, where the base interface has an address register, data register and a control register, defined in the
8051’s SFR space.
Refer to documentation for the BC-Link compatible host controller for details on how to access the CAP1106-2 via the
BC-Link Interface.
TABLE 4-7: BLOCK READ PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data
1->0 0101_000 0 0 XXh 0 1 ->0 0101_000 1 0 XXh
ACK Register
Data
ACK Register
Data
ACK Register
Data
ACK . . . Register
Data
NACK Stop
0 XXh 0 XXh 0 XXh 0 . . . XXh 1 0 -> 1
CAP1106
DS00001624B-page 14 2015 Microchip Technology Inc.
5.0 GENERAL DESCRIPTION
The CAP1106 is a multiple channel Capacitive Touch sensor. The CAP1106 contains six (6) individual capacitive touch
sensor inputs. The device offers programmable sensitivity for use in touch sensor applications. Each sensor input automatically
recalibrates to compensate for gradual environmental changes.
The CAP1106 offers multiple power states. It operates at the lowest quiescent current during its Deep Sleep state. In
the low power Standby state, it can monitor one or more channels and respond to communications normally.
The device communicates with a host controller using or via SMBus / I2C. The host controller may poll the device for
updated information at any time or it may configure the device to flag an interrupt whenever a touch is detected on any
sensor pad.
A typical system diagram for the CAP1106 is shown in Figure 5-1.
FIGURE 5-1: System Diagram for CAP1106
CAP1106
CS6
SMDATA1 / BC_DATA2
SMCLK1 / BC_CLK2
VDD Embedded Controller ALERT#1 / BC_IRQ#2
CS4
CS2
CS5
CS3
CS1
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
1
= CAP1106-1
2
= CAP1106-2
2015 Microchip Technology Inc. DS00001624B-page 15
CAP1106
5.1 Power States
The CAP1106 has three operating states depending on the status of the STBY and DSLEEP bits. When the device transitions
between power states, previously detected touches (for inactive channels) are cleared and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active capacitive sensor inputs.
2. Standby - The device is in a lower power state. It will measure a programmable number of channels using the
Standby Configuration controls (see Section 6.20 through Section 6.22). Interrupts will still be generated based
on the active channels. The device will still respond to communications normally and can be returned to the Fully
Active state of operation by clearing the STBY bit.
3. Deep Sleep - The device is in its lowest power state. It is not monitoring any capacitive sensor inputs. While in
Deep Sleep, the device can be awakened by SMBus or SPI communications targeting the device. This will not
cause the DSLEEP to be cleared so the device will return to Deep Sleep once all communications have stopped.
5.2 Capacitive Touch Sensing
The CAP1106 contains six (6) independent capacitive touch sensor inputs. Each sensor input has dynamic range to
detect a change of capacitance due to a touch. Additionally, each sensor input can be configured to be automatically
and routinely re-calibrated.
5.2.1 SENSING CYCLE
Each capacitive touch sensor input has controls to be activated and included in the sensing cycle. When the device is
active, it automatically initiates a sensing cycle and repeats the cycle every time it finishes. The cycle polls through each
active sensor input starting with CS1 and extending through CS6. As each capacitive touch sensor input is polled, its
measurement is compared against a baseline “Not Touched” measurement. If the delta measurement is large enough,
a touch is detected and an interrupt is generated.
The sensing cycle time is programmable (see Section 6.10, "Averaging and Sampling Configuration Register").
5.2.2 RECALIBRATING SENSOR INPUTS
There are various options for recalibrating the capacitive touch sensor inputs. Recalibration re-sets the Base Count Registers
(Section 6.24, "Sensor Input Base Count Registers") which contain the “not touched” values used for touch detection
comparisons.
APPLICATION NOTE: The device will recalibrate all sensor inputs that were disabled when it transitions from
Standby. Likewise, the device will recalibrate all sensor inputs when waking out of Deep
Sleep.
5.2.2.1 Manual Recalibration
The Calibration Activate Registers (Section 6.11, "Calibration Activate Register") force recalibration of selected sensor
inputs. When a bit is set, the corresponding capacitive touch sensor input will be recalibrated (both analog and digital).
The bit is automatically cleared once the recalibration routine has finished.
5.2.2.2 Automatic Recalibration
Each sensor input is regularly recalibrated at a programmable rate (see Section 6.17, "Recalibration Configuration Register").
By default, the recalibration routine stores the average 64 previous measurements and periodically updates the
base “not touched” setting for the capacitive touch sensor input.
Note: During this recalibration routine, the sensor inputs will not detect a press for up to 200ms and the Sensor
Base Count Register values will be invalid. In addition, any press on the corresponding sensor pads will
invalidate the recalibration.
Note: Automatic recalibration only works when the delta count is below the active sensor input threshold. It is disabled
when a touch is detected.
CAP1106
DS00001624B-page 16 2015 Microchip Technology Inc.
5.2.2.3 Negative Delta Count Recalibration
It is possible that the device loses sensitivity to a touch. This may happen as a result of a noisy environment, an accidental
recalibration during a touch, or other environmental changes. When this occurs, the base untouched sensor input
may generate negative delta count values. The NEG_DELTA_CNT bits (see Section 6.17, "Recalibration Configuration
Register") can be set to force a recalibration after a specified number of consecutive negative delta readings.
5.2.2.4 Delayed Recalibration
It is possible that a “stuck button” occurs when something is placed on a button which causes a touch to be detected
for a long period. By setting the MAX_DUR_EN bit (see Section 6.6, "Configuration Registers"), a recalibration can be
forced when a touch is held on a button for longer than the duration specified in the MAX_DUR bits (see Section 6.8,
"Sensor Input Configuration Register").
5.2.3 PROXIMITY DETECTION
Each sensor input can be configured to detect changes in capacitance due to proximity of a touch. This circuitry detects
the change of capacitance that is generated as an object approaches, but does not physically touch, the enabled sensor
pad(s). When a sensor input is selected to perform proximity detection, it will be sampled from 1x to 128x per sampling
cycle. The larger the number of samples that are taken, the greater the range of proximity detection is available at the
cost of an increased overall sampling time.
5.2.4 MULTIPLE TOUCH PATTERN DETECTION
The multiple touch pattern (MTP) detection circuitry can be used to detect lid closure or other similar events. An event
can be flagged based on either a minimum number of sensor inputs or on specific sensor inputs simultaneously exceeding
an MTP threshold or having their Noise Flag Status Register bits set. An interrupt can also be generated. During an
MTP event, all touches are blocked (see Section 6.15, "Multiple Touch Pattern Configuration Register").
5.2.5 LOW FREQUENCY NOISE DETECTION
Each sensor input has an EMI noise detector that will sense if low frequency noise is injected onto the input with sufficient
power to corrupt the readings. If this occurs, the device will reject the corrupted sample and set the corresponding
bit in the Noise Status register to a logic ‘1’.
5.2.6 RF NOISE DETECTION
Each sensor input contains an integrated RF noise detector. This block will detect injected RF noise on the CS pin. The
detector threshold is dependent upon the noise frequency. If RF noise is detected on a CS line, that sample is removed
and not compared against the threshold.
5.3 ALERT# Pin
The ALERT# pin is an active low (or active high when configured) output that is driven when an interrupt event is
detected.
Whenever an interrupt is generated, the INT bit (see Section 6.1, "Main Control Register") is set. The ALERT# pin is
cleared when the INT bit is cleared by the user. Additionally, when the INT bit is cleared by the user, status bits are only
cleared if no touch is detected.
5.3.1 SENSOR INTERRUPT BEHAVIOR
The sensor interrupts are generated in one of two ways:
1. An interrupt is generated when a touch is detected and, as a user selectable option, when a release is detected
(by default - see Section 6.6). See Figure 5-3.
2. If the repeat rate is enabled then, so long as the touch is held, another interrupt will be generated based on the
programmed repeat rate (see Figure 5-2).
Note: During this recalibration, the device will not respond to touches.
Note: Delayed recalibration only works when the delta count is above the active sensor input threshold. If
enabled, it is invoked when a sensor pad touch is held longer than the MAX_DUR bit setting.
2015 Microchip Technology Inc. DS00001624B-page 17
CAP1106
When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch
is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button
is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a
touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it
is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed
repeat rate and upon release (if enabled).
APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon
sensor pad release and an active-low ALERT# pin.
APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.
FIGURE 5-2: Sensor Interrupt Behavior - Repeat Rate Enabled
FIGURE 5-3: Sensor Interrupt Behavior - No Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms)
Min Press Setting
(280ms)
Interrupt on
Touch
Button Repeat Rate
(175ms)
Button Repeat Rate
(175ms)
Interrupt on
Release
(optional)
ALERT# pin
(active low)
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms) Interrupt on
Touch Interrupt on
Release
(optional)
ALERT# pin
(active low)
CAP1106
DS00001624B-page 18 2015 Microchip Technology Inc.
6.0 REGISTER DESCRIPTION
The registers shown in Table 6-1 are accessible through the communications protocol. An entry of ‘-’ indicates that the
bit is not used and will always read ‘0’.
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER
Register
Address R/W Register Name Function Default Value Page
00h R/W Main Control Controls general power states and
power dissipation 00h Page 20
02h R General Status Stores general status bits 00h Page 21
03h R Sensor Input Status Returns the state of the sampled
capacitive touch sensor inputs 00h Page 21
0Ah R Noise Flag Status Stores the noise flags for sensor inputs 00h Page 22
10h R Sensor Input 1 Delta
Count Stores the delta count for CS1 00h Page 22
11h R Sensor Input 2 Delta
Count Stores the delta count for CS2 00h Page 22
12h R Sensor Input 3 Delta
Count Stores the delta count for CS3 00h Page 22
13h R Sensor Input 4 Delta
Count Stores the delta count for CS4 00h Page 22
14h R Sensor Input 5 Delta
Count Stores the delta count for CS5 00h Page 22
15h R Sensor Input 6 Delta
Count Stores the delta count for CS6 00h Page 22
1Fh R/W Sensitivity Control
Controls the sensitivity of the threshold
and delta counts and data scaling of
the base counts
2Fh Page 22
20h R/W Configuration Controls general functionality 20h Page 24
21h R/W Sensor Input Enable Controls whether the capacitive touch
sensor inputs are sampled 3Fh Page 25
22h R/W Sensor Input Configuration
Controls max duration and auto-repeat
delay for sensor inputs operating in the
full power state
A4h Page 25
23h R/W Sensor Input Configuration
2
Controls the MPRESS controls for all
sensor inputs 07h Page 26
24h R/W Averaging and Sampling
Config
Controls averaging and sampling window
39h Page 27
26h R/W Calibration Activate Forces re-calibration for capacitive
touch sensor inputs 00h Page 28
27h R/W Interrupt Enable Enables Interrupts associated with
capacitive touch sensor inputs 3Fh Page 29
28h R/W Repeat Rate Enable Enables repeat rate for all sensor
inputs 3Fh Page 29
2Ah R/W Multiple Touch Configuration
Determines the number of simultaneous
touches to flag a multiple touch
condition
80h Page 30
2Bh R/W Multiple Touch Pattern
Configuration
Determines the multiple touch pattern
(MTP) configuration 00h Page 30
2Dh R/W Multiple Touch Pattern
Determines the pattern or number of
sensor inputs used by the MTP circuitry
3Fh Page 31
2015 Microchip Technology Inc. DS00001624B-page 19
CAP1106
2Fh R/W Recalibration Configuration
Determines re-calibration timing and
sampling window 8Ah Page 32
30h R/W Sensor Input 1 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 1
40h Page 33
31h R/W Sensor Input 2 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 2
40h Page 33
32h R/W Sensor Input 3 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 3
40h Page 33
33h R/W Sensor Input 4 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 4
40h Page 33
34h R/W Sensor Input 5 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 5
40h Page 33
35h R/W Sensor Input 6 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 6
40h Page 33
38h R/W Sensor Input Noise
Threshold
Stores controls for selecting the noise
threshold for all sensor inputs 01h Page 33
Standby Configuration Registers
40h R/W Standby Channel Controls which sensor inputs are
enabled while in standby 00h Page 34
41h R/W Standby Configuration Controls averaging and cycle time
while in standby 39h Page 34
42h R/W Standby Sensitivity Controls sensitivity settings used while
in standby 02h Page 35
43h R/W Standby Threshold Stores the touch detection threshold
for active sensor inputs in standby 40h Page 36
44h R/W Configuration 2 Stores additional configuration controls
for the device 40h Page 24
Base Count Registers
50h R Sensor Input 1 Base
Count
Stores the reference count value for
sensor input 1 C8h Page 36
51h R Sensor Input 2 Base
Count
Stores the reference count value for
sensor input 2 C8h Page 36
52h R Sensor Input 3 Base
Count
Stores the reference count value for
sensor input 3 C8h Page 36
53h R Sensor Input 4 Base
Count
Stores the reference count value for
sensor input 4 C8h Page 36
54h R Sensor Input 5 Base
Count
Stores the reference count value for
sensor input 5 C8h Page 36
55h R Sensor Input 6 Base
Count
Stores the reference count value for
sensor input 6 C8h Page 36
B1h R Sensor Input 1 Calibration
Stores the upper 8-bit calibration value
for sensor input 1 00h Page 37
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1106
DS00001624B-page 20 2015 Microchip Technology Inc.
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first
applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics.
Any reads to undefined registers will return 00h. Writes to undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means that the user writes
a logic ‘0’ to it.
6.1 Main Control Register
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is increased, the
effective sensitivity is likewise increased as a smaller delta capacitance is required to generate the same delta count
values. The sensitivity settings may need to be adjusted along with the gain settings such that data overflow does not
occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
B2h R Sensor Input 2 Calibration
Stores the upper 8-bit calibration value
for sensor input 2 00h Page 37
B3h R Sensor Input 3 Calibration
Stores the upper 8-bit calibration value
for sensor input 3 00h Page 37
B4h R Sensor Input 4 Calibration
Stores the upper 8-bit calibration value
for sensor input 4 00h Page 37
B5h R Sensor Input 5 Calibration
Stores the upper 8-bit calibration value
for sensor input 5 00h Page 37
B6h R Sensor Input 6 Calibration
Stores the upper 8-bit calibration value
for sensor input 6 00h Page 37
B9h R Sensor Input Calibration
LSB 1
Stores the 2 LSBs of the calibration
value for sensor inputs 1 - 4 00h Page 37
BAh R Sensor Input Calibration
LSB 2
Stores the 2 LSBs of the calibration
value for sensor inputs 5- 6 00h Page 37
FDh R Product ID
CAP1106
Stores a fixed value that identifies
each product 55h Page 37
FEh R Manufacturer ID Stores a fixed value that identifies
Microchip 5Dh Page 38
FFh R Revision Stores a fixed value that represents
the revision number 83h Page 38
TABLE 6-2: MAIN CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
00h R/W Main Control GAIN[1:0] STBY DSLEEP - - - INT 00h
TABLE 6-3: GAIN BIT DECODE
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
0 0 1
01 2
10 4
11 8
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001624B-page 21
CAP1106
Bit 5 - STBY - Enables Standby.
• ‘0’ (default) - Sensor input scanning is active.
• ‘1’ - Capacitive touch sensor input scanning is limited to the sensor inputs set in the Standby Channel register (see
Section 6.20). The status registers will not be cleared until read. Sensor inputs that are no longer sampled will flag
a release and then remain in a non-touched state.
• Bit 4 - DSLEEP - Enables Deep Sleep by deactivating all functions. ‘0’ (default) - Sensor input scanning is active.
• ‘1’ - All sensor input scanning is disabled.. The status registers are automatically cleared and the INT bit is
cleared.
Bit 0 - INT - Indicates that there is an interrupt. When this bit is set, it asserts the ALERT# pin. If a channel detects a
touch and its associated interrupt enable bit is not set to a logic ‘1’, no action is taken.
This bit is cleared by writing a logic ‘0’ to it. When this bit is cleared, the ALERT# pin will be deasserted and all status
registers will be cleared if the condition has been removed.
• ‘0’ - No interrupt pending.
• ‘1’ - A touch has been detected on one or more channels and the interrupt has been asserted.
6.2 Status Registers
All status bits are cleared when the device enters the Deep Sleep (DSLEEP = ‘1’ - see Section 6.1).
6.2.1 GENERAL STATUS - 02H
Bit 2 - MULT - Indicates that the device is blocking detected touches due to the Multiple Touch detection circuitry (see
Section 6.14). This bit will not cause the INT bit to be set and hence will not cause an interrupt.
Bit 1 - MTP - Indicates that the device has detected a number of sensor inputs that exceed the MTP threshold either via
the pattern recognition or via the number of sensor inputs (see Section 6.15). This bit will cause the INT bit to be set if
the MTP_ALERT bit is also set. This bit will not be cleared until the condition that caused it to be set has been removed.
Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status register is set.
6.2.2 SENSOR INPUT STATUS - 03H
The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value of ‘0’ in any bit
indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a touch has been detected.
All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor input is no longer
present. If a touch is still detected, the bits will not be cleared (but this will not cause the interrupt to be asserted - see
Section 6.6).
Bit 5 - CS6 - Indicates that a touch was detected on Sensor Input 6.
Bit 4 - CS5 - Indicates that a touch was detected on Sensor Input 5.
Bit 3 - CS4 - Indicates that a touch was detected on Sensor Input 4.
Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3.
Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2.
Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1.
TABLE 6-4: STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
02h R General Status - - - - - MULT MTP TOUCH 00h
03h R Sensor Input Status
- - CS6 CS5 CS4 CS3 CS2 CS1 00h
CAP1106
DS00001624B-page 22 2015 Microchip Technology Inc.
6.3 Noise Flag Status Registers
The Noise Flag Status registers store status bits that are generated from the analog block if the detected noise is above
the operating region of the analog detector or the RF noise detector. These bits indicate that the most recently received
data from the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a particular
channel, the delta count value is reset to 00h and thus no touch is detected.
These bits are not sticky and will be cleared automatically if the analog block does not report a noise error.
APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP
threshold (see Section 5.2.4, "Multiple Touch Pattern Detection") even if the corresponding
delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not
counted twice.
APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a
sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,
if RF noise is detected on a sensor input, that sample will be discarded unless the
DIS_RF_NOISE bit is set.
6.4 Sensor Input Delta Count Registers
The Sensor Input Delta Count registers store the delta count that is compared against the threshold used to determine
if a touch has been detected. The count value represents a change in input due to the capacitance associated with a
touch on one of the sensor inputs and is referenced to a calibrated base “Not Touched” count value. The delta is an
instantaneous change and is updated once per sensor input per sensing cycle (see Section 5.2.1, "Sensing Cycle").
The value presented is a standard 2’s complement number. In addition, the value is capped at a value of 7Fh. A reading
of 7Fh indicates that the sensitivity settings are too high and should be adjusted accordingly (see Section 6.5).
The value is also capped at a negative value of 80h for negative delta counts which may result upon a release.
6.5 Sensitivity Control Register
TABLE 6-5: NOISE FLAG STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
0Ah R Noise Flag Status - - CS6_
NOISE
CS5_
NOISE
CS4_
NOISE
CS3_
NOISE
CS2_
NOISE
CS1_
NOISE 00h
TABLE 6-6: SENSOR INPUT DELTA COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
10h R Sensor Input 1
Delta Count Sign 64 32 16 8 4 2 1 00h
11h R Sensor Input 2
Delta Count Sign 64 32 16 8 4 2 1 00h
12h R Sensor Input 3
Delta Count Sign 64 32 16 8 4 2 1 00h
13h R Sensor Input 4
Delta Count Sign 64 32 16 8 4 2 1 00h
14h R Sensor Input 5
Delta Count Sign 64 32 16 8 4 2 1 00h
15h R Sensor Input 6
Delta Count Sign 64 32 16 8 4 2 1 00h
TABLE 6-7: SENSITIVITY CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
1Fh R/W Sensitivity Control - DELTA_SENSE[2:0] BASE_SHIFT[3:0] 2Fh
2015 Microchip Technology Inc. DS00001624B-page 23
CAP1106
The Sensitivity Control register controls the sensitivity of a touch detection.
Bits 6-4 DELTA_SENSE[2:0] - Controls the sensitivity of a touch detection. The sensitivity settings act to scale the relative
delta count value higher or lower based on the system parameters. A setting of 000b is the most sensitive while a
setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a smaller delta capacitance
corresponding to a “lighter” touch. These settings are more sensitive to noise, however, and a noisy environment may
flag more false touches with higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely, a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
Bits 3 - 0 - BASE_SHIFT[3:0] - Controls the scaling and data presentation of the Base Count registers. The higher the
value of these bits, the larger the range and the lower the resolution of the data presented. The scale factor represents
the multiplier to the bit-weighting presented in these register descriptions.
APPLICATION NOTE: The BASE_SHIFT[3:0] bits normally do not need to be updated. These settings will not affect
touch detection or sensitivity. These bits are sometimes helpful in analyzing the Cap Sensing
board performance and stability.
TABLE 6-8: DELTA_SENSE BIT DECODE
DELTA_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-9: BASE_SHIFT BIT DECODE
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
0 0 0 0 1x
0 0 0 1 2x
0 0 1 0 4x
0 0 1 1 8x
0 1 0 0 16x
0 1 0 1 32x
0 1 1 0 64x
0 1 1 1 128x
1 0 0 0 256x
All others 256x
(default = 1111b)
CAP1106
DS00001624B-page 24 2015 Microchip Technology Inc.
6.6 Configuration Registers
The Configuration registers control general global functionality that affects the entire device.
6.6.1 CONFIGURATION - 20H
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
• ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The SMBus interface
will not time out if the clock line is held low. Likewise, it will not reset if both the data and clock lines are held
high for longer than 200us. This is used for I2C compliance.
• ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The SMBus interface
will time out if the clock line is held low for longer than 30ms. Likewise, it will reset if both the data and clock
lines are held high for longer than 200us.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 6.19, "Sensor Input Noise Threshold
Register") is used by the device. Setting this bit disables the feature.
• ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does not exceed the
touch threshold, the sample is discarded and not used for the automatic re-calibration routine.
• ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold is used for the
automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the corresponding channel
is set to 0. Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
• ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held indefinitely and no
re-calibration will be performed on any sensor input.
• ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than the MAX_DUR
bit settings, then the re-calibration routine will be restarted (see Section 6.8).
6.6.2 CONFIGURATION 2 - 44H
Bit 6 - ALT_POL - Determines the ALERT# pin polarity and behavior.
• ‘0’ - The ALERT# pin is active high and push-pull.
• ‘1’ (default) - The ALERT# pin is active low and open drain.
Bit 5 - BLK_PWR_CTRL - Determines whether the device will reduce power consumption while waiting between conversion
time completion and the end of the polling cycle.
• ‘0’ (default) - The device will always power down as much as possible during the time between the end of the last
conversion and the end of the polling cycle.
• ‘1’ - The device will not power down the Cap Sensor during the time between the end of the last conversion and
the end of the polling cycle.
Bit 3 - SHOW_RF_NOISE - Determines whether the Noise Status bits will show RF Noise as the only input source.
• ‘0’ (default) - The Noise Status registers will show both RF noise and low frequency EMI noise if either is detected
on a capacitive touch sensor input.
• ‘1’ - The Noise Status registers will only show RF noise if it is detected on a capacitive touch sensor input. EMI
TABLE 6-10: CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
20h R/W Configuration TIMEOUT - DIS_ DIG_
NOISE
DIS_ ANA_
NOISE
MAX_
DUR_EN - --
A0h
(Rev B)
20h
(rev C)
44h R/W Configuration 2 - ALT_
POL
BLK_PWR_
CTRL
- SHOW_
RF_
NOISE
DIS_
RF_
NOISE
- INT_
REL_n 40h
2015 Microchip Technology Inc. DS00001624B-page 25
CAP1106
noise will still be detected and touches will be blocked normally; however, the status bits will not be updated.
Bit 2 - DIS_RF_NOISE - Determines whether the RF noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If RF noise is detected by the analog block, the delta count on the corresponding channel is set to 0.
Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if RF noise is detected.
Bit 0 - INT_REL_n - Controls the interrupt behavior when a release is detected on a button.
• ‘0’ (default) - An interrupt is generated when a press is detected and again when a release is detected and at the
repeat rate (if enabled - see Section 6.13).
• ‘1’ - An interrupt is generated when a press is detected and at the repeat rate but not when a release is detected.
6.7 Sensor Input Enable Registers
The Sensor Input Enable registers determine whether a capacitive touch sensor input is included in the sampling cycle.
The length of the sampling cycle is not affected by the number of sensor inputs measured.
Bit 5 - CS6_EN - Enables the CS6 input to be included during the sampling cycle.
• ‘0’ - The CS6 input is not included in the sampling cycle.
• ‘1’ (default) - The CS6 input is included in the sampling cycle.
Bit 4 - CS5_EN - Enables the CS5 input to be included during the sampling cycle.
Bit 3 - CS4_EN - Enables the CS4 input to be included during the sampling cycle.
Bit 2 - CS3_EN - Enables the CS3 input to be included during the sampling cycle.
Bit 1 - CS2_EN - Enables the CS2 input to be included during the sampling cycle.
Bit 0 - CS1_EN - Enables the CS1 input to be included during the sampling cycle.
6.8 Sensor Input Configuration Register
The Sensor Input Configuration Register controls timings associated with the Capacitive sensor inputs 1 - 6.
Bits 7 - 4 - MAX_DUR[3:0] - (default 1010b) - Determines the maximum time that a sensor pad is allowed to be touched
until the capacitive touch sensor input is recalibrated, as shown in Table 6-13.
TABLE 6-11: SENSOR INPUT ENABLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
21h R/W Sensor Input
Enable - - CS6_EN CS5_EN CS4_EN CS3_EN CS2_EN CS1_EN 3Fh
TABLE 6-12: SENSOR INPUT CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
22h R/W Sensor Input
Configuration MAX_DUR[3:0] RPT_RATE[3:0] A4h
TABLE 6-13: MAX_DUR BIT DECODE
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
0 0 0 0 560ms
0 0 0 1 840ms
0 0 1 0 1120ms
0 0 1 1 1400ms
0 1 0 0 1680ms
0 1 0 1 2240ms
0 1 1 0 2800ms
CAP1106
DS00001624B-page 26 2015 Microchip Technology Inc.
Bits 3 - 0 - RPT_RATE[3:0] - (default 0100b) Determines the time duration between interrupt assertions when auto
repeat is enabled. The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-14.
6.9 Sensor Input Configuration 2 Register
Bits 3 - 0 - M_PRESS[3:0] - (default 0111b) - Determines the minimum amount of time that sensor inputs configured to
use auto repeat must detect a sensor pad touch to detect a “press and hold” event. If the sensor input detects a touch
for longer than the M_PRESS[3:0] settings, a “press and hold” event is detected. If a sensor input detects a touch for
less than or equal to the M_PRESS[3:0] settings, a touch event is detected.
The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-16.
1 1 1 3360ms
1 0 0 0 3920ms
1 0 0 1 4480ms
1 0 1 0 5600ms (default)
1 0 1 1 6720ms
1 1 0 0 7840ms
1 1 0 1 8906ms
1 1 1 0 10080ms
1 1 1 1 11200ms
TABLE 6-14: RPT_RATE BIT DECODE
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms (default)
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-15: SENSOR INPUT CONFIGURATION 2 REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
23h R/W Sensor Input
Configuration 2 - - - - M_PRESS[3:0] 07h
TABLE 6-13: MAX_DUR BIT DECODE (CONTINUED)
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
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CAP1106
6.10 Averaging and Sampling Configuration Register
The Averaging and Sampling Configuration register controls the number of samples taken and the total sensor input
cycle time for all active sensor inputs while the device is functioning in Active state.
Bits 6 - 4 - AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor cycle
as shown in Table 6-18. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
For example, if CS1, CS2, and CS3 are sampled during the sensor cycle, and the AVG[2:0] bits are set to take 4 samples
per channel, then the full sensor cycle will be: CS1, CS1, CS1, CS1, CS2, CS2, CS2, CS2, CS3, CS3, CS3, CS3.
Bits 3 - 2 - SAMP_TIME[1:0] - Determines the time to take a single sample as shown in Table 6-19.
TABLE 6-16: M_PRESS BIT DECODE
M_PRESS[3:0]
M_PRESS SETTINGS
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms (default)
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-17: AVERAGING AND SAMPLING CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
24h R/W Averaging and
Sampling Config AVG[2:0] SAMP_TIME[1:0] CYCLE_TIME
[1:0] 39h
TABLE 6-18: AVG BIT DECODE
AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
CAP1106
DS00001624B-page 28 2015 Microchip Technology Inc.
Bits 1 - 0 - CYCLE_TIME[1:0] - Determines the overall cycle time for all measured channels during normal operation as
shown in Table 6-20. All measured channels are sampled at the beginning of the cycle time. If additional time is remaining,
then the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The AVG[2:0] bits will take priority so that if more samples
are required than would normally be allowed during the cycle time, the cycle time will be
extended as necessary to accommodate the number of samples to be measured.
6.11 Calibration Activate Register
The Calibration Activate register forces the respective sensor inputs to be re-calibrated affecting both the analog and
digital blocks. During the re-calibration routine, the sensor inputs will not detect a press for up to 600ms and the Sensor
Input Base Count register values will be invalid. During this time, any press on the corresponding sensor pads will invalidate
the re-calibration. When finished, the CALX[9:0] bits will be updated (see Section 6.25).
When the corresponding bit is set, the device will perform the calibration and the bit will be automatically cleared once
the re-calibration routine has finished.
Bit 5 - CS6_CAL - When set, the CS6 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 4 - CS5_CAL - When set, the CS5 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 3 - CS4_CAL - When set, the CS4 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 2 - CS3_CAL - When set, the CS3 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 1 - CS2_CAL - When set, the CS2 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 0 - CS1_CAL - When set, the CS1 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
TABLE 6-19: SAMP_TIME BIT DECODE
SAMP_TIME[1:0]
Sample Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-20: CYCLE_TIME BIT DECODE
CYCLE_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-21: CALIBRATION ACTIVATE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
26h R/W Calibration
Activate - - CS6_
CAL
CS5_
CAL
CS4_
CAL
CS3_
CAL
CS2_
CAL
CS1_
CAL 00h
2015 Microchip Technology Inc. DS00001624B-page 29
CAP1106
6.12 Interrupt Enable Register
The Interrupt Enable register determines whether a sensor pad touch or release (if enabled) causes the interrupt pin to
be asserted.
Bit 5 - CS6_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS6 (associated with the CS6
status bit).
• ‘0’ - The interrupt pin will not be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
• ‘1’ (default) - The interrupt pin will be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
Bit 4 - CS5_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS5 (associated with the CS5
status bit).
Bit 3 - CS4_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS4 (associated with the CS4
status bit).
Bit 2 - CS3_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS3 (associated with the CS3
status bit).
Bit 1 - CS2_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS2 (associated with the CS2
status bit).
Bit 0 - CS1_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS1 (associated with the CS1
status bit).
6.13 Repeat Rate Enable Register
The Repeat Rate Enable register enables the repeat rate of the sensor inputs as described in Section 5.3.1.
Bit 5 - CS6_RPT_EN - Enables the repeat rate for capacitive touch sensor input 6.
• ‘0’ - The repeat rate for CS6 is disabled. It will only generate an interrupt when a touch is detected and when a
release is detected no matter how long the touch is held for.
• ‘1’ (default) - The repeat rate for CS6 is enabled. In the case of a “touch” event, it will generate an interrupt when a
touch is detected and a release is detected (as determined by the INT_REL_n bit - see Section 6.6). In the case of
a “press and hold” event, it will generate an interrupt when a touch is detected and at the repeat rate so long as
the touch is held.
Bit 4 - CS5_RPT_EN - Enables the repeat rate for capacitive touch sensor input 5.
Bit 3 - CS4_RPT_EN - Enables the repeat rate for capacitive touch sensor input 4.
Bit 2 - CS3_RPT_EN - Enables the repeat rate for capacitive touch sensor input 3.
Bit 1 - CS2_RPT_EN - Enables the repeat rate for capacitive touch sensor input 2.
Bit 0 - CS1_RPT_EN - Enables the repeat rate for capacitive touch sensor input 1.
TABLE 6-22: INTERRUPT ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
27h R/W Interrupt
Enable - - CS6_
INT_EN
CS5_
INT_EN
CS4_
INT_EN
CS3_
INT_EN
CS2_
INT_EN
CS1_
INT_EN 3Fh
TABLE 6-23: REPEAT RATE ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
28h R/W Repeat Rate
Enable - - CS6_
RPT_EN
CS5_
RPT_EN
CS4_
RPT_EN
CS3_
RPT_EN
CS2_
RPT_EN
CS1_
RPT_EN 3Fh
CAP1106
DS00001624B-page 30 2015 Microchip Technology Inc.
6.14 Multiple Touch Configuration Register
The Multiple Touch Configuration register controls the settings for the multiple touch detection circuitry. These settings
determine the number of simultaneous buttons that may be pressed before additional buttons are blocked and the MULT
status bit is set.
Bit 7 - MULT_BLK_EN - Enables the multiple button blocking circuitry.
• ‘0’ - The multiple touch circuitry is disabled. The device will not block multiple touches.
• ‘1’ (default) - The multiple touch circuitry is enabled. The device will flag the number of touches equal to programmed
multiple touch threshold and block all others. It will remember which sensor inputs are valid and block all
others until that sensor pad has been released. Once a sensor pad has been released, the N detected touches
(determined via the cycle order of CS1 - CS6) will be flagged and all others blocked.
Bits 3 - 2 - B_MULT_T[1:0] - Determines the number of simultaneous touches on all sensor pads before a Multiple Touch
Event is detected and sensor inputs are blocked. The bit decode is given by Table 6-25.
6.15 Multiple Touch Pattern Configuration Register
The Multiple Touch Pattern Configuration register controls the settings for the multiple touch pattern detection circuitry.
This circuitry works like the multiple touch detection circuitry with the following differences:
1. The detection threshold is a percentage of the touch detection threshold as defined by the MTP_TH[1:0] bits
whereas the multiple touch circuitry uses the touch detection threshold.
2. The MTP detection circuitry either will detect a specific pattern of sensor inputs as determined by the Multiple
Touch Pattern register settings or it will use the Multiple Touch Pattern register settings to determine a minimum
number of sensor inputs that will cause the MTP circuitry to flag an event. When using pattern recognition mode,
if all of the sensor inputs set by the Multiple Touch Pattern register have a delta count greater than the MTP
threshold or have their corresponding Noise Flag Status bits set, the MTP bit will be set. When using the absolute
number mode, if the number of sensor inputs with thresholds above the MTP threshold or with Noise Flag Status
bits set is equal to or greater than this number, the MTP bit will be set.
3. When an MTP event occurs, all touches are blocked and an interrupt is generated.
4. All sensor inputs will remain blocked so long as the requisite number of sensor inputs are above the MTP threshold
or have Noise Flag Status bits set. Once this condition is removed, touch detection will be restored. Note that
the MTP status bit is only cleared by writing a ‘0’ to the INT bit once the condition has been removed.
TABLE 6-24: MULTIPLE TOUCH CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Ah R/W Multiple Touch
Config
MULT_
BLK_
EN
- - - B_MULT_T[1:0] - - 80h
TABLE 6-25: B_MULT_T BIT DECODE
B_MULT_T[1:0]
Number of Simultaneous Touches
1 0
0 0 1 (default)
01 2
10 3
11 4
TABLE 6-26: MULTIPLE TOUCH PATTERN CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Bh R/W Multiple Touch
Pattern Config MTP_ EN - - MTP_TH[1:0] COMP_
PTRN
MTP_
ALERT 00h
2015 Microchip Technology Inc. DS00001624B-page 31
CAP1106
Bit 7 - MTP_EN - Enables the multiple touch pattern detection circuitry.
• ‘0’ (default) - The MTP detection circuitry is disabled.
• ‘1’ - The MTP detection circuitry is enabled.
Bits 3-2 - MTP_TH[1:0] - Determine the MTP threshold, as shown in Table 6-27. This threshold is a percentage of sensor
input threshold (see Section 6.18, "Sensor Input Threshold Registers") when the device is in the Fully Active state or of
the standby threshold (see Section 6.23, "Standby Threshold Register") when the device is in the Standby state.
Bit 1 - COMP_PTRN - Determines whether the MTP detection circuitry will use the Multiple Touch Pattern register as a
specific pattern of sensor inputs or as an absolute number of sensor inputs.
• ‘0’ (default) - The MTP detection circuitry will use the Multiple Touch Pattern register bit settings as an absolute
minimum number of sensor inputs that must be above the threshold or have Noise Flag Status bits set. The number
will be equal to the number of bits set in the register.
• ‘1’ - The MTP detection circuitry will use pattern recognition. Each bit set in the Multiple Touch Pattern register
indicates a specific sensor input that must have a delta count greater than the MTP threshold or have a Noise Flag
Status bit set. If the criteria are met, the MTP status bit will be set.
Bit 0 - MTP_ALERT - Enables an interrupt if an MTP event occurs. In either condition, the MTP status bit will be set.
• ‘0’ (default) - If an MTP event occurs, the ALERT# pin is not asserted.
• ‘1’ - If an MTP event occurs, the ALERT# pin will be asserted.
6.16 Multiple Touch Pattern Register
The Multiple Touch Pattern register acts as a pattern to identify an expected sensor input profile for diagnostics or other
significant events. There are two methods for how the Multiple Touch Pattern register is used: as specific sensor inputs
or number of sensor input that must exceed the MTP threshold or have Noise Flag Status bits set. Which method is used
is based on the COMP_PTRN bit (see Section 6.15). The methods are described below.
1. Specific Sensor Inputs: If, during a single polling cycle, the specific sensor inputs above the MTP threshold or
with Noise Flag Status bits set match those bits set in the Multiple Touch Pattern register, an MTP event is
flagged.
2. Number of Sensor Inputs: If, during a single polling cycle, the number of sensor inputs with a delta count above
the MTP threshold or with Noise Flag Status bits set is equal to or greater than the number of pattern bits set, an
MTP event is flagged.
Bit 5 - CS6_PTRN - Determines whether CS6 is considered as part of the Multiple Touch Pattern.
• ‘0’ - CS6 is not considered a part of the pattern.
• ‘1’ - CS6 is considered a part of the pattern or the absolute number of sensor inputs that must have a delta count
greater than the MTP threshold or have the Noise Flag Status bit set is increased by 1.
Bit 4 - CS5_PTRN - Determines whether CS5 is considered as part of the Multiple Touch Pattern.
Bit 3 - CS4_PTRN - Determines whether CS4 is considered as part of the Multiple Touch Pattern.
Bit 2 - CS3_PTRN - Determines whether CS3 is considered as part of the Multiple Touch Pattern.
TABLE 6-27: MTP_TH BIT DECODE
MTP_TH[1:0]
Threshold Divide Setting
1 0
0 0 12.5% (default)
0 1 25%
1 0 37.5%
1 1 100%
TABLE 6-28: MULTIPLE TOUCH PATTERN REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Dh R/W Multiple
Touch Pattern - - CS6_
PTRN
CS5_
PTRN
CS4_
PTRN
CS3_
PTRN
CS2_
PTRN
CS1_
PTRN 3Fh
CAP1106
DS00001624B-page 32 2015 Microchip Technology Inc.
Bit 1 - CS2_PTRN - Determines whether CS2 is considered as part of the Multiple Touch Pattern.
Bit 0 - CS1_PTRN - Determines whether CS1 is considered as part of the Multiple Touch Pattern.
6.17 Recalibration Configuration Register
The Recalibration Configuration register controls the automatic re-calibration routine settings as well as advanced controls
to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor Input 1 Threshold
register.
• ‘0’ - Each Sensor Input X Threshold register is updated individually.
• ‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor Input Threshold
registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input Threshold 6). The individual Sensor
Input X Threshold registers (Sensor Input 2 Threshold through Sensor Input 6 Threshold) can be individually
updated at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise status bit is set.
• ‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
• ‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if the noise status bit
is set.
• ‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
• ‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to trigger a digital recalibration
as shown in Table 6-30.
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-calibration routine.
The settings apply to all sensor inputs universally (though individual sensor inputs can be configured to support re-calibration
- see Section 6.11).
TABLE 6-29: RECALIBRATION CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Fh R/W Recalibration
Configuration
BUT_
LD_TH
NO_
CLR_
INTD
NO_
CLR_
NEG
NEG_DELTA_
CNT[1:0] CAL_CFG[2:0] 8Ah
TABLE 6-30: NEG_DELTA_CNT BIT DECODE
NEG_DELTA_CNT[1:0]
Number of Consecutive Negative Delta Count Values
1 0
00 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
TABLE 6-31: CAL_CFG BIT DECODE
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
0 0 0 16 16
0 0 1 32 32
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CAP1106
Note 6-1 Recalibration Samples refers to the number of samples that are measured and averaged before the
Base Count is updated however does not control the base count update period.
Note 6-2 Update Time refers to the amount of time (in polling cycle periods) that elapses before the Base
Count is updated. The time will depend upon the number of channels active, the averaging setting,
and the programmed cycle time.
6.18 Sensor Input Threshold Registers
The Sensor Input Threshold registers store the delta threshold that is used to determine if a touch has been detected.
When a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with
a touch. If the sensor input change exceeds the threshold settings, a touch is detected.
When the BUT_LD_TH bit is set (see Section 6.17 - bit 7), writing data to the Sensor Input 1 Threshold register will
update all of the sensor input threshold registers (31h - 35h inclusive).
6.19 Sensor Input Noise Threshold Register
The Sensor Input Noise Threshold register controls the value of a secondary internal threshold to detect noise and
improve the automatic recalibration routine. If a capacitive touch sensor input exceeds the Sensor Input Noise Threshold
but does not exceed the sensor input threshold, it is determined to be caused by a noise spike. That sample is not used
by the automatic re-calibration routine. This feature can be disabled by setting the DIS_DIG_NOISE bit.
0 1 0 64 64 (default)
0 1 1 128 128
1 0 0 256 256
1 0 1 256 1024
1 1 0 256 2048
1 1 1 256 4096
TABLE 6-32: SENSOR INPUT THRESHOLD REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
30h R/W Sensor Input 1
Threshold - 64 32 16 8 4 2 1 40h
31h R/W Sensor Input 2
Threshold - 64 32 16 8 4 2 1 40h
32h R/W Sensor Input 3
Threshold - 64 32 16 8 4 2 1 40h
33h R/W Sensor Input 4
Threshold - 64 32 16 8 4 2 1 40h
34h R/W Sensor Input 5
Threshold - 64 32 16 8 4 2 1 40h
35h R/W Sensor Input 6
Threshold - 64 32 16 8 4 2 1 40h
TABLE 6-33: SENSOR INPUT NOISE THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
38h R/W Sensor Input
Noise Threshold CS_BN_TH [1:0] 01h
TABLE 6-31: CAL_CFG BIT DECODE (CONTINUED)
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
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DS00001624B-page 34 2015 Microchip Technology Inc.
Bits 1-0 - CS1_BN_TH[1:0] - Controls the noise threshold for all capacitive touch sensor inputs, as shown in Table 6-34.
The threshold is proportional to the threshold setting.
6.20 Standby Channel Register
The Standby Channel register controls which (if any) capacitive touch sensor inputs are active during Standby.
Bit 5 - CS6_STBY - Controls whether the CS6 channel is active in Standby.
• ‘0’ (default) - The CS6 channel not be sampled during Standby mode.
• ‘1’ - The CS6 channel will be sampled during Standby Mode. It will use the Standby threshold setting, and the
standby averaging and sensitivity settings.
Bit 4 - CS5_STBY - Controls whether the CS5 channel is active in Standby.
Bit 3 - CS4_STBY - Controls whether the CS4 channel is active in Standby.
Bit 2 - CS3_STBY - Controls whether the CS3 channel is active in Standby.
Bit 1 - CS2_STBY - Controls whether the CS2 channel is active in Standby.
Bit 0 - CS1_STBY - Controls whether the CS1 channel is active in Standby.
6.21 Standby Configuration Register
The Standby Configuration register controls averaging and cycle time for those sensor inputs that are active in Standby.
This register is useful for detecting proximity on a small number of sensor inputs as it allows the user to change averaging
and sample times on a limited number of sensor inputs and still maintain normal functionality in the fully active
state.
Bit 7 - AVG_SUM - Determines whether the active sensor inputs will average the programmed number of samples or
whether they will accumulate for the programmed number of samples.
• ‘0’ - (default) - The active sensor input delta count values will be based on the average of the programmed number
of samples when compared against the threshold.
• ‘1’ - The active sensor input delta count values will be based on the summation of the programmed number of
samples when compared against the threshold. This bit should only be set when performing proximity detection as
a physical touch will overflow the delta count registers and may result in false readings.
Bits 6 - 4 - STBY_AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor
cycle as shown in Table 6-37. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
TABLE 6-34: CSX_BN_TH BIT DECODE
CS_BN_TH[1:0]
Percent Threshold Setting
1 0
0 0 25%
0 1 37.5% (default)
1 0 50%
1 1 62.5%
TABLE 6-35: STANDBY CHANNEL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
40h R/W Standby Channel - - CS6_
STBY
CS5_
STBY
CS4_
STBY
CS3_
STBY
CS2_
STBY
CS1_
STBY 00h
TABLE 6-36: STANDBY CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
41h R/W Standby Configuration
AVG_
SUM STBY_AVG[2:0] STBY_SAMP_
TIME[1:0]
STBY_CY_TIME
[1:0] 39h
2015 Microchip Technology Inc. DS00001624B-page 35
CAP1106
Bit 3-2 - STBY SAMP_TIME[1:0] - Determines the time to take a single sample when the device is in Standby as shown
in Table 6-38.
Bits 1 - 0 - STBY_CY_TIME[2:0] - Determines the overall cycle time for all measured channels during standby operation
as shown in Table 6-39. All measured channels are sampled at the beginning of the cycle time. If additional time is
remaining, the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The STBY_AVG[2:0] bits will take priority so that if more
samples are required than would normally be allowed during the cycle time, the cycle time
will be extended as necessary to accommodate the number of samples to be measured.
6.22 Standby Sensitivity Register
The Standby Sensitivity register controls the sensitivity for sensor inputs that are active in Standby.
TABLE 6-37: STBY_AVG BIT DECODE
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-38: STBY_SAMP_TIME BIT DECODE
STBY_SAMP_TIME[1:0]
Sampling Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-39: STBY_CY_TIME BIT DECODE
STBY_CY_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-40: STANDBY SENSITIVITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
42h R/W Standby Sensitivity
- - - - - STBY_SENSE[2:0] 02h
CAP1106
DS00001624B-page 36 2015 Microchip Technology Inc.
Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensor inputs that are active in Standby. The sensitivity settings
act to scale the relative delta count value higher or lower based on the system parameters. A setting of 000b is the
most sensitive while a setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a
smaller delta C corresponding to a “lighter” touch. These settings are more sensitive to noise however and a noisy environment
may flag more false touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
6.23 Standby Threshold Register
The Standby Threshold register stores the delta threshold that is used to determine if a touch has been detected. When
a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with a
touch. If the sensor input change exceeds the threshold settings, a touch is detected.
6.24 Sensor Input Base Count Registers
TABLE 6-41: STBY_SENSE BIT DECODE
STBY_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-42: STANDBY THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
43h R/W Standby Threshold
- 64 32 16 8 4 2 1 40h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
50h R Sensor Input 1
Base Count 128 64 32 16 8 4 2 1 C8h
51h R Sensor Input 2
Base Count 128 64 32 16 8 4 2 1 C8h
52h R Sensor Input 3
Base Count 128 64 32 16 8 4 2 1 C8h
53h R Sensor Input 4
Base Count 128 64 32 16 8 4 2 1 C8h
54h R Sensor Input 5
Base Count 128 64 32 16 8 4 2 1 C8h
55h R Sensor Input 6
Base Count 128 64 32 16 8 4 2 1 C8h
2015 Microchip Technology Inc. DS00001624B-page 37
CAP1106
The Sensor Input Base Count registers store the calibrated “Not Touched” input value from the capacitive touch sensor
inputs. These registers are periodically updated by the re-calibration routine.
The routine uses an internal adder to add the current count value for each reading to the sum of the previous readings
until sample size has been reached. At this point, the upper 16 bits are taken and used as the Sensor Input Base Count.
The internal adder is then reset and the re-calibration routine continues.
The data presented is determined by the BASE_SHIFT[3:0] bits (see Section 6.5).
6.25 Sensor Input Calibration Registers
The Sensor Input Calibration registers hold the 10-bit value that represents the last calibration value.
6.26 Product ID Register
The Product ID register stores a unique 8-bit value that identifies the device.
6.27 Manufacturer ID Register
The Vendor ID register stores an 8-bit value that represents Microchip.
TABLE 6-44: SENSOR INPUT CALIBRATION REGISTERS
ADDR Register R/W B7 B6 B5 B4 B3 B2 B1 B0 Default
B1h Sensor Input 1
Calibration R CAL1_9 CAL1_8 CAL1_7 CAL1_6 CAL1_5 CAL1_4 CAL1_3 CAL1_2 00h
B2h Sensor Input 2
Calibration R CAL2_9 CAL2_8 CAL2_7 CAL2_6 CAL2_5 CAL2_4 CAL2_3 CAL2_2 00h
B3h Sensor Input 3
Calibration R CAL3_9 CAL3_8 CAL3_7 CAL3_6 CAL3_5 CAL3_4 CAL3_3 CAL3_2 00h
B4h Sensor Input 4
Calibration R CAL4_9 CAL4_8 CAL4_7 CAL4_6 CAL4_5 CAL4_4 CAL4_3 CAL4_2 00h
B5h Sensor Input 5
Calibration R CAL5_9 CAL5_8 CAL5_7 CAL5_6 CAL5_5 CAL5_4 CAL5_3 CAL5_2 00h
B6h Sensor Input 6
Calibration R CAL6_9 CAL6_8 CAL6_7 CAL6_6 CAL6_5 CAL6_4 CAL6_3 CAL6_2 00h
B9h
Sensor Input
Calibration LSB
1
R CAL4_1 CAL4_0 CAL3_1 CAL3_0 CAL2_1 CAL2_0 CAL1_1 CAL1_0 00h
BAh
Sensor Input
Calibration LSB
2
R - - - - CAL6_1 CAL6_0 CAL5_1 CAL5_0 00h
TABLE 6-45: PRODUCT ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FDh R Product ID
CAP1106
0 1 0 1 0 1 0 1 55h
TABLE 6-46: VENDOR ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FEh R Manufacturer ID 0 1 0 1 1 1 0 1 5Dh
CAP1106
DS00001624B-page 38 2015 Microchip Technology Inc.
6.28 Revision Register
The Revision register stores an 8-bit value that represents the part revision.
TABLE 6-47: REVISION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FFh R Revision 1 0 0 0 0 0 1 1 83h
2015 Microchip Technology Inc. DS00001624B-page 39
CAP1106
7.0 PACKAGE INFORMATION
7.1 CAP1106 Package Drawings
FIGURE 7-1: 10-Pin DFN 3mm x 3mm Package Drawings (1 of 2)
Note: For the most current package drawings,
see the Microchip Packaging Specification at
http://www.microchip.com/packaging
CAP1106
DS00001624B-page 40 2015 Microchip Technology Inc.
FIGURE 7-2: 10-Pin DFN 3mm x 3mm Package Drawings (2 of 2)
Note: For the most current package drawings,
see the Microchip Packaging Specification at
http://www.microchip.com/packaging
2015 Microchip Technology Inc. DS00001624B-page 41
CAP1106
7.2 Package Marking
FIGURE 7-3: CAP1106 Package Markings
1 8 W
NNNA
e4
TOP
BOTTOM
Bottom marking not allowed
PB-FREE/GREEN SYMBOL
PIN 1 (Ni/Pd PP-LF)
Line 1 – Device Code, Week 2x 0.6
Line 2 – Alphanumeric Traceability Code
W
Lines 1-2:
Line 3:
Center Horizontal Alignment
As Shown
CAP1106
DS00001624B-page 42 2015 Microchip Technology Inc.
APPENDIX A: DEVICE DELTA
A.1 Delta from CAP1006 to CAP1106
1. Updated circuitry to improve power supply rejection.
2. Added Multiple Touch Pattern detection circuitry. See Section 6.15, "Multiple Touch Pattern Configuration Register".
3. Added General Status register to flag Multiple touches, Multiple Touch Pattern issues and general touch detections.
See Section 6.2, "Status Registers".
4. Added bits 6 and 5 to the Recalibration Configuration register (2Fh - see Section 6.17, "Recalibration Configuration
Register"). These bits control whether the accumulation of intermediate data and the consecutive negative
delta counts counter are cleared when the noise status bit is set.
5. Added Configuration 2 register for noise detection controls and control to interrupt on press but not on release.
Added control to change alert pin polarity. See Section 6.6, "Configuration Registers".
6. Updated Deep Sleep behavior so that device does not clear DSLEEP bit on received communications but will
wake to communicate.
7. Register delta:
Table A.1 Register Delta From CAP1006 to CAP1106
Address Register Delta Delta Default
00h
Page 20
Changed - Main Status /
Control
added bits 7-6 to control gain 00h
02h
Page 21
New - General Status new register to store MTP, MULT, and general
TOUCH bits
00h
44h
Page 24
New - Configuration 2 new register to control alert polarity, and
noise detection, and interrupt on release
00h
24h
Page 27
Changed - Averaging
Control
updated register bits - moved
SAMP_AVG[2:0] bits and added SAMP_-
TIME bit 1. Default changed
39h
2Bh
Page 30
New - Multiple Touch
Pattern Configuration
new register for Multiple Touch Pattern
configuration - enable and threshold settings
80h
2Dh
Page 31
New - Multiple Touch
Pattern Register
new register for Multiple Touch Pattern
detection circuitry - pattern or number of
sensor inputs
3Fh
2Fh
Page 32
Changed - Recalibration
Configuration
updated register - updated CAL_CFG bit
decode to add a 128 averages setting and
removed highest time setting. Default
changed. Added bit 6 NO_CLR_INTD and
bit 5 NO_CLR_NEG.
8Ah
38h
Page 33
Changed - Sensor Input
Noise Threshold
updated register bits - removed bits 7 - 3
and consolidated all controls into bits 1 - 0.
These bits will set the noise threshold for
all channels. Default changed
01h
39h Removed - Noise
Threshold Register 2
removed register n/a
41h
Page 34
Changed - Standby Configuration
updated register bits - moved
STBY_AVG[2:0] bits and added STBY_-
TIME bit 1. Default changed
39h
FDh
Page 37
Changed - Product ID Changed bit decode for CAP1106 55h
2015 Microchip Technology Inc. DS00001624B-page 43
CAP1106
APPENDIX B: DATA SHEET REVISION HISTORY
Revision Section/Figure/Entry Correction
DS00001624B (02-09-15)
Features, Table 2-2, Table 2-
2, "Pin Types", Section 5.0,
"General Description"
References to BC-Link Interface, BC_DATA, BC_-
CLK, BC-IRQ#, BC-Link bus have been removed
Application Note under Table
2-6
[BC-Link] hidden in data sheet
Table 3-2, "Electrical Specifications"
BC-Link Timing Section hidden in data sheet
Table 4-1 Protocol Used for 68K Pull Down Resistor changed
from “BC-Link Communications” to “Reserved”
Section 4.1.3 BC-Link Communications
Removed this section and Application Note
Section 4.2.2, "SMBus
Address and RD / WR Bit"
Replaced “client address” with “slave address” in this
section.
Section 4.2.4, SMBus ACK
and NACK Bits, Section 4.2.5,
SMBus Stop Bit,Section 4.2.7,
SMBus and I2C Compatibility
Replaced “client” with “slave” in these sections.
Table 4-3, "Read Byte Protocol"
Heading changed from “Client Address” to “Slave
Address”
Section 5.1, Power States Removed “BC-Link” Application Notes
Table 6-1 Register Name for Register Address 77h changed
from “LED Linked Transition Control” to “Linked LED
Transition Control”
Section 6.1 Main Control Register
BC-Link paragraph removed from Bit 4 under Table
6-3
Section 7.7 Package Marking Updated package drawing
Figure 7-25 CAP1106 with
BC-Link Support Package
Markings
Removed figure.
Appendix A: Device Delta changed 2Dh to 2Fh in item #12
Product Identification System Removed BC-Link references
REV A REV A replaces previous SMSC version Rev. 1.32 (01-05-12)
Rev. 1.32 (01-05-12) Table 3-2, "Electrical Specifications"
Added conditions for tHD:DAT.
Section 4.2.7, "SMBus and
I2C Compatibility"
Renamed from “SMBus and I2C Compliance.”
First paragraph, added last sentence: “For information
on using the CAP1106 in an I2C system, refer to
SMSC AN 14.0 SMSC Dedicated Slave Devices in
I
2C Systems.”
Added: CAP1106 supports I2C fast mode at 400kHz.
This covers the SMBus max time of 100kHz.
Section 6.4, "Sensor Input
Delta Count Registers"
Changed negative value cap from FFh to 80h.
Rev. 1.31 (08-18-11) Section 4.3.3, "SMBus Send
Byte"
Added an application note: The Send Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit is
set).
Section 4.3.4, "SMBus
Receive Byte"
Added an application note: The Receive Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit
is set).
CAP1106
DS00001624B-page 44 2015 Microchip Technology Inc.
Section 6.2, "Status Registers"
Removed RESET as bit 3 in register 02h.
Rev. 1.3 (05-18-11) Section 6.28, "Revision Register"
Updated revision ID from 82h to 83h.
Section 6.2, "Status Registers"
Added RESET as bit 3 in register 02h.
Rev. 1.2 (02-10-11) Section A.8, "Delta from Rev
B (Mask B0) to Rev C (Mask
B1)"
Added.
Table 3-2, "Electrical Specifications"
PSR improvements made in functional revision B.
Changed PSR spec from ±100 typ and ±200 max
counts / V to ±3 and ±10 counts / V. Conditions
updated.
Section 5.2.2, "Recalibrating
Sensor Inputs"
Added more detail with subheadings for each type of
recalibration.
Section 6.6, "Configuration
Registers"
Added bit 5 BLK_PWR_CTRL to the Configuration 2
Register 44h.
The TIMEOUT bit is set to ‘1’ by default for functional
revision B and is set to ‘0’ by default for functional
revision C.
Section 6.28, "Revision Register"
Updated revision ID in register FFh from 81h to 82h.
Rev. 1.1 (11-17-10) Document Updated for functional revision B. See Section A.7,
"Delta from Rev A (Mask A0) to Rev B (Mask B0)".
Cover Added to General Description: “includes circuitry and
support for enhanced sensor proximity detection.”
Added the following Features:
Calibrates for Parasitic Capacitance
Analog Filtering for System Noise Sources
Press and Hold feature for Volume-like Applications
Table 3-2, "Electrical Specifications"
Conditions for Power Supply Rejection modified adding
the following:
Sampling time = 2.56ms
Averaging = 1
Negative Delta Counts = Disabled
All other parameters default
Section 6.11, "Calibration Activate
Register"
Updated register description to indicate which re-calibration
routine is used.
Section 6.14, "Multiple Touch
Configuration Register"
Updated register description to indicate what will
happen.
Table 6-34, "CSx_BN_TH Bit
Decode"
Table heading changed from “Threshold Divide Setting”
to “Percent Threshold Setting”.
Rev. 1.0 (06-14-10) Initial release
Revision Section/Figure/Entry Correction
2015 Microchip Technology Inc. DS00001624B-page 45
CAP1106
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Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains
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Microchip’s customer notification service helps keep customers current on Microchip products. Subscribers will receive
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To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification”
and follow the registration instructions.
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
• Local Sales Office
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Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://www.microchip.com/support
CAP1106
DS00001624B-page 46 2015 Microchip Technology Inc.
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. [X] - [X] - XXX - [X](1)
l l l l l
Device Temperature Addressing Package Tape and Reel
Range Option Option
Example:
Note 1: Tape and Reel identifier only appears in the catalog part number description. This identifier is used for ordering
purposes and is not printed on the device package. Check with your Microchip Sales Office for package availability
with the Tape and Reel option.
Device: CAP1106
Temperature
Range:
Blank = 0°C to +85°C (Extended Commercial)
Package: AIA = DFN
Tape and
Reel Option:
TR = Tape and Reel(1)
CAP1106-1-AIA-TR
10-pin DFN 3mm x 3mm (RoHS compliant)
Six capacitive touch sensor inputs, SMBus
interface
Reel size is 4,000 pieces
2015 Microchip Technology Inc. DS00001624B-page 47
CAP1106
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device applications and the like is provided only for your convenience and may be
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Trademarks
The Microchip name and logo, the Microchip logo, dsPIC, FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer, LANCheck,
MediaLB, MOST, MOST logo, MPLAB, OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC, SST, SST Logo, SuperFlash and
UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are registered trademarks of Microchip Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit Serial
Programming, ICSP, Inter-Chip Connectivity, KleerNet, KleerNet logo, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK,
MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, RightTouch logo, REAL ICE, SQI, Serial
Quad I/O, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.
Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.
GestIC is a registered trademarks of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in
other countries.
All other trademarks mentioned herein are property of their respective companies.
© 2015, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
ISBN: 9781632770349
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QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
2015 Microchip Technology Inc. DS00001624B-page 48
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2015 Microchip Technology Inc. DS00001623B-page 1
General Description
The CAP1126, which incorporates RightTouch® technology,
is a multiple channel Capacitive Touch sensor
with multiple power LED drivers. It contains six (6) individual
capacitive touch sensor inputs with programmable
sensitivity for use in touch sensor applications.
Each sensor input automatically recalibrates to compensate
for gradual environmental changes.
The CAP1126 also contains two (2) LED drivers that
offer full-on / off, variable rate blinking, dimness controls,
and breathing. Each of the LED drivers may be
linked to one of the sensor inputs to be actuated when
a touch is detected. As well, each LED driver may be
individually controlled via a host controller.
The CAP1126 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons
to be touched simultaneously. If this pattern is
detected, then a status bit is set and an interrupt generated.
Additionally, the CAP1126 includes circuitry and support
for enhanced sensor proximity detection.
The CAP1126 offers multiple power states operating at
low quiescent currents. In the Standby state of operation,
one or more capacitive touch sensor inputs are
active and all LEDs may be used. If a touch is detected,
it will wake the system using the WAKE/SPI_MOSI pin.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor
inputs are active. Driving the WAKE/SPI_MOSI pin or
communications will wake the device.
Applications
• Desktop and Notebook PCs
• LCD Monitors
• Consumer Electronics
• Appliances
Features
• Six (6) Capacitive Touch Sensor Inputs
- Programmable sensitivity
- Automatic recalibration
- Individual thresholds for each button
• Proximity Detection
• Multiple Button Pattern Detection
• Calibrates for Parasitic Capacitance
• Analog Filtering for System Noise Sources
• Press and Hold feature for Volume-like Applications
• Multiple Communication Interfaces
- SMBus / I2C compliant interface
- SPI communications
- Pin selectable communications protocol and
multiple slave addresses (SMBus / I2C only)
• Low Power Operation
- 5uA quiescent current in Deep Sleep
- 50uA quiescent current in Standby (1 sensor
input monitored)
- Samples one or more channels in Standby
• Two (2) LED Driver Outputs
- Open Drain or Push-Pull
- Programmable blink, breathe, and dimness
controls
- Can be linked to Capacitive Touch Sensor
inputs
• Dedicated Wake output flags touches in low
power state
• System RESET pin
• Available in 16-pin 4mm x 4mm RoHS compliant
QFN package
CAP1126
6 Channel Capacitive Touch Sensor with 2 LED Drivers
CAP1126
DS00001623B-page 2 2015 Microchip Technology Inc.
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2015 Microchip Technology Inc. DS00001623B-page 3
CAP1126
Table of Contents
1.0 Block Diagram ................................................................................................................................................................................. 4
2.0 Pin Description ................................................................................................................................................................................ 5
3.0 Electrical Specifications .................................................................................................................................................................. 9
4.0 Communications ........................................................................................................................................................................... 12
5.0 General Description ...................................................................................................................................................................... 23
6.0 Register Description ...................................................................................................................................................................... 29
7.0 Package Information ..................................................................................................................................................................... 67
Appendix A: Device Delta ................................................................................................................................................................... 72
Appendix B: Data Sheet Revision History ........................................................................................................................................... 74
The Microchip Web Site ...................................................................................................................................................................... 76
Customer Change Notification Service ............................................................................................................................................... 76
Customer Support ............................................................................................................................................................................... 76
Product Identification System ............................................................................................................................................................. 77
CAP1126
DS00001623B-page 4 2015 Microchip Technology Inc.
1.0 BLOCK DIAGRAM
SMBus /
BC-Link /
SPI Slave
Protocol
SMCLK BC_CLK /
SPI_CLK
SMDATA BC_DATA / SPI_MSIO /
SPI_MISO
VDD GND
ALERT# / BC_IRQ#
Capacitive Touch Sensing Algorithm
LED1
CS1 CS2 CS3 CS4 CS5 CS6
LED Driver, Breathe, and
Dimness control
RESET WAKE / SPI_MOSI
ADDR_COMM
SPI_CS#
LED2
2015 Microchip Technology Inc. DS00001623B-page 5
CAP1126
2.0 PIN DESCRIPTION
FIGURE 2-1: CAP1126 Pin Diagram (16-Pin QFN)
TABLE 2-1: PIN DESCRIPTION FOR CAP1126
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
1 SPI_CS# Active low chip-select for SPI bus DI (5V) Connect to
Ground
2 WAKE / SPI_-
MOSI
WAKE - Active high wake / interrupt output
Standby power state - requires pull-down resistor DO
Pull-down
WAKE - Active high wake input - requires pull-down Resistor
resistor
Deep Sleep power state
DI
SPI_MOSI - SPI Master-Out-Slave-In port when used in
normal mode DI (5V) Connect to
Ground
1
2
3
4
12
11
10
9
16
15
14
13
5
6
7
8
SMCLK / BC_CLK /
SPI_CLK
SMDATA / BC_DATA / SPI_MSIO /
SPI_MISO
WAKE / SPI_MOSI
ADDR_COMM
VDD
CS6
SPI_CS#
CS5
CS1
CS2
CS3
RESET
LED1
LED2
CS4
ALERT# / BC_IRQ#
CAP1126
16 pin QFN
GND
CAP1126
DS00001623B-page 6 2015 Microchip Technology Inc.
3
SMDATA /
SPI_MSIO /
SPI_MISO
SMDATA - Bi-directional, open-drain SMBus data -
requires pull-up resistor DIOD (5V)
n/a
SPI_MSIO - SPI Master-Slave-In-Out bidirectional port
when used in bi-directional mode DIO
SPI_MISO - SPI Master-In-Slave-Out port when used in
normal mode DO
4 SMCLK / SPI_-
CLK
SMCLK - SMBus clock input - requires pull-up resistor DI (5V)
SPI_CLK - SPI clock input DI (5V) n/a
5 LED1
Open drain LED 1 driver (default) OD (5V) Connect to
Ground
Push-pull LED 1 driver DO
leave open or
connect to
Ground
6 LED2
Open drain LED 2 driver (default) OD (5V) Connect to
Ground
Push-pull LED 2 driver DO
leave open or
connect to
Ground
7 RESET Active high soft reset for system - resets all registers to
default values. If not used, connect to ground. DI (5V) Connect to
Ground
8 ALERT#
ALERT# - Active low alert / interrupt output for SMBus
alert or SPI interrupt OD (5V) Connect to
Ground
ALERT# - Active high push-pull alert / interrupt output for
SMBus alert or SPI interrupt DO leave open
9 ADDR_COMM Address / communications select pin - pull-down resistor
determines address / communications mechanism AI n/a
10 CS6 Capacitive Touch Sensor Input 6 AIO Connect to
Ground
11 CS5 Capacitive Touch Sensor Input 5 AIO Connect to
Ground
12 CS4 Capacitive Touch Sensor Input 4 AIO Connect to
Ground
13 CS3 Capacitive Touch Sensor Input 3 AIO Connect to
Ground
14 CS2 Capacitive Touch Sensor Input 2 AIO Connect to
Ground
15 CS1 Capacitive Touch Sensor Input 1 AIO Connect to
Ground
16 VDD Positive Power supply Power n/a
TABLE 2-1: PIN DESCRIPTION FOR CAP1126 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
2015 Microchip Technology Inc. DS00001623B-page 7
CAP1126
APPLICATION NOTE: When the ALERT# pinis configured as an active low output, it will be open drain. When it is
configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1126 is unpowered.
APPLICATION NOTE: The SPI_CS# pin should be grounded when SMBus, or I2C,communications are used.
The pin types are described in Table 2-2. All pins labeled with (5V) are 5V tolerant.
Bottom
Pad GND Ground Power n/a
TABLE 2-2: PIN TYPES
Pin Type Description
Power This pin is used to supply power or ground to the device.
DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
AIO Analog Input / Output -This pin is used as an I/O for analog signals.
DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output,
it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a
pull-up resistor. This pin is 5V tolerant.
DO Push-pull Digital Output - This pin is used as a digital output and can sink and source current.
DIO Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
TABLE 2-1: PIN DESCRIPTION FOR CAP1126 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
CAP1126
DS00001623B-page 8 2015 Microchip Technology Inc.
3.0 ELECTRICAL SPECIFICATIONS
Note 3-1 Stresses above those listed could cause permanent damage to the device. This is a stress rating
only and functional operation of the device at any other condition above those indicated in the
operation sections of this specification is not implied.
Note 3-2 For the 5V tolerant pins that have a pull-up resistor, the voltage difference between V5VT_PIN and VDD
must never exceed 3.6V.
Note 3-3 The Package Power Dissipation specification assumes a recommended thermal via design consisting
of a 3x3 matrix of 0.3mm (12mil) vias at 1.0mm pitch connected to the ground plane with a 2.1mm
x 2.1mm thermal landing.
Note 3-4 Junction to Ambient (θJA) is dependent on the design of the thermal vias. Without thermal vias and
a thermal landing, the θJA is approximately 60°C/W including localized PCB temperature increase.
TABLE 3-1: ABSOLUTE MAXIMUM RATINGS
Voltage on 5V tolerant pins (V5VT_PIN) -0.3 to 5.5 V
Voltage on 5V tolerant pins (|V5VT_PIN - VDD|) Note 3-2 0 to 3.6 V
Voltage on VDD pin -0.3 to 4 V
Voltage on any other pin to GND -0.3 to VDD + 0.3 V
Package Power Dissipation up to TA = 85°C for 16 pin QFN
(see Note 3-3)
0.9 W
Junction to Ambient (θJA) (see Note 3-4) 58 °C/W
Operating Ambient Temperature Range -40 to 125 °C
Storage Temperature Range -55 to 150 °C
ESD Rating, All Pins, HBM 8000 V
2015 Microchip Technology Inc. DS00001623B-page 9
CAP1126
TABLE 3-2: ELECTRICAL SPECIFICATIONS
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
DC Power
Supply Voltage VDD 3.0 3.3 3.6 V
Supply Current
ISTBY 120 170 uA
Standby state active
1 sensor input monitored
No LEDs active
Default conditions (8 avg, 70ms
cycle time)
ISTBY 50 uA
Standby state active
1 sensor input monitored
No LEDs active
1 avg, 140ms cycle time,
IDSLEEP 5 15 uA
Deep Sleep state active
LEDs at 100% or 0% Duty Cycle
No communications
TA < 40°C
3.135 < VDD < 3.465V
IDD 500 600 uA Capacitive Sensing Active
No LEDs active
Capacitive Touch Sensor Inputs
Maximum Base
Capacitance CBASE 50 pF Pad untouched
Minimum Detectable
Capacitive Shift ΔCTOUCH 20 fF
Pad touched - default conditions (1
avg, 35ms cycle time, 1x sensitivity)
Recommended Cap
Shift ΔCTOUCH 0.1 2 pF Pad touched - Not tested
Power Supply Rejection
PSR ±3 ±10 counts /
V
Untouched Current Counts
Base Capacitance 5pF - 50pF
Maximum sensitivity
Negative Delta Counts disabled
All other parameters default
Timing
RESET Pin Delay tRST_DLY 10 ms
Time to communications
ready tCOMM_DLY 15 ms
Time to first conversion
ready tCONV_DLY 170 200 ms
LED Drivers
Duty Cycle DUTYLED 0 100 % Programmable
Drive Frequency fLED 2 kHz
Sinking Current ISINK 24 mA VOL = 0.4
Sourcing Current ISOURCE 24 mA VOH = VDD - 0.4
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
I/O Pins
Output Low Voltage VOL 0.4 V ISINK_IO = 8mA
Output High Voltage VOH VDD - 0.4 V ISOURCE_IO = 8mA
CAP1126
DS00001623B-page 10 2015 Microchip Technology Inc.
Note 3-5 The ALERT pin will not glitch high or low at power up if connected to VDD or another voltage.
Note 3-6 The SMCLK and SMDATA pins will not glitch low at power up if connected to VDD or another voltage.
Input High Voltage VIH 2.0 V
Input Low Voltage VIL 0.8 V
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
RESET Pin Release
to conversion ready tRESET 170 200 ms
SMBus Timing
Input Capacitance CIN 5 pF
Clock Frequency fSMB 10 400 kHz
Spike Suppression tSP 50 ns
Bus Free Time Stop to
Start tBUF 1.3 us
Start Setup Time tSU:STA 0.6 us
Start Hold Time tHD:STA 0.6 us
Stop Setup Time tSU:STO 0.6 us
Data Hold Time tHD:DAT 0 us When transmitting to the master
Data Hold Time tHD:DAT 0.3 us When receiving from the master
Data Setup Time tSU:DAT 0.6 us
Clock Low Period tLOW 1.3 us
Clock High Period tHIGH 0.6 us
Clock / Data Fall Time tFALL 300 ns Min = 20+0.1CLOAD ns
Clock / Data Rise
Time tRISE 300 ns Min = 20+0.1CLOAD ns
Capacitive Load CLOAD 400 pF per bus line
SPI Timing
Clock Period tP 250 ns
Clock Low Period tLOW 0.4 x tP 0.6 x tP ns
Clock High Period tHIGH 0.4 x tP 0.6 x tP ns
Clock Rise / Fall time tRISE / tFALL 0.1 x tP ns
Data Output Delay tD:CLK 10 ns
Data Setup Time tSU:DAT 20 ns
Data Hold Time tHD:DAT 20 ns
SPI_CS# to SPI_CLK
setup time tSU:CS 0 ns
Wake Time tWAKE 10 20 us SPI_CS# asserted to CLK assert
TABLE 3-2: ELECTRICAL SPECIFICATIONS (CONTINUED)
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
2015 Microchip Technology Inc. DS00001623B-page 11
CAP1126
4.0 COMMUNICATIONS
4.1 Communications
The CAP1126communicates using the 2-wire SMBus or I2C bus, the 2-wire proprietary BC-Link, or the SPI bus. If the
proprietary BC-Link protocol is required for your application, please contact your Microchip representative for ordering
instructions. Regardless of communication mechanism, the device functionality remains unchanged. The communications
mechanism as well as the SMBus (or I2C) slave address is determined by the resistor connected between the
ADDR_COMM pin and ground as shown in Table 4-1.
4.1.1 SMBUS (I2C) COMMUNICATIONS
When configured to communicate via the SMBus, the CAP1126 supports the following protocols: Send Byte, Receive
Byte, Read Byte, Write Byte, Read Block, and Write Block. In addition, the device supports I2C formatting for block read
and block write protocols.
APPLICATION NOTE: For SMBus/I2C communications, the SPI_CS# pin is not used and should be grounded; any
data presented to this pin will be ignored.
See Section 4.2 and Section 4.3 for more information on the SMBus bus and protocols respectively.
4.1.2 SPI COMMUNICATIONS
When configured to communicate via the SPI bus, the CAP1126supports both bi-directional 3-wire and normal 4-wire
protocols and uses the SPI_CS# pin to enable communications.
APPLICATION NOTE: See Section 4.5 and Section 4.6 for more information on the SPI bus and protocols
respectively.Upon power up, the CAP1126 will not respond to any communications for up to
15ms. After this time, full functionality is available.
4.2 System Management Bus
The CAP1126 communicates with a host controller, such as an SIO, through the SMBus. The SMBus is a two-wire serial
communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in
Figure 4-1. Stretching of the SMCLK signal is supported; however, the CAP1126 will not stretch the clock signal.
TABLE 4-1: ADDR_COMM PIN DECODE
Pull-Down Resistor (+/- 5%) Protocol Used SMBus Address
GND SPI Communications using Normal
4-wire Protocol Used
n/a
56k SPI Communications using BiDirectional
3-wire Protocol Used
n/a
68k Reserved n/a
82k SMBus / I2C 0101_100(r/w)
100k SMBus / I2C 0101_011(r/w)
120k SMBus / I2C 0101_010(r/w)
150k SMBus / I2C 0101_001(r/w)
VDD SMBus / I2C 0101_000(r/w)
CAP1126
DS00001623B-page 12 2015 Microchip Technology Inc.
4.2.1 SMBUS START BIT
The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the
SMBus Clock line is in a logic ‘1’ state.
4.2.2 SMBUS ADDRESS AND RD / WR BIT
The SMBus Address Byte consists of the 7-bit slave address followed by the RD / WR indicator bit. If this RD / WR bit
is a logic ‘0’, then the SMBus Host is writing data to the slave device. If this RD / WR bit is a logic ‘1’, then the SMBus
Host is reading data from the slave device.
See Table 4-1 for available SMBus addresses.
4.2.3 SMBUS DATA BYTES
All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.
4.2.4 SMBUS ACK AND NACK BITS
The SMBus slave will acknowledge all data bytes that it receives. This is done by the slave device pulling the SMBus
Data line low after the 8th bit of each byte that is transmitted. This applies to both the Write Byte and Block Write protocols.
The Host will NACK (not acknowledge) the last data byte to be received from the slave by holding the SMBus data line
high after the 8th data bit has been sent. For the Block Read protocol, the Host will ACK each data byte that it receives
except the last data byte.
4.2.5 SMBUS STOP BIT
The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the
SMBus clock line is in a logic ‘1’ state. When the CAP1126 detects an SMBus Stop bit and it has been communicating
with the SMBus protocol, it will reset its slave interface and prepare to receive further communications.
4.2.6 SMBUS TIMEOUT
The CAP1126 includes an SMBus timeout feature. Following a 30ms period of inactivity on the SMBus where the
SMCLK pin is held low, the device will timeout and reset the SMBus interface.
The timeout function defaults to disabled. It can be enabled by setting the TIMEOUT bit in the Configuration register
(see Section 6.6, "Configuration Registers").
4.2.7 SMBUS AND I2C COMPATIBILITY
The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus
2.0 and I2C specifications. For information on using the CAP1126 in an I2C system, refer to AN 14.0 Dedicated Slave
Devices in I2C Systems.
FIGURE 4-1: SMBus Timing Diagram
SMDATA
SMCLK
TLOW
TRISE
THIGH
TFALL
TBUF
THD:STA
P S S - Start Condition P - Stop Condition
THD:DAT TSU:DAT TSU:STA
THD:STA
P
TSU:STO
S
2015 Microchip Technology Inc. DS00001623B-page 13
CAP1126
1. CAP1126 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz.
2. Minimum frequency for SMBus communications is 10kHz.
3. The SMBus slave protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality
is disabled by default in the CAP1126 and can be enabled by writing to the TIMEOUT bit. I2C does not have
a timeout.
4. The SMBus slave protocol will reset if both the clock and data lines are held at a logic ‘1’ for longer than 200µs
(idle condition). This function is disabled by default in the CAP1126 and can be enabled by writing to the TIMEOUT
bit. I2C does not have an idle condition.
5. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus).
6. I2C devices support block read and write differently. I2C protocol allows for unlimited number of bytes to be sent
in either direction. The SMBus protocol requires that an additional data byte indicating number of bytes to read /
write is transmitted. The CAP1126 supports I2C formatting only.
4.3 SMBus Protocols
The CAP1126 is SMBus 2.0 compatible and supports Write Byte, Read Byte, Send Byte, and Receive Byte as valid
protocols as shown below.
All of the below protocols use the convention in Table 4-2.
4.3.1 SMBUS WRITE BYTE
The Write Byte is used to write one byte of data to a specific register as shown in Table 4-3.
4.3.2 SMBUS READ BYTE
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4-4.
4.3.3 SMBUS SEND BYTE
The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is
transferred during the Send Byte protocol as shown in Table 4-5.
APPLICATION NOTE: The Send Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
TABLE 4-2: PROTOCOL FORMAT
Data Sent to
Device
Data Sent to the
HOst
Data sent Data sent
TABLE 4-3: WRITE BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK Stop
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0 0 -> 1
TABLE 4-4: READ BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data NACK Stop
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-5: SEND BYTE PROTOCOL
Start Slave Address WR ACK Register Address ACK Stop
1 -> 0 YYYY_YYY 0 0 XXh 0 0 -> 1
CAP1126
DS00001623B-page 14 2015 Microchip Technology Inc.
4.3.4 SMBUS RECEIVE BYTE
The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to
be at the right location (e.g., set via Send Byte). This is used for consecutive reads of the same register as shown in
Table 4-6.
APPLICATION NOTE: The Receive Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.4 I2C Protocols
The CAP1126 supports I2C Block Write and Block Read.
The protocols listed below use the convention in Table 4-2.
4.4.1 BLOCK WRITE
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in Table 4-7.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.4.2 BLOCK READ
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in Table 4-8.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.5 SPI Interface
The SMBus has a predefined packet structure, the SPI does not. The SPI Bus can operate in two modes of operation,
normal 4-wire mode and bi-directional 3-wire mode. All SPI commands consist of 8-bit packets sent to a specific slave
device (identified by the CS pin).
The SPI bus will latch data on the rising edge of the clock and the clock and data both idle high.
All commands are supported via both operating modes. The supported commands are: Reset Serial interface, set
address pointer, write command and read command. Note that all other codes received during the command phase are
ignored and have no effect on the operation of the device.
TABLE 4-6: RECEIVE BYTE PROTOCOL
Start Slave Address RD ACK Register Data NACK Stop
1 -> 0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-7: BLOCK WRITE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0
Register Data ACK Register
Data
ACK . . . Register
Data
ACK Stop
XXh 0 XXh 0 . . . XXh 0 0 -> 1
TABLE 4-8: BLOCK READ PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh
ACK Register
Data
ACK Register
Data
ACK Register
Data
ACK . . . Register
Data
NACK Stop
0 XXh 0 XXh 0 XXh 0 . . . XXh 1 0 -> 1
2015 Microchip Technology Inc. DS00001623B-page 15
CAP1126
4.5.1 SPI NORMAL MODE
The SPI Bus can operate in two modes of operation, normal and bi-directional mode. In the normal mode of operation,
there are dedicated input and output data lines. The host communicates by sending a command along the CAP1126
SPI_MOSI data line and reading data on the SPI_MISO data line. Both communications occur simultaneously which
allows for larger throughput of data transactions.
All basic transfers consist of two 8 bit transactions from the Master device while the slave device is simultaneously sending
data at the current address pointer value.
Data writes consist of two or more 8-bit transactions. The host sends a specific write command followed by the data to
write the address pointer. Data reads consist of one or more 8-bit transactions. The host sends the specific read data
command and continues clocking for as many data bytes as it wishes to receive.
4.5.2 SPI BI-DIRECTIONAL MODE
In the bi-directional mode of operation, the SPI data signals are combined into the SPI_MSIO line, which is shared for
data received by the device and transmitted by the device. The protocol uses a simple handshake and turn around
sequence for data communications based on the number of clocks transmitted during each phase.
All basic transfers consist of two 8 bit transactions. The first is an 8 bit command phase driven by the Master device.
The second is by an 8 bit data phase driven by the Master for writes, and by the CAP1126 for read operations.
The auto increment feature of the address pointer allows for successive reads or writes. The address pointer will return
to 00h after reaching FFh.
4.5.3 SPI_CS# PIN
The SPI Bus is a single master, multiple slave serial bus. Each slave has a dedicated CS pin (chip select) that the master
asserts low to identify that the slave is being addressed. There are no formal addressing options.
4.5.4 ADDRESS POINTER
All data writes and reads are accessed from the current address pointer. In both Bi-directional mode and Full Duplex
mode, the Address pointer is automatically incremented following every read command or every write command.
The address pointer will return to 00h after reaching FFh.
4.5.5 SPI TIMEOUT
The CAP1126 does not detect any timeout conditions on the SPI bus.
FIGURE 4-2: SPI Timing
SPI_MSIO or
SPI_MOSI or
SPI_MISO
SPI_CLK
tLOW
tRISE
tHIGH
tFALL
tD:CLK tHD:DAT
tSU:DAT
tP
2015 Microchip Technology Inc. DS00001623B-page 16
CAP1126 4.6 Normal SPI Protocols When operating in normal mode, the SPI bus internal address pointer is incremented depending upon which command has been transmitted. Multiple commands may be transmitted sequentually so long as the SPI_CS# pin is asserted low. Figure 4-3 shows an example of this operation.
4.6.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the transaction - command or data, the receipt of the
successive reset commands resets the Serial communication interface only. All other functions are not affected by the reset operation.
FIGURE 4-3: Example SPI Bus Communication - Normal Mode
SPI_CS#
SPI_MISO
SPI_MOSI
SPI Address Pointer
SPI Data output buffer
Register Address /
Data
7Ah
XXh
(invalid)
XXh
(invalid)
YYh
(invalid)
7Ah 7Dh 41h
YYh
(invalid)
7Eh 66h
XXh
(invalid) 45h
7Dh 41h
AAh
(invalid)
AAh
(invalid)
7Fh 7Fh
55h
(invalid) 66h
7Fh
AAh
7Dh
43h
40h
78h
7Fh
XXh
(invalid)
7Fh
56h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
45h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
55h
7Fh
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
66h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
44h
80h
40h
80h
40h
56h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
43h
55h
7Fh 7Fh
55h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
80h
45h
43h
46h
78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
00h
XXh
Indicates SPI Address pointer incremented
2015 Microchip Technology Inc. DS00001623B-page 17
CAP1126
4.6.2 SET ADDRESS POINTER
The Set Address Pointer command sets the Address pointer for subsequent reads and writes of data. The pointer is set
on the rising edge of the final data bit. At the same time, the data that is to be read is fetched and loaded into the internal
output buffer but is not transmitted.
4.6.3 WRITE DATA
The Write Data protocol updates the contents of the register referenced by the address pointer. As the command is processed,
the data to be read is fetched and loaded into the internal output buffer but not transmitted. Then, the register
is updated with the data to be written. Finally, the address pointer is incremented.
FIGURE 4-4: SPI Reset Interface Command - Normal Mode
FIGURE 4-5: SPI Set Address Pointer Command - Normal Mode
Master SPDOUT
SPI_MOSI
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
Invalid register data 00h – Internal Data buffer empty SPI_MISO
Master Drives Slave Drives
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’
Master SPDOUT
SPI_MOSI Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
SPI_MISO Unknown, Invalid Data Unknown, Invalid Data
Master Drives Slave Drives Address pointer set
‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1126
DS00001623B-page 18 2015 Microchip Technology Inc.
4.6.4 READ DATA
The Read Data protocol is used to read data from the device. During the normal mode of operation, while the device is
receiving data, the CAP1126 is simultaneously transmitting data to the host. For the Set Address commands and the
Write Data commands, this data may be invalid and it is recommended that the Read Data command is used.
FIGURE 4-6: SPI Write Command - Normal Mode
FIGURE 4-7: SPI Read Command - Normal Mode
Master SPDOUT
SPI_MOSI Data to Write
SPI_CS#
SPI_CLK
Write Command – 7Eh
Unknown, Invalid Data Old Data at Current Address Pointer SPI_MISO
Master Drives Slave Drives
1. Data written at current
address pointer
2. Address pointer incremented
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
First Read Command – 7Fh
SPI_CS#
SPI_MISO Invalid, Unknown Data *
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Subsequent Read
Commands – 7F
Data at Current Address Pointer
Address Pointer
Incremented **
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
* The first read command after any other command will return invalid data for the first
byte. Subsequent read commands will return the data at the Current Address Pointer
** The Address Pointer is incremented 8 clocks after the Read Command has been
received. Therefore continually sending Read Commands will result in each command
reporting new data. Once Read Commands have been finished, the last data byte will be
read during the next 8 clocks for any command
2015 Microchip Technology Inc. DS00001623B-page 19
CAP1126
4.7 Bi-Directional SPI Protocols
4.7.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the
transaction - command or data, the receipt of the successive reset commands resets the Serial communication interface
only. All other functions are not affected by the reset operation.
4.7.2 SET ADDRESS POINTER
Sets the address pointer to the register to be accessed by a read or write command. This command overrides the autoincrementing
of the address pointer.
FIGURE 4-8: SPI Read Command - Normal Mode - Full
FIGURE 4-9: SPI Reset Interface Command - Bi-directional Mode
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
Read Command – 7Fh
SPI_CS#
Data at previously set register address = current
address pointer
SPI_MISO ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
XXh
1. Register Read Address
updated to Current SPI Read
Address pointer
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous address
pointer + 1 = current address
pointer
1. Register Read Address
incremented = current address
pointer + 1
1. SPI Read Address
Incremented = new current
address pointer
2. Register Read Address
Incremented = current address
pointer +1
Register Data loaded into
Output buffer = data at current
address pointer + 1
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous register
address pointer + 1 = current
address pointer
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
Subsequent Read Commands – 7Fh
1. Register Read Address
updated to Current SPI Read
Address pointer.
2. Register Read Address
incremented = current address
pointer +1 – end result =
register address pointer doesn’t
change
Master SPDOUT
SPI_MSIO
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1126
DS00001623B-page 20 2015 Microchip Technology Inc.
4.7.3 WRITE DATA
Writes data value to the register address stored in the address pointer. Performs auto increment of address pointer after
the data is loaded into the register.
4.7.4 READ DATA
Reads data referenced by the address pointer. Performs auto increment of address pointer after the data is transferred
to the Master.
FIGURE 4-10: SPI Set Address Pointer Command - Bi-directional Mode
FIGURE 4-11: SPI Write Data Command - Bi-directional Mode
FIGURE 4-12: SPI Read Data Command - Bi-directional Mode
Master SPDOUT
SPI_MSIO Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
‘0’ ‘1’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Master SPDOUT
SPI_MSIO Register Write Data
SPI_CS#
SPI_CLK
Write Command – 7Eh
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’
Master SPDOUT
SPI_MSIO
Master Drives Slave Drives Indeterminate
Register Read Data
SPI_CLK
Read Command – 7Fh
SPI_CS#
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
2015 Microchip Technology Inc. DS00001623B-page 21
CAP1126
4.8 BC-Link Interface
The BC-Link is a proprietary bus developed to allow communication between a host controller device to a companion
device. This device uses this serial bus to read and write registers and for interrupt processing. The interface uses a
data port concept, where the base interface has an address register, data register and a control register, defined in the
8051’s SFR space.
Refer to documentation for the BC-Link compatible host controller for details on how to access the CAP1126 via the BCLink
Interface.
CAP1126
DS00001623B-page 22 2015 Microchip Technology Inc.
5.0 GENERAL DESCRIPTION
The CAP1126 is a multiple channel Capacitive Touch sensor with multiple power LED drivers. It contains six (6) individual
capacitive touch sensor inputs with programmable sensitivity for use in touch sensor applications. Each sensor input
automatically recalibrates to compensate for gradual environmental changes.
The CAP1126 also contains two (2) low side (or push-pull) LED drivers that offer full-on / off, variable rate blinking, dimness
controls, and breathing. Each of the LED drivers may be linked to one of the sensor inputs to be actuated when a
touch is detected. As well, each LED driver may be individually controlled via a host controller.
Finally, the device contains a dedicated RESET pin to act as a soft reset by the system.
The CAP1126 offers multiple power states. It operates at the lowest quiescent current during its Deep Sleep state. In
the low power Standby state, it can monitor one or more channels and respond to communications normally. The device
contains a wake pin (WAKE/SPI_MOSI) output to wake the system when a touch is detected in Standby and to wake
the device from Deep Sleep.
The device communicates with a host controller using the SPI bus, or via SMBus / I2C. The host controller may poll the
device for updated information at any time or it may configure the device to flag an interrupt whenever a touch is
detected on any sensor pad.
A typical system diagram is shown in Figure 5-1.
2015 Microchip Technology Inc. DS00001623B-page 23
CAP1126
5.1 Power States
The CAP1126 has three operating states depending on the status of the STBY and DSLEEP bits. When the device transitions
between power states, previously detected touches (for inactive channels) are cleared and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active capacitive sensor inputs and driving all LED channels
as defined.
2. Standby - The device is in a lower power state. It will measure a programmable number of channels using the
Standby Configuration controls (see Section 6.20 through Section 6.22). Interrupts will still be generated based
on the active channels. The device will still respond to communications normally and can be returned to the Fully
Active state of operation by clearing the STBY bit.
FIGURE 5-1: System Diagram for CAP1126
CAP1126
CS6
SMDATA / BC_DATA / SPI_MSIO / SPI_MISO
SMCLK / BC_CLK / SPI_CLK
VDD Embedded Controller ALERT# / BC_IRQ#
CS4
CS2
3.3V – 5V
CS5
CS3
CS1
WAKE / SPI_MOSI
RESET
SPI_CS#
ADDR_COMM
LED1 LED2
3.3V – 5V
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
CAP1126
DS00001623B-page 24 2015 Microchip Technology Inc.
3. Deep Sleep - The device is in its lowest power state. It is not monitoring any capacitive sensor inputs and not
driving any LEDs. All LEDs will be driven to their programmed non-actuated state and no PWM operations will
be done. While in Deep Sleep, the device can be awakened by SMBus or SPI communications targeting the
device. This will not cause the DSLEEP to be cleared so the device will return to Deep Sleep once all communications
have stopped.
If the device is not communicating via the 4-wire SPI bus, then during this state of operation, if the WAKE/SPI_MOSI
pin is driven high by an external source, the device will clear the DSLEEP bit and return to Fully Active.
APPLICATION NOTE: In the Deep Sleep state, the LED output will be either high or low and will not be PWM’d at
the min or max duty cycle.
5.2 RESET Pin
The RESET pin is an active high reset that is driven from an external source. While it is asserted high, all the internal
blocks will be held in reset including the communications protocol used. No capacitive touch sensor inputs will be sampled
and the LEDs will not be driven. All configuration settings will be reset to default states and all readings will be
cleared.
The device will be held in Deep Sleep that can only be removed by driving the RESET pin low. This will cause the
RESET status bit to be set to a logic ‘1’ and generate an interrupt.
5.3 WAKE/SPI_MOSI Pin Operation
The WAKE / SPI_MOSI pin is a multi-function pin depending on device operation. When the device is configured to communicate
using the 4-wire SPI bus, this pin is an input.
However, when the CAP1126 is placed in Standby and is not communicating using the 4-wire SPI protocol, the WAKE
pin is an active high output. In this condition, the device will assert the WAKE/SPI_MOSI pin when a touch is detected
on one of its sampled sensor inputs. The pin will remain asserted until the INT bit has been cleared and then it will be
de-asserted.
When the CAP1126 is placed in Deep Sleep and it is not communicating using the 4-wire SPI protocol, the WAKE/SPI_-
MOSI pin is monitored by the device as an input. If the WAKE/SPI_MOSI pin is driven high by an external source, the
CAP1126will clear the DSLEEP bit causing the device to return to Fully Active.
When the device is placed in Deep Sleep, this pin is a High-Z input and must have a pull-down resistor to GND for proper
operation.
5.4 LED Drivers
The CAP1126 contains two (2) LED drivers. Each LED driver can be linked to its respective capacitive touch sensor
input or it can be controlled by the host. Each LED driver can be configured to operate in one of the following modes
with either push-pull or open drain drive.
1. Direct - The LED is configured to be on or off when the corresponding input stimulus is on or off (or inverted). The
brightness of the LED can be programmed from full off to full on (default). Additionally, the LED contains controls
to individually configure ramping on, off, and turn-off delay.
2. Pulse 1 - The LED is configured to “Pulse” (transition ON-OFF-ON) a programmable number of times with programmable
rate and min / max brightness. This behavior may be actuated when a press is detected or when a
release is detected.
3. Pulse 2 - The LED is configured to “Pulse” while actuated and then “Pulse” a programmable number of times with
programmable rate and min / max brightness when the sensor pad is released.
4. Breathe - The LED is configured to transition continuously ON-OFF-ON (i.e. to “Breathe”) with a programmable
rate and min / max brightness.
When an LED is not linked to a sensor and is actuated by the host, there’s an option to assert the ALERT# pin when
the initiated LED behavior has completed.
5.4.1 LINKING LEDS TO CAPACITIVE TOUCH SENSOR INPUTS
All LEDs can be linked to the corresponding capacitive touch sensor input so that when the sensor input detects a touch,
the corresponding LED will be actuated at one of the programmed responses.
2015 Microchip Technology Inc. DS00001623B-page 25
CAP1126
5.5 Capacitive Touch Sensing
The CAP1126 contains six (6) independent capacitive touch sensor inputs. Each sensor input has dynamic range to
detect a change of capacitance due to a touch. Additionally, each sensor input can be configured to be automatically
and routinely re-calibrated.
5.5.1 SENSING CYCLE
Each capacitive touch sensor input has controls to be activated and included in the sensing cycle. When the device is
active, it automatically initiates a sensing cycle and repeats the cycle every time it finishes. The cycle polls through each
active sensor input starting with CS1 and extending through CS6. As each capacitive touch sensor input is polled, its
measurement is compared against a baseline “Not Touched” measurement. If the delta measurement is large enough,
a touch is detected and an interrupt is generated.
The sensing cycle time is programmable (see Section 6.10, "Averaging and Sampling Configuration Register").
5.5.2 RECALIBRATING SENSOR INPUTS
There are various options for recalibrating the capacitive touch sensor inputs. Recalibration re-sets the Base Count Registers
(Section 6.24, "Sensor Input Base Count Registers") which contain the “not touched” values used for touch detection
comparisons.
APPLICATION NOTE: The device will recalibrate all sensor inputs that were disabled when it transitions from
Standby. Likewise, the device will recalibrate all sensor inputs when waking out of Deep
Sleep.
5.5.2.1 Manual Recalibration
The Calibration Activate Registers (Section 6.11, "Calibration Activate Register") force recalibration of selected sensor
inputs. When a bit is set, the corresponding capacitive touch sensor input will be recalibrated (both analog and digital).
The bit is automatically cleared once the recalibration routine has finished.
5.5.2.2 Automatic Recalibration
Each sensor input is regularly recalibrated at a programmable rate (see Section 6.17, "Recalibration Configuration Register").
By default, the recalibration routine stores the average 64 previous measurements and periodically updates the
base “not touched” setting for the capacitive touch sensor input.
5.5.2.3 Negative Delta Count Recalibration
It is possible that the device loses sensitivity to a touch. This may happen as a result of a noisy environment, an accidental
recalibration during a touch, or other environmental changes. When this occurs, the base untouched sensor input
may generate negative delta count values. The NEG_DELTA_CNT bits (see Section 6.17, "Recalibration Configuration
Register") can be set to force a recalibration after a specified number of consecutive negative delta readings.
5.5.2.4 Delayed Recalibration
It is possible that a “stuck button” occurs when something is placed on a button which causes a touch to be detected
for a long period. By setting the MAX_DUR_EN bit (see Section 6.6, "Configuration Registers"), a recalibration can be
forced when a touch is held on a button for longer than the duration specified in the MAX_DUR bits (see Section 6.8,
"Sensor Input Configuration Register").
Note: During this recalibration routine, the sensor inputs will not detect a press for up to 200ms and the Sensor
Base Count Register values will be invalid. In addition, any press on the corresponding sensor pads will
invalidate the recalibration.
Note: Automatic recalibration only works when the delta count is below the active sensor input threshold. It is disabled
when a touch is detected.
Note: During this recalibration, the device will not respond to touches.
CAP1126
DS00001623B-page 26 2015 Microchip Technology Inc.
5.5.3 PROXIMITY DETECTION
Each sensor input can be configured to detect changes in capacitance due to proximity of a touch. This circuitry detects
the change of capacitance that is generated as an object approaches, but does not physically touch, the enabled sensor
pad(s). When a sensor input is selected to perform proximity detection, it will be sampled from 1x to 128x per sampling
cycle. The larger the number of samples that are taken, the greater the range of proximity detection is available at the
cost of an increased overall sampling time.
5.5.4 MULTIPLE TOUCH PATTERN DETECTION
The multiple touch pattern (MTP) detection circuitry can be used to detect lid closure or other similar events. An event
can be flagged based on either a minimum number of sensor inputs or on specific sensor inputs simultaneously exceeding
an MTP threshold or having their Noise Flag Status Register bits set. An interrupt can also be generated. During an
MTP event, all touches are blocked (see Section 6.15, "Multiple Touch Pattern Configuration Register").
5.5.5 LOW FREQUENCY NOISE DETECTION
Each sensor input has an EMI noise detector that will sense if low frequency noise is injected onto the input with sufficient
power to corrupt the readings. If this occurs, the device will reject the corrupted sample and set the corresponding
bit in the Noise Status register to a logic ‘1’.
5.5.6 RF NOISE DETECTION
Each sensor input contains an integrated RF noise detector. This block will detect injected RF noise on the CS pin. The
detector threshold is dependent upon the noise frequency. If RF noise is detected on a CS line, that sample is removed
and not compared against the threshold.
5.6 ALERT# Pin
The ALERT# pin is an active low (or active high when configured) output that is driven when an interrupt event is
detected.
Whenever an interrupt is generated, the INT bit (see Section 6.1, "Main Control Register") is set. The ALERT# pin is
cleared when the INT bit is cleared by the user. Additionally, when the INT bit is cleared by the user, status bits are only
cleared if no touch is detected.
5.6.1 SENSOR INTERRUPT BEHAVIOR
The sensor interrupts are generated in one of two ways:
1. An interrupt is generated when a touch is detected and, as a user selectable option, when a release is detected
(by default - see Section 6.6). See Figure 5-3.
2. If the repeat rate is enabled then, so long as the touch is held, another interrupt will be generated based on the
programmed repeat rate (see Figure 5-2).
When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch
is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button
is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a
touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it
is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed
repeat rate and upon release (if enabled).
APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon
sensor pad release and an active-low ALERT# pin.
APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.
Note: Delayed recalibration only works when the delta count is above the active sensor input threshold. If
enabled, it is invoked when a sensor pad touch is held longer than the MAX_DUR bit setting.
2015 Microchip Technology Inc. DS00001623B-page 27
CAP1126
FIGURE 5-2: Sensor Interrupt Behavior - Repeat Rate Enabled
FIGURE 5-3: Sensor Interrupt Behavior - No Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms)
Min Press Setting
(280ms)
Interrupt on
Touch
Button Repeat Rate
(175ms)
Button Repeat Rate
(175ms)
Interrupt on
Release
(optional)
ALERT# pin
(active low)
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms) Interrupt on
Touch Interrupt on
Release
(optional)
ALERT# pin
(active low)
CAP1126
DS00001623B-page 28 2015 Microchip Technology Inc.
6.0 REGISTER DESCRIPTION
The registers shown in Table 6-1 are accessible through the communications protocol. An entry of ‘-’ indicates that the
bit is not used and will always read ‘0’.
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER
Register
Address R/W Register Name Function Default Value Page
00h R/W Main Control Controls general power states and
power dissipation 00h Page 31
02h R General Status Stores general status bits 00h Page 32
03h R Sensor Input Status Returns the state of the sampled
capacitive touch sensor inputs 00h Page 32
04h R LED Status Stores status bits for LEDs 00h Page 32
0Ah R Noise Flag Status Stores the noise flags for sensor inputs 00h Page 33
10h R Sensor Input 1 Delta
Count Stores the delta count for CS1 00h Page 33
11h R Sensor Input 2 Delta
Count Stores the delta count for CS2 00h Page 33
12h R Sensor Input 3 Delta
Count Stores the delta count for CS3 00h Page 33
13h R Sensor Input 4 Delta
Count Stores the delta count for CS4 00h Page 33
14h R Sensor Input 5 Delta
Count Stores the delta count for CS5 00h Page 33
15h R Sensor Input 6 Delta
Count Stores the delta count for CS6 00h Page 33
1Fh R/W Sensitivity Control
Controls the sensitivity of the threshold
and delta counts and data scaling of
the base counts
2Fh Page 33
20h R/W Configuration Controls general functionality 20h Page 35
21h R/W Sensor Input Enable Controls whether the capacitive touch
sensor inputs are sampled 3Fh Page 36
22h R/W Sensor Input Configuration
Controls max duration and auto-repeat
delay for sensor inputs operating in the
full power state
A4h Page 36
23h R/W Sensor Input Configuration
2
Controls the MPRESS controls for all
sensor inputs 07h Page 38
24h R/W Averaging and Sampling
Config
Controls averaging and sampling window
39h Page 38
26h R/W Calibration Activate Forces re-calibration for capacitive
touch sensor inputs 00h Page 39
27h R/W Interrupt Enable Enables Interrupts associated with
capacitive touch sensor inputs 3Fh Page 40
28h R/W Repeat Rate Enable Enables repeat rate for all sensor
inputs 3Fh Page 40
2Ah R/W Multiple Touch Configuration
Determines the number of simultaneous
touches to flag a multiple touch
condition
80h Page 41
2Bh R/W Multiple Touch Pattern
Configuration
Determines the multiple touch pattern
(MTP) configuration 00h Page 41
2015 Microchip Technology Inc. DS00001623B-page 29
CAP1126
2Dh R/W Multiple Touch Pattern
Determines the pattern or number of
sensor inputs used by the MTP circuitry
3Fh Page 42
2Fh R/W Recalibration Configuration
Determines re-calibration timing and
sampling window 8Ah Page 43
30h R/W Sensor Input 1 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 1
40h Page 44
31h R/W Sensor Input 2 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 2
40h Page 44
32h R/W Sensor Input 3 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 3
40h Page 44
33h R/W Sensor Input 4 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 4
40h Page 44
34h R/W Sensor Input 5 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 5
40h Page 44
35h R/W Sensor Input 6 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 6
40h Page 44
38h R/W Sensor Input Noise
Threshold
Stores controls for selecting the noise
threshold for all sensor inputs 01h Page 44
Standby Configuration Registers
40h R/W Standby Channel Controls which sensor inputs are
enabled while in standby 00h Page 45
41h R/W Standby Configuration Controls averaging and cycle time
while in standby 39h Page 45
42h R/W Standby Sensitivity Controls sensitivity settings used while
in standby 02h Page 47
43h R/W Standby Threshold Stores the touch detection threshold
for active sensor inputs in standby 40h Page 47
44h R/W Configuration 2 Stores additional configuration controls
for the device 40h Page 35
Base Count Registers
50h R Sensor Input 1 Base
Count
Stores the reference count value for
sensor input 1 C8h Page 47
51h R Sensor Input 2 Base
Count
Stores the reference count value for
sensor input 2 C8h Page 47
52h R Sensor Input 3 Base
Count
Stores the reference count value for
sensor input 3 C8h Page 47
53h R Sensor Input 4 Base
Count
Stores the reference count value for
sensor input 4 C8h Page 47
54h R Sensor Input 5 Base
Count
Stores the reference count value for
sensor input 5 C8h Page 47
55h R Sensor Input 6 Base
Count
Stores the reference count value for
sensor input 6 C8h Page 47
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1126
DS00001623B-page 30 2015 Microchip Technology Inc.
LED Controls
71h R/W LED Output Type Controls the output type for the LED
outputs 00h Page 48
72h R/W Sensor Input LED Linking
Controls linking of sensor inputs to
LED channels 00h Page 48
73h R/W LED Polarity Controls the output polarity of LEDs 00h Page 49
74h R/W LED Output Control Controls the output state of the LEDs 00h Page 50
77h R/W Linked LED
Transition Control
Controls the transition when LEDs are
linked to CS channels 00h Page 51
79h R/W LED Mirror Control Controls the mirroring of duty cycles
for the LEDs 00h Page 51
81h R/W LED Behavior 1 Controls the behavior and response of
LEDs 1 - 2 00h Page 51
84h R/W LED Pulse 1 Period Controls the period of each breathe
during a pulse 20h Page 53
85h R/W LED Pulse 2 Period Controls the period of the breathing
during breathe and pulse operation 14h Page 55
86h R/W LED Breathe Period Controls the period of an LED breathe
operation 5Dh Page 56
88h R/W LED Config Controls LED configuration 04h Page 56
90h R/W LED Pulse 1 Duty Cycle Determines the min and max duty
cycle for the pulse operation F0h Page 57
91h R/W LED Pulse 2 Duty Cycle Determines the min and max duty
cycle for breathe and pulse operation F0h Page 57
92h R/W LED Breathe Duty Cycle Determines the min and max duty
cycle for the breathe operation F0h Page 57
93h R/W LED Direct Duty Cycle Determines the min and max duty
cycle for Direct mode LED operation F0h Page 57
94h R/W LED Direct Ramp Rates Determines the rising and falling edge
ramp rates of the LEDs 00h Page 58
95h R/W LED Off Delay Determines the off delay for all LED
behaviors 00h Page 58
B1h R Sensor Input 1 Calibration
Stores the upper 8-bit calibration value
for sensor input 1 00h Page 61
B2h R Sensor Input 2 Calibration
Stores the upper 8-bit calibration value
for sensor input 2 00h Page 61
B3h R Sensor Input 3 Calibration
Stores the upper 8-bit calibration value
for sensor input 3 00h Page 61
B4h R Sensor Input 4 Calibration
Stores the upper 8-bit calibration value
for sensor input 4 00h Page 61
B5h R Sensor Input 5 Calibration
Stores the upper 8-bit calibration value
for sensor input 5 00h Page 61
B6h R Sensor Input 6 Calibration
Stores the upper 8-bit calibration value
for sensor input 6 00h Page 61
B9h R Sensor Input Calibration
LSB 1
Stores the 2 LSBs of the calibration
value for sensor inputs 1 - 4 00h Page 61
BAh R Sensor Input Calibration
LSB 2
Stores the 2 LSBs of the calibration
value for sensor inputs 5 - 6 00h Page 61
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001623B-page 31
CAP1126
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first
applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics.
Any reads to undefined registers will return 00h. Writes to undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means that the user writes
a logic ‘0’ to it.
6.1 Main Control Register
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is increased, the
effective sensitivity is likewise increased as a smaller delta capacitance is required to generate the same delta count
values. The sensitivity settings may need to be adjusted along with the gain settings such that data overflow does not
occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
Bit 5 - STBY - Enables Standby.
• ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - Capacitive touch sensor input scanning is limited to the sensor inputs set in the Standby Channel register (see
Section 6.20). The status registers will not be cleared until read. LEDs that are linked to capacitive touch sensor
inputs will remain linked and active. Sensor inputs that are no longer sampled will flag a release and then remain
in a non-touched state. LEDs that are manually controlled will be unaffected.
• Bit 4 - DSLEEP - Enables Deep Sleep by deactivating all functions. This bit will be cleared when the WAKE pin is
driven high. ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - All sensor input scanning is disabled. All LEDs are driven to their programmed non-actuated state and no
PWM operations will be done. The status registers are automatically cleared and the INT bit is cleared.
Bit 0 - INT - Indicates that there is an interrupt. When this bit is set, it asserts the ALERT# pin. If a channel detects a
touch and its associated interrupt enable bit is not set to a logic ‘1’, no action is taken.
FDh R Product ID Stores a fixed value that identifies
each product 53h Page 62
FEh R Manufacturer ID Stores a fixed value that identifies
Microchip 5Dh Page 62
FFh R Revision Stores a fixed value that represents
the revision number 83h Page 62
TABLE 6-2: MAIN CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
00h R/W Main Control GAIN[1:0] STBY DSLEEP - - - INT 00h
TABLE 6-3: GAIN BIT DECODE
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
0 0 1
01 2
10 4
11 8
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1126
DS00001623B-page 32 2015 Microchip Technology Inc.
This bit is cleared by writing a logic ‘0’ to it. When this bit is cleared, the ALERT# pin will be deasserted and all status
registers will be cleared if the condition has been removed. If the WAKE/SPI_MOSI pin is asserted as a result of a touch
detected while in Standby, it will likewise be deasserted when this bit is cleared.
Note that the WAKE / SPI_MOSI pin is not driven when communicating via the 4-wire SPI protocol.
• ‘0’ - No interrupt pending.
• ‘1’ - A touch has been detected on one or more channels and the interrupt has been asserted.
6.2 Status Registers
All status bits are cleared when the device enters the Deep Sleep (DSLEEP = ‘1’ - see Section 6.1).
6.2.1 GENERAL STATUS - 02H
Bit 4 - LED - Indicates that one or more LEDs have finished their programmed activity. This bit is set if any bit in the LED
Status register is set.
Bit 3 - RESET - Indicates that the device has come out of reset. This bit is set when the device exits a POR state or
when the RESET pin has been deasserted and qualified via the RESET pin filter (see Section 5.2). This bit will cause
the INT bit to be set and is cleared when the INT bit is cleared.
Bit 2 - MULT - Indicates that the device is blocking detected touches due to the Multiple Touch detection circuitry (see
Section 6.14). This bit will not cause the INT bit to be set and hence will not cause an interrupt.
Bit 1 - MTP - Indicates that the device has detected a number of sensor inputs that exceed the MTP threshold either via
the pattern recognition or via the number of sensor inputs (see Section 6.15). This bit will cause the INT bit to be set if
the MTP_ALERT bit is also set. This bit will not be cleared until the condition that caused it to be set has been removed.
Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status register is set.
6.2.2 SENSOR INPUT STATUS - 03H
The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value of ‘0’ in any bit
indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a touch has been detected.
All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor input is no longer
present. If a touch is still detected, the bits will not be cleared (but this will not cause the interrupt to be asserted - see
Section 6.6).
Bit 5 - CS6 - Indicates that a touch was detected on Sensor Input 6.
Bit 4 - CS5 - Indicates that a touch was detected on Sensor Input 5.
Bit 3 - CS4 - Indicates that a touch was detected on Sensor Input 4.
Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3.
Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2. This sensor input can be linked to LED2.
Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1. This sensor input can be linked to LED1.
6.2.3 LED STATUS - 04H
The LED Status Registers indicate when an LED has completed its configured behavior (see Section 6.31, "LED Behavior
Register") after being actuated by the host (see Section 6.28, "LED Output Control Register"). These bits are ignored
when the LED is linked to a capacitive sensor input. All LED Status bits are cleared when the INT bit is cleared.
Bit 1 - LED2_DN - Indicates that LED2 has finished its behavior after being actuated by the host.
Bit 0 - LED1_DN - Indicates that LED1 has finished its behavior after being actuated by the host.
TABLE 6-4: STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
02h R General Status - - - LED RESET MULT MTP TOUCH 00h
03h R Sensor Input Status
- - CS6 CS5 CS4 CS3 CS2 CS1 00h
04h R LED Status - - - - - - LED2_
DN
LED1_
DN 00h
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CAP1126
6.3 Noise Flag Status Registers
The Noise Flag Status registers store status bits that are generated from the analog block if the detected noise is above
the operating region of the analog detector or the RF noise detector. These bits indicate that the most recently received
data from the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a particular
channel, the delta count value is reset to 00h and thus no touch is detected.
These bits are not sticky and will be cleared automatically if the analog block does not report a noise error.
APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP
threshold (see Section 5.5.4, "Multiple Touch Pattern Detection") even if the corresponding
delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not
counted twice.
APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a
sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,
if RF noise is detected on a sensor input, that sample will be discarded unless the
DIS_RF_NOISE bit is set.
6.4 Sensor Input Delta Count Registers
The Sensor Input Delta Count registers store the delta count that is compared against the threshold used to determine
if a touch has been detected. The count value represents a change in input due to the capacitance associated with a
touch on one of the sensor inputs and is referenced to a calibrated base “Not Touched” count value. The delta is an
instantaneous change and is updated once per sensor input per sensing cycle (see Section 5.5.1, "Sensing Cycle").
The value presented is a standard 2’s complement number. In addition, the value is capped at a value of 7Fh. A reading
of 7Fh indicates that the sensitivity settings are too high and should be adjusted accordingly (see Section 6.5).
The value is also capped at a negative value of 80h for negative delta counts which may result upon a release.
6.5 Sensitivity Control Register
TABLE 6-5: NOISE FLAG STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
0Ah R Noise Flag Status - - CS6_
NOISE
CS5_
NOISE
CS4_
NOISE
CS3_
NOISE
CS2_
NOISE
CS1_
NOISE 00h
TABLE 6-6: SENSOR INPUT DELTA COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
10h R Sensor Input 1
Delta Count Sign 64 32 16 8 4 2 1 00h
11h R Sensor Input 2
Delta Count Sign 64 32 16 8 4 2 1 00h
12h R Sensor Input 3
Delta Count Sign 64 32 16 8 4 2 1 00h
13h R Sensor Input 4
Delta Count Sign 64 32 16 8 4 2 1 00h
14h R Sensor Input 5
Delta Count Sign 64 32 16 8 4 2 1 00h
15h R Sensor Input 6
Delta Count Sign 64 32 16 8 4 2 1 00h
TABLE 6-7: SENSITIVITY CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
1Fh R/W Sensitivity Control - DELTA_SENSE[2:0] BASE_SHIFT[3:0] 2Fh
CAP1126
DS00001623B-page 34 2015 Microchip Technology Inc.
The Sensitivity Control register controls the sensitivity of a touch detection.
Bits 6-4 DELTA_SENSE[2:0] - Controls the sensitivity of a touch detection. The sensitivity settings act to scale the relative
delta count value higher or lower based on the system parameters. A setting of 000b is the most sensitive while a
setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a smaller delta capacitance
corresponding to a “lighter” touch. These settings are more sensitive to noise, however, and a noisy environment may
flag more false touches with higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely, a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
Bits 3 - 0 - BASE_SHIFT[3:0] - Controls the scaling and data presentation of the Base Count registers. The higher the
value of these bits, the larger the range and the lower the resolution of the data presented. The scale factor represents
the multiplier to the bit-weighting presented in these register descriptions.
APPLICATION NOTE: The BASE_SHIFT[3:0] bits normally do not need to be updated. These settings will not affect
touch detection or sensitivity. These bits are sometimes helpful in analyzing the Cap Sensing
board performance and stability.
TABLE 6-8: DELTA_SENSE BIT DECODE
DELTA_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-9: BASE_SHIFT BIT DECODE
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
0 0 0 0 1x
0 0 0 1 2x
0 0 1 0 4x
0 0 1 1 8x
0 1 0 0 16x
0 1 0 1 32x
0 1 1 0 64x
0 1 1 1 128x
1 0 0 0 256x
All others 256x
(default = 1111b)
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CAP1126
6.6 Configuration Registers
The Configuration registers control general global functionality that affects the entire device.
6.6.1 CONFIGURATION - 20H
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
• ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The SMBus interface
will not time out if the clock line is held low. Likewise, it will not reset if both the data and clock lines are held
high for longer than 200us. This is used for I2C compliance.
• ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The SMBus interface
will time out if the clock line is held low for longer than 30ms. Likewise, it will reset if both the data and clock
lines are held high for longer than 200us.
Bit 6 - WAKE_CFG - Configures the operation of the WAKE pin.
• ‘0’ (default) - The WAKE pin is not asserted when a touch is detected while the device is in Standby. It will still be
used to wake the device from Deep Sleep when driven high.
• ‘1’ - The WAKE pin will be asserted high when a touch is detected while the device is in Standby. It will also be
used to wake the device from Deep Sleep when driven high.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 6.19, "Sensor Input Noise Threshold
Register") is used by the device. Setting this bit disables the feature.
• ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does not exceed the
touch threshold, the sample is discarded and not used for the automatic re-calibration routine.
• ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold is used for the
automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the corresponding channel
is set to 0. Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
• ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held indefinitely and no
re-calibration will be performed on any sensor input.
• ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than the MAX_DUR
bit settings, then the re-calibration routine will be restarted (see Section 6.8).
6.6.2 CONFIGURATION 2 - 44H
Bit 7 - INV_LINK_TRAN - Determines the behavior of the Linked LED Transition controls (see Section 6.29).
• ‘0’ (default) - The Linked LED Transition controls set the min duty cycle equal to the max duty cycle.
• ‘1’ - The Linked LED Transition controls will invert the touch signal. For example, a touch signal will be inverted to
a non-touched signal.
Bit 6 - ALT_POL - Determines the ALERT# pin polarity and behavior.
• ‘0’ - The ALERT# pin is active high and push-pull.
• ‘1’ (default) - The ALERT# pin is active low and open drain.
TABLE 6-10: CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
20h R/W Configuration TIMEOUT WAKE_
CFG
DIS_ DIG_
NOISE
DIS_ ANA_
NOISE
MAX_
DUR_EN - --
A0h
(Rev B)
20h
(rev C)
44h R/W Configuration 2 INV_LINK_
TRAN
ALT_
POL
BLK_PWR_
CTRL
BLK_POL_
MIR
SHOW_
RF_
NOISE
DIS_
RF_
NOISE
- INT_
REL_n 40h
CAP1126
DS00001623B-page 36 2015 Microchip Technology Inc.
Bit 5 - BLK_PWR_CTRL - Determines whether the device will reduce power consumption while waiting between conversion
time completion and the end of the polling cycle.
• ‘0’ (default) - The device will always power down as much as possible during the time between the end of the last
conversion and the end of the polling cycle.
• ‘1’ - The device will not power down the Cap Sensor during the time between the end of the last conversion and
the end of the polling cycle.
Bit 4 - BLK_POL_MIR - Determines whether the LED Mirror Control register bits are linked to the LED Polarity bits. Setting
this bit blocks the normal behavior which is to automatically set and clear the LED Mirror Control bits when the LED
Polarity bits are set or cleared.
• ‘0’ (default) - When the LED Polarity controls are set, the corresponding LED Mirror control is automatically set.
Likewise, when the LED Polarity controls are cleared, the corresponding LED Mirror control is also cleared.
• ‘1’ - When the LED Polarity controls are set, the corresponding LED Mirror control is not automatically set.
Bit 3 - SHOW_RF_NOISE - Determines whether the Noise Status bits will show RF Noise as the only input source.
• ‘0’ (default) - The Noise Status registers will show both RF noise and low frequency EMI noise if either is detected
on a capacitive touch sensor input.
• ‘1’ - The Noise Status registers will only show RF noise if it is detected on a capacitive touch sensor input. EMI
noise will still be detected and touches will be blocked normally; however, the status bits will not be updated.
Bit 2 - DIS_RF_NOISE - Determines whether the RF noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If RF noise is detected by the analog block, the delta count on the corresponding channel is set to 0.
Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if RF noise is detected.
Bit 0 - INT_REL_n - Controls the interrupt behavior when a release is detected on a button.
• ‘0’ (default) - An interrupt is generated when a press is detected and again when a release is detected and at the
repeat rate (if enabled - see Section 6.13).
• ‘1’ - An interrupt is generated when a press is detected and at the repeat rate but not when a release is detected.
6.7 Sensor Input Enable Registers
The Sensor Input Enable registers determine whether a capacitive touch sensor input is included in the sampling cycle.
The length of the sampling cycle is not affected by the number of sensor inputs measured.
Bit 5 - CS6_EN - Enables the CS6 input to be included during the sampling cycle.
• ‘0’ - The CS6 input is not included in the sampling cycle.
• ‘1’ (default) - The CS6 input is included in the sampling cycle.
Bit 4 - CS5_EN - Enables the CS5 input to be included during the sampling cycle.
Bit 3 - CS4_EN - Enables the CS4 input to be included during the sampling cycle.
Bit 2 - CS3_EN - Enables the CS3 input to be included during the sampling cycle.
Bit 1 - CS2_EN - Enables the CS2 input to be included during the sampling cycle.
Bit 0 - CS1_EN - Enables the CS1 input to be included during the sampling cycle.
6.8 Sensor Input Configuration Register
TABLE 6-11: SENSOR INPUT ENABLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
21h R/W Sensor Input
Enable - - CS6_EN CS5_EN CS4_EN CS3_EN CS2_EN CS1_EN 3Fh
TABLE 6-12: SENSOR INPUT CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
22h R/W Sensor Input
Configuration MAX_DUR[3:0] RPT_RATE[3:0] A4h
2015 Microchip Technology Inc. DS00001623B-page 37
CAP1126
The Sensor Input Configuration Register controls timings associated with the Capacitive sensor inputs 1 - 6.
Bits 7 - 4 - MAX_DUR[3:0] - (default 1010b) - Determines the maximum time that a sensor pad is allowed to be touched
until the capacitive touch sensor input is recalibrated, as shown in Table 6-13.
Bits 3 - 0 - RPT_RATE[3:0] - (default 0100b) Determines the time duration between interrupt assertions when auto
repeat is enabled. The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-14.
TABLE 6-13: MAX_DUR BIT DECODE
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
0 0 0 0 560ms
0 0 0 1 840ms
0 0 1 0 1120ms
0 0 1 1 1400ms
0 1 0 0 1680ms
0 1 0 1 2240ms
0 1 1 0 2800ms
1 1 1 3360ms
1 0 0 0 3920ms
1 0 0 1 4480ms
1 0 1 0 5600ms (default)
1 0 1 1 6720ms
1 1 0 0 7840ms
1 1 0 1 8906ms
1 1 1 0 10080ms
1 1 1 1 11200ms
TABLE 6-14: RPT_RATE BIT DECODE
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms (default)
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
CAP1126
DS00001623B-page 38 2015 Microchip Technology Inc.
6.9 Sensor Input Configuration 2 Register
Bits 3 - 0 - M_PRESS[3:0] - (default 0111b) - Determines the minimum amount of time that sensor inputs configured to
use auto repeat must detect a sensor pad touch to detect a “press and hold” event. If the sensor input detects a touch
for longer than the M_PRESS[3:0] settings, a “press and hold” event is detected. If a sensor input detects a touch for
less than or equal to the M_PRESS[3:0] settings, a touch event is detected.
The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-16.
6.10 Averaging and Sampling Configuration Register
The Averaging and Sampling Configuration register controls the number of samples taken and the total sensor input
cycle time for all active sensor inputs while the device is functioning in Active state.
Bits 6 - 4 - AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor cycle
as shown in Table 6-18. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
For example, if CS1, CS2, and CS3 are sampled during the sensor cycle, and the AVG[2:0] bits are set to take 4 samples
per channel, then the full sensor cycle will be: CS1, CS1, CS1, CS1, CS2, CS2, CS2, CS2, CS3, CS3, CS3, CS3.
TABLE 6-15: SENSOR INPUT CONFIGURATION 2 REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
23h R/W Sensor Input
Configuration 2 - - - - M_PRESS[3:0] 07h
TABLE 6-16: M_PRESS BIT DECODE
M_PRESS[3:0]
M_PRESS SETTINGS
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms (default)
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-17: AVERAGING AND SAMPLING CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
24h R/W Averaging and
Sampling Config AVG[2:0] SAMP_TIME[1:0] CYCLE_TIME
[1:0] 39h
2015 Microchip Technology Inc. DS00001623B-page 39
CAP1126
Bits 3 - 2 - SAMP_TIME[1:0] - Determines the time to take a single sample as shown in Table 6-19.
Bits 1 - 0 - CYCLE_TIME[1:0] - Determines the overall cycle time for all measured channels during normal operation as
shown in Table 6-20. All measured channels are sampled at the beginning of the cycle time. If additional time is remaining,
then the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The AVG[2:0] bits will take priority so that if more samples
are required than would normally be allowed during the cycle time, the cycle time will be
extended as necessary to accommodate the number of samples to be measured.
6.11 Calibration Activate Register
The Calibration Activate register forces the respective sensor inputs to be re-calibrated affecting both the analog and
digital blocks. During the re-calibration routine, the sensor inputs will not detect a press for up to 600ms and the Sensor
Input Base Count register values will be invalid. During this time, any press on the corresponding sensor pads will invalidate
the re-calibration. When finished, the CALX[9:0] bits will be updated (see Section 6.39).
TABLE 6-18: AVG BIT DECODE
AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-19: SAMP_TIME BIT DECODE
SAMP_TIME[1:0]
Sample Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-20: CYCLE_TIME BIT DECODE
CYCLE_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-21: CALIBRATION ACTIVATE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
26h R/W Calibration
Activate - - CS6_
CAL
CS5_
CAL
CS4_
CAL
CS3_
CAL
CS2_
CAL
CS1_
CAL 00h
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DS00001623B-page 40 2015 Microchip Technology Inc.
When the corresponding bit is set, the device will perform the calibration and the bit will be automatically cleared once
the re-calibration routine has finished.
Bit 5 - CS6_CAL - When set, the CS6 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 4 - CS5_CAL - When set, the CS5 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 3 - CS4_CAL - When set, the CS4 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 2 - CS3_CAL - When set, the CS3 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 1 - CS2_CAL - When set, the CS2 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 0 - CS1_CAL - When set, the CS1 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
6.12 Interrupt Enable Register
The Interrupt Enable register determines whether a sensor pad touch or release (if enabled) causes the interrupt pin to
be asserted.
Bit 5 - CS6_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS6 (associated with the CS6
status bit).
• ‘0’ - The interrupt pin will not be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
• ‘1’ (default) - The interrupt pin will be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
Bit 4 - CS5_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS5 (associated with the CS5
status bit).
Bit 3 - CS4_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS4 (associated with the CS4
status bit).
Bit 2 - CS3_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS3 (associated with the CS3
status bit).
Bit 1 - CS2_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS2 (associated with the CS2
status bit).
Bit 0 - CS1_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS1 (associated with the CS1
status bit).
6.13 Repeat Rate Enable Register
The Repeat Rate Enable register enables the repeat rate of the sensor inputs as described in Section 5.6.1.
Bit 5 - CS6_RPT_EN - Enables the repeat rate for capacitive touch sensor input 6.
• ‘0’ - The repeat rate for CS6 is disabled. It will only generate an interrupt when a touch is detected and when a
release is detected no matter how long the touch is held for.
• ‘1’ (default) - The repeat rate for CS6 is enabled. In the case of a “touch” event, it will generate an interrupt when a
TABLE 6-22: INTERRUPT ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
27h R/W Interrupt
Enable - - CS6_
INT_EN
CS5_
INT_EN
CS4_
INT_EN
CS3_
INT_EN
CS2_
INT_EN
CS1_
INT_EN 3Fh
TABLE 6-23: REPEAT RATE ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
28h R/W Repeat Rate
Enable - - CS6_
RPT_EN
CS5_
RPT_EN
CS4_
RPT_EN
CS3_
RPT_EN
CS2_
RPT_EN
CS1_
RPT_EN 3Fh
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CAP1126
touch is detected and a release is detected (as determined by the INT_REL_n bit - see Section 6.6). In the case of
a “press and hold” event, it will generate an interrupt when a touch is detected and at the repeat rate so long as
the touch is held.
Bit 4 - CS5_RPT_EN - Enables the repeat rate for capacitive touch sensor input 5.
Bit 3 - CS4_RPT_EN - Enables the repeat rate for capacitive touch sensor input 4.
Bit 2 - CS3_RPT_EN - Enables the repeat rate for capacitive touch sensor input 3.
Bit 1 - CS2_RPT_EN - Enables the repeat rate for capacitive touch sensor input 2.
Bit 0 - CS1_RPT_EN - Enables the repeat rate for capacitive touch sensor input 1.
6.14 Multiple Touch Configuration Register
The Multiple Touch Configuration register controls the settings for the multiple touch detection circuitry. These settings
determine the number of simultaneous buttons that may be pressed before additional buttons are blocked and the MULT
status bit is set.
Bit 7 - MULT_BLK_EN - Enables the multiple button blocking circuitry.
• ‘0’ - The multiple touch circuitry is disabled. The device will not block multiple touches.
• ‘1’ (default) - The multiple touch circuitry is enabled. The device will flag the number of touches equal to programmed
multiple touch threshold and block all others. It will remember which sensor inputs are valid and block all
others until that sensor pad has been released. Once a sensor pad has been released, the N detected touches
(determined via the cycle order of CS1 - CS6) will be flagged and all others blocked.
Bits 3 - 2 - B_MULT_T[1:0] - Determines the number of simultaneous touches on all sensor pads before a Multiple Touch
Event is detected and sensor inputs are blocked. The bit decode is given by Table 6-25.
6.15 Multiple Touch Pattern Configuration Register
The Multiple Touch Pattern Configuration register controls the settings for the multiple touch pattern detection circuitry.
This circuitry works like the multiple touch detection circuitry with the following differences:
1. The detection threshold is a percentage of the touch detection threshold as defined by the MTP_TH[1:0] bits
whereas the multiple touch circuitry uses the touch detection threshold.
2. The MTP detection circuitry either will detect a specific pattern of sensor inputs as determined by the Multiple
Touch Pattern register settings or it will use the Multiple Touch Pattern register settings to determine a minimum
number of sensor inputs that will cause the MTP circuitry to flag an event. When using pattern recognition mode,
TABLE 6-24: MULTIPLE TOUCH CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Ah R/W Multiple Touch
Config
MULT_
BLK_
EN
- - - B_MULT_T[1:0] - - 80h
TABLE 6-25: B_MULT_T BIT DECODE
B_MULT_T[1:0]
Number of Simultaneous Touches
1 0
0 0 1 (default)
01 2
10 3
11 4
TABLE 6-26: MULTIPLE TOUCH PATTERN CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Bh R/W Multiple Touch
Pattern Config MTP_ EN - - MTP_TH[1:0] COMP_
PTRN
MTP_
ALERT 00h
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DS00001623B-page 42 2015 Microchip Technology Inc.
if all of the sensor inputs set by the Multiple Touch Pattern register have a delta count greater than the MTP
threshold or have their corresponding Noise Flag Status bits set, the MTP bit will be set. When using the absolute
number mode, if the number of sensor inputs with thresholds above the MTP threshold or with Noise Flag Status
bits set is equal to or greater than this number, the MTP bit will be set.
3. When an MTP event occurs, all touches are blocked and an interrupt is generated.
4. All sensor inputs will remain blocked so long as the requisite number of sensor inputs are above the MTP threshold
or have Noise Flag Status bits set. Once this condition is removed, touch detection will be restored. Note that
the MTP status bit is only cleared by writing a ‘0’ to the INT bit once the condition has been removed.
Bit 7 - MTP_EN - Enables the multiple touch pattern detection circuitry.
• ‘0’ (default) - The MTP detection circuitry is disabled.
• ‘1’ - The MTP detection circuitry is enabled.
Bits 3-2 - MTP_TH[1:0] - Determine the MTP threshold, as shown in Table 6-27. This threshold is a percentage of sensor
input threshold (see Section 6.18, "Sensor Input Threshold Registers") when the device is in the Fully Active state or of
the standby threshold (see Section 6.23, "Standby Threshold Register") when the device is in the Standby state.
Bit 1 - COMP_PTRN - Determines whether the MTP detection circuitry will use the Multiple Touch Pattern register as a
specific pattern of sensor inputs or as an absolute number of sensor inputs.
• ‘0’ (default) - The MTP detection circuitry will use the Multiple Touch Pattern register bit settings as an absolute
minimum number of sensor inputs that must be above the threshold or have Noise Flag Status bits set. The number
will be equal to the number of bits set in the register.
• ‘1’ - The MTP detection circuitry will use pattern recognition. Each bit set in the Multiple Touch Pattern register
indicates a specific sensor input that must have a delta count greater than the MTP threshold or have a Noise Flag
Status bit set. If the criteria are met, the MTP status bit will be set.
Bit 0 - MTP_ALERT - Enables an interrupt if an MTP event occurs. In either condition, the MTP status bit will be set.
• ‘0’ (default) - If an MTP event occurs, the ALERT# pin is not asserted.
• ‘1’ - If an MTP event occurs, the ALERT# pin will be asserted.
6.16 Multiple Touch Pattern Register
The Multiple Touch Pattern register acts as a pattern to identify an expected sensor input profile for diagnostics or other
significant events. There are two methods for how the Multiple Touch Pattern register is used: as specific sensor inputs
or number of sensor input that must exceed the MTP threshold or have Noise Flag Status bits set. Which method is used
is based on the COMP_PTRN bit (see Section 6.15). The methods are described below.
1. Specific Sensor Inputs: If, during a single polling cycle, the specific sensor inputs above the MTP threshold or
with Noise Flag Status bits set match those bits set in the Multiple Touch Pattern register, an MTP event is
flagged.
2. Number of Sensor Inputs: If, during a single polling cycle, the number of sensor inputs with a delta count above
the MTP threshold or with Noise Flag Status bits set is equal to or greater than the number of pattern bits set, an
MTP event is flagged.
TABLE 6-27: MTP_TH BIT DECODE
MTP_TH[1:0]
Threshold Divide Setting
1 0
0 0 12.5% (default)
0 1 25%
1 0 37.5%
1 1 100%
TABLE 6-28: MULTIPLE TOUCH PATTERN REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Dh R/W Multiple
Touch Pattern - - CS6_
PTRN
CS5_
PTRN
CS4_
PTRN
CS3_
PTRN
CS2_
PTRN
CS1_
PTRN 3Fh
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CAP1126
Bit 5 - CS6_PTRN - Determines whether CS6 is considered as part of the Multiple Touch Pattern.
• ‘0’ - CS6 is not considered a part of the pattern.
• ‘1’ - CS6 is considered a part of the pattern or the absolute number of sensor inputs that must have a delta count
greater than the MTP threshold or have the Noise Flag Status bit set is increased by 1.
Bit 4 - CS5_PTRN - Determines whether CS5 is considered as part of the Multiple Touch Pattern.
Bit 3 - CS4_PTRN - Determines whether CS4 is considered as part of the Multiple Touch Pattern.
Bit 2 - CS3_PTRN - Determines whether CS3 is considered as part of the Multiple Touch Pattern.
Bit 1 - CS2_PTRN - Determines whether CS2 is considered as part of the Multiple Touch Pattern.
Bit 0 - CS1_PTRN - Determines whether CS1 is considered as part of the Multiple Touch Pattern.
6.17 Recalibration Configuration Register
The Recalibration Configuration register controls the automatic re-calibration routine settings as well as advanced controls
to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor Input 1 Threshold
register.
• ‘0’ - Each Sensor Input X Threshold register is updated individually.
• ‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor Input Threshold
registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input Threshold 6). The individual Sensor
Input X Threshold registers (Sensor Input 2 Threshold through Sensor Input 6 Threshold) can be individually
updated at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise status bit is set.
• ‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
• ‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if the noise status bit
is set.
• ‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
• ‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to trigger a digital recalibration
as shown in Table 6-30.
TABLE 6-29: RECALIBRATION CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Fh R/W Recalibration
Configuration
BUT_
LD_TH
NO_
CLR_
INTD
NO_
CLR_
NEG
NEG_DELTA_
CNT[1:0] CAL_CFG[2:0] 8Ah
TABLE 6-30: NEG_DELTA_CNT BIT DECODE
NEG_DELTA_CNT[1:0]
Number of Consecutive Negative Delta Count Values
1 0
00 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
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DS00001623B-page 44 2015 Microchip Technology Inc.
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-calibration routine.
The settings apply to all sensor inputs universally (though individual sensor inputs can be configured to support re-calibration
- see Section 6.11).
Note 6-1 Recalibration Samples refers to the number of samples that are measured and averaged before the
Base Count is updated however does not control the base count update period.
Note 6-2 Update Time refers to the amount of time (in polling cycle periods) that elapses before the Base
Count is updated. The time will depend upon the number of channels active, the averaging setting,
and the programmed cycle time.
6.18 Sensor Input Threshold Registers
The Sensor Input Threshold registers store the delta threshold that is used to determine if a touch has been detected.
When a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with
a touch. If the sensor input change exceeds the threshold settings, a touch is detected.
When the BUT_LD_TH bit is set (see Section 6.17 - bit 7), writing data to the Sensor Input 1 Threshold register will
update all of the sensor input threshold registers (31h - 35h inclusive).
6.19 Sensor Input Noise Threshold Register
TABLE 6-31: CAL_CFG BIT DECODE
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
0 0 0 16 16
0 0 1 32 32
0 1 0 64 64 (default)
0 1 1 128 128
1 0 0 256 256
1 0 1 256 1024
1 1 0 256 2048
1 1 1 256 4096
TABLE 6-32: SENSOR INPUT THRESHOLD REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
30h R/W Sensor Input 1
Threshold - 64 32 16 8 4 2 1 40h
31h R/W Sensor Input 2
Threshold - 64 32 16 8 4 2 1 40h
32h R/W Sensor Input 3
Threshold - 64 32 16 8 4 2 1 40h
33h R/W Sensor Input 4
Threshold - 64 32 16 8 4 2 1 40h
34h R/W Sensor Input 5
Threshold - 64 32 16 8 4 2 1 40h
35h R/W Sensor Input 6
Threshold - 64 32 16 8 4 2 1 40h
TABLE 6-33: SENSOR INPUT NOISE THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
38h R/W Sensor Input
Noise Threshold CS_BN_TH [1:0] 01h
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CAP1126
The Sensor Input Noise Threshold register controls the value of a secondary internal threshold to detect noise and
improve the automatic recalibration routine. If a capacitive touch sensor input exceeds the Sensor Input Noise Threshold
but does not exceed the sensor input threshold, it is determined to be caused by a noise spike. That sample is not used
by the automatic re-calibration routine. This feature can be disabled by setting the DIS_DIG_NOISE bit.
Bits 1-0 - CS1_BN_TH[1:0] - Controls the noise threshold for all capacitive touch sensor inputs, as shown in Table 6-34.
The threshold is proportional to the threshold setting.
6.20 Standby Channel Register
The Standby Channel register controls which (if any) capacitive touch sensor inputs are active during Standby.
Bit 5 - CS6_STBY - Controls whether the CS6 channel is active in Standby.
• ‘0’ (default) - The CS6 channel not be sampled during Standby mode.
• ‘1’ - The CS6 channel will be sampled during Standby Mode. It will use the Standby threshold setting, and the
standby averaging and sensitivity settings.
Bit 4 - CS5_STBY - Controls whether the CS5 channel is active in Standby.
Bit 3 - CS4_STBY - Controls whether the CS4 channel is active in Standby.
Bit 2 - CS3_STBY - Controls whether the CS3 channel is active in Standby.
Bit 1 - CS2_STBY - Controls whether the CS2 channel is active in Standby.
Bit 0 - CS1_STBY - Controls whether the CS1 channel is active in Standby.
6.21 Standby Configuration Register
The Standby Configuration register controls averaging and cycle time for those sensor inputs that are active in Standby.
This register is useful for detecting proximity on a small number of sensor inputs as it allows the user to change averaging
and sample times on a limited number of sensor inputs and still maintain normal functionality in the fully active
state.
Bit 7 - AVG_SUM - Determines whether the active sensor inputs will average the programmed number of samples or
whether they will accumulate for the programmed number of samples.
• ‘0’ - (default) - The active sensor input delta count values will be based on the average of the programmed number
of samples when compared against the threshold.
• ‘1’ - The active sensor input delta count values will be based on the summation of the programmed number of
samples when compared against the threshold. This bit should only be set when performing proximity detection as
TABLE 6-34: CSX_BN_TH BIT DECODE
CS_BN_TH[1:0]
Percent Threshold Setting
1 0
0 0 25%
0 1 37.5% (default)
1 0 50%
1 1 62.5%
TABLE 6-35: STANDBY CHANNEL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
40h R/W Standby Channel - - CS6_
STBY
CS5_
STBY
CS4_
STBY
CS3_
STBY
CS2_
STBY
CS1_
STBY 00h
TABLE 6-36: STANDBY CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
41h R/W Standby Configuration
AVG_
SUM STBY_AVG[2:0] STBY_SAMP_
TIME[1:0]
STBY_CY_TIME
[1:0] 39h
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DS00001623B-page 46 2015 Microchip Technology Inc.
a physical touch will overflow the delta count registers and may result in false readings.
Bits 6 - 4 - STBY_AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor
cycle as shown in Table 6-37. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
Bit 3-2 - STBY SAMP_TIME[1:0] - Determines the time to take a single sample when the device is in Standby as shown
in Table 6-38.
Bits 1 - 0 - STBY_CY_TIME[2:0] - Determines the overall cycle time for all measured channels during standby operation
as shown in Table 6-39. All measured channels are sampled at the beginning of the cycle time. If additional time is
remaining, the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The STBY_AVG[2:0] bits will take priority so that if more
samples are required than would normally be allowed during the cycle time, the cycle time
will be extended as necessary to accommodate the number of samples to be measured.
TABLE 6-37: STBY_AVG BIT DECODE
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-38: STBY_SAMP_TIME BIT DECODE
STBY_SAMP_TIME[1:0]
Sampling Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-39: STBY_CY_TIME BIT DECODE
STBY_CY_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
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CAP1126
6.22 Standby Sensitivity Register
The Standby Sensitivity register controls the sensitivity for sensor inputs that are active in Standby.
Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensor inputs that are active in Standby. The sensitivity settings
act to scale the relative delta count value higher or lower based on the system parameters. A setting of 000b is the
most sensitive while a setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a
smaller delta C corresponding to a “lighter” touch. These settings are more sensitive to noise however and a noisy environment
may flag more false touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
6.23 Standby Threshold Register
The Standby Threshold register stores the delta threshold that is used to determine if a touch has been detected. When
a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with a
touch. If the sensor input change exceeds the threshold settings, a touch is detected.
6.24 Sensor Input Base Count Registers
TABLE 6-40: STANDBY SENSITIVITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
42h R/W Standby Sensitivity
- - - - - STBY_SENSE[2:0] 02h
TABLE 6-41: STBY_SENSE BIT DECODE
STBY_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-42: STANDBY THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
43h R/W Standby Threshold
- 64 32 16 8 4 2 1 40h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
50h R Sensor Input 1
Base Count 128 64 32 16 8 4 2 1 C8h
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DS00001623B-page 48 2015 Microchip Technology Inc.
The Sensor Input Base Count registers store the calibrated “Not Touched” input value from the capacitive touch sensor
inputs. These registers are periodically updated by the re-calibration routine.
The routine uses an internal adder to add the current count value for each reading to the sum of the previous readings
until sample size has been reached. At this point, the upper 16 bits are taken and used as the Sensor Input Base Count.
The internal adder is then reset and the re-calibration routine continues.
The data presented is determined by the BASE_SHIFT[3:0] bits (see Section 6.5).
6.25 LED Output Type Register
The LED Output Type register controls the type of output for the LED pins. Each pin is controlled by a single bit. Refer
to application note 21.4 CAP1126Family LED Configuration Options for more information about implementing LEDs.
Bit 1 - LED2_OT - Determines the output type of the LED2 pin.
• ‘0’ (default) - The LED2 pin is an open-drain output with an external pull-up resistor. When the appropriate pin is
set to the “active” state (logic ‘1’), the pin will be driven low. Conversely, when the pin is set to the “inactive” state
(logic ‘0’), then the pin will be left in a High Z state and pulled high via an external pull-up resistor.
• ‘1’ - The LED2 pin is a push-pull output. When driving a logic ‘1’, the pin is driven high. When driving a logic ‘0’, the
pin is driven low.
Bit 0 - LED1_OT - Determines the output type of the LED1 pin.
6.26 Sensor Input LED Linking Register
The Sensor Input LED Linking register controls whether a capacitive touch sensor input is linked to an LED output. If
the corresponding bit is set, then the appropriate LED output will change states defined by the LED Behavior controls
(see Section 6.31) in response to the capacitive touch sensor input.
Bit 1 - CS2_LED2 - Links the LED2 output to a detected touch on the CS2 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
• ‘0’ (default) - The LED 2 output is not associated with the CS2 input. If a touch is detected on the CS2 input, the
LED will not automatically be actuated. The LED is enabled and controlled via the LED Output Control register
(see Section 6.28) and the LED Behavior registers (see Section 6.31).
51h R Sensor Input 2
Base Count 128 64 32 16 8 4 2 1 C8h
52h R Sensor Input 3
Base Count 128 64 32 16 8 4 2 1 C8h
53h R Sensor Input 4
Base Count 128 64 32 16 8 4 2 1 C8h
54h R Sensor Input 5
Base Count 128 64 32 16 8 4 2 1 C8h
55h R Sensor Input 6
Base Count 128 64 32 16 8 4 2 1 C8h
TABLE 6-44: LED OUTPUT TYPE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
71h R/W LED Output
Type ----- - LED2_
OT
LED1_
OT 00h
TABLE 6-45: SENSOR INPUT LED LINKING REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
72h R/W Sensor Input
LED Linking
- - - - - - CS2_
LED2
CS1_
LED1
00h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS (CONTINUED)
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2015 Microchip Technology Inc. DS00001623B-page 49
CAP1126
• ‘1’ - The LED 2 output is associated with the CS2 input. If a touch is detected on the CS2 input, the LED will be
actuated and behave as defined in Table 6-52.
Bit 0 - CS1_LED1 - Links the LED1 output to a detected touch on the CS1 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
6.27 LED Polarity Register
The LED Polarity register controls the logical polarity of the LED outputs. When these bits are set or cleared, the corresponding
LED Mirror controls are also set or cleared (unless the BLK_POL_MIR bit is set - see Section 6.6, "Configuration
Registers"). Table 6-48, "LED Polarity Behavior" shows the interaction between the polarity controls, output
controls, and relative brightness.
APPLICATION NOTE: The polarity controls determine the final LED pin drive. A touch on a linked capacitive touch
sensor input is treated in the same way as the LED Output Control bit being set to a logic ‘1’.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’ then the LED will be on and that the CAP1126 LED pin is sinking the LED current.
Conversely, if the LED pin is driven to a logic ‘1’, the LED will be off and there is no current
flow. See Figure 5-1, "System Diagram for CAP1126".
APPLICATION NOTE: This application note applies when the LED polarity is inverted (LEDx_POL = ‘0’). For LED
operation, the duty cycle settings determine the % of time that the LED pin will be driven to
a logic ‘0’ state in. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven low (i.e. maximum % of time that the LED is on) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven low (i.e. minimum
% of time that the LED is on). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at the minimum duty cycle setting.
Breathe operations will ramp the duty cycle from the minimum duty cycle to the maximum
duty cycle.
APPLICATION NOTE: This application note applies when the LED polarity is non-inverted (LEDx_POL = ‘1’). For
LED operation, the duty cycle settings determine the % of time that the LED pin will be driven
to a logic ‘1’ state. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven high (i.e. maximum % of time that the LED is off) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven high (i.e. minimum
% of time that the LED is off). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at 100 minus the minimum duty
cycle setting. Breathe operations will ramp the duty cycle from 100 minus the minimum duty
cycle to 100 minus the maximum duty cycle.
APPLICATION NOTE: The LED Mirror controls (see Section 6.30, "LED Mirror Control Register") work with the
polarity controls with respect to LED brightness but will not have a direct effect on the output
pin drive.
Bit 1 - LED2_POL - Determines the polarity of the LED2 output.
• ‘0’ (default) - The LED2 output is inverted. For example, a setting of ‘1’ in the LED Output Control register will
cause the LED pin output to be driven to a logic ‘0’.
• ‘1’ - The LED2 output is non-inverted. For example, a setting of ‘1’ in the LED Output Control register will cause
the LED pin output to be driven to a logic ‘1’ or left in the high-z state as determined by its output type.
Bit 0 - LED1_POL - Determines the polarity of the LED1 output.
TABLE 6-46: LED POLARITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
73h R/W LED Polarity - - - - - - LED2_
POL
LED1_
POL 00h
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DS00001623B-page 50 2015 Microchip Technology Inc.
6.28 LED Output Control Register
The LED Output Control Register controls the output state of the LED pins that are not linked to sensor inputs.
The LED Polarity Control Register will determine the non actuated state of the LED pins. The actuated LED behavior is
determined by the LED behavior controls (see Section 6.31, "LED Behavior Register").
Table 6-48 shows the interaction between the polarity controls, output controls, and relative brightness.
Bit 1 - LED2_DR - Determines whether LED2 output is driven high or low.
• ‘0’ (default) - The LED2 output is driven at the minimum duty cycle or not actuated.
• ‘1’ - The LED2 output is High Z or driven at the maximum duty cycle or actuated.
Bit 0 - LED1_DR - Determines whether LED1 output is driven high or low.
TABLE 6-47: LED OUTPUT CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
74h R/W LED Output
Control --- - -- LED2_
DR
LED1_
DR 00h
Note: If an LED is linked to a sensor input in the Sensor Input LED Linking Register (Section 6.26, "Sensor Input
LED Linking Register"), the corresponding bit in the LED Output Control Register is ignored (i.e. a linked
LED cannot be host controlled).
TABLE 6-48: LED POLARITY BEHAVIOR
LED Output
Control
Register or
Touch
Polarity Max Duty Min Duty Brightness LED Appearance
0 inverted (‘0’) not used
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
min duty cycle
on at min duty
cycle
1 inverted (‘0’)
maximum % of time
that the LED is on
(logic 0)
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
max duty cycle. Brightness
ramps from min
duty cycle to max duty
cycle
according to LED
behavior
0 non-inverted
(‘1’) not used
minimum % of time
that the LED is off
(logic 1)
maximum brightness at
100 minus min duty
cycle.
on at 100 - min
duty cycle
1 non-inverted
(‘1’)
maximum % of time
that the LED is off
(logic 1)
minimum % of time
that the LED is off
(logic 1)
For Direct behavior,
maximum brightness is
100 minus max duty
cycle. When breathing,
max brightness is
100 minus min duty
cycle. Brightness
ramps from 100 - min
duty cycle to 100 - max
duty cycle.
according to LED
behavior
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CAP1126
6.29 Linked LED Transition Control Register
The Linked LED Transition Control register controls the LED drive when the LED is linked to a capacitive touch sensor
input. These controls work in conjunction with the INV_LINK_TRAN bit (see Section 6.6.2, "Configuration 2 - 44h") to
create smooth transitions from host control to linked LEDs.
Bit 1 - LED2_LTRAN - Determines the transition effect when LED2 is linked to CS2.
• ‘0’ (default) - When the LED output control bit for LED2 is ‘1’, and then LED2 is linked to CS2 and no touch is
detected, the LED will change states.
• ‘1’ - If the INV_LINK_TRAN bit is ‘1’, when the LED output control bit for CS2 is ‘1’, and then CS2 is linked to LED2
and no touch is detected, the LED will not change states. In addition, the LED state will change when the sensor
pad is touched. If the INV_LINK_TRAN bit is ‘0’, when the LED output control bit for CS2 is ‘1’, and then CS2 is
linked to LED2 and no touch is detected, the LED will not change states. However, the LED state will not change
when the sensor pad is touched.
APPLICATION NOTE: If the LED behavior is not “Direct” and the INV_LINK_TRAN bit it ‘0’, the LED will not perform
as expected when the LED2_LTRAN bit is set to ‘1’. Therefore, if breathe and pulse
behaviors are used, set the INV_LINK_TRAN bit to ‘1’.
Bit 0 - LED1_LTRAN - Determines the transition effect when LED1 is linked to CS1.
6.30 LED Mirror Control Register
The LED Mirror Control Registers determine the meaning of duty cycle settings when polarity is non-inverted for each
LED channel. When the polarity bit is set to ‘1’ (non-inverted), to obtain correct steps for LED ramping, pulse, and
breathe behaviors, the min and max duty cycles need to be relative to 100%, rather than the default, which is relative
to 0%.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’, the LED will be on and the CAP1126 LED pin is sinking the LED current. When
the polarity bit is set to ‘1’, it is considered non-inverted. For systems using the opposite LED
configuration, mirror controls would apply when the polarity bit is ‘0’.
These bits are changed automatically if the corresponding LED Polarity bit is changed (unless the BLK_POL_MIR bit is
set - see Section 6.6).
Bit 1 - LED2_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
• ‘0’ (default) - The duty cycle settings are determined relative to 0% and are determined directly with the settings.
• ‘1’ - The duty cycle settings are determined relative to 100%.
Bit 0 - LED1_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
6.31 LED Behavior Register
TABLE 6-49: LINKED LED TRANSITION CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
77h R/W Linked LED Transition
Control - ----- LED2_
LTRAN
LED1_
LTRAN 00h
TABLE 6-50: LED MIRROR CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
79h R/W LED Mirror Control
------
LED2_
MIR _
EN
LED1_
MIR _
EN
00h
TABLE 6-51: LED BEHAVIOR REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
81h R/W LED Behavior 1 - - - - LED2_CTL[1:0] LED1_CTL[1:0] 00h
CAP1126
DS00001623B-page 52 2015 Microchip Technology Inc.
The LED Behavior register controls the operation of LEDs. Each LED pin is controlled by a 2-bit field and the behavior
is determined by whether the LED is linked to a capacitive touch sensor input or not.
If the corresponding LED output is linked to a capacitive touch sensor input, the appropriate behavior will be enabled /
disabled based on touches and releases.
If the LED output is not associated with a capacitive touch sensor input, the appropriate behavior will be enabled / disabled
by the LED Output Control register. If the respective LEDx_DR bit is set to a logic ‘1’, this will be associated as a
“touch”, and if the LEDx_DR bit is set to a logic ‘0’, this will be associated as a “release”.
Table 6-52, "LEDx_CTL Bit Decode" shows the behavior triggers. The defined behavior will activate when the Start Trigger
is met and will stop when the Stop Trigger is met. Note the behavior of the Breathe Hold and Pulse Release option.
The LED Polarity Control register will determine the non actuated state of the LED outputs (see Section 6.27, "LED
Polarity Register").
APPLICATION NOTE: If an LED is not linked to a capacitive touch sensor input and is breathing (via the Breathe
or Pulse behaviors), it must be unactuated and then re-actuated before changes to behavior
are processed. For example, if the LED output is breathing and the Maximum duty cycle is
changed, this change will not take effect until the LED output control register is set to ‘0’ and
then re-set to ‘1’.
APPLICATION NOTE: If an LED is not linked to the capacitive touch sensor input and configured to operate using
Pulse 1 Behavior, then the circuitry will only be actuated when the corresponding output
control bit is set. It will not check the bit condition until the Pulse 1 behavior is finished. The
device will not remember if the bit was cleared and reset while it was actuated.
APPLICATION NOTE: If an LED is actuated and not linked and the desired LED behavior is changed, this new
behavior will take effect immediately; however, the first instance of the changed behavior
may act incorrectly (e.g. if changed from Direct to Pulse 1, the LED output may ‘breathe’ 4
times and then end at minimum duty cycle). LED Behaviors will operate normally once the
LED has been un-actuated and then re-actuated.
APPLICATION NOTE: If an LED is actuated and it is switched from linked to a capacitive touch sensor input to
unlinked (or vice versa), the LED will respond to the new command source immediately if
the behavior was Direct or Breathe. For Pulse behaviors, it will complete the behavior
already in progress. For example, if a linked LED was actuated by a touch and the control
is changed so that it is unlinked, it will check the status of the corresponding LED Output
Control bit. If that bit is ‘0’, then the LED will behave as if a release was detected. Likewise,
if an unlinked LED was actuated by the LED Output Control register and the control is
changed so that it is linked and no touch is detected, then the LED will behave as if a release
was detected.
Bits 3 - 2 - LED2_CTL[1:0] - Determines the behavior of LED2 as shown in Table 6-52.
Bits 1 - 0 - LED1_CTL[1:0] - Determines the behavior of LED1 as shown in Table 6-52.
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CAP1126
APPLICATION NOTE: The PWM frequency is determined based on the selected LED behavior, the programmed
breathe period, and the programmed min and max duty cycles. For the Direct behavior
mode, the PWM frequency is calculated based on the programmed Rise and Fall times. If
these are set at 0, then the maximum PWM frequency will be used based on the
programmed duty cycle settings.
6.32 LED Pulse 1 Period Register
The LED Pulse Period 1 register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 01b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms (24 x 32ms = 768ms). The total range is from 32ms to 4.064 seconds as shown in Table 6-54 with the
default being 1024ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
Bit 7 - ST_TRIG - Determines the start trigger for the LED Pulse behavior.
• ‘0’ (default) - The LED will Pulse when a touch is detected or the drive bit is set.
• ‘1’ - The LED will Pulse when a release is detected or the drive bit is cleared.
TABLE 6-52: LEDX_CTL BIT DECODE
LEDx_CTL
[1:0] Operation Description Start TRigger Stop Trigger
1 0
0 0 Direct The LED is driven to the programmed state
(active or inactive). See Figure 6-7
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
0 1 Pulse 1
The LED will “Pulse” a programmed number
of times. During each “Pulse” the LED will
breathe up to the maximum brightness and
back down to the minimum brightness so that
the total “Pulse” period matches the programmed
value.
Touch or Release
Detected or LED
Output Control bit
set or cleared
(see Section 6.32)
n/a
1 0 Pulse 2
The LED will “Pulse” when the start trigger is
detected. When the stop trigger is detected, it
will “Pulse” a programmable number of times
then return to its minimum brightness.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
1 1 Breathe
The LED will breathe. It will be driven with a
duty cycle that ramps up from the programmed
minimum duty cycle (default 0%) to
the programmed maximum duty cycle duty
cycle (default 100%) and then back down.
Each ramp takes up 50% of the programmed
period. The total period of each “breath” is
determined by the LED Breathe Period controls
- see Section 6.34.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
TABLE 6-53: LED PULSE 1 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
84h R/W LED Pulse 1
Period
ST_
TRIG
P1_
PER6
P1_
PER5
P1_
PER4
P1_
PER3
P1_
PER2
P1_
PER1
P1_
PER0 20h
CAP1126
DS00001623B-page 54 2015 Microchip Technology Inc.
The Pulse 1 operation is shown in Figure 6-1 when the LED output is configured for non-inverted polarity (LEDx_POL
= 1) and in Figure 6-2 for inverted polarity (LEDx_POL = 0).
.
FIGURE 6-1: Pulse 1 Behavior with Non-Inverted Polarity
FIGURE 6-2: Pulse 1 Behavior with Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
00h 0 32
01h 1 32
02h 2 64
03h 3 96
. . . . . . . . .
7Dh 125 4000
Normal – untouched
operation Normal – untouched
operation
Touch Detected or
Release Detected
(100% - Pulse 1 Max Duty Cycle) * Brightness
X pulses after touch or after release
Pulse 1 Period
(P1_PER)
(100% - Pulse 1 Min Duty Cycle) * Brightness
LED
Brightness
Normal – untouched
operation
Normal – untouched
operation
Touch Detected or
Release Detected
Pulse 1 Min Duty Cycle * Brightness
X pulses after touch or after release
Pulse Period
(P1_PER)
Pulse 1 Max Duty Cycle * Brightness
LED
Brightness
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6.33 LED Pulse 2 Period Register
The LED Pulse 2 Period register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 10b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 640ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
The Pulse 2 Behavior is shown in Figure 6-3 for non-inverted polarity (LEDx_POL = 1) and in Figure 6-4 for inverted
polarity (LEDx_POL = 0).
7Eh 126 4032
7Fh 127 4064
TABLE 6-55: LED PULSE 2 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
85h R/W LED Pulse 2
Period - P2_
PER6
P2_
PER5
P2_
PER4
P2_
PER3
P2_
PER2
P2_
PER1
P2_
PER0 14h
FIGURE 6-3: Pulse 2 Behavior with Non-Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE (CONTINUED)
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
. . .
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
(100% - Pulse 2 Min Duty Cycle) *
Brightness
(100% - Pulse 2 Max Duty Cycle) * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness
CAP1126
DS00001623B-page 56 2015 Microchip Technology Inc.
6.34 LED Breathe Period Register
The LED Breathe Period register determines the overall period of a breathe operation as determined by the LED_CTL
registers (see Table 6-52 - setting 11b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 2976ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
6.35 LED Configuration Register
The LED Configuration register controls general LED behavior as well as the number of pulses that are sent for the
PULSE LED output behavior.
Bit 6 - RAMP_ALERT - Determines whether the device will assert the ALERT# pin when LEDs actuated by the LED
Output Control register bits have finished their respective behaviors. Interrupts will only be generated if the LED activity
is generated by writing the LED Output Control registers. Any LED activity associated with touch detection will not cause
an interrupt to be generated when the LED behavior has been finished.
• ‘0’ (default) - The ALERT# pin will not be asserted when LEDs actuated by the LED Output Control register have
finished their programmed behaviors.
• ‘1’ - The ALERT# pin will be asserted whenever any LED that is actuated by the LED Output Control register has
finished its programmed behavior.
Bits 5 - 3 - PULSE2_CNT[2:0] - Determines the number of pulses used for the Pulse 2 behavior as shown in Table 6-58.
Bits 2 - 0 - PULSE1_CNT[2:0] - Determines the number of pulses used for the Pulse 1 behavior as shown in Table 6-58.
FIGURE 6-4: Pulse 2 Behavior with Inverted Polarity
TABLE 6-56: LED BREATHE PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
86h R/W LED Breathe
Period - BR_
PER6
BR_
PER5
BR_
PER4
BR_
PER3
BR_
PER2
BR_
PER1
BR_
PER0 5Dh
TABLE 6-57: LED CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
88h R/W LED Config - RAMP_
ALERT PULSE2_CNT[2:0] PULSE1_CNT[2:0] 04h
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
Pulse 2 Max Duty Cycle * Brightness
Pulse 2 Min Duty Cycle * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness . . .
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CAP1126
6.36 LED Duty Cycle Registers
The LED Duty Cycle registers determine the minimum and maximum duty cycle settings used for the LED for each LED
behavior. These settings affect the brightness of the LED when it is fully off and fully on.
The LED driver duty cycle will ramp up from the minimum duty cycle to the maximum duty cycle and back down again.
APPLICATION NOTE: When operating in Direct behavior mode, changes to the Duty Cycle settings will be applied
immediately. When operating in Breathe, Pulse 1, or Pulse 2 modes, the LED must be
unactuated and then re-actuated before changes to behavior are processed.
Bits 7 - 4 - X_MAX_DUTY[3:0] - Determines the maximum PWM duty cycle for the LED drivers as shown in Table 6-60.
Bits 3 - 0 - X_MIN_DUTY[3:0] - Determines the minimum PWM duty cycle for the LED drivers as shown in Table 6-60.
TABLE 6-58: PULSEX_CNT DECODE
PULSEX_CNT[2:0]
Number of Breaths
21 0
0 0 0 1 (default - Pulse 2)
00 1 2
01 0 3
01 1 4
1 0 0 5 (default - Pulse 1)
10 1 6
11 0 7
11 1 8
TABLE 6-59: LED DUTY CYCLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
90h R/W LED Pulse 1 Duty
Cycle P1_MAX_DUTY[3:0] P1_MIN_DUTY[3:0] F0h
91h R/W LED Pulse 2 Duty
Cycle P2_MAX_DUTY[3:0] P2_MIN_DUTY[3:0] F0h
92h R/W LED Breathe
Duty Cycle BR_MAX_DUTY[3:0] BR_MIN_DUTY[3:0] F0h
93h R/W Direct Duty Cycle DR_MAX_DUTY[3:0] DR_MIN_DUTY[3:0] F0h
TABLE 6-60: LED DUTY CYCLE DECODE
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
0 0 0 0 7% 0%
0 0 0 1 9% 7%
0 0 1 0 11% 9%
0 0 1 1 14% 11%
0 1 0 0 17% 14%
0 1 0 1 20% 17%
0 1 1 0 23% 20%
0 1 1 1 26% 23%
1 0 0 0 30% 26%
1 0 0 1 35% 30%
1 0 1 0 40% 35%
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DS00001623B-page 58 2015 Microchip Technology Inc.
6.37 LED Direct Ramp Rates Register
The LED Direct Ramp Rates register control the rising and falling edge time of an LED that is configured to operate in
Direct behavior mode. The rising edge time corresponds to the amount of time the LED takes to transition from its minimum
duty cycle to its maximum duty cycle. Conversely, the falling edge time corresponds to the amount of time that
the LED takes to transition from its maximum duty cycle to its minimum duty cycle.
Bits 5 - 3 - RISE_RATE[2:0] - Determines the rising edge time of an LED when it transitions from its minimum drive state
to its maximum drive state as shown in Table 6-62.
Bits 2 - 0 - FALL_RATE[2:0] - Determines the falling edge time of an LED when it transitions from its maximum drive
state to its minimum drive state as shown in Table 6-62.
6.38 LED Off Delay Register
The LED Off Delay register determines the amount of time that an LED remains at its maximum duty cycle (or minimum
as determined by the polarity controls) before it starts to ramp down. If the LED is operating in Breathe mode, this delay
is applied at the top of each “breath”. If the LED is operating in the Direct mode, this delay is applied when the LED is
unactuated.
1 0 1 1 46% 40%
1 1 0 0 53% 46%
1 1 0 1 63% 53%
1 1 1 0 77% 63%
1 1 1 1 100% 77%
TABLE 6-61: LED DIRECT RAMP RATES REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
94h R/W LED Direct Ramp
Rates - - RISE_RATE[2:0] FALL_RATE[2:0] 00h
TABLE 6-62: RISE / FALL RATE DECODE
RISE_RATE/ FALL_RATE/ Bit Decode
Rise / Fall Time (TRISE / TFALL)
21 0
00 0 0
0 0 1 250ms
0 1 0 500ms
0 1 1 750ms
1 0 0 1s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2s
TABLE 6-63: LED OFF DELAY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
95h R/W LED Off Delay
Register - BR_OFF_DLY[2:0] DIR_OFF_DLY[3:0] 00h
TABLE 6-60: LED DUTY CYCLE DECODE (CONTINUED)
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
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Bits 6 - 4 - BR_OFF_DLY[2:0] - Determines the Breathe behavior mode off delay, which is the amount of time an LED
in Breathe behavior mode remains inactive after it finishes a breathe pulse (ramp on and ramp off), as shown in Figure 6-
5 (non-inverted polarity LEDx_POL = 1) and Figure 6-6 (inverted polarity LEDx_POL = 0). Available settings are shown
in Table 6-64.
FIGURE 6-5: Breathe Behavior with Non-Inverted Polarity
FIGURE 6-6: Breathe Behavior with Inverted Polarity
LED Actuated
100% - Breathe Max Min Cycle * Brightness
100% - Breathe Min Duty Cycle *
Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
LED Actuated
Breathe Max Duty Cycle * Brightness
Breathe Min Duty Cycle * Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
CAP1126
DS00001623B-page 60 2015 Microchip Technology Inc.
Bits 3 - 0 - DIR_OFF_DLY[3:0] - Determines the turn-off delay, as shown in Table 6-65, for all LEDs that are configured
to operate in Direct behavior mode.
The Direct behavior operation is determined by the combination of programmed Rise Time, Fall Time, Min and Max Duty
cycles, Off Delay, and polarity. Figure 6-7 shows the behavior for non-inverted polarity (LEDx_POL = 1) while Figure 6-
8 shows the behavior for inverted polarity (LEDx_POL = 0).
TABLE 6-64: BREATHE OFF DELAY SETTINGS
BR_OFF_DLY [2:0]
OFF Delay
2 10
0 0 0 0 (default)
0 0 1 0.25s
0 1 0 0.5s
0 1 1 0.75s
1 0 0 1.0s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2.0s
FIGURE 6-7: Direct Behavior for Non-Inverted Polarity
FIGURE 6-8: Direct Behavior for Inverted Polarity
Normal –
untouched
operation
RISE_RATE
Setting (tRISE)
(100% - Max Duty
Cycle) * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
(100% - Min Duty Cycle) *
Brightness LED
Brightness
Normal –
untouched
operation RISE_RATE
Setting (tRISE)
Min Duty Cycle * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
Max Duty Cycle * Brightness
LED
Brightness
2015 Microchip Technology Inc. DS00001623B-page 61
CAP1126
6.39 Sensor Input Calibration Registers
The Sensor Input Calibration registers hold the 10-bit value that represents the last calibration value.
TABLE 6-65: OFF DELAY DECODE
OFF Delay[3:0] Bit Decode
OFF Delay (tOFF_DLY)
32 1 0
00 0 0 0
0 0 0 1 250ms
0 0 1 0 500ms
0 0 1 1 750ms
0 1 0 0 1s
0 1 0 1 1.25s
0 1 1 0 1.5s
0 1 1 1 2s
1 0 0 0 2.5s
1 0 0 1 3.0s
1 0 1 0 3.5s
1 0 1 1 4.0s
1 1 0 0 4.5s
All others 5.0s
TABLE 6-66: SENSOR INPUT CALIBRATION REGISTERS
ADDR Register R/W B7 B6 B5 B4 B3 B2 B1 B0 Default
B1h Sensor Input 1
Calibration R CAL1_9 CAL1_8 CAL1_7 CAL1_6 CAL1_5 CAL1_4 CAL1_3 CAL1_2 00h
B2h Sensor Input 2
Calibration R CAL2_9 CAL2_8 CAL2_7 CAL2_6 CAL2_5 CAL2_4 CAL2_3 CAL2_2 00h
B3h Sensor Input 3
Calibration R CAL3_9 CAL3_8 CAL3_7 CAL3_6 CAL3_5 CAL3_4 CAL3_3 CAL3_2 00h
B4h Sensor Input 4
Calibration R CAL4_9 CAL4_8 CAL4_7 CAL4_6 CAL4_5 CAL4_4 CAL4_3 CAL4_2 00h
B5h Sensor Input 5
Calibration R CAL5_9 CAL5_8 CAL5_7 CAL5_6 CAL5_5 CAL5_4 CAL5_3 CAL5_2 00h
B6h Sensor Input 6
Calibration R CAL6_9 CAL6_8 CAL6_7 CAL6_6 CAL6_5 CAL6_4 CAL6_3 CAL6_2 00h
B9h
Sensor Input
Calibration LSB
1
R CAL4_1 CAL4_0 CAL3_1 CAL3_0 CAL2_1 CAL2_0 CAL1_1 CAL1_0 00h
BAh
Sensor Input
Calibration LSB
2
R - - - - CAL6_1 CAL6_0 CAL5_1 CAL5_0 00h
CAP1126
DS00001623B-page 62 2015 Microchip Technology Inc.
6.40 Product ID Register
The Product ID register stores a unique 8-bit value that identifies the device.
6.41 Manufacturer ID Register
The Vendor ID register stores an 8-bit value that represents Microchip.
6.42 Revision Register
The Revision register stores an 8-bit value that represents the part revision.
TABLE 6-67: PRODUCT ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FDh R Product ID 0 1 0 1 0 0 1 1 53h
TABLE 6-68: VENDOR ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FEh R Manufacturer ID 0 1 0 1 1 1 0 1 5Dh
TABLE 6-69: REVISION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FFh R Revision 1 0 0 0 0 0 1 1 83h
2015 Microchip Technology Inc. DS00001623B-page 63
CAP1126
7.0 PACKAGE INFORMATION
7.1 CAP1126 Package Drawings
Note: For the most current package drawings, see the Microchip Packaging Specification at:
http://www.microchip.com/packaging.
FIGURE 7-1: 16-Pin QFN 4mm x 4mm Package Drawing
CAP1126
DS00001623B-page 64 2015 Microchip Technology Inc.
FIGURE 7-2: 16-Pin QFN 4mm x 4mm Package Dimensions
FIGURE 7-3: 16-Pin QFN 4mm x 4mm PCB Footprint
2015 Microchip Technology Inc. DS00001623B-page 65
CAP1126
7.2 Package Marking
FIGURE 7-4: CAP1126 Package Markings
C 1 26 - 1
Y WWN N N A
RCC
e3
TOP
BOTTOM
Bottom marking not allowed
PB-FREE/GREEN SYMBOL
(Matte Sn)
Lines 1-3:
Line 4:
Center Horizontal Alignment
Left Horizontal Alignment
PIN 1
0.41
3x 0.56
Line 1 – SMSC Logo without circled R symbol
Line 2 – Device ID, Version
Line 3 – Year, Week, Alphanumeric Traceability Code
Line 4 – Revision, Country Code
1
CAP1126
DS00001623B-page 66 2015 Microchip Technology Inc.
APPENDIX A: DEVICE DELTA
A.1 Delta from CAP1026 to CAP1126
1. Updated circuitry to improve power supply rejection.
2. Updated LED driver duty cycle decode values to have more distribution at lower values - closer to a logarithmic
curve. See Table 6-60, "LED Duty Cycle Decode".
3. Updated bug that breathe periods were not correct above 2.6s. This includes rise / fall time decodes above 1.5s.
4. Added filtering on RESET pin to prevent errant resets.
5. Updated controls so that the RESET pin assertion places the device into the lowest power state available and
causes an interrupt when released. See Section 5.2, "RESET Pin".
6. Added 1 bit to the LED Off Delay register (see Section 6.38, "LED Off Delay Register") to extend times from 2s
to 5s in 0.5s intervals.
7. Breathe behavior modified. A breathe off delay control was added to the LED Off Delay Register (see Section
6.38, "LED Off Delay Register") so the LEDs can be configured to remain inactive between breathes.
8. Added controls for the LED transition effects when linking LEDs to capacitive sensor inputs. See Section 6.29,
"Linked LED Transition Control Register".
9. Added controls to “mirror” the LED duty cycle outputs so that when polarity changes, the LED brightness levels
look right. These bits are automatically set when polarity is set. Added control to break this auto-set behavior.
See Section 6.30, "LED Mirror Control Register".
10. Added Multiple Touch Pattern detection circuitry. See Section 6.15, "Multiple Touch Pattern Configuration Register".
11. Added General Status register to flag Multiple touches, Multiple Touch Pattern issues and general touch detections.
See Section 6.2, "Status Registers".
12. Added bits 6 and 5 to the Recalibration Configuration register (2Fh - see Section 6.17, "Recalibration Configuration
Register"). These bits control whether the accumulation of intermediate data and the consecutive negative
delta counts counter are cleared when the noise status bit is set.
13. Added Configuration 2 register for LED linking controls, noise detection controls, and control to interrupt on press
but not on release. Added control to change alert pin polarity. See Section 6.6, "Configuration Registers".
14. Updated Deep Sleep behavior so that device does not clear DSLEEP bit on received communications but will
wake to communicate.
15. Changed PWM frequency for LED drivers. The PWM frequency was derived from the programmed breathe
period and duty cycle settings and it ranged from ~4Hz to ~8000 Hz. The PWM frequency has been updated to
be a fixed value of ~2000Hz.
16. Register delta:
Table A.1 Register Delta From CAP1026 to CAP1126
Address Register Delta Delta Default
00h
Page 31
Changed - Main Status /
Control
added bits 7-6 to control gain 00h
02h
Page 32
New - General Status new register to store MTP, MULT, LED,
RESET, and general TOUCH bits
00h
44h
Page 35
New - Configuration 2 new register to control alert polarity, LED
touch linking behavior, LED output behavior,
and noise detection, and interrupt on
release
40h
24h
Page 38
Changed - Averaging
Control
updated register bits - moved
SAMP_AVG[2:0] bits and added SAMP_-
TIME bit 1. Default changed
39h
2Bh
Page 41
New - Multiple Touch
Pattern Configuration
new register for Multiple Touch Pattern
configuration - enable and threshold settings
80h
2015 Microchip Technology Inc. DS00001623B-page 67
CAP1126
2Dh
Page 42
New - Multiple Touch
Pattern Register
new register for Multiple Touch Pattern
detection circuitry - pattern or number of
sensor inputs
3Fh
2Fh
Page 43
Changed - Recalibration
Configuration
updated register - updated CAL_CFG bit
decode to add a 128 averages setting and
removed highest time setting. Default
changed. Added bit 6 NO_CLR_INTD and
bit 5 NO_CLR_NEG.
8Ah
38h
Page 44
Changed - Sensor Input
Noise Threshold
updated register bits - removed bits 7 - 3
and consolidated all controls into bits 1 - 0.
These bits will set the noise threshold for
all channels. Default changed
01h
39h Removed - Noise
Threshold Register 2
removed register n/a
41h
Page 45
Changed - Standby Configuration
updated register bits - moved
STBY_AVG[2:0] bits and added STBY_-
TIME bit 1. Default changed
39h
77h
Page 51
New - Linked LED Transition
Control
new register to control transition effect
when LED linked to sensor inputs
00h
79h
Page 51
New - LED Mirror Control new register to control LED output mirroring
for brightness control when polarity
changed
00h
90h
Page 57
Changed - LED Pulse 1
Duty Cycle
changed bit decode to be more logarithmic F0h
91h
Page 57
Changed - LED Pulse 2
Duty Cycle
changed bit decode to be more logarithmic F0h
92h
Page 57
Changed - LED Breathe
Duty Cycle
changed bit decode to be more logarithmic F0h
93h
Page 57
Changed - LED Direct
Duty Cycle
changed bit decode to be more logarithmic F0h
95h Added controls - LED Off
Delay
Added bits 6-4 BR_OFF_DLY[2:0]
Added bit 3 DIR_OFF_DLY[3]
00h
FDh
Page 62
Changed - Product ID Changed bit decode for CAP1126 53h
Table A.1 Register Delta From CAP1026 to CAP1126 (continued)
Address Register Delta Delta Default
CAP1126
DS00001623B-page 68 2015 Microchip Technology Inc.
APPENDIX B: DATA SHEET REVISION HISTORY
Revision Section/Figure/Entry Correction
DS00001623B (02-09-15)
Features, Table 2-1, Table 2-
2, "Pin Types", Section 5.0,
"General Description"
References to BC-Link Interface, BC_DATA, BC_-
CLK, BC-IRQ#, BC-Link bus have been removed
Application Note under Table
2-6
[BC-Link] hidden in data sheet
Table 3-2, "Electrical Specifications"
BC-Link Timing Section hidden in data sheet
Table 4-1 Protocol Used for 68K Pull Down Resistor changed
from “BC-Link Communications” to “Reserved”
Section 4.2.2, "SMBus
Address and RD / WR Bit"
Replaced “client address” with “slave address” in this
section.
Section 4.2.4, SMBus ACK
and NACK Bits, Section 4.2.5,
SMBus Stop Bit,Section 4.2.7,
SMBus and I2C Compatibility
Replaced “client” with “slave” in these sections.
Table 4-4, "Read Byte Protocol"
Heading changed from “Client Address” to “Slave
Address”
Table 6-1 Register Name for Register Address 77h changed
from “LED Linked Transition Control” to “Linked LED
Transition Control”
Section 6.30 changed CS2 to LED2
Section 7.7 Package Marking Updated package drawing
Appendix A: Device Delta changed 2Dh to 2Fh in item #12
Product Identification System Removed BC-Link references
REV A REV A replaces previous SMSC version Rev. 1.32 (01-05-12)
Rev. 1.32 (01-05-12) Table 3-2, "Electrical Specifications"
Added conditions for tHD:DAT.
Section 4.2.7, "SMBus and
I2C Compatibility"
Renamed from “SMBus and I2C Compliance.”
First paragraph, added last sentence: “For information
on using the CAP1188 in an I2C system, refer to
SMSC AN 14.0 SMSC Dedicated Slave Devices in
I
2C Systems.”
Added: CAP1188 supports I2C fast mode at 400kHz.
This covers the SMBus max time of 100kHz.
Section 6.4, "Sensor Input
Delta Count Registers"
Changed negative value cap from FFh to 80h.
Rev. 1.31 (08-18-11) Section 4.3.3, "SMBus Send
Byte"
Added an application note: The Send Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit is
set).
Section 4.3.4, "SMBus
Receive Byte"
Added an application note: The Receive Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit
is set).
Rev. 1.3 (05-18-11) Section 6.42, "Revision Register"
Updated revision ID from 82h to 83h.
Rev. 1.2 (02-10-11) Section A.8, "Delta from Rev
B (Mask B0) to Rev C (Mask
B1)"
Added.
Cover Corrected block diagram. ALERT#/BC_IRQ# is an
output, not an input.
2015 Microchip Technology Inc. DS00001623B-page 69
CAP1126
Table 2-1, "Pin Description for
CAP1126"
Changed value in “Unused Connection” column for
the ADDR_COMM pin from “Connect to Ground” to
“n/a“.
Table 3-2, "Electrical Specifications"
PSR improvements made in functional revision B.
Changed PSR spec from ±100 typ and ±200 max
counts / V to ±3 and ±10 counts / V. Conditions
updated.
Section 5.5.2, "Recalibrating
Sensor Inputs"
Added more detail with subheadings for each type of
recalibration.
Section 6.6, "Configuration
Registers"
Added bit 5 BLK_PWR_CTRL to the Configuration 2
Register 44h.
The TIMEOUT bit is set to ‘1’ by default for functional
revision B and is set to ‘0’ by default for functional
revision C.
Section 6.42, "Revision Register"
Updated revision ID in register FFh from 81h to 82h.
Rev. 1.1 (11-17-10) Document Updated for functional revision B. See Section A.7,
"Delta from Rev A (Mask A0) to Rev B (Mask B0)".
Cover Added to General Description: “includes circuitry and
support for enhanced sensor proximity detection.”
Added the following Features:
Calibrates for Parasitic Capacitance
Analog Filtering for System Noise Sources
Press and Hold feature for Volume-like Applications
Table 3-2, "Electrical Specifications"
Conditions for Power Supply Rejection modified adding
the following:
Sampling time = 2.56ms
Averaging = 1
Negative Delta Counts = Disabled
All other parameters default
Section 6.11, "Calibration Activate
Register"
Updated register description to indicate which re-calibration
routine is used.
Section 6.14, "Multiple Touch
Configuration Register"
Updated register description to indicate what will
happen.
Table 6-34, "CSx_BN_TH Bit
Decode"
Table heading changed from “Threshold Divide Setting”
to “Percent Threshold Setting”.
Rev. 1.0 (06-14-10) Initial release
Revision Section/Figure/Entry Correction
CAP1126
DS00001623B-page 70 2015 Microchip Technology Inc.
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Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains
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To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification”
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CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
• Local Sales Office
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Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://www.microchip.com/support
2015 Microchip Technology Inc. DS00001623B-page 71
CAP1126
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. [X] - 1 - XXX - [X](1)
l l l l
Device Temperature Package Tape and Reel
Range Option
Example:
Note 1: Tape and Reel identifier only appears in the catalog part number description. This identifier is used for ordering
purposes and is not printed on the device package. Check with your Microchip Sales Office for package availability
with the Tape and Reel option.
Device: CAP1126
Temperature
Range:
Blank = 0°C to +85°C (Extended Commercial)
Package: AP = QFN
Tape and
Reel Option:
TR = Tape and Reel(1)
CAP1126-1-AP-TR
16-pin QFN 4mm x 4mm (RoHS compliant)
Six capacitive touch sensor inputs, Two
LED drivers, Dedicated Wake, Reset,
SMBus / BC-Link / SPI interfaces
Reel size is 4,000 pieces
CAP1126
DS00001623B-page 72 2015 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device applications and the like is provided only for your convenience and may be
superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO
REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR
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or otherwise, under any Microchip intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC, FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer, LANCheck,
MediaLB, MOST, MOST logo, MPLAB, OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC, SST, SST Logo, SuperFlash and
UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are registered trademarks of Microchip Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit Serial
Programming, ICSP, Inter-Chip Connectivity, KleerNet, KleerNet logo, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK,
MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, RightTouch logo, REAL ICE, SQI, Serial
Quad I/O, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.
Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.
GestIC is a registered trademarks of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in
other countries.
All other trademarks mentioned herein are property of their respective companies.
© 2015, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
ISBN: 9781632770332
Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
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analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
2015 Microchip Technology Inc. DS00001623B-page 73
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2015 Microchip Technology Inc. DS00001622B-page 1
General Description
The CAP1128, which incorporates RightTouch® technology,
is a multiple channel Capacitive Touch sensor
with multiple power LED drivers. It contains eight (8)
individual capacitive touch sensor inputs with programmable
sensitivity for use in touch sensor applications.
Each sensor input automatically recalibrates to compensate
for gradual environmental changes.
The CAP1128 also contains two (2) LED drivers that
offer full-on / off, variable rate blinking, dimness controls,
and breathing. Each of the LED drivers may be
linked to one of the sensor inputs to be actuated when
a touch is detected. As well, each LED driver may be
individually controlled via a host controller.
The CAP1128 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons
to be touched simultaneously. If this pattern is
detected, then a status bit is set and an interrupt generated.
Additionally, the CAP1128 includes circuitry and support
for enhanced sensor proximity detection.
The CAP1128 offers multiple power states operating at
low quiescent currents. In the Standby state of operation,
one or more capacitive touch sensor inputs are
active and all LEDs may be used. If a touch is detected,
it will wake the system using the WAKE/SPI_MOSI pin.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor
inputs are active. Driving the WAKE/SPI_MOSI pin or
communications will wake the device.
Applications
• Desktop and Notebook PCs
• LCD Monitors
• Consumer Electronics
• Appliances
Features
• Eight (8) Capacitive Touch Sensor Inputs
- Programmable sensitivity
- Automatic recalibration
- Individual thresholds for each button
• Proximity Detection
• Multiple Button Pattern Detection
• Calibrates for Parasitic Capacitance
• Analog Filtering for System Noise Sources
• Press and Hold feature for Volume-like Applications
• Multiple Communication Interfaces
- SMBus / I2C compliant interface
- SPI communications
- Pin selectable communications protocol and
multiple slave addresses (SMBus / I2C only)
• Low Power Operation
- 5uA quiescent current in Deep Sleep
- 50uA quiescent current in Standby (1 sensor
input monitored)
- Samples one or more channels in Standby
• Two (2) LED Driver Outputs
- Open Drain or Push-Pull
- Programmable blink, breathe, and dimness
controls
- Can be linked to Capacitive Touch Sensor
inputs
• Dedicated Wake output flags touches in low
power state
• System RESET pin
• Available in 20-pin 4mm x 4mm QFN RoHS compliant
package
CAP1128
8 Channel Capacitive Touch Sensor with 2 LED Drivers
CAP1128
DS00001622B-page 2 2015 Microchip Technology Inc.
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The last character of the literature number is the version number, (e.g., DS30000000A is version A of document DS30000000).
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An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
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To determine if an errata sheet exists for a particular device, please check with one of the following:
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When contacting a sales office, please specify which device, revision of silicon and data sheet (include -literature number) you are
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2015 Microchip Technology Inc. DS00001622B-page 3
CAP1128
Table of Contents
1.0 Block Diagram ................................................................................................................................................................................. 4
2.0 Pin Description ................................................................................................................................................................................ 5
3.0 Electrical Specifications .................................................................................................................................................................. 9
4.0 Communications ........................................................................................................................................................................... 12
5.0 General Description ...................................................................................................................................................................... 23
6.0 Register Description ...................................................................................................................................................................... 29
7.0 Package Information ..................................................................................................................................................................... 67
Appendix A: Device Delta ................................................................................................................................................................... 72
Appendix B: Data Sheet Revision History ........................................................................................................................................... 74
The Microchip Web Site ...................................................................................................................................................................... 76
Customer Change Notification Service ............................................................................................................................................... 76
Customer Support ............................................................................................................................................................................... 76
Product Identification System ............................................................................................................................................................. 77
CAP1128
DS00001622B-page 4 2015 Microchip Technology Inc.
1.0 BLOCK DIAGRAM
SMBus /
BC-Link /
SPI Slave
Protocol
SMCLK/ BC_CLK /
SPI_CLK
SMDATA / BC_DATA/ SPI_MSIO /
SPI_MISO
VDD GND
ALERT# / BC_IRQ#
Capacitive Touch Sensing Algorithm
LED1
CS1 CS2 CS3 CS4 CS5 CS6
LED Driver, Breathe,
and Dimness control
WAKE / SPI_MOSI
CS7 CS8
RESET
ADDR_COMM
SPI_CS#
LED2
2015 Microchip Technology Inc. DS00001622B-page 5
CAP1128
2.0 PIN DESCRIPTION
FIGURE 2-1: CAP1128 Pin Diagram (20-Pin QFN)
TABLE 2-1: PIN DESCRIPTION FOR CAP1128
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
1 SPI_CS# Active low chip-select for SPI bus DI (5V) Connect to
Ground
2 WAKE / SPI_-
MOSI
WAKE - Active high wake / interrupt output
Standby power state - requires pull-down resistor DO
Pull-down
WAKE - Active high wake input - requires pull-down Resistor
resistor
Deep Sleep power state
DI
SPI_MOSI - SPI Master-Out-Slave-In port when used in
normal mode DI (5V) Connect to
Ground
1
2
3
4
15
14
13
12
20
19
18
17
6
7
8
9
GND
ALERT# / BC_IRQ#
WAKE / SPI_MOSI
SPI_CS#
SMCLK / BC_CLK / SPI_CLK
SMDAT / BC_DATA / SPI_MSIO /
SPI_MISO CS7 RESET
CS5
CS6
5
10
11
16
VDD
CS1
CS2
CS4
CS8
CS3
N/C*
LED1
LED2
ADDR_COMM
CAP1128
20 pin QFN
N/C*
*N/C pins must be connected to ground
CAP1128
DS00001622B-page 6 2015 Microchip Technology Inc.
3
SMDATA /
SPI_MSIO /
SPI_MISO
SMDATA - Bi-directional, open-drain SMBus data -
requires pull-up resistor DIOD (5V)
n/a
SPI_MSIO - SPI Master-Slave-In-Out bidirectional port
when used in bi-directional mode DIO
SPI_MISO - SPI Master-In-Slave-Out port when used in
normal mode DO
4 SMCLK / SPI_-
CLK
SMCLK - SMBus clock input - requires pull-up resistor DI (5V)
SPI_CLK - SPI clock input DI (5V) n/a
5 N/C Not Internally Connected n/a Connect to
Ground
6 LED1
Open drain LED 1 driver (default) OD (5V) Connect to
Ground
Push-pull LED 1 driver DO
leave open or
connect to
Ground
7 LED2
Open drain LED 2 driver (default) OD (5V) Connect to
Ground
Push-pull LED 2 driver DO
leave open or
connect to
Ground
8 N/C Not Internally Connected n/a Connect to
Ground
9 RESET Active high soft reset for system - resets all registers to
default values. If not used, connect to ground. DI (5V) Connect to
Ground
10 ALERT#
ALERT# - Active low alert / interrupt output for SMBus
alert or SPI interrupt OD (5V) Connect to
Ground
ALERT# - Active high push-pull alert / interrupt output
for SMBus alert or SPI interrupt DO leave open
11 ADDR_COMM Address / communications select pin - pull-down resistor
determines address / communications mechanism AI n/a
12 CS8 Capacitive Touch Sensor Input 8 AIO Connect to
Ground
13 CS7 Capacitive Touch Sensor Input 7 AIO Connect to
Ground
14 CS6 Capacitive Touch Sensor Input 6 AIO Connect to
Ground
15 CS5 Capacitive Touch Sensor Input 5 AIO Connect to
Ground
16 CS4 Capacitive Touch Sensor Input 4 AIO Connect to
Ground
TABLE 2-1: PIN DESCRIPTION FOR CAP1128 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
2015 Microchip Technology Inc. DS00001622B-page 7
CAP1128
APPLICATION NOTE: When the ALERT# pinis configured as an active low output, it will be open drain. When it is
configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1128 is unpowered.
APPLICATION NOTE: The SPI_CS# pin should be grounded when SMBus, or I2C,communications are used.
The pin types are described in Table 2-2. All pins labeled with (5V) are 5V tolerant.
17 CS3 Capacitive Touch Sensor Input 3 AIO Connect to
Ground
18 CS2 Capacitive Touch Sensor Input 2 AIO Connect to
Ground
19 CS1 Capacitive Touch Sensor Input 1 AIO Connect to
Ground
20 VDD Positive Power supply Power n/a
Bottom Pad GND Ground Power n/a
TABLE 2-2: PIN TYPES
Pin Type Description
Power This pin is used to supply power or ground to the device.
DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
AIO Analog Input / Output -This pin is used as an I/O for analog signals.
DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output,
it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a
pull-up resistor. This pin is 5V tolerant.
DO Push-pull Digital Output - This pin is used as a digital output and can sink and source current.
DIO Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
TABLE 2-1: PIN DESCRIPTION FOR CAP1128 (CONTINUED)
Pin
Number Pin Name Pin Function Pin Type Unused
Connection
CAP1128
DS00001622B-page 8 2015 Microchip Technology Inc.
3.0 ELECTRICAL SPECIFICATIONS
Note 3-1 Stresses above those listed could cause permanent damage to the device. This is a stress rating
only and functional operation of the device at any other condition above those indicated in the
operation sections of this specification is not implied.
Note 3-2 For the 5V tolerant pins that have a pull-up resistor, the voltage difference between V5VT_PIN and VDD
must never exceed 3.6V.
Note 3-3 The Package Power Dissipation specification assumes a recommended thermal via design consisting
of a 3x3 matrix of 0.3mm (12mil) vias at 1.0mm pitch connected to the ground plane with a 2.5 x
2.5mm thermal landing.
Note 3-4 Junction to Ambient (θJA) is dependent on the design of the thermal vias. Without thermal vias and
a thermal landing, the θJA is approximately 60°C/W including localized PCB temperature increase.
TABLE 3-1: ABSOLUTE MAXIMUM RATINGS
Voltage on 5V tolerant pins (V5VT_PIN) -0.3 to 5.5 V
Voltage on 5V tolerant pins (|V5VT_PIN - VDD|) Note 3-2 0 to 3.6 V
Voltage on VDD pin -0.3 to 4 V
Voltage on any other pin to GND -0.3 to VDD + 0.3 V
Package Power Dissipation up to TA = 85°C for 20 pin QFN
(see Note 3-3)
0.9 W
Junction to Ambient (θJA) (see Note 3-4) 58 °C/W
Operating Ambient Temperature Range -40 to 125 °C
Storage Temperature Range -55 to 150 °C
ESD Rating, All Pins, HBM 8000 V
2015 Microchip Technology Inc. DS00001622B-page 9
CAP1128
TABLE 3-2: ELECTRICAL SPECIFICATIONS
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
DC Power
Supply Voltage VDD 3.0 3.3 3.6 V
Supply Current
ISTBY 120 170 uA
Standby state active
1 sensor input monitored
No LEDs active
Default conditions (8 avg, 70ms
cycle time)
ISTBY 50 uA
Standby state active
1 sensor input monitored
No LEDs active
1 avg, 140ms cycle time,
IDSLEEP 5 15 uA
Deep Sleep state active
LEDs at 100% or 0% Duty Cycle
No communications
TA < 40°C
3.135 < VDD < 3.465V
IDD 500 600 uA Capacitive Sensing Active
No LEDs active
Capacitive Touch Sensor Inputs
Maximum Base
Capacitance CBASE 50 pF Pad untouched
Minimum Detectable
Capacitive Shift ΔCTOUCH 20 fF
Pad touched - default conditions (1
avg, 35ms cycle time, 1x sensitivity)
Recommended Cap
Shift ΔCTOUCH 0.1 2 pF Pad touched - Not tested
Power Supply Rejection
PSR ±3 ±10 counts /
V
Untouched Current Counts
Base Capacitance 5pF - 50pF
Maximum sensitivity
Negative Delta Counts disabled
All other parameters default
Timing
RESET Pin Delay tRST_DLY 10 ms
Time to communications
ready tCOMM_DLY 15 ms
Time to first conversion
ready tCONV_DLY 170 200 ms
LED Drivers
Duty Cycle DUTYLED 0 100 % Programmable
Drive Frequency fLED 2 kHz
Sinking Current ISINK 24 mA VOL = 0.4
Sourcing Current ISOURCE 24 mA VOH = VDD - 0.4
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
I/O Pins
Output Low Voltage VOL 0.4 V ISINK_IO = 8mA
Output High Voltage VOH VDD - 0.4 V ISOURCE_IO = 8mA
CAP1128
DS00001622B-page 10 2015 Microchip Technology Inc.
Note 3-5 The ALERT pin will not glitch high or low at power up if connected to VDD or another voltage.
Note 3-6 The SMCLK and SMDATA pins will not glitch low at power up if connected to VDD or another voltage.
Input High Voltage VIH 2.0 V
Input Low Voltage VIL 0.8 V
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
RESET Pin Release
to conversion ready tRESET 170 200 ms
SMBus Timing
Input Capacitance CIN 5 pF
Clock Frequency fSMB 10 400 kHz
Spike Suppression tSP 50 ns
Bus Free Time Stop to
Start tBUF 1.3 us
Start Setup Time tSU:STA 0.6 us
Start Hold Time tHD:STA 0.6 us
Stop Setup Time tSU:STO 0.6 us
Data Hold Time tHD:DAT 0 us When transmitting to the master
Data Hold Time tHD:DAT 0.3 us When receiving from the master
Data Setup Time tSU:DAT 0.6 us
Clock Low Period tLOW 1.3 us
Clock High Period tHIGH 0.6 us
Clock / Data Fall Time tFALL 300 ns Min = 20+0.1CLOAD ns
Clock / Data Rise
Time tRISE 300 ns Min = 20+0.1CLOAD ns
Capacitive Load CLOAD 400 pF per bus line
SPI Timing
Clock Period tP 250 ns
Clock Low Period tLOW 0.4 x tP 0.6 x tP ns
Clock High Period tHIGH 0.4 x tP 0.6 x tP ns
Clock Rise / Fall time tRISE / tFALL 0.1 x tP ns
Data Output Delay tD:CLK 10 ns
Data Setup Time tSU:DAT 20 ns
Data Hold Time tHD:DAT 20 ns
SPI_CS# to SPI_CLK
setup time tSU:CS 0 ns
Wake Time tWAKE 10 20 us SPI_CS# asserted to CLK assert
TABLE 3-2: ELECTRICAL SPECIFICATIONS (CONTINUED)
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
2015 Microchip Technology Inc. DS00001622B-page 11
CAP1128
4.0 COMMUNICATIONS
4.1 Communications
The CAP1128communicates using the 2-wire SMBus or I2C bus, the 2-wire proprietary BC-Link, or the SPI bus. If the
proprietary BC-Link protocol is required for your application, please contact your Microchip representative for ordering
instructions. Regardless of communication mechanism, the device functionality remains unchanged. The communications
mechanism as well as the SMBus (or I2C) slave address is determined by the resistor connected between the
ADDR_COMM pin and ground as shown in Table 4-1.
4.1.1 SMBUS (I2C) COMMUNICATIONS
When configured to communicate via the SMBus, the CAP1128 supports the following protocols: Send Byte, Receive
Byte, Read Byte, Write Byte, Read Block, and Write Block. In addition, the device supports I2C formatting for block read
and block write protocols.
APPLICATION NOTE: For SMBus/I2C communications, the SPI_CS# pin is not used and should be grounded; any
data presented to this pin will be ignored.
See Section 4.2 and Section 4.3 for more information on the SMBus bus and protocols respectively.
4.1.2 SPI COMMUNICATIONS
When configured to communicate via the SPI bus, the CAP1128supports both bi-directional 3-wire and normal 4-wire
protocols and uses the SPI_CS# pin to enable communications.
APPLICATION NOTE: See Section 4.5 and Section 4.6 for more information on the SPI bus and protocols
respectively.Upon power up, the CAP1128 will not respond to any communications for up to
15ms. After this time, full functionality is available.
4.2 System Management Bus
The CAP1128 communicates with a host controller, such as an SIO, through the SMBus. The SMBus is a two-wire serial
communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in
Figure 4-1. Stretching of the SMCLK signal is supported; however, the CAP1128 will not stretch the clock signal.
TABLE 4-1: ADDR_COMM PIN DECODE
Pull-Down Resistor (+/- 5%) Protocol Used SMBus Address
GND SPI Communications using Normal
4-wire Protocol Used
n/a
56k SPI Communications using BiDirectional
3-wire Protocol Used
n/a
68k Reserved n/a
82k SMBus / I2C 0101_100(r/w)
100k SMBus / I2C 0101_011(r/w)
120k SMBus / I2C 0101_010(r/w)
150k SMBus / I2C 0101_001(r/w)
VDD SMBus / I2C 0101_000(r/w)
CAP1128
DS00001622B-page 12 2015 Microchip Technology Inc.
4.2.1 SMBUS START BIT
The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the
SMBus Clock line is in a logic ‘1’ state.
4.2.2 SMBUS ADDRESS AND RD / WR BIT
The SMBus Address Byte consists of the 7-bit slave address followed by the RD / WR indicator bit. If this RD / WR bit
is a logic ‘0’, then the SMBus Host is writing data to the slave device. If this RD / WR bit is a logic ‘1’, then the SMBus
Host is reading data from the slave device.
See Table 4-1 for available SMBus addresses.
4.2.3 SMBUS DATA BYTES
All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.
4.2.4 SMBUS ACK AND NACK BITS
The SMBus slave will acknowledge all data bytes that it receives. This is done by the slave device pulling the SMBus
Data line low after the 8th bit of each byte that is transmitted. This applies to both the Write Byte and Block Write protocols.
The Host will NACK (not acknowledge) the last data byte to be received from the slave by holding the SMBus data line
high after the 8th data bit has been sent. For the Block Read protocol, the Host will ACK each data byte that it receives
except the last data byte.
4.2.5 SMBUS STOP BIT
The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the
SMBus clock line is in a logic ‘1’ state. When the CAP1128 detects an SMBus Stop bit and it has been communicating
with the SMBus protocol, it will reset its slave interface and prepare to receive further communications.
4.2.6 SMBUS TIMEOUT
The CAP1128 includes an SMBus timeout feature. Following a 30ms period of inactivity on the SMBus where the
SMCLK pin is held low, the device will timeout and reset the SMBus interface.
The timeout function defaults to disabled. It can be enabled by setting the TIMEOUT bit in the Configuration register
(see Section 6.6, "Configuration Registers").
4.2.7 SMBUS AND I2C COMPATIBILITY
The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus
2.0 and I2C specifications. For information on using the CAP1128 in an I2C system, refer to AN 14.0 Dedicated Slave
Devices in I2C Systems.
FIGURE 4-1: SMBus Timing Diagram
SMDATA
SMCLK
TLOW
TRISE
THIGH
TFALL
TBUF
THD:STA
P S S - Start Condition P - Stop Condition
THD:DAT TSU:DAT TSU:STA
THD:STA
P
TSU:STO
S
2015 Microchip Technology Inc. DS00001622B-page 13
CAP1128
1. CAP1128 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz.
2. Minimum frequency for SMBus communications is 10kHz.
3. The SMBus slave protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality
is disabled by default in the CAP1128 and can be enabled by writing to the TIMEOUT bit. I2C does not have
a timeout.
4. The SMBus slave protocol will reset if both the clock and data lines are held at a logic ‘1’ for longer than 200µs
(idle condition). This function is disabled by default in the CAP1128 and can be enabled by writing to the TIMEOUT
bit. I2C does not have an idle condition.
5. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus).
6. I2C devices support block read and write differently. I2C protocol allows for unlimited number of bytes to be sent
in either direction. The SMBus protocol requires that an additional data byte indicating number of bytes to read /
write is transmitted. The CAP1128 supports I2C formatting only.
4.3 SMBus Protocols
The CAP1128 is SMBus 2.0 compatible and supports Write Byte, Read Byte, Send Byte, and Receive Byte as valid
protocols as shown below.
All of the below protocols use the convention in Table 4-2.
4.3.1 SMBUS WRITE BYTE
The Write Byte is used to write one byte of data to a specific register as shown in Table 4-3.
4.3.2 SMBUS READ BYTE
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4-4.
4.3.3 SMBUS SEND BYTE
The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is
transferred during the Send Byte protocol as shown in Table 4-5.
APPLICATION NOTE: The Send Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
TABLE 4-2: PROTOCOL FORMAT
Data Sent to
Device
Data Sent to the
HOst
Data sent Data sent
TABLE 4-3: WRITE BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK Stop
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0 0 -> 1
TABLE 4-4: READ BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data NACK Stop
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-5: SEND BYTE PROTOCOL
Start Slave Address WR ACK Register Address ACK Stop
1 -> 0 YYYY_YYY 0 0 XXh 0 0 -> 1
CAP1128
DS00001622B-page 14 2015 Microchip Technology Inc.
4.3.4 SMBUS RECEIVE BYTE
The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to
be at the right location (e.g., set via Send Byte). This is used for consecutive reads of the same register as shown in
Table 4-6.
APPLICATION NOTE: The Receive Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.4 I2C Protocols
The CAP1128 supports I2C Block Write and Block Read.
The protocols listed below use the convention in Table 4-2.
4.4.1 BLOCK WRITE
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in Table 4-7.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.4.2 BLOCK READ
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in Table 4-8.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.5 SPI Interface
The SMBus has a predefined packet structure, the SPI does not. The SPI Bus can operate in two modes of operation,
normal 4-wire mode and bi-directional 3-wire mode. All SPI commands consist of 8-bit packets sent to a specific slave
device (identified by the CS pin).
The SPI bus will latch data on the rising edge of the clock and the clock and data both idle high.
All commands are supported via both operating modes. The supported commands are: Reset Serial interface, set
address pointer, write command and read command. Note that all other codes received during the command phase are
ignored and have no effect on the operation of the device.
TABLE 4-6: RECEIVE BYTE PROTOCOL
Start Slave Address RD ACK Register Data NACK Stop
1 -> 0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-7: BLOCK WRITE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0
Register Data ACK Register
Data
ACK . . . Register
Data
ACK Stop
XXh 0 XXh 0 . . . XXh 0 0 -> 1
TABLE 4-8: BLOCK READ PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh
ACK Register
Data
ACK Register
Data
ACK Register
Data
ACK . . . Register
Data
NACK Stop
0 XXh 0 XXh 0 XXh 0 . . . XXh 1 0 -> 1
2015 Microchip Technology Inc. DS00001622B-page 15
CAP1128
4.5.1 SPI NORMAL MODE
The SPI Bus can operate in two modes of operation, normal and bi-directional mode. In the normal mode of operation,
there are dedicated input and output data lines. The host communicates by sending a command along the CAP1128
SPI_MOSI data line and reading data on the SPI_MISO data line. Both communications occur simultaneously which
allows for larger throughput of data transactions.
All basic transfers consist of two 8 bit transactions from the Master device while the slave device is simultaneously sending
data at the current address pointer value.
Data writes consist of two or more 8-bit transactions. The host sends a specific write command followed by the data to
write the address pointer. Data reads consist of one or more 8-bit transactions. The host sends the specific read data
command and continues clocking for as many data bytes as it wishes to receive.
4.5.2 SPI BI-DIRECTIONAL MODE
In the bi-directional mode of operation, the SPI data signals are combined into the SPI_MSIO line, which is shared for
data received by the device and transmitted by the device. The protocol uses a simple handshake and turn around
sequence for data communications based on the number of clocks transmitted during each phase.
All basic transfers consist of two 8 bit transactions. The first is an 8 bit command phase driven by the Master device.
The second is by an 8 bit data phase driven by the Master for writes, and by the CAP1128 for read operations.
The auto increment feature of the address pointer allows for successive reads or writes. The address pointer will return
to 00h after reaching FFh.
4.5.3 SPI_CS# PIN
The SPI Bus is a single master, multiple slave serial bus. Each slave has a dedicated CS pin (chip select) that the master
asserts low to identify that the slave is being addressed. There are no formal addressing options.
4.5.4 ADDRESS POINTER
All data writes and reads are accessed from the current address pointer. In both Bi-directional mode and Full Duplex
mode, the Address pointer is automatically incremented following every read command or every write command.
The address pointer will return to 00h after reaching FFh.
4.5.5 SPI TIMEOUT
The CAP1128 does not detect any timeout conditions on the SPI bus.
FIGURE 4-2: SPI Timing
SPI_MSIO or
SPI_MOSI or
SPI_MISO
SPI_CLK
tLOW
tRISE
tHIGH
tFALL
tD:CLK tHD:DAT
tSU:DAT
tP
2015 Microchip Technology Inc. DS00001622B-page 16
CAP1128 4.6 Normal SPI Protocols When operating in normal mode, the SPI bus internal address pointer is incremented depending upon which command has been transmitted. Multiple commands may be transmitted sequentually so long as the SPI_CS# pin is asserted low. Figure 4-3 shows an example of this operation.
4.6.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the transaction - command or data, the receipt of the
successive reset commands resets the Serial communication interface only. All other functions are not affected by the reset operation.
FIGURE 4-3: Example SPI Bus Communication - Normal Mode
SPI_CS#
SPI_MISO
SPI_MOSI
SPI Address Pointer
SPI Data output buffer
Register Address /
Data
7Ah
XXh
(invalid)
XXh
(invalid)
YYh
(invalid)
7Ah 7Dh 41h
YYh
(invalid)
7Eh 66h
XXh
(invalid) 45h
7Dh 41h
AAh
(invalid)
AAh
(invalid)
7Fh 7Fh
55h
(invalid) 66h
7Fh
AAh
7Dh
43h
40h
78h
7Fh
XXh
(invalid)
7Fh
56h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
45h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
55h
7Fh
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
66h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
44h
80h
40h
80h
40h
56h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
43h
55h
7Fh 7Fh
55h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
80h
45h
43h
46h
78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
00h
XXh
Indicates SPI Address pointer incremented
2015 Microchip Technology Inc. DS00001622B-page 17
CAP1128
4.6.2 SET ADDRESS POINTER
The Set Address Pointer command sets the Address pointer for subsequent reads and writes of data. The pointer is set
on the rising edge of the final data bit. At the same time, the data that is to be read is fetched and loaded into the internal
output buffer but is not transmitted.
4.6.3 WRITE DATA
The Write Data protocol updates the contents of the register referenced by the address pointer. As the command is processed,
the data to be read is fetched and loaded into the internal output buffer but not transmitted. Then, the register
is updated with the data to be written. Finally, the address pointer is incremented.
FIGURE 4-4: SPI Reset Interface Command - Normal Mode
FIGURE 4-5: SPI Set Address Pointer Command - Normal Mode
Master SPDOUT
SPI_MOSI
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
Invalid register data 00h – Internal Data buffer empty SPI_MISO
Master Drives Slave Drives
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’
Master SPDOUT
SPI_MOSI Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
SPI_MISO Unknown, Invalid Data Unknown, Invalid Data
Master Drives Slave Drives Address pointer set
‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1128
DS00001622B-page 18 2015 Microchip Technology Inc.
4.6.4 READ DATA
The Read Data protocol is used to read data from the device. During the normal mode of operation, while the device is
receiving data, the CAP1128 is simultaneously transmitting data to the host. For the Set Address commands and the
Write Data commands, this data may be invalid and it is recommended that the Read Data command is used.
FIGURE 4-6: SPI Write Command - Normal Mode
FIGURE 4-7: SPI Read Command - Normal Mode
Master SPDOUT
SPI_MOSI Data to Write
SPI_CS#
SPI_CLK
Write Command – 7Eh
Unknown, Invalid Data Old Data at Current Address Pointer SPI_MISO
Master Drives Slave Drives
1. Data written at current
address pointer
2. Address pointer incremented
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
First Read Command – 7Fh
SPI_CS#
SPI_MISO Invalid, Unknown Data *
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Subsequent Read
Commands – 7F
Data at Current Address Pointer
Address Pointer
Incremented **
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
* The first read command after any other command will return invalid data for the first
byte. Subsequent read commands will return the data at the Current Address Pointer
** The Address Pointer is incremented 8 clocks after the Read Command has been
received. Therefore continually sending Read Commands will result in each command
reporting new data. Once Read Commands have been finished, the last data byte will be
read during the next 8 clocks for any command
2015 Microchip Technology Inc. DS00001622B-page 19
CAP1128
4.7 Bi-Directional SPI Protocols
4.7.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the
transaction - command or data, the receipt of the successive reset commands resets the Serial communication interface
only. All other functions are not affected by the reset operation.
4.7.2 SET ADDRESS POINTER
Sets the address pointer to the register to be accessed by a read or write command. This command overrides the autoincrementing
of the address pointer.
FIGURE 4-8: SPI Read Command - Normal Mode - Full
FIGURE 4-9: SPI Reset Interface Command - Bi-directional Mode
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
Read Command – 7Fh
SPI_CS#
Data at previously set register address = current
address pointer
SPI_MISO ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
XXh
1. Register Read Address
updated to Current SPI Read
Address pointer
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous address
pointer + 1 = current address
pointer
1. Register Read Address
incremented = current address
pointer + 1
1. SPI Read Address
Incremented = new current
address pointer
2. Register Read Address
Incremented = current address
pointer +1
Register Data loaded into
Output buffer = data at current
address pointer + 1
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous register
address pointer + 1 = current
address pointer
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
Subsequent Read Commands – 7Fh
1. Register Read Address
updated to Current SPI Read
Address pointer.
2. Register Read Address
incremented = current address
pointer +1 – end result =
register address pointer doesn’t
change
Master SPDOUT
SPI_MSIO
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1128
DS00001622B-page 20 2015 Microchip Technology Inc.
4.7.3 WRITE DATA
Writes data value to the register address stored in the address pointer. Performs auto increment of address pointer after
the data is loaded into the register.
4.7.4 READ DATA
Reads data referenced by the address pointer. Performs auto increment of address pointer after the data is transferred
to the Master.
FIGURE 4-10: SPI Set Address Pointer Command - Bi-directional Mode
FIGURE 4-11: SPI Write Data Command - Bi-directional Mode
FIGURE 4-12: SPI Read Data Command - Bi-directional Mode
Master SPDOUT
SPI_MSIO Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
‘0’ ‘1’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Master SPDOUT
SPI_MSIO Register Write Data
SPI_CS#
SPI_CLK
Write Command – 7Eh
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’
Master SPDOUT
SPI_MSIO
Master Drives Slave Drives Indeterminate
Register Read Data
SPI_CLK
Read Command – 7Fh
SPI_CS#
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
2015 Microchip Technology Inc. DS00001622B-page 21
CAP1128
4.8 BC-Link Interface
The BC-Link is a proprietary bus developed to allow communication between a host controller device to a companion
device. This device uses this serial bus to read and write registers and for interrupt processing. The interface uses a
data port concept, where the base interface has an address register, data register and a control register, defined in the
8051’s SFR space.
Refer to documentation for the BC-Link compatible host controller for details on how to access the CAP1128 via the BCLink
Interface.
CAP1128
DS00001622B-page 22 2015 Microchip Technology Inc.
5.0 GENERAL DESCRIPTION
The CAP1128 is a multiple channel Capacitive Touch sensor with multiple power LED drivers. It contains eight (8) individual
capacitive touch sensor inputs with programmable sensitivity for use in touch sensor applications. Each sensor
input automatically recalibrates to compensate for gradual environmental changes.
The CAP1128 also contains two (2) low side (or push-pull) LED drivers that offer full-on / off, variable rate blinking, dimness
controls, and breathing. Each of the LED drivers may be linked to one of the sensor inputs to be actuated when a
touch is detected. As well, each LED driver may be individually controlled via a host controller.
Finally, the device contains a dedicated RESET pin to act as a soft reset by the system.
The CAP1128 offers multiple power states. It operates at the lowest quiescent current during its Deep Sleep state. In
the low power Standby state, it can monitor one or more channels and respond to communications normally. The device
contains a wake pin (WAKE/SPI_MOSI) output to wake the system when a touch is detected in Standby and to wake
the device from Deep Sleep.
The device communicates with a host controller using the SPI bus, or via SMBus / I2C. The host controller may poll the
device for updated information at any time or it may configure the device to flag an interrupt whenever a touch is
detected on any sensor pad.
A typical system diagram is shown in Figure 5-1.
2015 Microchip Technology Inc. DS00001622B-page 23
CAP1128
FIGURE 5-1: System Diagram for CAP1128
CAP1128
CS6
SMDATA / BC_DATA / SPI_MSIO / SPI_MISO
SMCLK / BC_CLK / SPI_CLK
VDD Embedded Controller ALERT# / BC_IRQ#
CS4
CS2
3.3V – 5V
CS5
CS3
CS1
WAKE / SPI_MOSI
CS7 CS8 RESET SPI_CS#
ADDR_COMM
LED1 LED2
3.3V – 5V
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
CAP1128
DS00001622B-page 24 2015 Microchip Technology Inc.
5.1 Power States
The CAP1128 has three operating states depending on the status of the STBY and DSLEEP bits. When the device transitions
between power states, previously detected touches (for inactive channels) are cleared and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active capacitive sensor inputs and driving all LED channels
as defined.
2. Standby - The device is in a lower power state. It will measure a programmable number of channels using the
Standby Configuration controls (see Section 6.20 through Section 6.22). Interrupts will still be generated based
on the active channels. The device will still respond to communications normally and can be returned to the Fully
Active state of operation by clearing the STBY bit.
3. Deep Sleep - The device is in its lowest power state. It is not monitoring any capacitive sensor inputs and not
driving any LEDs. All LEDs will be driven to their programmed non-actuated state and no PWM operations will
be done. While in Deep Sleep, the device can be awakened by SMBus or SPI communications targeting the
device. This will not cause the DSLEEP to be cleared so the device will return to Deep Sleep once all communications
have stopped.
If the device is not communicating via the 4-wire SPI bus, then during this state of operation, if the WAKE/SPI_MOSI
pin is driven high by an external source, the device will clear the DSLEEP bit and return to Fully Active.
APPLICATION NOTE: In the Deep Sleep state, the LED output will be either high or low and will not be PWM’d at
the min or max duty cycle.
5.2 RESET Pin
The RESET pin is an active high reset that is driven from an external source. While it is asserted high, all the internal
blocks will be held in reset including the communications protocol used. No capacitive touch sensor inputs will be sampled
and the LEDs will not be driven. All configuration settings will be reset to default states and all readings will be
cleared.
The device will be held in Deep Sleep that can only be removed by driving the RESET pin low. This will cause the
RESET status bit to be set to a logic ‘1’ and generate an interrupt.
5.3 WAKE/SPI_MOSI Pin Operation
The WAKE / SPI_MOSI pin is a multi-function pin depending on device operation. When the device is configured to communicate
using the 4-wire SPI bus, this pin is an input.
However, when the CAP1128 is placed in Standby and is not communicating using the 4-wire SPI protocol, the WAKE
pin is an active high output. In this condition, the device will assert the WAKE/SPI_MOSI pin when a touch is detected
on one of its sampled sensor inputs. The pin will remain asserted until the INT bit has been cleared and then it will be
de-asserted.
When the CAP1128 is placed in Deep Sleep and it is not communicating using the 4-wire SPI protocol, the WAKE/SPI_-
MOSI pin is monitored by the device as an input. If the WAKE/SPI_MOSI pin is driven high by an external source, the
CAP1128will clear the DSLEEP bit causing the device to return to Fully Active.
When the device is placed in Deep Sleep, this pin is a High-Z input and must have a pull-down resistor to GND for proper
operation.
5.4 LED Drivers
The CAP1128 contains two (2) LED drivers. Each LED driver can be linked to its respective capacitive touch sensor
input or it can be controlled by the host. Each LED driver can be configured to operate in one of the following modes
with either push-pull or open drain drive.
1. Direct - The LED is configured to be on or off when the corresponding input stimulus is on or off (or inverted). The
brightness of the LED can be programmed from full off to full on (default). Additionally, the LED contains controls
to individually configure ramping on, off, and turn-off delay.
2. Pulse 1 - The LED is configured to “Pulse” (transition ON-OFF-ON) a programmable number of times with programmable
rate and min / max brightness. This behavior may be actuated when a press is detected or when a
release is detected.
3. Pulse 2 - The LED is configured to “Pulse” while actuated and then “Pulse” a programmable number of times with
programmable rate and min / max brightness when the sensor pad is released.
2015 Microchip Technology Inc. DS00001622B-page 25
CAP1128
4. Breathe - The LED is configured to transition continuously ON-OFF-ON (i.e. to “Breathe”) with a programmable
rate and min / max brightness.
When an LED is not linked to a sensor and is actuated by the host, there’s an option to assert the ALERT# pin when
the initiated LED behavior has completed.
5.4.1 LINKING LEDS TO CAPACITIVE TOUCH SENSOR INPUTS
All LEDs can be linked to the corresponding capacitive touch sensor input so that when the sensor input detects a touch,
the corresponding LED will be actuated at one of the programmed responses.
5.5 Capacitive Touch Sensing
The CAP1128 contains eight (8) independent capacitive touch sensor inputs. Each sensor input has dynamic range to
detect a change of capacitance due to a touch. Additionally, each sensor input can be configured to be automatically
and routinely re-calibrated.
5.5.1 SENSING CYCLE
Each capacitive touch sensor input has controls to be activated and included in the sensing cycle. When the device is
active, it automatically initiates a sensing cycle and repeats the cycle every time it finishes. The cycle polls through each
active sensor input starting with CS1 and extending through CS8. As each capacitive touch sensor input is polled, its
measurement is compared against a baseline “Not Touched” measurement. If the delta measurement is large enough,
a touch is detected and an interrupt is generated.
The sensing cycle time is programmable (see Section 6.10, "Averaging and Sampling Configuration Register").
5.5.2 RECALIBRATING SENSOR INPUTS
There are various options for recalibrating the capacitive touch sensor inputs. Recalibration re-sets the Base Count Registers
(Section 6.24, "Sensor Input Base Count Registers") which contain the “not touched” values used for touch detection
comparisons.
APPLICATION NOTE: The device will recalibrate all sensor inputs that were disabled when it transitions from
Standby. Likewise, the device will recalibrate all sensor inputs when waking out of Deep
Sleep.
5.5.2.1 Manual Recalibration
The Calibration Activate Registers (Section 6.11, "Calibration Activate Register") force recalibration of selected sensor
inputs. When a bit is set, the corresponding capacitive touch sensor input will be recalibrated (both analog and digital).
The bit is automatically cleared once the recalibration routine has finished.
5.5.2.2 Automatic Recalibration
Each sensor input is regularly recalibrated at a programmable rate (see Section 6.17, "Recalibration Configuration Register").
By default, the recalibration routine stores the average 64 previous measurements and periodically updates the
base “not touched” setting for the capacitive touch sensor input.
Note: During this recalibration routine, the sensor inputs will not detect a press for up to 200ms and the Sensor
Base Count Register values will be invalid. In addition, any press on the corresponding sensor pads will
invalidate the recalibration.
Note: Automatic recalibration only works when the delta count is below the active sensor input threshold. It is disabled
when a touch is detected.
CAP1128
DS00001622B-page 26 2015 Microchip Technology Inc.
5.5.2.3 Negative Delta Count Recalibration
It is possible that the device loses sensitivity to a touch. This may happen as a result of a noisy environment, an accidental
recalibration during a touch, or other environmental changes. When this occurs, the base untouched sensor input
may generate negative delta count values. The NEG_DELTA_CNT bits (see Section 6.17, "Recalibration Configuration
Register") can be set to force a recalibration after a specified number of consecutive negative delta readings.
5.5.2.4 Delayed Recalibration
It is possible that a “stuck button” occurs when something is placed on a button which causes a touch to be detected
for a long period. By setting the MAX_DUR_EN bit (see Section 6.6, "Configuration Registers"), a recalibration can be
forced when a touch is held on a button for longer than the duration specified in the MAX_DUR bits (see Section 6.8,
"Sensor Input Configuration Register").
5.5.3 PROXIMITY DETECTION
Each sensor input can be configured to detect changes in capacitance due to proximity of a touch. This circuitry detects
the change of capacitance that is generated as an object approaches, but does not physically touch, the enabled sensor
pad(s). When a sensor input is selected to perform proximity detection, it will be sampled from 1x to 128x per sampling
cycle. The larger the number of samples that are taken, the greater the range of proximity detection is available at the
cost of an increased overall sampling time.
5.5.4 MULTIPLE TOUCH PATTERN DETECTION
The multiple touch pattern (MTP) detection circuitry can be used to detect lid closure or other similar events. An event
can be flagged based on either a minimum number of sensor inputs or on specific sensor inputs simultaneously exceeding
an MTP threshold or having their Noise Flag Status Register bits set. An interrupt can also be generated. During an
MTP event, all touches are blocked (see Section 6.15, "Multiple Touch Pattern Configuration Register").
5.5.5 LOW FREQUENCY NOISE DETECTION
Each sensor input has an EMI noise detector that will sense if low frequency noise is injected onto the input with sufficient
power to corrupt the readings. If this occurs, the device will reject the corrupted sample and set the corresponding
bit in the Noise Status register to a logic ‘1’.
5.5.6 RF NOISE DETECTION
Each sensor input contains an integrated RF noise detector. This block will detect injected RF noise on the CS pin. The
detector threshold is dependent upon the noise frequency. If RF noise is detected on a CS line, that sample is removed
and not compared against the threshold.
5.6 ALERT# Pin
The ALERT# pin is an active low (or active high when configured) output that is driven when an interrupt event is
detected.
Whenever an interrupt is generated, the INT bit (see Section 6.1, "Main Control Register") is set. The ALERT# pin is
cleared when the INT bit is cleared by the user. Additionally, when the INT bit is cleared by the user, status bits are only
cleared if no touch is detected.
5.6.1 SENSOR INTERRUPT BEHAVIOR
The sensor interrupts are generated in one of two ways:
1. An interrupt is generated when a touch is detected and, as a user selectable option, when a release is detected
(by default - see Section 6.6). See Figure 5-3.
2. If the repeat rate is enabled then, so long as the touch is held, another interrupt will be generated based on the
programmed repeat rate (see Figure 5-2).
Note: During this recalibration, the device will not respond to touches.
Note: Delayed recalibration only works when the delta count is above the active sensor input threshold. If
enabled, it is invoked when a sensor pad touch is held longer than the MAX_DUR bit setting.
2015 Microchip Technology Inc. DS00001622B-page 27
CAP1128
When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch
is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button
is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a
touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it
is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed
repeat rate and upon release (if enabled).
APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon
sensor pad release and an active-low ALERT# pin.
APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.
FIGURE 5-2: Sensor Interrupt Behavior - Repeat Rate Enabled
FIGURE 5-3: Sensor Interrupt Behavior - No Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms)
Min Press Setting
(280ms)
Interrupt on
Touch
Button Repeat Rate
(175ms)
Button Repeat Rate
(175ms)
Interrupt on
Release
(optional)
ALERT# pin
(active low)
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms) Interrupt on
Touch Interrupt on
Release
(optional)
ALERT# pin
(active low)
CAP1128
DS00001622B-page 28 2015 Microchip Technology Inc.
6.0 REGISTER DESCRIPTION
The registers shown in Table 6-1 are accessible through the communications protocol. An entry of ‘-’ indicates that the
bit is not used and will always read ‘0’.
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER
Register
Address R/W Register Name Function Default Value Page
00h R/W Main Control Controls general power states and
power dissipation 00h Page 31
02h R General Status Stores general status bits 00h Page 32
03h R Sensor Input Status Returns the state of the sampled
capacitive touch sensor inputs 00h Page 32
04h R LED Status Stores status bits for LEDs 00h Page 32
0Ah R Noise Flag Status Stores the noise flags for sensor inputs 00h Page 33
10h R Sensor Input 1 Delta
Count Stores the delta count for CS1 00h Page 34
11h R Sensor Input 2 Delta
Count Stores the delta count for CS2 00h Page 34
12h R Sensor Input 3 Delta
Count Stores the delta count for CS3 00h Page 34
13h R Sensor Input 4 Delta
Count Stores the delta count for CS4 00h Page 34
14h R Sensor Input 5 Delta
Count Stores the delta count for CS5 00h Page 34
15h R Sensor Input 6 Delta
Count Stores the delta count for CS6 00h Page 34
16h R Sensor Input 7 Delta
Count Stores the delta count for CS7 00h Page 34
17h R Sensor Input 8 Delta
Count Stores the delta count for CS8 00h Page 34
1Fh R/W Sensitivity Control
Controls the sensitivity of the threshold
and delta counts and data scaling of
the base counts
2Fh Page 34
20h R/W Configuration Controls general functionality 20h Page 36
21h R/W Sensor Input Enable Controls whether the capacitive touch
sensor inputs are sampled FFh Page 37
22h R/W Sensor Input Configuration
Controls max duration and auto-repeat
delay for sensor inputs operating in the
full power state
A4h Page 38
23h R/W Sensor Input Configuration
2
Controls the MPRESS controls for all
sensor inputs 07h Page 39
24h R/W Averaging and Sampling
Config
Controls averaging and sampling window
39h Page 39
26h R/W Calibration Activate Forces re-calibration for capacitive
touch sensor inputs 00h Page 41
27h R/W Interrupt Enable Enables Interrupts associated with
capacitive touch sensor inputs FFh Page 41
28h R/W Repeat Rate Enable Enables repeat rate for all sensor
inputs FFh Page 42
2Ah R/W Multiple Touch Configuration
Determines the number of simultaneous
touches to flag a multiple touch
condition
80h Page 42
2015 Microchip Technology Inc. DS00001622B-page 29
CAP1128
2Bh R/W Multiple Touch Pattern
Configuration
Determines the multiple touch pattern
(MTP) configuration 00h Page 43
2Dh R/W Multiple Touch Pattern
Determines the pattern or number of
sensor inputs used by the MTP circuitry
FFh Page 44
2Fh R/W Recalibration Configuration
Determines re-calibration timing and
sampling window 8Ah Page 44
30h R/W Sensor Input 1 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 1
40h Page 46
31h R/W Sensor Input 2 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 2
40h Page 46
32h R/W Sensor Input 3 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 3
40h Page 46
33h R/W Sensor Input 4 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 4
40h Page 46
34h R/W Sensor Input 5 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 5
40h Page 46
35h R/W Sensor Input 6 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 6
40h Page 46
36h R/W Sensor Input 7 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 7
40h Page 46
37h R/W Sensor Input 8 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 8
40h
38h R/W Sensor Input Noise
Threshold
Stores controls for selecting the noise
threshold for all sensor inputs 01h Page 46
Standby Configuration Registers
40h R/W Standby Channel Controls which sensor inputs are
enabled while in standby 00h Page 47
41h R/W Standby Configuration Controls averaging and cycle time
while in standby 39h Page 47
42h R/W Standby Sensitivity Controls sensitivity settings used while
in standby 02h Page 48
43h R/W Standby Threshold Stores the touch detection threshold
for active sensor inputs in standby 40h Page 49
44h R/W Configuration 2 Stores additional configuration controls
for the device 40h Page 36
Base Count Registers
50h R Sensor Input 1 Base
Count
Stores the reference count value for
sensor input 1 C8h Page 49
51h R Sensor Input 2 Base
Count
Stores the reference count value for
sensor input 2 C8h Page 49
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1128
DS00001622B-page 30 2015 Microchip Technology Inc.
52h R Sensor Input 3 Base
Count
Stores the reference count value for
sensor input 3 C8h Page 49
53h R Sensor Input 4 Base
Count
Stores the reference count value for
sensor input 4 C8h Page 49
54h R Sensor Input 5 Base
Count
Stores the reference count value for
sensor input 5 C8h Page 49
55h R Sensor Input 6 Base
Count
Stores the reference count value for
sensor input 6 C8h Page 49
56h R Sensor Input 7 Base
Count
Stores the reference count value for
sensor input 7 C8h Page 49
57h R Sensor Input 8 Base
Count
Stores the reference count value for
sensor input 8 C8h Page 49
LED Controls
71h R/W LED Output Type Controls the output type for the LED
outputs 00h Page 50
72h R/W Sensor Input LED Linking
Controls linking of sensor inputs to
LED channels 00h Page 50
73h R/W LED Polarity Controls the output polarity of LEDs 00h Page 50
74h R/W LED Output Control Controls the output state of the LEDs 00h Page 51
77h R/W Linked LED
Transition Control
Controls the transition when LEDs are
linked to CS channels 00h Page 52
79h R/W LED Mirror Control Controls the mirroring of duty cycles
for the LEDs 00h Page 53
81h R/W LED Behavior 1 Controls the behavior and response of
LEDs 1 - 2 00h Page 53
84h R/W LED Pulse 1 Period Controls the period of each breathe
during a pulse 20h Page 55
85h R/W LED Pulse 2 Period Controls the period of the breathing
during breathe and pulse operation 14h Page 56
86h R/W LED Breathe Period Controls the period of an LED breathe
operation 5Dh Page 57
88h R/W LED Config Controls LED configuration 04h Page 58
90h R/W LED Pulse 1 Duty Cycle Determines the min and max duty
cycle for the pulse operation F0h Page 58
91h R/W LED Pulse 2 Duty Cycle Determines the min and max duty
cycle for breathe and pulse operation F0h Page 58
92h R/W LED Breathe Duty Cycle Determines the min and max duty
cycle for the breathe operation F0h Page 58
93h R/W LED Direct Duty Cycle Determines the min and max duty
cycle for Direct mode LED operation F0h Page 58
94h R/W LED Direct Ramp Rates Determines the rising and falling edge
ramp rates of the LEDs 00h Page 59
95h R/W LED Off Delay Determines the off delay for all LED
behaviors 00h Page 60
B1h R Sensor Input 1 Calibration
Stores the upper 8-bit calibration value
for sensor input 1 00h Page 63
B2h R Sensor Input 2 Calibration
Stores the upper 8-bit calibration value
for sensor input 2 00h Page 63
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001622B-page 31
CAP1128
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first
applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics.
Any reads to undefined registers will return 00h. Writes to undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means that the user writes
a logic ‘0’ to it.
6.1 Main Control Register
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is increased, the
effective sensitivity is likewise increased as a smaller delta capacitance is required to generate the same delta count
values. The sensitivity settings may need to be adjusted along with the gain settings such that data overflow does not
occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
B3h R Sensor Input 3 Calibration
Stores the upper 8-bit calibration value
for sensor input 3 00h Page 63
B4h R Sensor Input 4 Calibration
Stores the upper 8-bit calibration value
for sensor input 4 00h Page 63
B5h R Sensor Input 5 Calibration
Stores the upper 8-bit calibration value
for sensor input 5 00h Page 63
B6h R Sensor Input 6 Calibration
Stores the upper 8-bit calibration value
for sensor input 6 00h Page 63
B7h R Sensor Input 7 Calibration
Stores the upper 8-bit calibration value
for sensor input 7 00h Page 63
B8h R Sensor Input 8 Calibration
Stores the upper 8-bit calibration value
for sensor input 8 00h Page 63
B9h R Sensor Input Calibration
LSB 1
Stores the 2 LSBs of the calibration
value for sensor inputs 1 - 4 00h Page 63
BAh R Sensor Input Calibration
LSB 2
Stores the 2 LSBs of the calibration
value for sensor inputs 5 - 8 00h Page 63
FDh R Product ID Stores a fixed value that identifies
each product 52h Page 63
FEh R Manufacturer ID Stores a fixed value that identifies
Microchip 5Dh Page 64
FFh R Revision Stores a fixed value that represents
the revision number 83h Page 64
TABLE 6-2: MAIN CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
00h R/W Main Control GAIN[1:0] STBY DSLEEP - - - INT 00h
TABLE 6-3: GAIN BIT DECODE
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
0 0 1
01 2
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
CAP1128
DS00001622B-page 32 2015 Microchip Technology Inc.
Bit 5 - STBY - Enables Standby.
• ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - Capacitive touch sensor input scanning is limited to the sensor inputs set in the Standby Channel register (see
Section 6.20). The status registers will not be cleared until read. LEDs that are linked to capacitive touch sensor
inputs will remain linked and active. Sensor inputs that are no longer sampled will flag a release and then remain
in a non-touched state. LEDs that are manually controlled will be unaffected.
• Bit 4 - DSLEEP - Enables Deep Sleep by deactivating all functions. This bit will be cleared when the WAKE pin is
driven high. ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - All sensor input scanning is disabled. All LEDs are driven to their programmed non-actuated state and no
PWM operations will be done. The status registers are automatically cleared and the INT bit is cleared.
Bit 0 - INT - Indicates that there is an interrupt. When this bit is set, it asserts the ALERT# pin. If a channel detects a
touch and its associated interrupt enable bit is not set to a logic ‘1’, no action is taken.
This bit is cleared by writing a logic ‘0’ to it. When this bit is cleared, the ALERT# pin will be deasserted and all status
registers will be cleared if the condition has been removed. If the WAKE/SPI_MOSI pin is asserted as a result of a touch
detected while in Standby, it will likewise be deasserted when this bit is cleared.
Note that the WAKE / SPI_MOSI pin is not driven when communicating via the 4-wire SPI protocol.
• ‘0’ - No interrupt pending.
• ‘1’ - A touch has been detected on one or more channels and the interrupt has been asserted.
6.2 Status Registers
All status bits are cleared when the device enters the Deep Sleep (DSLEEP = ‘1’ - see Section 6.1).
6.2.1 GENERAL STATUS - 02H
Bit 4 - LED - Indicates that one or more LEDs have finished their programmed activity. This bit is set if any bit in the LED
Status register is set.
Bit 3 - RESET - Indicates that the device has come out of reset. This bit is set when the device exits a POR state or
when the RESET pin has been deasserted and qualified via the RESET pin filter (see Section 5.2). This bit will cause
the INT bit to be set and is cleared when the INT bit is cleared.
Bit 2 - MULT - Indicates that the device is blocking detected touches due to the Multiple Touch detection circuitry (see
Section 6.14). This bit will not cause the INT bit to be set and hence will not cause an interrupt.
Bit 1 - MTP - Indicates that the device has detected a number of sensor inputs that exceed the MTP threshold either via
the pattern recognition or via the number of sensor inputs (see Section 6.15). This bit will cause the INT bit to be set if
the MTP_ALERT bit is also set. This bit will not be cleared until the condition that caused it to be set has been removed.
Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status register is set.
10 4
11 8
TABLE 6-4: STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
02h R General Status - - - LED RESET MULT MTP TOUCH 00h
03h R Sensor Input Status
CS8 CS7 CS6 CS5 CS4 CS3 CS2 CS1 00h
04h R LED Status - - - - - - LED2_
DN
LED1_
DN 00h
TABLE 6-3: GAIN BIT DECODE (CONTINUED)
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
2015 Microchip Technology Inc. DS00001622B-page 33
CAP1128
6.2.2 SENSOR INPUT STATUS - 03H
The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value of ‘0’ in any bit
indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a touch has been detected.
All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor input is no longer
present. If a touch is still detected, the bits will not be cleared (but this will not cause the interrupt to be asserted - see
Section 6.6).
Bit 7 - CS8 - Indicates that a touch was detected on Sensor Input 8.
Bit 6 - CS7 - Indicates that a touch was detected on Sensor Input 7.
Bit 5 - CS6 - Indicates that a touch was detected on Sensor Input 6.
Bit 4 - CS5 - Indicates that a touch was detected on Sensor Input 5.
Bit 3 - CS4 - Indicates that a touch was detected on Sensor Input 4.
Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3.
Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2. This sensor input can be linked to LED2.
Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1. This sensor input can be linked to LED1.
6.2.3 LED STATUS - 04H
The LED Status Registers indicate when an LED has completed its configured behavior (see Section 6.31, "LED Behavior
Register") after being actuated by the host (see Section 6.28, "LED Output Control Register"). These bits are ignored
when the LED is linked to a capacitive sensor input. All LED Status bits are cleared when the INT bit is cleared.
Bit 1 - LED2_DN - Indicates that LED2 has finished its behavior after being actuated by the host.
Bit 0 - LED1_DN - Indicates that LED1 has finished its behavior after being actuated by the host.
6.3 Noise Flag Status Registers
The Noise Flag Status registers store status bits that are generated from the analog block if the detected noise is above
the operating region of the analog detector or the RF noise detector. These bits indicate that the most recently received
data from the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a particular
channel, the delta count value is reset to 00h and thus no touch is detected.
These bits are not sticky and will be cleared automatically if the analog block does not report a noise error.
APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP
threshold (see Section 5.5.4, "Multiple Touch Pattern Detection") even if the corresponding
delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not
counted twice.
APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a
sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,
if RF noise is detected on a sensor input, that sample will be discarded unless the
DIS_RF_NOISE bit is set.
TABLE 6-5: NOISE FLAG STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
0Ah R Noise Flag Status CS8_
NOISE
CS7_
NOISE
CS6_
NOISE
CS5_
NOISE
CS4_
NOISE
CS3_
NOISE
CS2_
NOISE
CS1_
NOISE 00h
CAP1128
DS00001622B-page 34 2015 Microchip Technology Inc.
6.4 Sensor Input Delta Count Registers
The Sensor Input Delta Count registers store the delta count that is compared against the threshold used to determine
if a touch has been detected. The count value represents a change in input due to the capacitance associated with a
touch on one of the sensor inputs and is referenced to a calibrated base “Not Touched” count value. The delta is an
instantaneous change and is updated once per sensor input per sensing cycle (see Section 5.5.1, "Sensing Cycle").
The value presented is a standard 2’s complement number. In addition, the value is capped at a value of 7Fh. A reading
of 7Fh indicates that the sensitivity settings are too high and should be adjusted accordingly (see Section 6.5).
The value is also capped at a negative value of 80h for negative delta counts which may result upon a release.
6.5 Sensitivity Control Register
The Sensitivity Control register controls the sensitivity of a touch detection.
Bits 6-4 DELTA_SENSE[2:0] - Controls the sensitivity of a touch detection. The sensitivity settings act to scale the relative
delta count value higher or lower based on the system parameters. A setting of 000b is the most sensitive while a
setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a smaller delta capacitance
corresponding to a “lighter” touch. These settings are more sensitive to noise, however, and a noisy environment may
flag more false touches with higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely, a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
TABLE 6-6: SENSOR INPUT DELTA COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
10h R Sensor Input 1
Delta Count Sign 64 32 16 8 4 2 1 00h
11h R Sensor Input 2
Delta Count Sign 64 32 16 8 4 2 1 00h
12h R Sensor Input 3
Delta Count Sign 64 32 16 8 4 2 1 00h
13h R Sensor Input 4
Delta Count Sign 64 32 16 8 4 2 1 00h
14h R Sensor Input 5
Delta Count Sign 64 32 16 8 4 2 1 00h
15h R Sensor Input 6
Delta Count Sign 64 32 16 8 4 2 1 00h
16h R Sensor Input 7
Delta Count Sign 64 32 16 8 4 2 1 00h
17h R Sensor Input 8
Delta Count Sign 64 32 16 8 4 2 1 00h
TABLE 6-7: SENSITIVITY CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
1Fh R/W Sensitivity Control - DELTA_SENSE[2:0] BASE_SHIFT[3:0] 2Fh
2015 Microchip Technology Inc. DS00001622B-page 35
CAP1128
Bits 3 - 0 - BASE_SHIFT[3:0] - Controls the scaling and data presentation of the Base Count registers. The higher the
value of these bits, the larger the range and the lower the resolution of the data presented. The scale factor represents
the multiplier to the bit-weighting presented in these register descriptions.
APPLICATION NOTE: The BASE_SHIFT[3:0] bits normally do not need to be updated. These settings will not affect
touch detection or sensitivity. These bits are sometimes helpful in analyzing the Cap Sensing
board performance and stability.
TABLE 6-8: DELTA_SENSE BIT DECODE
DELTA_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-9: BASE_SHIFT BIT DECODE
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
0 0 0 0 1x
0 0 0 1 2x
0 0 1 0 4x
0 0 1 1 8x
0 1 0 0 16x
0 1 0 1 32x
0 1 1 0 64x
0 1 1 1 128x
1 0 0 0 256x
All others 256x
(default = 1111b)
CAP1128
DS00001622B-page 36 2015 Microchip Technology Inc.
6.6 Configuration Registers
The Configuration registers control general global functionality that affects the entire device.
6.6.1 CONFIGURATION - 20H
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
• ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The SMBus interface
will not time out if the clock line is held low. Likewise, it will not reset if both the data and clock lines are held
high for longer than 200us. This is used for I2C compliance.
• ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The SMBus interface
will time out if the clock line is held low for longer than 30ms. Likewise, it will reset if both the data and clock
lines are held high for longer than 200us.
Bit 6 - WAKE_CFG - Configures the operation of the WAKE pin.
• ‘0’ (default) - The WAKE pin is not asserted when a touch is detected while the device is in Standby. It will still be
used to wake the device from Deep Sleep when driven high.
• ‘1’ - The WAKE pin will be asserted high when a touch is detected while the device is in Standby. It will also be
used to wake the device from Deep Sleep when driven high.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 6.19, "Sensor Input Noise Threshold
Register") is used by the device. Setting this bit disables the feature.
• ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does not exceed the
touch threshold, the sample is discarded and not used for the automatic re-calibration routine.
• ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold is used for the
automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the corresponding channel
is set to 0. Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
• ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held indefinitely and no
re-calibration will be performed on any sensor input.
• ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than the MAX_DUR
bit settings, then the re-calibration routine will be restarted (see Section 6.8).
6.6.2 CONFIGURATION 2 - 44H
Bit 7 - INV_LINK_TRAN - Determines the behavior of the Linked LED Transition controls (see Section 6.29).
• ‘0’ (default) - The Linked LED Transition controls set the min duty cycle equal to the max duty cycle.
• ‘1’ - The Linked LED Transition controls will invert the touch signal. For example, a touch signal will be inverted to
a non-touched signal.
Bit 6 - ALT_POL - Determines the ALERT# pin polarity and behavior.
• ‘0’ - The ALERT# pin is active high and push-pull.
• ‘1’ (default) - The ALERT# pin is active low and open drain.
TABLE 6-10: CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
20h R/W Configuration TIMEOUT WAKE_
CFG
DIS_ DIG_
NOISE
DIS_ ANA_
NOISE
MAX_
DUR_EN - --
A0h
(Rev B)
20h
(rev C)
44h R/W Configuration 2 INV_LINK_
TRAN
ALT_
POL
BLK_PWR_
CTRL
BLK_POL_
MIR
SHOW_
RF_
NOISE
DIS_
RF_
NOISE
- INT_
REL_n 40h
2015 Microchip Technology Inc. DS00001622B-page 37
CAP1128
Bit 5 - BLK_PWR_CTRL - Determines whether the device will reduce power consumption while waiting between conversion
time completion and the end of the polling cycle.
• ‘0’ (default) - The device will always power down as much as possible during the time between the end of the last
conversion and the end of the polling cycle.
• ‘1’ - The device will not power down the Cap Sensor during the time between the end of the last conversion and
the end of the polling cycle.
Bit 4 - BLK_POL_MIR - Determines whether the LED Mirror Control register bits are linked to the LED Polarity bits. Setting
this bit blocks the normal behavior which is to automatically set and clear the LED Mirror Control bits when the LED
Polarity bits are set or cleared.
• ‘0’ (default) - When the LED Polarity controls are set, the corresponding LED Mirror control is automatically set.
Likewise, when the LED Polarity controls are cleared, the corresponding LED Mirror control is also cleared.
• ‘1’ - When the LED Polarity controls are set, the corresponding LED Mirror control is not automatically set.
Bit 3 - SHOW_RF_NOISE - Determines whether the Noise Status bits will show RF Noise as the only input source.
• ‘0’ (default) - The Noise Status registers will show both RF noise and low frequency EMI noise if either is detected
on a capacitive touch sensor input.
• ‘1’ - The Noise Status registers will only show RF noise if it is detected on a capacitive touch sensor input. EMI
noise will still be detected and touches will be blocked normally; however, the status bits will not be updated.
Bit 2 - DIS_RF_NOISE - Determines whether the RF noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If RF noise is detected by the analog block, the delta count on the corresponding channel is set to 0.
Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if RF noise is detected.
Bit 0 - INT_REL_n - Controls the interrupt behavior when a release is detected on a button.
• ‘0’ (default) - An interrupt is generated when a press is detected and again when a release is detected and at the
repeat rate (if enabled - see Section 6.13).
• ‘1’ - An interrupt is generated when a press is detected and at the repeat rate but not when a release is detected.
6.7 Sensor Input Enable Registers
The Sensor Input Enable registers determine whether a capacitive touch sensor input is included in the sampling cycle.
The length of the sampling cycle is not affected by the number of sensor inputs measured.
Bit 7 - CS8_EN - Enables the CS8 input to be included during the sampling cycle.
• ‘0’ - The CS8 input is not included in the sampling cycle.
• ‘1’ (default) - The CS8 input is included in the sampling cycle.
Bit 6 - CS7_EN - Enables the CS7 input to be included during the sampling cycle.
Bit 5 - CS6_EN - Enables the CS6 input to be included during the sampling cycle.
Bit 4 - CS5_EN - Enables the CS5 input to be included during the sampling cycle.
Bit 3 - CS4_EN - Enables the CS4 input to be included during the sampling cycle.
Bit 2 - CS3_EN - Enables the CS3 input to be included during the sampling cycle.
Bit 1 - CS2_EN - Enables the CS2 input to be included during the sampling cycle.
Bit 0 - CS1_EN - Enables the CS1 input to be included during the sampling cycle.
TABLE 6-11: SENSOR INPUT ENABLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
21h R/W Sensor Input
Enable CS8_EN CS7_EN CS6_EN CS5_EN CS4_EN CS3_EN CS2_EN CS1_EN FFh
CAP1128
DS00001622B-page 38 2015 Microchip Technology Inc.
6.8 Sensor Input Configuration Register
The Sensor Input Configuration Register controls timings associated with the Capacitive sensor inputs 1 - 8.
Bits 7 - 4 - MAX_DUR[3:0] - (default 1010b) - Determines the maximum time that a sensor pad is allowed to be touched
until the capacitive touch sensor input is recalibrated, as shown in Table 6-13.
Bits 3 - 0 - RPT_RATE[3:0] - (default 0100b) Determines the time duration between interrupt assertions when auto
repeat is enabled. The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-14.
TABLE 6-12: SENSOR INPUT CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
22h R/W Sensor Input
Configuration MAX_DUR[3:0] RPT_RATE[3:0] A4h
TABLE 6-13: MAX_DUR BIT DECODE
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
0 0 0 0 560ms
0 0 0 1 840ms
0 0 1 0 1120ms
0 0 1 1 1400ms
0 1 0 0 1680ms
0 1 0 1 2240ms
0 1 1 0 2800ms
1 1 1 3360ms
1 0 0 0 3920ms
1 0 0 1 4480ms
1 0 1 0 5600ms (default)
1 0 1 1 6720ms
1 1 0 0 7840ms
1 1 0 1 8906ms
1 1 1 0 10080ms
1 1 1 1 11200ms
TABLE 6-14: RPT_RATE BIT DECODE
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms (default)
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
2015 Microchip Technology Inc. DS00001622B-page 39
CAP1128
6.9 Sensor Input Configuration 2 Register
Bits 3 - 0 - M_PRESS[3:0] - (default 0111b) - Determines the minimum amount of time that sensor inputs configured to
use auto repeat must detect a sensor pad touch to detect a “press and hold” event. If the sensor input detects a touch
for longer than the M_PRESS[3:0] settings, a “press and hold” event is detected. If a sensor input detects a touch for
less than or equal to the M_PRESS[3:0] settings, a touch event is detected.
The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-16.
6.10 Averaging and Sampling Configuration Register
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-15: SENSOR INPUT CONFIGURATION 2 REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
23h R/W Sensor Input
Configuration 2 - - - - M_PRESS[3:0] 07h
TABLE 6-16: M_PRESS BIT DECODE
M_PRESS[3:0]
M_PRESS SETTINGS
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms (default)
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-17: AVERAGING AND SAMPLING CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
24h R/W Averaging and
Sampling Config AVG[2:0] SAMP_TIME[1:0] CYCLE_TIME
[1:0] 39h
TABLE 6-14: RPT_RATE BIT DECODE (CONTINUED)
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
CAP1128
DS00001622B-page 40 2015 Microchip Technology Inc.
The Averaging and Sampling Configuration register controls the number of samples taken and the total sensor input
cycle time for all active sensor inputs while the device is functioning in Active state.
Bits 6 - 4 - AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor cycle
as shown in Table 6-18. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
For example, if CS1, CS2, and CS3 are sampled during the sensor cycle, and the AVG[2:0] bits are set to take 4 samples
per channel, then the full sensor cycle will be: CS1, CS1, CS1, CS1, CS2, CS2, CS2, CS2, CS3, CS3, CS3, CS3.
Bits 3 - 2 - SAMP_TIME[1:0] - Determines the time to take a single sample as shown in Table 6-19.
Bits 1 - 0 - CYCLE_TIME[1:0] - Determines the overall cycle time for all measured channels during normal operation as
shown in Table 6-20. All measured channels are sampled at the beginning of the cycle time. If additional time is remaining,
then the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The AVG[2:0] bits will take priority so that if more samples
are required than would normally be allowed during the cycle time, the cycle time will be
extended as necessary to accommodate the number of samples to be measured.
TABLE 6-18: AVG BIT DECODE
AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-19: SAMP_TIME BIT DECODE
SAMP_TIME[1:0]
Sample Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-20: CYCLE_TIME BIT DECODE
CYCLE_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
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CAP1128
6.11 Calibration Activate Register
The Calibration Activate register forces the respective sensor inputs to be re-calibrated affecting both the analog and
digital blocks. During the re-calibration routine, the sensor inputs will not detect a press for up to 600ms and the Sensor
Input Base Count register values will be invalid. During this time, any press on the corresponding sensor pads will invalidate
the re-calibration. When finished, the CALX[9:0] bits will be updated (see Section 6.39).
When the corresponding bit is set, the device will perform the calibration and the bit will be automatically cleared once
the re-calibration routine has finished.
Bit 7 - CS8_CAL - When set, the CS8 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 6 - CS7_CAL - When set, the CS7 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 5 - CS6_CAL - When set, the CS6 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 4 - CS5_CAL - When set, the CS5 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 3 - CS4_CAL - When set, the CS4 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 2 - CS3_CAL - When set, the CS3 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 1 - CS2_CAL - When set, the CS2 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 0 - CS1_CAL - When set, the CS1 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
6.12 Interrupt Enable Register
The Interrupt Enable register determines whether a sensor pad touch or release (if enabled) causes the interrupt pin to
be asserted.
Bit 7 - CS8_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS8 (associated with the CS8
status bit).
• ‘0’ - The interrupt pin will not be asserted if a touch is detected on CS8 (associated with the CS8 status bit).
• ‘1’ (default) - The interrupt pin will be asserted if a touch is detected on CS8 (associated with the CS8 status bit).
Bit 6 - CS7_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS7 (associated with the CS7
status bit).
Bit 5 - CS6_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS6 (associated with the CS6
status bit).
Bit 4 - CS5_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS5 (associated with the CS5
status bit).
Bit 3 - CS4_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS4 (associated with the CS4
status bit).
TABLE 6-21: CALIBRATION ACTIVATE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
26h R/W Calibration
Activate
CS8_
CAL
CS7_
CAL
CS6_
CAL
CS5_
CAL
CS4_
CAL
CS3_
CAL
CS2_
CAL
CS1_
CAL 00h
TABLE 6-22: INTERRUPT ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
27h R/W Interrupt
Enable
CS8_
INT_EN
CS7_
INT_EN
CS6_
INT_EN
CS5_
INT_EN
CS4_
INT_EN
CS3_
INT_EN
CS2_
INT_EN
CS1_
INT_EN FFh
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DS00001622B-page 42 2015 Microchip Technology Inc.
Bit 2 - CS3_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS3 (associated with the CS3
status bit).
Bit 1 - CS2_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS2 (associated with the CS2
status bit).
Bit 0 - CS1_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS1 (associated with the CS1
status bit).
6.13 Repeat Rate Enable Register
The Repeat Rate Enable register enables the repeat rate of the sensor inputs as described in Section 5.6.1.
Bit 7 - CS8_RPT_EN - Enables the repeat rate for capacitive touch sensor input 8.
• ‘0’ - The repeat rate for CS8 is disabled. It will only generate an interrupt when a touch is detected and when a
release is detected (if enabled) no matter how long the touch is held for.
• ‘1’ (default) - The repeat rate for CS8 is enabled. In the case of a “touch” event, it will generate an interrupt when a
touch is detected and a release is detected (as determined by the INT_REL_n bit - see Section 6.6). In the case of
a “press and hold” event, it will generate an interrupt when a touch is detected and at the repeat rate so long as
the touch is held.
Bit 6 - CS7_RPT_EN - Enables the repeat rate for capacitive touch sensor input 7.
Bit 5 - CS6_RPT_EN - Enables the repeat rate for capacitive touch sensor input 6.
Bit 4 - CS5_RPT_EN - Enables the repeat rate for capacitive touch sensor input 5.
Bit 3 - CS4_RPT_EN - Enables the repeat rate for capacitive touch sensor input 4.
Bit 2 - CS3_RPT_EN - Enables the repeat rate for capacitive touch sensor input 3.
Bit 1 - CS2_RPT_EN - Enables the repeat rate for capacitive touch sensor input 2.
Bit 0 - CS1_RPT_EN - Enables the repeat rate for capacitive touch sensor input 1.
6.14 Multiple Touch Configuration Register
The Multiple Touch Configuration register controls the settings for the multiple touch detection circuitry. These settings
determine the number of simultaneous buttons that may be pressed before additional buttons are blocked and the MULT
status bit is set.
Bit 7 - MULT_BLK_EN - Enables the multiple button blocking circuitry.
• ‘0’ - The multiple touch circuitry is disabled. The device will not block multiple touches.
• ‘1’ (default) - The multiple touch circuitry is enabled. The device will flag the number of touches equal to programmed
multiple touch threshold and block all others. It will remember which sensor inputs are valid and block all
others until that sensor pad has been released. Once a sensor pad has been released, the N detected touches
(determined via the cycle order of CS1 - CS8) will be flagged and all others blocked.
Bits 3 - 2 - B_MULT_T[1:0] - Determines the number of simultaneous touches on all sensor pads before a Multiple Touch
Event is detected and sensor inputs are blocked. The bit decode is given by Table 6-25.
TABLE 6-23: REPEAT RATE ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
28h R/W Repeat Rate
Enable
CS8_
RPT_EN
CS7_
RPT_EN
CS6_
RPT_EN
CS5_
RPT_EN
CS4_
RPT_EN
CS3_
RPT_EN
CS2_
RPT_EN
CS1_
RPT_EN FFh
TABLE 6-24: MULTIPLE TOUCH CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Ah R/W Multiple Touch
Config
MULT_
BLK_
EN
- - - B_MULT_T[1:0] - - 80h
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6.15 Multiple Touch Pattern Configuration Register
The Multiple Touch Pattern Configuration register controls the settings for the multiple touch pattern detection circuitry.
This circuitry works like the multiple touch detection circuitry with the following differences:
1. The detection threshold is a percentage of the touch detection threshold as defined by the MTP_TH[1:0] bits
whereas the multiple touch circuitry uses the touch detection threshold.
2. The MTP detection circuitry either will detect a specific pattern of sensor inputs as determined by the Multiple
Touch Pattern register settings or it will use the Multiple Touch Pattern register settings to determine a minimum
number of sensor inputs that will cause the MTP circuitry to flag an event. When using pattern recognition mode,
if all of the sensor inputs set by the Multiple Touch Pattern register have a delta count greater than the MTP
threshold or have their corresponding Noise Flag Status bits set, the MTP bit will be set. When using the absolute
number mode, if the number of sensor inputs with thresholds above the MTP threshold or with Noise Flag Status
bits set is equal to or greater than this number, the MTP bit will be set.
3. When an MTP event occurs, all touches are blocked and an interrupt is generated.
4. All sensor inputs will remain blocked so long as the requisite number of sensor inputs are above the MTP threshold
or have Noise Flag Status bits set. Once this condition is removed, touch detection will be restored. Note that
the MTP status bit is only cleared by writing a ‘0’ to the INT bit once the condition has been removed.
Bit 7 - MTP_EN - Enables the multiple touch pattern detection circuitry.
• ‘0’ (default) - The MTP detection circuitry is disabled.
• ‘1’ - The MTP detection circuitry is enabled.
Bits 3-2 - MTP_TH[1:0] - Determine the MTP threshold, as shown in Table 6-27. This threshold is a percentage of sensor
input threshold (see Section 6.18, "Sensor Input Threshold Registers") when the device is in the Fully Active state or of
the standby threshold (see Section 6.23, "Standby Threshold Register") when the device is in the Standby state.
Bit 1 - COMP_PTRN - Determines whether the MTP detection circuitry will use the Multiple Touch Pattern register as a
specific pattern of sensor inputs or as an absolute number of sensor inputs.
• ‘0’ (default) - The MTP detection circuitry will use the Multiple Touch Pattern register bit settings as an absolute
minimum number of sensor inputs that must be above the threshold or have Noise Flag Status bits set. The number
will be equal to the number of bits set in the register.
TABLE 6-25: B_MULT_T BIT DECODE
B_MULT_T[1:0]
Number of Simultaneous Touches
1 0
0 0 1 (default)
01 2
10 3
11 4
TABLE 6-26: MULTIPLE TOUCH PATTERN CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Bh R/W Multiple Touch
Pattern Config MTP_ EN - - MTP_TH[1:0] COMP_
PTRN
MTP_
ALERT 00h
TABLE 6-27: MTP_TH BIT DECODE
MTP_TH[1:0]
Threshold Divide Setting
1 0
0 0 12.5% (default)
0 1 25%
1 0 37.5%
1 1 100%
CAP1128
DS00001622B-page 44 2015 Microchip Technology Inc.
• ‘1’ - The MTP detection circuitry will use pattern recognition. Each bit set in the Multiple Touch Pattern register
indicates a specific sensor input that must have a delta count greater than the MTP threshold or have a Noise Flag
Status bit set. If the criteria are met, the MTP status bit will be set.
Bit 0 - MTP_ALERT - Enables an interrupt if an MTP event occurs. In either condition, the MTP status bit will be set.
• ‘0’ (default) - If an MTP event occurs, the ALERT# pin is not asserted.
• ‘1’ - If an MTP event occurs, the ALERT# pin will be asserted.
6.16 Multiple Touch Pattern Register
The Multiple Touch Pattern register acts as a pattern to identify an expected sensor input profile for diagnostics or other
significant events. There are two methods for how the Multiple Touch Pattern register is used: as specific sensor inputs
or number of sensor input that must exceed the MTP threshold or have Noise Flag Status bits set. Which method is used
is based on the COMP_PTRN bit (see Section 6.15). The methods are described below.
1. Specific Sensor Inputs: If, during a single polling cycle, the specific sensor inputs above the MTP threshold or
with Noise Flag Status bits set match those bits set in the Multiple Touch Pattern register, an MTP event is
flagged.
2. Number of Sensor Inputs: If, during a single polling cycle, the number of sensor inputs with a delta count above
the MTP threshold or with Noise Flag Status bits set is equal to or greater than the number of pattern bits set, an
MTP event is flagged.
Bit 7 - CS8_PTRN - Determines whether CS8 is considered as part of the Multiple Touch Pattern.
• ‘0’ - CS8 is not considered a part of the pattern.
• ‘1’ - CS8 is considered a part of the pattern, or the absolute number of sensor inputs that must have a delta count
greater than the MTP threshold or have the Noise Flag Status bit set is increased by 1.
Bit 6 - CS7_PTRN - Determines whether CS7 is considered as part of the Multiple Touch Pattern.
Bit 5 - CS6_PTRN - Determines whether CS6 is considered as part of the Multiple Touch Pattern.
Bit 4 - CS5_PTRN - Determines whether CS5 is considered as part of the Multiple Touch Pattern.
Bit 3 - CS4_PTRN - Determines whether CS4 is considered as part of the Multiple Touch Pattern.
Bit 2 - CS3_PTRN - Determines whether CS3 is considered as part of the Multiple Touch Pattern.
Bit 1 - CS2_PTRN - Determines whether CS2 is considered as part of the Multiple Touch Pattern.
Bit 0 - CS1_PTRN - Determines whether CS1 is considered as part of the Multiple Touch Pattern.
6.17 Recalibration Configuration Register
The Recalibration Configuration register controls the automatic re-calibration routine settings as well as advanced controls
to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor Input 1 Threshold
register.
• ‘0’ - Each Sensor Input X Threshold register is updated individually.
• ‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor Input Threshold
registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input Threshold 8). The individual Sensor
TABLE 6-28: MULTIPLE TOUCH PATTERN REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Dh R/W Multiple
Touch Pattern
CS8_
PTRN
CS7_
PTRN
CS6_
PTRN
CS5_
PTRN
CS4_
PTRN
CS3_
PTRN
CS2_
PTRN
CS1_
PTRN FFh
TABLE 6-29: RECALIBRATION CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Fh R/W Recalibration
Configuration
BUT_
LD_TH
NO_
CLR_
INTD
NO_
CLR_
NEG
NEG_DELTA_
CNT[1:0] CAL_CFG[2:0] 8Ah
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Input X Threshold registers (Sensor Input 2 Threshold through Sensor Input 8 Threshold) can be individually
updated at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise status bit is set.
• ‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
• ‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if the noise status bit
is set.
• ‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
• ‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to trigger a digital recalibration
as shown in Table 6-30.
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-calibration routine.
The settings apply to all sensor inputs universally (though individual sensor inputs can be configured to support re-calibration
- see Section 6.11).
Note 6-1 Recalibration Samples refers to the number of samples that are measured and averaged before the
Base Count is updated however does not control the base count update period.
Note 6-2 Update Time refers to the amount of time (in polling cycle periods) that elapses before the Base
Count is updated. The time will depend upon the number of channels active, the averaging setting,
and the programmed cycle time.
TABLE 6-30: NEG_DELTA_CNT BIT DECODE
NEG_DELTA_CNT[1:0]
Number of Consecutive Negative Delta Count Values
1 0
00 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
TABLE 6-31: CAL_CFG BIT DECODE
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
0 0 0 16 16
0 0 1 32 32
0 1 0 64 64 (default)
0 1 1 128 128
1 0 0 256 256
1 0 1 256 1024
1 1 0 256 2048
1 1 1 256 4096
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DS00001622B-page 46 2015 Microchip Technology Inc.
6.18 Sensor Input Threshold Registers
The Sensor Input Threshold registers store the delta threshold that is used to determine if a touch has been detected.
When a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with
a touch. If the sensor input change exceeds the threshold settings, a touch is detected.
When the BUT_LD_TH bit is set (see Section 6.17 - bit 7), writing data to the Sensor Input 1 Threshold register will
update all of the sensor input threshold registers (31h - 37h inclusive).
6.19 Sensor Input Noise Threshold Register
The Sensor Input Noise Threshold register controls the value of a secondary internal threshold to detect noise and
improve the automatic recalibration routine. If a capacitive touch sensor input exceeds the Sensor Input Noise Threshold
but does not exceed the sensor input threshold, it is determined to be caused by a noise spike. That sample is not used
by the automatic re-calibration routine. This feature can be disabled by setting the DIS_DIG_NOISE bit.
Bits 1-0 - CS1_BN_TH[1:0] - Controls the noise threshold for all capacitive touch sensor inputs, as shown in Table 6-34.
The threshold is proportional to the threshold setting.
TABLE 6-32: SENSOR INPUT THRESHOLD REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
30h R/W Sensor Input 1
Threshold - 64 32 16 8 4 2 1 40h
31h R/W Sensor Input 2
Threshold - 64 32 16 8 4 2 1 40h
32h R/W Sensor Input 3
Threshold - 64 32 16 8 4 2 1 40h
33h R/W Sensor Input 4
Threshold - 64 32 16 8 4 2 1 40h
34h R/W Sensor Input 5
Threshold - 64 32 16 8 4 2 1 40h
35h R/W Sensor Input 6
Threshold - 64 32 16 8 4 2 1 40h
36h R/W Sensor Input 7
Threshold - 64 32 16 8 4 2 1 40h
37h R/W Sensor Input 8
Threshold - 64 32 16 8 4 2 1 40h
TABLE 6-33: SENSOR INPUT NOISE THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
38h R/W Sensor Input
Noise Threshold CS_BN_TH [1:0] 01h
TABLE 6-34: CSX_BN_TH BIT DECODE
CS_BN_TH[1:0]
Percent Threshold Setting
1 0
0 0 25%
0 1 37.5% (default)
1 0 50%
1 1 62.5%
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6.20 Standby Channel Register
The Standby Channel register controls which (if any) capacitive touch sensor inputs are active during Standby.
Bit 7 - CS8_STBY - Controls whether the CS8 channel is active in Standby.
• ‘0’ (default) - The CS8 channel not be sampled during Standby.
• ‘1’ - The CS8 channel will be sampled during Standby. It will use the Standby threshold setting, and the standby
averaging and sensitivity settings.
Bit 6 - CS7_STBY - Controls whether the CS7 channel is active in Standby.
Bit 5 - CS6_STBY - Controls whether the CS6 channel is active in Standby.
Bit 4 - CS5_STBY - Controls whether the CS5 channel is active in Standby.
Bit 3 - CS4_STBY - Controls whether the CS4 channel is active in Standby.
Bit 2 - CS3_STBY - Controls whether the CS3 channel is active in Standby.
Bit 1 - CS2_STBY - Controls whether the CS2 channel is active in Standby.
Bit 0 - CS1_STBY - Controls whether the CS1 channel is active in Standby.
6.21 Standby Configuration Register
The Standby Configuration register controls averaging and cycle time for those sensor inputs that are active in Standby.
This register is useful for detecting proximity on a small number of sensor inputs as it allows the user to change averaging
and sample times on a limited number of sensor inputs and still maintain normal functionality in the fully active
state.
Bit 7 - AVG_SUM - Determines whether the active sensor inputs will average the programmed number of samples or
whether they will accumulate for the programmed number of samples.
• ‘0’ - (default) - The active sensor input delta count values will be based on the average of the programmed number
of samples when compared against the threshold.
• ‘1’ - The active sensor input delta count values will be based on the summation of the programmed number of
samples when compared against the threshold. This bit should only be set when performing proximity detection as
a physical touch will overflow the delta count registers and may result in false readings.
Bits 6 - 4 - STBY_AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor
cycle as shown in Table 6-37. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
TABLE 6-35: STANDBY CHANNEL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
40h R/W Standby Channel CS8_
STBY
CS7_
STBY
CS6_
STBY
CS5_
STBY
CS4_
STBY
CS3_
STBY
CS2_
STBY
CS1_
STBY 00h
TABLE 6-36: STANDBY CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
41h R/W Standby Configuration
AVG_
SUM STBY_AVG[2:0] STBY_SAMP_
TIME[1:0]
STBY_CY_TIME
[1:0] 39h
TABLE 6-37: STBY_AVG BIT DECODE
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
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DS00001622B-page 48 2015 Microchip Technology Inc.
Bit 3-2 - STBY SAMP_TIME[1:0] - Determines the time to take a single sample when the device is in Standby as shown
in Table 6-38.
Bits 1 - 0 - STBY_CY_TIME[2:0] - Determines the overall cycle time for all measured channels during standby operation
as shown in Table 6-39. All measured channels are sampled at the beginning of the cycle time. If additional time is
remaining, the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The STBY_AVG[2:0] bits will take priority so that if more
samples are required than would normally be allowed during the cycle time, the cycle time
will be extended as necessary to accommodate the number of samples to be measured.
6.22 Standby Sensitivity Register
The Standby Sensitivity register controls the sensitivity for sensor inputs that are active in Standby.
Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensor inputs that are active in Standby. The sensitivity settings
act to scale the relative delta count value higher or lower based on the system parameters. A setting of 000b is the
most sensitive while a setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a
smaller delta C corresponding to a “lighter” touch. These settings are more sensitive to noise however and a noisy environment
may flag more false touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-38: STBY_SAMP_TIME BIT DECODE
STBY_SAMP_TIME[1:0]
Sampling Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-39: STBY_CY_TIME BIT DECODE
STBY_CY_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-40: STANDBY SENSITIVITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
42h R/W Standby Sensitivity
- - - - - STBY_SENSE[2:0] 02h
TABLE 6-37: STBY_AVG BIT DECODE (CONTINUED)
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
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CAP1128
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
6.23 Standby Threshold Register
The Standby Threshold register stores the delta threshold that is used to determine if a touch has been detected. When
a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with a
touch. If the sensor input change exceeds the threshold settings, a touch is detected.
6.24 Sensor Input Base Count Registers
The Sensor Input Base Count registers store the calibrated “Not Touched” input value from the capacitive touch sensor
inputs. These registers are periodically updated by the re-calibration routine.
TABLE 6-41: STBY_SENSE BIT DECODE
STBY_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-42: STANDBY THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
43h R/W Standby Threshold
- 64 32 16 8 4 2 1 40h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
50h R Sensor Input 1
Base Count 128 64 32 16 8 4 2 1 C8h
51h R Sensor Input 2
Base Count 128 64 32 16 8 4 2 1 C8h
52h R Sensor Input 3
Base Count 128 64 32 16 8 4 2 1 C8h
53h R Sensor Input 4
Base Count 128 64 32 16 8 4 2 1 C8h
54h R Sensor Input 5
Base Count 128 64 32 16 8 4 2 1 C8h
55h R Sensor Input 6
Base Count 128 64 32 16 8 4 2 1 C8h
56h R Sensor Input 7
Base Count 128 64 32 16 8 4 2 1 C8h
57h R Sensor Input 8
Base Count 128 64 32 16 8 4 2 1 C8h
CAP1128
DS00001622B-page 50 2015 Microchip Technology Inc.
The routine uses an internal adder to add the current count value for each reading to the sum of the previous readings
until sample size has been reached. At this point, the upper 16 bits are taken and used as the Sensor Input Base Count.
The internal adder is then reset and the re-calibration routine continues.
The data presented is determined by the BASE_SHIFT[3:0] bits (see Section 6.5).
6.25 LED Output Type Register
The LED Output Type register controls the type of output for the LED pins. Each pin is controlled by a single bit. Refer
to application note 21.4 CAP1128Family LED Configuration Options for more information about implementing LEDs.
Bit 1 - LED2_OT - Determines the output type of the LED2 pin.
• ‘0’ (default) - The LED2 pin is an open-drain output with an external pull-up resistor. When the appropriate pin is
set to the “active” state (logic ‘1’), the pin will be driven low. Conversely, when the pin is set to the “inactive” state
(logic ‘0’), then the pin will be left in a High Z state and pulled high via an external pull-up resistor.
• ‘1’ - The LED2 pin is a push-pull output. When driving a logic ‘1’, the pin is driven high. When driving a logic ‘0’, the
pin is driven low.
Bit 0 - LED1_OT - Determines the output type of the LED1 pin.
6.26 Sensor Input LED Linking Register
The Sensor Input LED Linking register controls whether a capacitive touch sensor input is linked to an LED output. If
the corresponding bit is set, then the appropriate LED output will change states defined by the LED Behavior controls
(see Section 6.31) in response to the capacitive touch sensor input.
Bit 1 - CS2_LED2 - Links the LED2 output to a detected touch on the CS2 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
• ‘0’ (default) - The LED 2 output is not associated with the CS2 input. If a touch is detected on the CS2 input, the
LED will not automatically be actuated. The LED is enabled and controlled via the LED Output Control register
(see Section 6.28) and the LED Behavior registers (see Section 6.31).
• ‘1’ - The LED 2 output is associated with the CS2 input. If a touch is detected on the CS2 input, the LED will be
actuated and behave as defined in Table 6-52.
Bit 0 - CS1_LED1 - Links the LED1 output to a detected touch on the CS1 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
6.27 LED Polarity Register
The LED Polarity register controls the logical polarity of the LED outputs. When these bits are set or cleared, the corresponding
LED Mirror controls are also set or cleared (unless the BLK_POL_MIR bit is set - see Section 6.6, "Configuration
Registers"). Table 6-48, "LED Polarity Behavior" shows the interaction between the polarity controls, output
controls, and relative brightness.
TABLE 6-44: LED OUTPUT TYPE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
71h R/W LED Output
Type ----- - LED2_
OT
LED1_
OT 00h
TABLE 6-45: SENSOR INPUT LED LINKING REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
72h R/W Sensor Input
LED Linking
- - - - - - CS2_
LED2
CS1_
LED1
00h
TABLE 6-46: LED POLARITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
73h R/W LED Polarity - - - - - - LED2_
POL
LED1_
POL 00h
2015 Microchip Technology Inc. DS00001622B-page 51
CAP1128
APPLICATION NOTE: The polarity controls determine the final LED pin drive. A touch on a linked capacitive touch
sensor input is treated in the same way as the LED Output Control bit being set to a logic ‘1’.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’ then the LED will be on and that the CAP1128 LED pin is sinking the LED current.
Conversely, if the LED pin is driven to a logic ‘1’, the LED will be off and there is no current
flow. See Figure 5-1, "System Diagram for CAP1128".
APPLICATION NOTE: This application note applies when the LED polarity is inverted (LEDx_POL = ‘0’). For LED
operation, the duty cycle settings determine the % of time that the LED pin will be driven to
a logic ‘0’ state in. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven low (i.e. maximum % of time that the LED is on) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven low (i.e. minimum
% of time that the LED is on). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at the minimum duty cycle setting.
Breathe operations will ramp the duty cycle from the minimum duty cycle to the maximum
duty cycle.
APPLICATION NOTE: This application note applies when the LED polarity is non-inverted (LEDx_POL = ‘1’). For
LED operation, the duty cycle settings determine the % of time that the LED pin will be driven
to a logic ‘1’ state. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven high (i.e. maximum % of time that the LED is off) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven high (i.e. minimum
% of time that the LED is off). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at 100 minus the minimum duty
cycle setting. Breathe operations will ramp the duty cycle from 100 minus the minimum duty
cycle to 100 minus the maximum duty cycle.
APPLICATION NOTE: The LED Mirror controls (see Section 6.30, "LED Mirror Control Register") work with the
polarity controls with respect to LED brightness but will not have a direct effect on the output
pin drive.
Bit 1 - LED2_POL - Determines the polarity of the LED2 output.
• ‘0’ (default) - The LED2 output is inverted. For example, a setting of ‘1’ in the LED Output Control register will
cause the LED pin output to be driven to a logic ‘0’.
• ‘1’ - The LED2 output is non-inverted. For example, a setting of ‘1’ in the LED Output Control register will cause
the LED pin output to be driven to a logic ‘1’ or left in the high-z state as determined by its output type.
Bit 0 - LED1_POL - Determines the polarity of the LED1 output.
6.28 LED Output Control Register
The LED Output Control Register controls the output state of the LED pins that are not linked to sensor inputs.
The LED Polarity Control Register will determine the non actuated state of the LED pins. The actuated LED behavior is
determined by the LED behavior controls (see Section 6.31, "LED Behavior Register").
TABLE 6-47: LED OUTPUT CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
74h R/W LED Output
Control --- - -- LED2_
DR
LED1_
DR 00h
Note: If an LED is linked to a sensor input in the Sensor Input LED Linking Register (Section 6.26, "Sensor Input
LED Linking Register"), the corresponding bit in the LED Output Control Register is ignored (i.e. a linked
LED cannot be host controlled).
CAP1128
DS00001622B-page 52 2015 Microchip Technology Inc.
Table 6-48 shows the interaction between the polarity controls, output controls, and relative brightness.
Bit 1 - LED2_DR - Determines whether LED2 output is driven high or low.
• ‘0’ (default) - The LED2 output is driven at the minimum duty cycle or not actuated.
• ‘1’ - The LED2 output is High Z or driven at the maximum duty cycle or actuated.
Bit 0 - LED1_DR - Determines whether LED1 output is driven high or low.
6.29 Linked LED Transition Control Register
The Linked LED Transition Control register controls the LED drive when the LED is linked to a capacitive touch sensor
input. These controls work in conjunction with the INV_LINK_TRAN bit (see Section 6.6.2, "Configuration 2 - 44h") to
create smooth transitions from host control to linked LEDs.
Bit 1 - LED2_LTRAN - Determines the transition effect when LED2 is linked to CS2.
• ‘0’ (default) - When the LED output control bit for LED2 is ‘1’, and then LED2 is linked to CS2 and no touch is
detected, the LED will change states.
• ‘1’ - If the INV_LINK_TRAN bit is ‘1’, when the LED output control bit for CS2 is ‘1’, and then CS2 is linked to LED2
and no touch is detected, the LED will not change states. In addition, the LED state will change when the sensor
pad is touched. If the INV_LINK_TRAN bit is ‘0’, when the LED output control bit for CS2 is ‘1’, and then CS2 is
linked to LED2 and no touch is detected, the LED will not change states. However, the LED state will not change
when the sensor pad is touched.
APPLICATION NOTE: If the LED behavior is not “Direct” and the INV_LINK_TRAN bit it ‘0’, the LED will not perform
as expected when the LED2_LTRAN bit is set to ‘1’. Therefore, if breathe and pulse
behaviors are used, set the INV_LINK_TRAN bit to ‘1’.
TABLE 6-48: LED POLARITY BEHAVIOR
LED Output
Control
Register or
Touch
Polarity Max Duty Min Duty Brightness LED Appearance
0 inverted (‘0’) not used
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
min duty cycle
on at min duty
cycle
1 inverted (‘0’)
maximum % of time
that the LED is on
(logic 0)
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
max duty cycle. Brightness
ramps from min
duty cycle to max duty
cycle
according to LED
behavior
0 non-inverted
(‘1’) not used
minimum % of time
that the LED is off
(logic 1)
maximum brightness at
100 minus min duty
cycle.
on at 100 - min
duty cycle
1 non-inverted
(‘1’)
maximum % of time
that the LED is off
(logic 1)
minimum % of time
that the LED is off
(logic 1)
For Direct behavior,
maximum brightness is
100 minus max duty
cycle. When breathing,
max brightness is
100 minus min duty
cycle. Brightness
ramps from 100 - min
duty cycle to 100 - max
duty cycle.
according to LED
behavior
TABLE 6-49: LINKED LED TRANSITION CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
77h R/W Linked LED Transition
Control - ----- LED2_
LTRAN
LED1_
LTRAN 00h
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CAP1128
Bit 0 - LED1_LTRAN - Determines the transition effect when LED1 is linked to CS1.
6.30 LED Mirror Control Register
The LED Mirror Control Registers determine the meaning of duty cycle settings when polarity is non-inverted for each
LED channel. When the polarity bit is set to ‘1’ (non-inverted), to obtain correct steps for LED ramping, pulse, and
breathe behaviors, the min and max duty cycles need to be relative to 100%, rather than the default, which is relative
to 0%.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’, the LED will be on and the CAP1128 LED pin is sinking the LED current. When
the polarity bit is set to ‘1’, it is considered non-inverted. For systems using the opposite LED
configuration, mirror controls would apply when the polarity bit is ‘0’.
These bits are changed automatically if the corresponding LED Polarity bit is changed (unless the BLK_POL_MIR bit is
set - see Section 6.6).
Bit 1 - LED2_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
• ‘0’ (default) - The duty cycle settings are determined relative to 0% and are determined directly with the settings.
• ‘1’ - The duty cycle settings are determined relative to 100%.
Bit 0 - LED1_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
6.31 LED Behavior Register
The LED Behavior register controls the operation of LEDs. Each LED pin is controlled by a 2-bit field and the behavior
is determined by whether the LED is linked to a capacitive touch sensor input or not.
If the corresponding LED output is linked to a capacitive touch sensor input, the appropriate behavior will be enabled /
disabled based on touches and releases.
If the LED output is not associated with a capacitive touch sensor input, the appropriate behavior will be enabled / disabled
by the LED Output Control register. If the respective LEDx_DR bit is set to a logic ‘1’, this will be associated as a
“touch”, and if the LEDx_DR bit is set to a logic ‘0’, this will be associated as a “release”.
Table 6-52, "LEDx_CTL Bit Decode" shows the behavior triggers. The defined behavior will activate when the Start Trigger
is met and will stop when the Stop Trigger is met. Note the behavior of the Breathe Hold and Pulse Release option.
The LED Polarity Control register will determine the non actuated state of the LED outputs (see Section 6.27, "LED
Polarity Register").
APPLICATION NOTE: If an LED is not linked to a capacitive touch sensor input and is breathing (via the Breathe
or Pulse behaviors), it must be unactuated and then re-actuated before changes to behavior
are processed. For example, if the LED output is breathing and the Maximum duty cycle is
changed, this change will not take effect until the LED output control register is set to ‘0’ and
then re-set to ‘1’.
APPLICATION NOTE: If an LED is not linked to the capacitive touch sensor input and configured to operate using
Pulse 1 Behavior, then the circuitry will only be actuated when the corresponding output
control bit is set. It will not check the bit condition until the Pulse 1 behavior is finished. The
device will not remember if the bit was cleared and reset while it was actuated.
TABLE 6-50: LED MIRROR CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
79h R/W LED Mirror Control
------
LED2_
MIR _
EN
LED1_
MIR _
EN
00h
TABLE 6-51: LED BEHAVIOR REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
81h R/W LED Behavior 1 - - - - LED2_CTL[1:0] LED1_CTL[1:0] 00h
CAP1128
DS00001622B-page 54 2015 Microchip Technology Inc.
APPLICATION NOTE: If an LED is actuated and not linked and the desired LED behavior is changed, this new
behavior will take effect immediately; however, the first instance of the changed behavior
may act incorrectly (e.g. if changed from Direct to Pulse 1, the LED output may ‘breathe’ 4
times and then end at minimum duty cycle). LED Behaviors will operate normally once the
LED has been un-actuated and then re-actuated.
APPLICATION NOTE: If an LED is actuated and it is switched from linked to a capacitive touch sensor input to
unlinked (or vice versa), the LED will respond to the new command source immediately if
the behavior was Direct or Breathe. For Pulse behaviors, it will complete the behavior
already in progress. For example, if a linked LED was actuated by a touch and the control
is changed so that it is unlinked, it will check the status of the corresponding LED Output
Control bit. If that bit is ‘0’, then the LED will behave as if a release was detected. Likewise,
if an unlinked LED was actuated by the LED Output Control register and the control is
changed so that it is linked and no touch is detected, then the LED will behave as if a release
was detected.
Bits 3 - 2 - LED2_CTL[1:0] - Determines the behavior of LED2 as shown in Table 6-52.
Bits 1 - 0 - LED1_CTL[1:0] - Determines the behavior of LED1 as shown in Table 6-52.
APPLICATION NOTE: The PWM frequency is determined based on the selected LED behavior, the programmed
breathe period, and the programmed min and max duty cycles. For the Direct behavior
mode, the PWM frequency is calculated based on the programmed Rise and Fall times. If
these are set at 0, then the maximum PWM frequency will be used based on the
programmed duty cycle settings.
TABLE 6-52: LEDX_CTL BIT DECODE
LEDx_CTL
[1:0] Operation Description Start TRigger Stop Trigger
1 0
0 0 Direct The LED is driven to the programmed state
(active or inactive). See Figure 6-7
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
0 1 Pulse 1
The LED will “Pulse” a programmed number
of times. During each “Pulse” the LED will
breathe up to the maximum brightness and
back down to the minimum brightness so that
the total “Pulse” period matches the programmed
value.
Touch or Release
Detected or LED
Output Control bit
set or cleared
(see Section 6.32)
n/a
1 0 Pulse 2
The LED will “Pulse” when the start trigger is
detected. When the stop trigger is detected, it
will “Pulse” a programmable number of times
then return to its minimum brightness.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
1 1 Breathe
The LED will breathe. It will be driven with a
duty cycle that ramps up from the programmed
minimum duty cycle (default 0%) to
the programmed maximum duty cycle duty
cycle (default 100%) and then back down.
Each ramp takes up 50% of the programmed
period. The total period of each “breath” is
determined by the LED Breathe Period controls
- see Section 6.34.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
2015 Microchip Technology Inc. DS00001622B-page 55
CAP1128
6.32 LED Pulse 1 Period Register
The LED Pulse Period 1 register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 01b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms (24 x 32ms = 768ms). The total range is from 32ms to 4.064 seconds as shown in Table 6-54 with the
default being 1024ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
Bit 7 - ST_TRIG - Determines the start trigger for the LED Pulse behavior.
• ‘0’ (default) - The LED will Pulse when a touch is detected or the drive bit is set.
• ‘1’ - The LED will Pulse when a release is detected or the drive bit is cleared.
The Pulse 1 operation is shown in Figure 6-1 when the LED output is configured for non-inverted polarity (LEDx_POL
= 1) and in Figure 6-2 for inverted polarity (LEDx_POL = 0).
.
TABLE 6-53: LED PULSE 1 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
84h R/W LED Pulse 1
Period
ST_
TRIG
P1_
PER6
P1_
PER5
P1_
PER4
P1_
PER3
P1_
PER2
P1_
PER1
P1_
PER0 20h
FIGURE 6-1: Pulse 1 Behavior with Non-Inverted Polarity
Normal – untouched
operation Normal – untouched
operation
Touch Detected or
Release Detected
(100% - Pulse 1 Max Duty Cycle) * Brightness
X pulses after touch or after release
Pulse 1 Period
(P1_PER)
(100% - Pulse 1 Min Duty Cycle) * Brightness
LED
Brightness
CAP1128
DS00001622B-page 56 2015 Microchip Technology Inc.
6.33 LED Pulse 2 Period Register
The LED Pulse 2 Period register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 10b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 640ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
The Pulse 2 Behavior is shown in Figure 6-3 for non-inverted polarity (LEDx_POL = 1) and in Figure 6-4 for inverted
polarity (LEDx_POL = 0).
FIGURE 6-2: Pulse 1 Behavior with Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
00h 0 32
01h 1 32
02h 2 64
03h 3 96
. . . . . . . . .
7Dh 125 4000
7Eh 126 4032
7Fh 127 4064
TABLE 6-55: LED PULSE 2 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
85h R/W LED Pulse 2
Period - P2_
PER6
P2_
PER5
P2_
PER4
P2_
PER3
P2_
PER2
P2_
PER1
P2_
PER0 14h
Normal – untouched
operation
Normal – untouched
operation
Touch Detected or
Release Detected
Pulse 1 Min Duty Cycle * Brightness
X pulses after touch or after release
Pulse Period
(P1_PER)
Pulse 1 Max Duty Cycle * Brightness
LED
Brightness
2015 Microchip Technology Inc. DS00001622B-page 57
CAP1128
6.34 LED Breathe Period Register
The LED Breathe Period register determines the overall period of a breathe operation as determined by the LED_CTL
registers (see Table 6-52 - setting 11b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 2976ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
FIGURE 6-3: Pulse 2 Behavior with Non-Inverted Polarity
FIGURE 6-4: Pulse 2 Behavior with Inverted Polarity
TABLE 6-56: LED BREATHE PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
86h R/W LED Breathe
Period - BR_
PER6
BR_
PER5
BR_
PER4
BR_
PER3
BR_
PER2
BR_
PER1
BR_
PER0 5Dh
. . .
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
(100% - Pulse 2 Min Duty Cycle) *
Brightness
(100% - Pulse 2 Max Duty Cycle) * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
Pulse 2 Max Duty Cycle * Brightness
Pulse 2 Min Duty Cycle * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness . . .
CAP1128
DS00001622B-page 58 2015 Microchip Technology Inc.
6.35 LED Configuration Register
The LED Configuration register controls general LED behavior as well as the number of pulses that are sent for the
PULSE LED output behavior.
Bit 6 - RAMP_ALERT - Determines whether the device will assert the ALERT# pin when LEDs actuated by the LED
Output Control register bits have finished their respective behaviors. Interrupts will only be generated if the LED activity
is generated by writing the LED Output Control registers. Any LED activity associated with touch detection will not cause
an interrupt to be generated when the LED behavior has been finished.
• ‘0’ (default) - The ALERT# pin will not be asserted when LEDs actuated by the LED Output Control register have
finished their programmed behaviors.
• ‘1’ - The ALERT# pin will be asserted whenever any LED that is actuated by the LED Output Control register has
finished its programmed behavior.
Bits 5 - 3 - PULSE2_CNT[2:0] - Determines the number of pulses used for the Pulse 2 behavior as shown in Table 6-58.
Bits 2 - 0 - PULSE1_CNT[2:0] - Determines the number of pulses used for the Pulse 1 behavior as shown in Table 6-58.
6.36 LED Duty Cycle Registers
The LED Duty Cycle registers determine the minimum and maximum duty cycle settings used for the LED for each LED
behavior. These settings affect the brightness of the LED when it is fully off and fully on.
The LED driver duty cycle will ramp up from the minimum duty cycle to the maximum duty cycle and back down again.
APPLICATION NOTE: When operating in Direct behavior mode, changes to the Duty Cycle settings will be applied
immediately. When operating in Breathe, Pulse 1, or Pulse 2 modes, the LED must be
unactuated and then re-actuated before changes to behavior are processed.
TABLE 6-57: LED CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
88h R/W LED Config - RAMP_
ALERT PULSE2_CNT[2:0] PULSE1_CNT[2:0] 04h
TABLE 6-58: PULSEX_CNT DECODE
PULSEX_CNT[2:0]
Number of Breaths
21 0
0 0 0 1 (default - Pulse 2)
00 1 2
01 0 3
01 1 4
1 0 0 5 (default - Pulse 1)
10 1 6
11 0 7
11 1 8
TABLE 6-59: LED DUTY CYCLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
90h R/W LED Pulse 1 Duty
Cycle P1_MAX_DUTY[3:0] P1_MIN_DUTY[3:0] F0h
91h R/W LED Pulse 2 Duty
Cycle P2_MAX_DUTY[3:0] P2_MIN_DUTY[3:0] F0h
92h R/W LED Breathe
Duty Cycle BR_MAX_DUTY[3:0] BR_MIN_DUTY[3:0] F0h
93h R/W Direct Duty Cycle DR_MAX_DUTY[3:0] DR_MIN_DUTY[3:0] F0h
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Bits 7 - 4 - X_MAX_DUTY[3:0] - Determines the maximum PWM duty cycle for the LED drivers as shown in Table 6-60.
Bits 3 - 0 - X_MIN_DUTY[3:0] - Determines the minimum PWM duty cycle for the LED drivers as shown in Table 6-60.
6.37 LED Direct Ramp Rates Register
The LED Direct Ramp Rates register control the rising and falling edge time of an LED that is configured to operate in
Direct behavior mode. The rising edge time corresponds to the amount of time the LED takes to transition from its minimum
duty cycle to its maximum duty cycle. Conversely, the falling edge time corresponds to the amount of time that
the LED takes to transition from its maximum duty cycle to its minimum duty cycle.
Bits 5 - 3 - RISE_RATE[2:0] - Determines the rising edge time of an LED when it transitions from its minimum drive state
to its maximum drive state as shown in Table 6-62.
Bits 2 - 0 - FALL_RATE[2:0] - Determines the falling edge time of an LED when it transitions from its maximum drive
state to its minimum drive state as shown in Table 6-62.
TABLE 6-60: LED DUTY CYCLE DECODE
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
0 0 0 0 7% 0%
0 0 0 1 9% 7%
0 0 1 0 11% 9%
0 0 1 1 14% 11%
0 1 0 0 17% 14%
0 1 0 1 20% 17%
0 1 1 0 23% 20%
0 1 1 1 26% 23%
1 0 0 0 30% 26%
1 0 0 1 35% 30%
1 0 1 0 40% 35%
1 0 1 1 46% 40%
1 1 0 0 53% 46%
1 1 0 1 63% 53%
1 1 1 0 77% 63%
1 1 1 1 100% 77%
TABLE 6-61: LED DIRECT RAMP RATES REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
94h R/W LED Direct Ramp
Rates - - RISE_RATE[2:0] FALL_RATE[2:0] 00h
TABLE 6-62: RISE / FALL RATE DECODE
RISE_RATE/ FALL_RATE/ Bit Decode
Rise / Fall Time (TRISE / TFALL)
21 0
00 0 0
0 0 1 250ms
0 1 0 500ms
0 1 1 750ms
1 0 0 1s
1 0 1 1.25s
CAP1128
DS00001622B-page 60 2015 Microchip Technology Inc.
6.38 LED Off Delay Register
The LED Off Delay register determines the amount of time that an LED remains at its maximum duty cycle (or minimum
as determined by the polarity controls) before it starts to ramp down. If the LED is operating in Breathe mode, this delay
is applied at the top of each “breath”. If the LED is operating in the Direct mode, this delay is applied when the LED is
unactuated.
Bits 6 - 4 - BR_OFF_DLY[2:0] - Determines the Breathe behavior mode off delay, which is the amount of time an LED
in Breathe behavior mode remains inactive after it finishes a breathe pulse (ramp on and ramp off), as shown in Figure 6-
5 (non-inverted polarity LEDx_POL = 1) and Figure 6-6 (inverted polarity LEDx_POL = 0). Available settings are shown
in Table 6-64.
1 1 0 1.5s
1 1 1 2s
TABLE 6-63: LED OFF DELAY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
95h R/W LED Off Delay
Register - BR_OFF_DLY[2:0] DIR_OFF_DLY[3:0] 00h
FIGURE 6-5: Breathe Behavior with Non-Inverted Polarity
TABLE 6-62: RISE / FALL RATE DECODE (CONTINUED)
RISE_RATE/ FALL_RATE/ Bit Decode
Rise / Fall Time (TRISE / TFALL)
21 0
LED Actuated
100% - Breathe Max Min Cycle * Brightness
100% - Breathe Min Duty Cycle *
Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
2015 Microchip Technology Inc. DS00001622B-page 61
CAP1128
Bits 3 - 0 - DIR_OFF_DLY[3:0] - Determines the turn-off delay, as shown in Table 6-65, for all LEDs that are configured
to operate in Direct behavior mode.
The Direct behavior operation is determined by the combination of programmed Rise Time, Fall Time, Min and Max Duty
cycles, Off Delay, and polarity. Figure 6-7 shows the behavior for non-inverted polarity (LEDx_POL = 1) while Figure 6-
8 shows the behavior for inverted polarity (LEDx_POL = 0).
FIGURE 6-6: Breathe Behavior with Inverted Polarity
TABLE 6-64: BREATHE OFF DELAY SETTINGS
BR_OFF_DLY [2:0]
OFF Delay
2 10
0 0 0 0 (default)
0 0 1 0.25s
0 1 0 0.5s
0 1 1 0.75s
1 0 0 1.0s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2.0s
LED Actuated
Breathe Max Duty Cycle * Brightness
Breathe Min Duty Cycle * Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
CAP1128
DS00001622B-page 62 2015 Microchip Technology Inc.
FIGURE 6-7: Direct Behavior for Non-Inverted Polarity
FIGURE 6-8: Direct Behavior for Inverted Polarity
TABLE 6-65: OFF DELAY DECODE
OFF Delay[3:0] Bit Decode
OFF Delay (tOFF_DLY)
32 1 0
00 0 0 0
0 0 0 1 250ms
0 0 1 0 500ms
0 0 1 1 750ms
0 1 0 0 1s
0 1 0 1 1.25s
0 1 1 0 1.5s
0 1 1 1 2s
1 0 0 0 2.5s
1 0 0 1 3.0s
1 0 1 0 3.5s
1 0 1 1 4.0s
1 1 0 0 4.5s
All others 5.0s
Normal –
untouched
operation
RISE_RATE
Setting (tRISE)
(100% - Max Duty
Cycle) * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
(100% - Min Duty Cycle) *
Brightness LED
Brightness
Normal –
untouched
operation RISE_RATE
Setting (tRISE)
Min Duty Cycle * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
Max Duty Cycle * Brightness
LED
Brightness
2015 Microchip Technology Inc. DS00001622B-page 63
CAP1128
6.39 Sensor Input Calibration Registers
The Sensor Input Calibration registers hold the 10-bit value that represents the last calibration value.
6.40 Product ID Register
The Product ID register stores a unique 8-bit value that identifies the device.
6.41 Manufacturer ID Register
The Vendor ID register stores an 8-bit value that represents Microchip.
TABLE 6-66: SENSOR INPUT CALIBRATION REGISTERS
ADDR Register R/W B7 B6 B5 B4 B3 B2 B1 B0 Default
B1h Sensor Input 1
Calibration R CAL1_9 CAL1_8 CAL1_7 CAL1_6 CAL1_5 CAL1_4 CAL1_3 CAL1_2 00h
B2h Sensor Input 2
Calibration R CAL2_9 CAL2_8 CAL2_7 CAL2_6 CAL2_5 CAL2_4 CAL2_3 CAL2_2 00h
B3h Sensor Input 3
Calibration R CAL3_9 CAL3_8 CAL3_7 CAL3_6 CAL3_5 CAL3_4 CAL3_3 CAL3_2 00h
B4h Sensor Input 4
Calibration R CAL4_9 CAL4_8 CAL4_7 CAL4_6 CAL4_5 CAL4_4 CAL4_3 CAL4_2 00h
B5h Sensor Input 5
Calibration R CAL5_9 CAL5_8 CAL5_7 CAL5_6 CAL5_5 CAL5_4 CAL5_3 CAL5_2 00h
B6h Sensor Input 6
Calibration R CAL6_9 CAL6_8 CAL6_7 CAL6_6 CAL6_5 CAL6_4 CAL6_3 CAL6_2 00h
B7h Sensor Input 7
Calibration R CAL7_9 CAL7_8 CAL7_7 CAL7_6 CAL7_5 CAL7_4 CAL7_3 CAL7_2 00h
B8h Sensor Input 8
Calibration R CAL8_9 CAL8_8 CAL8_7 CAL8_6 CAL8_5 CAL8_4 CAL8_3 CAL8_2 00h
B9h
Sensor Input
Calibration LSB
1
R CAL4_1 CAL4_0 CAL3_1 CAL3_0 CAL2_1 CAL2_0 CAL1_1 CAL1_0 00h
BAh
Sensor Input
Calibration LSB
2
R CAL8_1 CAL8_0 CAL7_1 CAL7_0 CAL6_1 CAL6_0 CAL5_1 CAL5_0 00h
TABLE 6-67: PRODUCT ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FDh R Product ID 0 1 0 1 0 0 1 0 52h
TABLE 6-68: VENDOR ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FEh R Manufacturer ID 0 1 0 1 1 1 0 1 5Dh
CAP1128
DS00001622B-page 64 2015 Microchip Technology Inc.
6.42 Revision Register
The Revision register stores an 8-bit value that represents the part revision.
TABLE 6-69: REVISION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FFh R Revision 1 0 0 0 0 0 1 1 83h
2015 Microchip Technology Inc. DS00001622B-page 65
CAP1128
7.0 PACKAGE INFORMATION
7.1 CAP1128 Package Drawings
Note: For the most current package drawings, see the Microchip Packaging Specification at:
http://www.microchip.com/packaging.
FIGURE 7-1: 20-Pin QFN 4mm x 4mm Package Drawing
CAP1128
DS00001622B-page 66 2015 Microchip Technology Inc.
FIGURE 7-2: 20-Pin QFN 4mm x 4mm Package Dimensions
FIGURE 7-3: 20-Pin QFN 4mm x 4mm PCB Drawing
2015 Microchip Technology Inc. DS00001622B-page 67
CAP1128
7.2 Package Marking
FIGURE 7-4: CAP1128 Package Markings
C 1 28 - 1
Y WWN N N A
RCC
e3
TOP
BOTTOM
Bottom marking not allowed
PB-FREE/GREEN SYMBOL
(Matte Sn)
Lines 1-3:
Line 4:
Center Horizontal Alignment
Left Horizontal Alignment
PIN 1
0.41
3x 0.56
Line 1 – SMSC Logo without circled R symbol
Line 2 – Device ID, Version
Line 3 – Year, Week, Alphanumeric Traceability Code
Line 4 – Revision, Country Code
1
CAP1128
DS00001622B-page 68 2015 Microchip Technology Inc.
APPENDIX A: DEVICE DELTA
A.1 Delta from CAP1028 to CAP1128
1. Updated circuitry to improve power supply rejection.
2. Updated LED driver duty cycle decode values to have more distribution at lower values - closer to a logarithmic
curve. See Table 6-60, "LED Duty Cycle Decode".
3. Updated bug that breathe periods were not correct above 2.6s. This includes rise / fall time decodes above 1.5s.
4. Added filtering on RESET pin to prevent errant resets.
5. Updated controls so that the RESET pin assertion places the device into the lowest power state available and
causes an interrupt when released. See Section 5.2, "RESET Pin".
6. Added 1 bit to the LED Off Delay register (see Section 6.38, "LED Off Delay Register") to extend times from 2s
to 5s in 0.5s intervals.
7. Breathe behavior modified. A breathe off delay control was added to the LED Off Delay Register (see Section
6.38, "LED Off Delay Register") so the LEDs can be configured to remain inactive between breathes.
8. Added controls for the LED transition effects when linking LEDs to capacitive sensor inputs. See Section 6.29,
"Linked LED Transition Control Register".
9. Added controls to “mirror” the LED duty cycle outputs so that when polarity changes, the LED brightness levels
look right. These bits are automatically set when polarity is set. Added control to break this auto-set behavior.
See Section 6.30, "LED Mirror Control Register".
10. Added Multiple Touch Pattern detection circuitry. See Section 6.15, "Multiple Touch Pattern Configuration Register".
11. Added General Status register to flag Multiple touches, Multiple Touch Pattern issues and general touch detections.
See Section 6.2, "Status Registers".
12. Added bits 6 and 5 to the Recalibration Configuration register (2Fh - see Section 6.17, "Recalibration Configuration
Register"). These bits control whether the accumulation of intermediate data and the consecutive negative
delta counts counter are cleared when the noise status bit is set.
13. Added Configuration 2 register for LED linking controls, noise detection controls, and control to interrupt on press
but not on release. Added control to change alert pin polarity. See Section 6.6, "Configuration Registers".
14. Updated Deep Sleep behavior so that device does not clear DSLEEP bit on received communications but will
wake to communicate.
15. Changed PWM frequency for LED drivers. The PWM frequency was derived from the programmed breathe
period and duty cycle settings and it ranged from ~4Hz to ~8000 Hz. The PWM frequency has been updated to
be a fixed value of ~2000Hz.
16. Register delta:
Table A.1 Register Delta From CAP1028 to CAP1128
Address Register Delta Delta Default
00h
Page 31
Changed - Main Status /
Control
added bits 7-6 to control gain 00h
02h
Page 32
New - General Status new register to store MTP, MULT, LED,
RESET, and general TOUCH bits
00h
44h
Page 36
New - Configuration 2 new register to control alert polarity, LED
touch linking behavior, LED output behavior,
and noise detection, and interrupt on
release
40h
24h
Page 39
Changed - Averaging
Control
updated register bits - moved
SAMP_AVG[2:0] bits and added SAMP_-
TIME bit 1. Default changed
39h
2Bh
Page 43
New - Multiple Touch
Pattern Configuration
new register for Multiple Touch Pattern
configuration - enable and threshold settings
80h
2015 Microchip Technology Inc. DS00001622B-page 69
CAP1128
2Dh
Page 44
New - Multiple Touch
Pattern Register
new register for Multiple Touch Pattern
detection circuitry - pattern or number of
sensor inputs
FFh
2Fh
Page 44
Changed - Recalibration
Configuration
updated register - updated CAL_CFG bit
decode to add a 128 averages setting and
removed highest time setting. Default
changed. Added bit 6 NO_CLR_INTD and
bit 5 NO_CLR_NEG.
8Ah
38h
Page 46
Changed - Sensor Input
Noise Threshold
updated register bits - removed bits 7 - 3
and consolidated all controls into bits 1 - 0.
These bits will set the noise threshold for
all channels. Default changed
01h
39h Removed - Noise
Threshold Register 2
removed register n/a
41h
Page 47
Changed - Standby Configuration
updated register bits - moved
STBY_AVG[2:0] bits and added STBY_-
TIME bit 1. Default changed
39h
77h
Page 52
New - Linked LED Transition
Control
new register to control transition effect
when LED linked to sensor inputs
00h
79h
Page 53
New - LED Mirror Control new register to control LED output mirroring
for brightness control when polarity
changed
00h
90h
Page 58
Changed - LED Pulse 1
Duty Cycle
changed bit decode to be more logarithmic F0h
91h
Page 58
Changed - LED Pulse 2
Duty Cycle
changed bit decode to be more logarithmic F0h
92h
Page 58
Changed - LED Breathe
Duty Cycle
changed bit decode to be more logarithmic F0h
93h
Page 58
Changed - LED Direct
Duty Cycle
changed bit decode to be more logarithmic F0h
95h Added controls - LED Off
Delay
Added bits 6-4 BR_OFF_DLY[2:0]
Added bit 3 DIR_OFF_DLY[3]
00h
FDh
Page 63
Changed - Product ID Changed bit decode for CAP1128 52h
Table A.1 Register Delta From CAP1028 to CAP1128 (continued)
Address Register Delta Delta Default
CAP1128
DS00001622B-page 70 2015 Microchip Technology Inc.
APPENDIX B: DATA SHEET REVISION HISTORY
Revision Section/Figure/Entry Correction
DS00001622B (02-09-15)
Features, Table 2-1, Table 2-
2, "Pin Types", Section 5.0,
"General Description"
References to BC-Link Interface, BC_DATA, BC_-
CLK, BC-IRQ#, BC-Link bus have been removed
Application Note under Table
2-6
[BC-Link] hidden in data sheet
Table 3-2, "Electrical Specifications"
BC-Link Timing Section hidden in data sheet
Table 4-1 Protocol Used for 68K Pull Down Resistor changed
from “BC-Link Communications” to “Reserved”
Section 4.2.2, "SMBus
Address and RD / WR Bit"
Replaced “client address” with “slave address” in this
section.
Section 4.2.4, SMBus ACK
and NACK Bits, Section 4.2.5,
SMBus Stop Bit,Section 4.2.7,
SMBus and I2C Compatibility
Replaced “client” with “slave” in these sections.
Table 4-4, "Read Byte Protocol"
Heading changed from “Client Address” to “Slave
Address”
Table 6-1 Register Name for Register Address 77h changed
from “LED Linked Transition Control” to “Linked LED
Transition Control”
Section 6.30 changed CS2 to LED2
Section 7.7 Package Marking Updated package drawing
Appendix A: Device Delta changed 2Dh to 2Fh in item #12
Product Identification System Removed BC-Link references
REV A REV A replaces previous SMSC version Rev. 1.32 (01-05-12)
Rev. 1.32 (01-05-12) Table 3-2, "Electrical Specifications"
Added conditions for tHD:DAT.
Section 4.2.7, "SMBus and
I2C Compatibility"
Renamed from “SMBus and I2C Compliance.”
First paragraph, added last sentence: “For information
on using the CAP1188 in an I2C system, refer to
SMSC AN 14.0 SMSC Dedicated Slave Devices in
I
2C Systems.”
Added: CAP1188 supports I2C fast mode at 400kHz.
This covers the SMBus max time of 100kHz.
Section 6.4, "Sensor Input
Delta Count Registers"
Changed negative value cap from FFh to 80h.
Rev. 1.31 (08-18-11) Section 4.3.3, "SMBus Send
Byte"
Added an application note: The Send Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit is
set).
Section 4.3.4, "SMBus
Receive Byte"
Added an application note: The Receive Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit
is set).
Rev. 1.3 (05-18-11) Section 6.42, "Revision Register"
Updated revision ID from 82h to 83h.
Rev. 1.2 (02-10-11) Section A.8, "Delta from Rev
B (Mask B0) to Rev C (Mask
B1)"
Added.
Table 2-1, "Pin Description for
CAP1128"
Changed value in “Unused Connection” column for
the ADDR_COMM pin from “Connect to Ground” to
“n/a“.
2015 Microchip Technology Inc. DS00001622B-page 71
CAP1128
Table 3-2, "Electrical Specifications"
PSR improvements made in functional revision B.
Changed PSR spec from ±100 typ and ±200 max
counts / V to ±3 and ±10 counts / V. Conditions
updated.
Section 5.5.2, "Recalibrating
Sensor Inputs"
Added more detail with subheadings for each type of
recalibration.
Section 6.6, "Configuration
Registers"
Added bit 5 BLK_PWR_CTRL to the Configuration 2
Register 44h.
The TIMEOUT bit is set to ‘1’ by default for functional
revision B and is set to ‘0’ by default for functional
revision C.
Section 6.42, "Revision Register"
Updated revision ID in register FFh from 81h to 82h.
Rev. 1.1 (11-17-10) Document Updated for functional revision B. See Section A.7,
"Delta from Rev A (Mask A0) to Rev B (Mask B0)".
Cover Added to General Description: “includes circuitry and
support for enhanced sensor proximity detection.”
Added the following Features:
Calibrates for Parasitic Capacitance
Analog Filtering for System Noise Sources
Press and Hold feature for Volume-like Applications
Table 3-2, "Electrical Specifications"
Conditions for Power Supply Rejection modified adding
the following:
Sampling time = 2.56ms
Averaging = 1
Negative Delta Counts = Disabled
All other parameters default
Section 6.11, "Calibration Activate
Register"
Updated register description to indicate which re-calibration
routine is used.
Section 6.14, "Multiple Touch
Configuration Register"
Updated register description to indicate what will
happen.
Table 6-34, "CSx_BN_TH Bit
Decode"
Table heading changed from “Threshold Divide Setting”
to “Percent Threshold Setting”.
Rev. 1.0 (06-14-10) Initial release
Revision Section/Figure/Entry Correction
CAP1128
DS00001622B-page 72 2015 Microchip Technology Inc.
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Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains
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To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification”
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CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
• Local Sales Office
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Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://www.microchip.com/support
2015 Microchip Technology Inc. DS00001622B-page 73
CAP1128
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. [X] - 1 - XXX - [X](1)
l l l l
Device Temperature Package Tape and Reel
Range Option
Example:
Note 1: Tape and Reel identifier only appears in the catalog part number description. This identifier is used for ordering
purposes and is not printed on the device package. Check with your Microchip Sales Office for package availability
with the Tape and Reel option.
Device: CAP1128
Temperature
Range:
Blank = 0°C to +85°C (Extended Commercial)
Package: BP = QFN
Tape and
Reel Option:
TR = Tape and Reel(1)
CAP1128-1-BP-TR
20-pin QFN 4mm x 4mm (RoHS compliant)
Eight capacitive touch sensor inputs, Two
LED drivers, Dedicated Wake, Reset,
SMBus / BC-Link / SPI interfaces
Reel size is 4,000 pieces
CAP1128
DS00001622B-page 74 2015 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device applications and the like is provided only for your convenience and may be
superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO
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or otherwise, under any Microchip intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC, FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer, LANCheck,
MediaLB, MOST, MOST logo, MPLAB, OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC, SST, SST Logo, SuperFlash and
UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are registered trademarks of Microchip Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit Serial
Programming, ICSP, Inter-Chip Connectivity, KleerNet, KleerNet logo, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK,
MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, RightTouch logo, REAL ICE, SQI, Serial
Quad I/O, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.
Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.
GestIC is a registered trademarks of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in
other countries.
All other trademarks mentioned herein are property of their respective companies.
© 2015, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
ISBN: 9781632770325
Microchip received ISO/TS-16949:2009 certification for its worldwide
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are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
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analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
2015 Microchip Technology Inc. DS00001622B-page 75
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Au format texte
2015 Microchip Technology Inc. DS00001621B-page 1
General Description
The CAP1166, which incorporates RightTouch® technology,
is a multiple channel Capacitive Touch sensor
with multiple power LED drivers. It contains six (6) individual
capacitive touch sensor inputs with programmable
sensitivity for use in touch sensor applications.
Each sensor input automatically recalibrates to compensate
for gradual environmental changes.
The CAP1166 also contains six (6) LED drivers that
offer full-on / off, variable rate blinking, dimness controls,
and breathing. Each of the LED drivers may be
linked to one of the sensor inputs to be actuated when
a touch is detected. As well, each LED driver may be
individually controlled via a host controller.
The CAP1166 includes Multiple Pattern Touch recognition
that allows the user to select a specific set of buttons
to be touched simultaneously. If this pattern is
detected, then a status bit is set and an interrupt generated.
Additionally, the CAP1166 includes circuitry and support
for enhanced sensor proximity detection.
The CAP1166 offers multiple power states operating at
low quiescent currents. In the Standby state of operation,
one or more capacitive touch sensor inputs are
active and all LEDs may be used. If a touch is detected,
it will wake the system using the WAKE/SPI_MOSI pin.
Deep Sleep is the lowest power state available, drawing
5uA (typical) of current. In this state, no sensor
inputs are active. Driving the WAKE/SPI_MOSI pin or
communications will wake the device.
Applications
• Desktop and Notebook PCs
• LCD Monitors
• Consumer Electronics
• Appliances
Features
• Six (6) Capacitive Touch Sensor Inputs
- Programmable sensitivity
- Automatic recalibration
- Individual thresholds for each button
• Proximity Detection
• Multiple Button Pattern Detection
• Calibrates for Parasitic Capacitance
• Analog Filtering for System Noise Sources
• Press and Hold feature for Volume-like Applications
• Multiple Communication Interfaces
- SMBus / I2C compliant interface
- SPI communications
- Pin selectable communications protocol and
multiple slave addresses (SMBus / I2C only)
• Low Power Operation
- 5uA quiescent current in Deep Sleep
- 50uA quiescent current in Standby (1 sensor
input monitored)
- Samples one or more channels in Standby
• Six (6) LED Driver Outputs
- Open Drain or Push-Pull
- Programmable blink, breathe, and dimness
controls
- Can be linked to Capacitive Touch Sensor
inputs
• Dedicated Wake output flags touches in low
power state
• System RESET pin
• Available in 20-pin 4mm x 4mm QFN or 24-pin
SSOP RoHS compliant package
CAP1166
6 Channel Capacitive Touch Sensor with 6 LED Drivers
CAP1166
DS00001621B-page 2 2015 Microchip Technology Inc.
TO OUR VALUED CUSTOMERS
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The last character of the literature number is the version number, (e.g., DS30000000A is version A of document DS30000000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the
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To determine if an errata sheet exists for a particular device, please check with one of the following:
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When contacting a sales office, please specify which device, revision of silicon and data sheet (include -literature number) you are
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2015 Microchip Technology Inc. DS00001621B-page 3
CAP1166
Table of Contents
1.0 Block Diagram ................................................................................................................................................................................. 4
2.0 Pin Description ................................................................................................................................................................................ 5
3.0 Electrical Specifications .................................................................................................................................................................. 9
4.0 Communications ........................................................................................................................................................................... 12
5.0 General Description ...................................................................................................................................................................... 23
6.0 Register Description ...................................................................................................................................................................... 29
7.0 Package Information ..................................................................................................................................................................... 67
Appendix A: Device Delta ................................................................................................................................................................... 72
Appendix B: Data Sheet Revision History ........................................................................................................................................... 74
The Microchip Web Site ...................................................................................................................................................................... 76
Customer Change Notification Service ............................................................................................................................................... 76
Customer Support ............................................................................................................................................................................... 76
Product Identification System ............................................................................................................................................................. 77
2015 Microchip Technology Inc. DS00001621B-page 4
CAP1166
1.0 BLOCK DIAGRAM
SMBus /
BC-Link or
SPI Slave
Protocol
SMCLK / BC_CLK /
SPI_CLK
SMDATA BC_DATA / SPI_MSIO/
SPI_MISO
VDD GND
ALERT# / BC_IRQ#
Capacitive Touch Sensing Algorithm
LED1
CS1 CS2 CS3 CS4 CS5 CS6
LED Driver, Breathe, and
Dimness control
RESET WAKE / SPI_MOSI
ADDR_COMM
SPI_CS#
LED2 LED3
LED4 LED5 LED6
CAP1166
DS00001621B-page 5 2015 Microchip Technology Inc.
2.0 PIN DESCRIPTION
FIGURE 2-1: CAP1166 Pin Diagram (20-Pin QFN)
1
2
3
4
15
14
13
12
20
19
18
17
6
7
8
9
5
10
11
16
CAP1166
20 pin QFN
GND
LED2
LED3
LED4
LED5
LED6
SMCLK / BC_CLK / SPI_CLK
WAKE / SPI_MOSI
SPI_CS#
LED1
SMDATA / BC_DATA / SPI_MSIO /
SPI_MISO
RESET
CS1
CS2
CS3
CS6
CS5
ADDR_COMM
CS4
ALERT# / BC_IRQ#
VDD
2015 Microchip Technology Inc. DS00001621B-page 6
CAP1166
FIGURE 2-2: CAP1166 Pin Diagram (24-pin SSOP)
TABLE 2-1: PIN DESCRIPTION FOR CAP1166
Pin
Number
(QFN 20)
Pin
Number
(SSOP 24)
Pin Name Pin Function Pin Type Unused
Connection
1 4 SPI_CS# Active low chip-select for SPI bus DI (5V) Connect to
Ground
2 5 WAKE / SPI_-
MOSI
WAKE - Active high wake / interrupt output
Standby power state - requires pull-down resistor
WAKE - Active high wake input - requires pull-down
resistor
Deep Sleep power state
DO
Pull-down
Resistor DI
SPI_MOSI - SPI Master-Out-Slave-In port when used
in normal mode DI (5V) Connect to
GND
CAP1166
24 SSOP
24
23
22
21
20
17
19
18
16
13
15
14
1
2
3
4
5
8
6
7
9
12
10
11
CS1
RESET
SPI_CS#
WAKE / SPI_MOSI
SMDATA /SPI_MSIO / SPI_MISO
SMCLK / SPI_CLK
LED1
LED2
LED3
GND LED4
GND
LED5
LED6
ALERT# / BC_IRQ#
ADDR_COMM
CS6
CS5
CS4
CS3
CS2
VDD
N/C
N/C
CAP1166
DS00001621B-page 7 2015 Microchip Technology Inc.
3 6
SMDATA /
SPI_MSIO /
SPI_MISO
SMDATA - Bi-directional, open-drain SMBus data -
requires pull-up resistor DIOD (5V)
n/a SPI_MSIO - SPI Master-Slave-In-Out bidirectional port
when used in bi-directional mode DIO
SPI_MISO - SPI Master-In-Slave-Out port when used
in normal mode DO
4 8 SMCLK /
SPI_CLK
SMCLK - SMBus clock input - requires pull-up resistor DI (5V)
SPI_CLK - SPI clock input DI (5V) n/a
5 9 LED1
Open drain LED 1 driver (default) OD (5V) Connect to
Ground
Push-pull LED 1 driver DO
leave open or
connect to
Ground
6 10 LED2
Open drain LED 2 driver (default) OD (5V) Connect to
Ground
Push-pull LED 2 driver DO
leave open or
connect to
Ground
7 11 LED3
Open drain LED 3 driver (default) OD (5V) Connect to
Ground
Push-pull LED 3 driver DO
leave open or
connect to
Ground
8 13 LED4
Open drain LED 4 driver (default) OD (5V) Connect to
Ground
Push-pull LED 4 driver DO
leave open or
connect to
Ground
9 15 LED5
Open drain LED 5 driver (default) OD (5V) Connect to
Ground
Push-pull LED 5 driver DO
leave open or
connect to
Ground
10 16 LED6
Open drain LED 6 driver (default) OD (5V) Connect to
Ground
Push-pull LED 6 driver DO
leave open or
connect to
Ground
TABLE 2-1: PIN DESCRIPTION FOR CAP1166 (CONTINUED)
Pin
Number
(QFN 20)
Pin
Number
(SSOP 24)
Pin Name Pin Function Pin Type Unused
Connection
2015 Microchip Technology Inc. DS00001621B-page 8
CAP1166
APPLICATION NOTE: When the ALERT# pinis configured as an active low output, it will be open drain. When it is
configured as an active high output, it will be push-pull.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the pull-up voltage must not exceed 3.6V
when the CAP1166 is unpowered.
APPLICATION NOTE: The SPI_CS# pin should be grounded when SMBus, or I2C,communications are used.
The pin types are described in Table 2-2. All pins labeled with (5V) are 5V tolerant.
11 17 ALERT#
ALERT# - Active low alert / interrupt output for SMBus
alert or SPI interrupt
- requires pull-up resistor (default)
OD (5V) Connect to
GND
ALERT# - Active high push-pull alert / interrupt output
for SMBus alert or SPI interrupt DO High-Z
12 18 ADDR_
COMM
Address / communications select pin - pull-down resistor
determines address / communications mechanism AI n/a
13 19 CS6 Capacitive Touch Sensor Input 6 AIO Connect to
Ground
14 20 CS5 Capacitive Touch Sensor Input 5 AIO Connect to
Ground
15 21 CS4 Capacitive Touch Sensor Input 4 AIO Connect to
Ground
16 22 CS3 Capacitive Touch Sensor Input 3 AIO Connect to
Ground
17 23 CS2 Capacitive Touch Sensor Input 2 AIO Connect to
Ground
18 24 CS1 Capacitive Touch Sensor Input 1 AIO Connect to
Ground
19 1 VDD Positive Power supply Power n/a
20 1 RESET Active high soft reset for system - resets all registers to
default values. If not used, connect to ground. DI (5V) Connect to
Ground
Bottom Pad
12 GND Ground Power n/a
14 GND Ground Power n/a
TABLE 2-1: PIN DESCRIPTION FOR CAP1166 (CONTINUED)
Pin
Number
(QFN 20)
Pin
Number
(SSOP 24)
Pin Name Pin Function Pin Type Unused
Connection
CAP1166
DS00001621B-page 9 2015 Microchip Technology Inc.
TABLE 2-2: PIN TYPES
Pin Type Description
Power This pin is used to supply power or ground to the device.
DI Digital Input - This pin is used as a digital input. This pin is 5V tolerant.
AIO Analog Input / Output -This pin is used as an I/O for analog signals.
DIOD Digital Input / Open Drain Output - This pin is used as a digital I/O. When it is used as an output,
it is open drain and requires a pull-up resistor. This pin is 5V tolerant.
OD Open Drain Digital Output - This pin is used as a digital output. It is open drain and requires a
pull-up resistor. This pin is 5V tolerant.
DO Push-pull Digital Output - This pin is used as a digital output and can sink and source current.
DIO Push-pull Digital Input / Output - This pin is used as an I/O for digital signals.
2015 Microchip Technology Inc. DS00001621B-page 10
CAP1166
3.0 ELECTRICAL SPECIFICATIONS
Note 3-1 Stresses above those listed could cause permanent damage to the device. This is a stress rating
only and functional operation of the device at any other condition above those indicated in the
operation sections of this specification is not implied.
Note 3-2 For the 5V tolerant pins that have a pull-up resistor, the voltage difference between V5VT_PIN and VDD
must never exceed 3.6V.
Note 3-3 The Package Power Dissipation specification assumes a recommended thermal via design consisting
of a 3x3 matrix of 0.3mm (12mil) vias at 1.0mm pitch connected to the ground plane with a 2.5 x
2.5mm thermal landing.
Note 3-4 Junction to Ambient (θJA) is dependent on the design of the thermal vias. Without thermal vias and
a thermal landing, the θJA is approximately 60°C/W including localized PCB temperature increase.
TABLE 3-1: ABSOLUTE MAXIMUM RATINGS
Voltage on 5V tolerant pins (V5VT_PIN) -0.3 to 5.5 V
Voltage on 5V tolerant pins (|V5VT_PIN - VDD|) Note 3-2 0 to 3.6 V
Voltage on VDD pin -0.3 to 4 V
Voltage on any other pin to GND -0.3 to VDD + 0.3 V
Package Power Dissipation up to TA = 85°C for 20 pin QFN
(see Note 3-3)
0.9 W
Junction to Ambient (θJA) (see Note 3-4) 58 °C/W
Operating Ambient Temperature Range -40 to 125 °C
Storage Temperature Range -55 to 150 °C
ESD Rating, All Pins, HBM 8000 V
CAP1166
DS00001621B-page 11 2015 Microchip Technology Inc.
TABLE 3-2: ELECTRICAL SPECIFICATIONS
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
DC Power
Supply Voltage VDD 3.0 3.3 3.6 V
Supply Current
ISTBY 120 170 uA
Standby state active
1 sensor input monitored
No LEDs active
Default conditions (8 avg, 70ms
cycle time)
ISTBY 50 uA
Standby state active
1 sensor input monitored
No LEDs active
1 avg, 140ms cycle time,
IDSLEEP 5 15 uA
Deep Sleep state active
LEDs at 100% or 0% Duty Cycle
No communications
TA < 40°C
3.135 < VDD < 3.465V
IDD 500 600 uA Capacitive Sensing Active
No LEDs active
Capacitive Touch Sensor Inputs
Maximum Base
Capacitance CBASE 50 pF Pad untouched
Minimum Detectable
Capacitive Shift ΔCTOUCH 20 fF
Pad touched - default conditions (1
avg, 35ms cycle time, 1x sensitivity)
Recommended Cap
Shift ΔCTOUCH 0.1 2 pF Pad touched - Not tested
Power Supply Rejection
PSR ±3 ±10 counts /
V
Untouched Current Counts
Base Capacitance 5pF - 50pF
Maximum sensitivity
Negative Delta Counts disabled
All other parameters default
Timing
RESET Pin Delay tRST_DLY 10 ms
Time to communications
ready tCOMM_DLY 15 ms
Time to first conversion
ready tCONV_DLY 170 200 ms
LED Drivers
Duty Cycle DUTYLED 0 100 % Programmable
Drive Frequency fLED 2 kHz
Sinking Current ISINK 24 mA VOL = 0.4
Sourcing Current ISOURCE 24 mA VOH = VDD - 0.4
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
I/O Pins
Output Low Voltage VOL 0.4 V ISINK_IO = 8mA
Output High Voltage VOH VDD - 0.4 V ISOURCE_IO = 8mA
2015 Microchip Technology Inc. DS00001621B-page 12
CAP1166
Note 3-5 The ALERT pin will not glitch high or low at power up if connected to VDD or another voltage.
Note 3-6 The SMCLK and SMDATA pins will not glitch low at power up if connected to VDD or another voltage.
Input High Voltage VIH 2.0 V
Input Low Voltage VIL 0.8 V
Leakage Current ILEAK ±5 uA
powered or unpowered
TA < 85°C
pull-up voltage < 3.6V if unpowered
RESET Pin Release
to conversion ready tRESET 170 200 ms
SMBus Timing
Input Capacitance CIN 5 pF
Clock Frequency fSMB 10 400 kHz
Spike Suppression tSP 50 ns
Bus Free Time Stop to
Start tBUF 1.3 us
Start Setup Time tSU:STA 0.6 us
Start Hold Time tHD:STA 0.6 us
Stop Setup Time tSU:STO 0.6 us
Data Hold Time tHD:DAT 0 us When transmitting to the master
Data Hold Time tHD:DAT 0.3 us When receiving from the master
Data Setup Time tSU:DAT 0.6 us
Clock Low Period tLOW 1.3 us
Clock High Period tHIGH 0.6 us
Clock / Data Fall Time tFALL 300 ns Min = 20+0.1CLOAD ns
Clock / Data Rise
Time tRISE 300 ns Min = 20+0.1CLOAD ns
Capacitive Load CLOAD 400 pF per bus line
SPI Timing
Clock Period tP 250 ns
Clock Low Period tLOW 0.4 x tP 0.6 x tP ns
Clock High Period tHIGH 0.4 x tP 0.6 x tP ns
Clock Rise / Fall time tRISE / tFALL 0.1 x tP ns
Data Output Delay tD:CLK 10 ns
Data Setup Time tSU:DAT 20 ns
Data Hold Time tHD:DAT 20 ns
SPI_CS# to SPI_CLK
setup time tSU:CS 0 ns
Wake Time tWAKE 10 20 us SPI_CS# asserted to CLK assert
TABLE 3-2: ELECTRICAL SPECIFICATIONS (CONTINUED)
VDD = 3V to 3.6V, TA = 0°C to 85°C, all typical values at TA = 27°C unless otherwise noted.
Characteristic Symbol Min Typ Max Unit Conditions
2015 Microchip Technology Inc. DS00001621B-page 13
CAP1166
4.0 COMMUNICATIONS
4.1 Communications
The CAP1166communicates using the 2-wire SMBus or I2C bus, the 2-wire proprietary BC-Link, or the SPI bus. If the
proprietary BC-Link protocol is required for your application, please contact your Microchip representative for ordering
instructions. Regardless of communication mechanism, the device functionality remains unchanged. The communications
mechanism as well as the SMBus (or I2C) slave address is determined by the resistor connected between the
ADDR_COMM pin and ground as shown in Table 4-1.
4.1.1 SMBUS (I2C) COMMUNICATIONS
When configured to communicate via the SMBus, the CAP1166 supports the following protocols: Send Byte, Receive
Byte, Read Byte, Write Byte, Read Block, and Write Block. In addition, the device supports I2C formatting for block read
and block write protocols.
APPLICATION NOTE: For SMBus/I2C communications, the SPI_CS# pin is not used and should be grounded; any
data presented to this pin will be ignored.
See Section 4.2 and Section 4.3 for more information on the SMBus bus and protocols respectively.
4.1.2 SPI COMMUNICATIONS
When configured to communicate via the SPI bus, the CAP1166supports both bi-directional 3-wire and normal 4-wire
protocols and uses the SPI_CS# pin to enable communications.
APPLICATION NOTE: See Section 4.5 and Section 4.6 for more information on the SPI bus and protocols
respectively.Upon power up, the CAP1166 will not respond to any communications for up to
15ms. After this time, full functionality is available.
4.2 System Management Bus
The CAP1166 communicates with a host controller, such as an SIO, through the SMBus. The SMBus is a two-wire serial
communication protocol between a computer host and its peripheral devices. A detailed timing diagram is shown in
Figure 4-1. Stretching of the SMCLK signal is supported; however, the CAP1166 will not stretch the clock signal.
TABLE 4-1: ADDR_COMM PIN DECODE
Pull-Down Resistor (+/- 5%) Protocol Used SMBus Address
GND SPI Communications using Normal
4-wire Protocol Used
n/a
56k SPI Communications using BiDirectional
3-wire Protocol Used
n/a
68k Reserved n/a
82k SMBus / I2C 0101_100(r/w)
100k SMBus / I2C 0101_011(r/w)
120k SMBus / I2C 0101_010(r/w)
150k SMBus / I2C 0101_001(r/w)
VDD SMBus / I2C 0101_000(r/w)
CAP1166
DS00001621B-page 14 2015 Microchip Technology Inc.
4.2.1 SMBUS START BIT
The SMBus Start bit is defined as a transition of the SMBus Data line from a logic ‘1’ state to a logic ‘0’ state while the
SMBus Clock line is in a logic ‘1’ state.
4.2.2 SMBUS ADDRESS AND RD / WR BIT
The SMBus Address Byte consists of the 7-bit slave address followed by the RD / WR indicator bit. If this RD / WR bit
is a logic ‘0’, then the SMBus Host is writing data to the slave device. If this RD / WR bit is a logic ‘1’, then the SMBus
Host is reading data from the slave device.
See Table 4-1 for available SMBus addresses.
4.2.3 SMBUS DATA BYTES
All SMBus Data bytes are sent most significant bit first and composed of 8-bits of information.
4.2.4 SMBUS ACK AND NACK BITS
The SMBus slave will acknowledge all data bytes that it receives. This is done by the slave device pulling the SMBus
Data line low after the 8th bit of each byte that is transmitted. This applies to both the Write Byte and Block Write protocols.
The Host will NACK (not acknowledge) the last data byte to be received from the slave by holding the SMBus data line
high after the 8th data bit has been sent. For the Block Read protocol, the Host will ACK each data byte that it receives
except the last data byte.
4.2.5 SMBUS STOP BIT
The SMBus Stop bit is defined as a transition of the SMBus Data line from a logic ‘0’ state to a logic ‘1’ state while the
SMBus clock line is in a logic ‘1’ state. When the CAP1166 detects an SMBus Stop bit and it has been communicating
with the SMBus protocol, it will reset its slave interface and prepare to receive further communications.
4.2.6 SMBUS TIMEOUT
The CAP1166 includes an SMBus timeout feature. Following a 30ms period of inactivity on the SMBus where the
SMCLK pin is held low, the device will timeout and reset the SMBus interface.
The timeout function defaults to disabled. It can be enabled by setting the TIMEOUT bit in the Configuration register
(see Section 6.6, "Configuration Registers").
4.2.7 SMBUS AND I2C COMPATIBILITY
The major differences between SMBus and I2C devices are highlighted here. For more information, refer to the SMBus
2.0 and I2C specifications. For information on using the CAP1166 in an I2C system, refer to AN 14.0 Dedicated Slave
Devices in I2C Systems.
FIGURE 4-1: SMBus Timing Diagram
SMDATA
SMCLK
TLOW
TRISE
THIGH
TFALL
TBUF
THD:STA
P S S - Start Condition P - Stop Condition
THD:DAT TSU:DAT TSU:STA
THD:STA
P
TSU:STO
S
2015 Microchip Technology Inc. DS00001621B-page 15
CAP1166
1. CAP1166 supports I2C fast mode at 400kHz. This covers the SMBus max time of 100kHz.
2. Minimum frequency for SMBus communications is 10kHz.
3. The SMBus slave protocol will reset if the clock is held at a logic ‘0’ for longer than 30ms. This timeout functionality
is disabled by default in the CAP1166 and can be enabled by writing to the TIMEOUT bit. I2C does not have
a timeout.
4. The SMBus slave protocol will reset if both the clock and data lines are held at a logic ‘1’ for longer than 200µs
(idle condition). This function is disabled by default in the CAP1166 and can be enabled by writing to the TIMEOUT
bit. I2C does not have an idle condition.
5. I2C devices do not support the Alert Response Address functionality (which is optional for SMBus).
6. I2C devices support block read and write differently. I2C protocol allows for unlimited number of bytes to be sent
in either direction. The SMBus protocol requires that an additional data byte indicating number of bytes to read /
write is transmitted. The CAP1166 supports I2C formatting only.
4.3 SMBus Protocols
The CAP1166 is SMBus 2.0 compatible and supports Write Byte, Read Byte, Send Byte, and Receive Byte as valid
protocols as shown below.
All of the below protocols use the convention in Table 4-2.
4.3.1 SMBUS WRITE BYTE
The Write Byte is used to write one byte of data to a specific register as shown in Table 4-3.
4.3.2 SMBUS READ BYTE
The Read Byte protocol is used to read one byte of data from the registers as shown in Table 4-4.
4.3.3 SMBUS SEND BYTE
The Send Byte protocol is used to set the internal address register pointer to the correct address location. No data is
transferred during the Send Byte protocol as shown in Table 4-5.
APPLICATION NOTE: The Send Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
TABLE 4-2: PROTOCOL FORMAT
Data Sent to
Device
Data Sent to the
HOst
Data sent Data sent
TABLE 4-3: WRITE BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK Stop
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0 0 -> 1
TABLE 4-4: READ BYTE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data NACK Stop
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-5: SEND BYTE PROTOCOL
Start Slave Address WR ACK Register Address ACK Stop
1 -> 0 YYYY_YYY 0 0 XXh 0 0 -> 1
CAP1166
DS00001621B-page 16 2015 Microchip Technology Inc.
4.3.4 SMBUS RECEIVE BYTE
The Receive Byte protocol is used to read data from a register when the internal register address pointer is known to
be at the right location (e.g., set via Send Byte). This is used for consecutive reads of the same register as shown in
Table 4-6.
APPLICATION NOTE: The Receive Byte protocol is not functional in Deep Sleep (i.e., DSLEEP bit is set).
4.4 I2C Protocols
The CAP1166 supports I2C Block Write and Block Read.
The protocols listed below use the convention in Table 4-2.
4.4.1 BLOCK WRITE
The Block Write is used to write multiple data bytes to a group of contiguous registers as shown in Table 4-7.
APPLICATION NOTE: When using the Block Write protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.4.2 BLOCK READ
The Block Read is used to read multiple data bytes from a group of contiguous registers as shown in Table 4-8.
APPLICATION NOTE: When using the Block Read protocol, the internal address pointer will be automatically
incremented after every data byte is received. It will wrap from FFh to 00h.
4.5 SPI Interface
The SMBus has a predefined packet structure, the SPI does not. The SPI Bus can operate in two modes of operation,
normal 4-wire mode and bi-directional 3-wire mode. All SPI commands consist of 8-bit packets sent to a specific slave
device (identified by the CS pin).
The SPI bus will latch data on the rising edge of the clock and the clock and data both idle high.
All commands are supported via both operating modes. The supported commands are: Reset Serial interface, set
address pointer, write command and read command. Note that all other codes received during the command phase are
ignored and have no effect on the operation of the device.
TABLE 4-6: RECEIVE BYTE PROTOCOL
Start Slave Address RD ACK Register Data NACK Stop
1 -> 0 YYYY_YYY 1 0 XXh 1 0 -> 1
TABLE 4-7: BLOCK WRITE PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Register Data ACK
1 ->0 YYYY_YYY 0 0 XXh 0 XXh 0
Register Data ACK Register
Data
ACK . . . Register
Data
ACK Stop
XXh 0 XXh 0 . . . XXh 0 0 -> 1
TABLE 4-8: BLOCK READ PROTOCOL
Start Slave
Address WR ACK Register
Address ACK Start Slave
Address RD ACK Register
Data
1->0 YYYY_YYY 0 0 XXh 0 1 ->0 YYYY_YYY 1 0 XXh
ACK Register
Data
ACK Register
Data
ACK Register
Data
ACK . . . Register
Data
NACK Stop
0 XXh 0 XXh 0 XXh 0 . . . XXh 1 0 -> 1
2015 Microchip Technology Inc. DS00001621B-page 17
CAP1166
4.5.1 SPI NORMAL MODE
The SPI Bus can operate in two modes of operation, normal and bi-directional mode. In the normal mode of operation,
there are dedicated input and output data lines. The host communicates by sending a command along the CAP1166
SPI_MOSI data line and reading data on the SPI_MISO data line. Both communications occur simultaneously which
allows for larger throughput of data transactions.
All basic transfers consist of two 8 bit transactions from the Master device while the slave device is simultaneously sending
data at the current address pointer value.
Data writes consist of two or more 8-bit transactions. The host sends a specific write command followed by the data to
write the address pointer. Data reads consist of one or more 8-bit transactions. The host sends the specific read data
command and continues clocking for as many data bytes as it wishes to receive.
4.5.2 SPI BI-DIRECTIONAL MODE
In the bi-directional mode of operation, the SPI data signals are combined into the SPI_MSIO line, which is shared for
data received by the device and transmitted by the device. The protocol uses a simple handshake and turn around
sequence for data communications based on the number of clocks transmitted during each phase.
All basic transfers consist of two 8 bit transactions. The first is an 8 bit command phase driven by the Master device.
The second is by an 8 bit data phase driven by the Master for writes, and by the CAP1166 for read operations.
The auto increment feature of the address pointer allows for successive reads or writes. The address pointer will return
to 00h after reaching FFh.
4.5.3 SPI_CS# PIN
The SPI Bus is a single master, multiple slave serial bus. Each slave has a dedicated CS pin (chip select) that the master
asserts low to identify that the slave is being addressed. There are no formal addressing options.
4.5.4 ADDRESS POINTER
All data writes and reads are accessed from the current address pointer. In both Bi-directional mode and Full Duplex
mode, the Address pointer is automatically incremented following every read command or every write command.
The address pointer will return to 00h after reaching FFh.
4.5.5 SPI TIMEOUT
The CAP1166 does not detect any timeout conditions on the SPI bus.
FIGURE 4-2: SPI Timing
SPI_MSIO or
SPI_MOSI or
SPI_MISO
SPI_CLK
tLOW
tRISE
tHIGH
tFALL
tD:CLK tHD:DAT
tSU:DAT
tP
2015 Microchip Technology Inc. DS00001621B-page 18
CAP1166 4.6 Normal SPI Protocols When operating in normal mode, the SPI bus internal address pointer is incremented depending upon which command has been transmitted. Multiple commands may be transmitted sequentually so long as the SPI_CS# pin is asserted low. Figure 4-3 shows an example of this operation.
4.6.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the transaction - command or data, the receipt of the
successive reset commands resets the Serial communication interface only. All other functions are not affected by the reset operation.
FIGURE 4-3: Example SPI Bus Communication - Normal Mode
SPI_CS#
SPI_MISO
SPI_MOSI
SPI Address Pointer
SPI Data output buffer
Register Address /
Data
7Ah
XXh
(invalid)
XXh
(invalid)
YYh
(invalid)
7Ah 7Dh 41h
YYh
(invalid)
7Eh 66h
XXh
(invalid) 45h
7Dh 41h
AAh
(invalid)
AAh
(invalid)
7Fh 7Fh
55h
(invalid) 66h
7Fh
AAh
7Dh
43h
40h
78h
7Fh
XXh
(invalid)
7Fh
56h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
45h
40h / 56h
41h / 45h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
55h
7Fh
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
41h
66h
42h
AAh
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
44h
80h
40h
80h
40h
56h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
43h
55h
7Fh 7Fh
55h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h /78h
80h
45h
43h
46h
78h
40h / 56h
41h / 66h
42h / AAh
43h / 55h
44h / 80h
45h / 43h
46h / 78h
00h
XXh
Indicates SPI Address pointer incremented
2015 Microchip Technology Inc. DS00001621B-page 19
CAP1166
4.6.2 SET ADDRESS POINTER
The Set Address Pointer command sets the Address pointer for subsequent reads and writes of data. The pointer is set
on the rising edge of the final data bit. At the same time, the data that is to be read is fetched and loaded into the internal
output buffer but is not transmitted.
4.6.3 WRITE DATA
The Write Data protocol updates the contents of the register referenced by the address pointer. As the command is processed,
the data to be read is fetched and loaded into the internal output buffer but not transmitted. Then, the register
is updated with the data to be written. Finally, the address pointer is incremented.
FIGURE 4-4: SPI Reset Interface Command - Normal Mode
FIGURE 4-5: SPI Set Address Pointer Command - Normal Mode
Master SPDOUT
SPI_MOSI
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
Invalid register data 00h – Internal Data buffer empty SPI_MISO
Master Drives Slave Drives
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘1’ ‘0’
Master SPDOUT
SPI_MOSI Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
SPI_MISO Unknown, Invalid Data Unknown, Invalid Data
Master Drives Slave Drives Address pointer set
‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1166
DS00001621B-page 20 2015 Microchip Technology Inc.
4.6.4 READ DATA
The Read Data protocol is used to read data from the device. During the normal mode of operation, while the device is
receiving data, the CAP1166 is simultaneously transmitting data to the host. For the Set Address commands and the
Write Data commands, this data may be invalid and it is recommended that the Read Data command is used.
FIGURE 4-6: SPI Write Command - Normal Mode
FIGURE 4-7: SPI Read Command - Normal Mode
Master SPDOUT
SPI_MOSI Data to Write
SPI_CS#
SPI_CLK
Write Command – 7Eh
Unknown, Invalid Data Old Data at Current Address Pointer SPI_MISO
Master Drives Slave Drives
1. Data written at current
address pointer
2. Address pointer incremented
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
First Read Command – 7Fh
SPI_CS#
SPI_MISO Invalid, Unknown Data *
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Subsequent Read
Commands – 7F
Data at Current Address Pointer
Address Pointer
Incremented **
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
* The first read command after any other command will return invalid data for the first
byte. Subsequent read commands will return the data at the Current Address Pointer
** The Address Pointer is incremented 8 clocks after the Read Command has been
received. Therefore continually sending Read Commands will result in each command
reporting new data. Once Read Commands have been finished, the last data byte will be
read during the next 8 clocks for any command
2015 Microchip Technology Inc. DS00001621B-page 21
CAP1166
4.7 Bi-Directional SPI Protocols
4.7.1 RESET INTERFACE
Resets the Serial interface whenever two successive 7Ah codes are received. Regardless of the current phase of the
transaction - command or data, the receipt of the successive reset commands resets the Serial communication interface
only. All other functions are not affected by the reset operation.
4.7.2 SET ADDRESS POINTER
Sets the address pointer to the register to be accessed by a read or write command. This command overrides the autoincrementing
of the address pointer.
FIGURE 4-8: SPI Read Command - Normal Mode - Full
FIGURE 4-9: SPI Reset Interface Command - Bi-directional Mode
Master SPDOUT
SPI_MOSI
Master Drives Slave Drives
SPI_CLK
Read Command – 7Fh
SPI_CS#
Data at previously set register address = current
address pointer
SPI_MISO ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
XXh
1. Register Read Address
updated to Current SPI Read
Address pointer
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous address
pointer + 1 = current address
pointer
1. Register Read Address
incremented = current address
pointer + 1
1. SPI Read Address
Incremented = new current
address pointer
2. Register Read Address
Incremented = current address
pointer +1
Register Data loaded into
Output buffer = data at current
address pointer + 1
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Data at previously set register address = current
address pointer (SPI)
1. Register data loaded into
output buffer = data at current
address pointer
1. Output buffer transmitted =
data at previous register
address pointer + 1 = current
address pointer
1. Output buffer transmitted =
data at current address pointer
+ 1
2. Flag set to increment SPI
Read Address at end of next 8
clocks
Subsequent Read Commands – 7Fh
1. Register Read Address
updated to Current SPI Read
Address pointer.
2. Register Read Address
incremented = current address
pointer +1 – end result =
register address pointer doesn’t
change
Master SPDOUT
SPI_MSIO
SPI_CS#
SPI_CLK
Reset - 7Ah Reset - 7Ah
‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’ ‘0’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
CAP1166
DS00001621B-page 22 2015 Microchip Technology Inc.
4.7.3 WRITE DATA
Writes data value to the register address stored in the address pointer. Performs auto increment of address pointer after
the data is loaded into the register.
4.7.4 READ DATA
Reads data referenced by the address pointer. Performs auto increment of address pointer after the data is transferred
to the Master.
FIGURE 4-10: SPI Set Address Pointer Command - Bi-directional Mode
FIGURE 4-11: SPI Write Data Command - Bi-directional Mode
FIGURE 4-12: SPI Read Data Command - Bi-directional Mode
Master SPDOUT
SPI_MSIO Register Address
SPI_CS#
SPI_CLK
Set Address Pointer – 7Dh
‘0’ ‘1’ ‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
Master SPDOUT
SPI_MSIO Register Write Data
SPI_CS#
SPI_CLK
Write Command – 7Eh
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘0’
Master SPDOUT
SPI_MSIO
Master Drives Slave Drives Indeterminate
Register Read Data
SPI_CLK
Read Command – 7Fh
SPI_CS#
‘0’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’ ‘1’
2015 Microchip Technology Inc. DS00001621B-page 23
CAP1166
4.8 BC-Link Interface
The BC-Link is a proprietary bus developed to allow communication between a host controller device to a companion
device. This device uses this serial bus to read and write registers and for interrupt processing. The interface uses a
data port concept, where the base interface has an address register, data register and a control register, defined in the
8051’s SFR space.
Refer to documentation for the BC-Link compatible host controller for details on how to access the CAP1166 via the BCLink
Interface.
2015 Microchip Technology Inc. DS00001621B-page 24
CAP1166
5.0 GENERAL DESCRIPTION
The CAP1166 is a multiple channel Capacitive Touch sensor with multiple power LED drivers. It contains six (6) individual
capacitive touch sensor inputs with programmable sensitivity for use in touch sensor applications. Each sensor input
automatically recalibrates to compensate for gradual environmental changes.
The CAP1166 also contains six (6) low side (or push-pull) LED drivers that offer full-on / off, variable rate blinking, dimness
controls, and breathing. Each of the LED drivers may be linked to one of the sensor inputs to be actuated when a
touch is detected. As well, each LED driver may be individually controlled via a host controller.
Finally, the device contains a dedicated RESET pin to act as a soft reset by the system.
The CAP1166 offers multiple power states. It operates at the lowest quiescent current during its Deep Sleep state. In
the low power Standby state, it can monitor one or more channels and respond to communications normally. The device
contains a wake pin (WAKE/SPI_MOSI) output to wake the system when a touch is detected in Standby and to wake
the device from Deep Sleep.
The device communicates with a host controller using the SPI bus, or via SMBus / I2C. The host controller may poll the
device for updated information at any time or it may configure the device to flag an interrupt whenever a touch is
detected on any sensor pad.
A typical system diagram is shown in Figure 5-1.
CAP1166
DS00001621B-page 25 2015 Microchip Technology Inc.
5.1 Power States
The CAP1166 has three operating states depending on the status of the STBY and DSLEEP bits. When the device transitions
between power states, previously detected touches (for inactive channels) are cleared and the status bits reset.
1. Fully Active - The device is fully active. It is monitoring all active capacitive sensor inputs and driving all LED channels
as defined.
2. Standby - The device is in a lower power state. It will measure a programmable number of channels using the
Standby Configuration controls (see Section 6.20 through Section 6.22). Interrupts will still be generated based
on the active channels. The device will still respond to communications normally and can be returned to the Fully
FIGURE 5-1: System Diagram for CAP1166
CAP1166
CS4
SMDATA / BC_DATA / SPI_MSIO / SPI_MISO
SMCLK / BC_CLK / SPI_CLK
VDD Embedded Controller ALERT# / BC_IRQ#
CS5
CS6
3.3V – 5V
CS3
CS2
CS1
WAKE / SPI_MOSI
RESET
SPI_CS#
ADDR_COMM
LED6
LED5
LED4
LED1
LED2
LED3
3.3V – 5V
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
Touch
Button
2015 Microchip Technology Inc. DS00001621B-page 26
CAP1166
Active state of operation by clearing the STBY bit.
3. Deep Sleep - The device is in its lowest power state. It is not monitoring any capacitive sensor inputs and not
driving any LEDs. All LEDs will be driven to their programmed non-actuated state and no PWM operations will
be done. While in Deep Sleep, the device can be awakened by SMBus or SPI communications targeting the
device. This will not cause the DSLEEP to be cleared so the device will return to Deep Sleep once all communications
have stopped.
If the device is not communicating via the 4-wire SPI bus, then during this state of operation, if the WAKE/SPI_MOSI
pin is driven high by an external source, the device will clear the DSLEEP bit and return to Fully Active.
APPLICATION NOTE: In the Deep Sleep state, the LED output will be either high or low and will not be PWM’d at
the min or max duty cycle.
5.2 RESET Pin
The RESET pin is an active high reset that is driven from an external source. While it is asserted high, all the internal
blocks will be held in reset including the communications protocol used. No capacitive touch sensor inputs will be sampled
and the LEDs will not be driven. All configuration settings will be reset to default states and all readings will be
cleared.
The device will be held in Deep Sleep that can only be removed by driving the RESET pin low. This will cause the
RESET status bit to be set to a logic ‘1’ and generate an interrupt.
5.3 WAKE/SPI_MOSI Pin Operation
The WAKE / SPI_MOSI pin is a multi-function pin depending on device operation. When the device is configured to communicate
using the 4-wire SPI bus, this pin is an input.
However, when the CAP1166 is placed in Standby and is not communicating using the 4-wire SPI protocol, the WAKE
pin is an active high output. In this condition, the device will assert the WAKE/SPI_MOSI pin when a touch is detected
on one of its sampled sensor inputs. The pin will remain asserted until the INT bit has been cleared and then it will be
de-asserted.
When the CAP1166 is placed in Deep Sleep and it is not communicating using the 4-wire SPI protocol, the WAKE/SPI_-
MOSI pin is monitored by the device as an input. If the WAKE/SPI_MOSI pin is driven high by an external source, the
CAP1166will clear the DSLEEP bit causing the device to return to Fully Active.
When the device is placed in Deep Sleep, this pin is a High-Z input and must have a pull-down resistor to GND for proper
operation.
5.4 LED Drivers
The CAP1166 contains six (6) LED drivers. Each LED driver can be linked to its respective capacitive touch sensor input
or it can be controlled by the host. Each LED driver can be configured to operate in one of the following modes with
either push-pull or open drain drive.
1. Direct - The LED is configured to be on or off when the corresponding input stimulus is on or off (or inverted). The
brightness of the LED can be programmed from full off to full on (default). Additionally, the LED contains controls
to individually configure ramping on, off, and turn-off delay.
2. Pulse 1 - The LED is configured to “Pulse” (transition ON-OFF-ON) a programmable number of times with programmable
rate and min / max brightness. This behavior may be actuated when a press is detected or when a
release is detected.
3. Pulse 2 - The LED is configured to “Pulse” while actuated and then “Pulse” a programmable number of times with
programmable rate and min / max brightness when the sensor pad is released.
4. Breathe - The LED is configured to transition continuously ON-OFF-ON (i.e. to “Breathe”) with a programmable
rate and min / max brightness.
When an LED is not linked to a sensor and is actuated by the host, there’s an option to assert the ALERT# pin when
the initiated LED behavior has completed.
5.4.1 LINKING LEDS TO CAPACITIVE TOUCH SENSOR INPUTS
All LEDs can be linked to the corresponding capacitive touch sensor input so that when the sensor input detects a touch,
the corresponding LED will be actuated at one of the programmed responses.
CAP1166
DS00001621B-page 27 2015 Microchip Technology Inc.
5.5 Capacitive Touch Sensing
The CAP1166 contains six (6) independent capacitive touch sensor inputs. Each sensor input has dynamic range to
detect a change of capacitance due to a touch. Additionally, each sensor input can be configured to be automatically
and routinely re-calibrated.
5.5.1 SENSING CYCLE
Each capacitive touch sensor input has controls to be activated and included in the sensing cycle. When the device is
active, it automatically initiates a sensing cycle and repeats the cycle every time it finishes. The cycle polls through each
active sensor input starting with CS1 and extending through CS6. As each capacitive touch sensor input is polled, its
measurement is compared against a baseline “Not Touched” measurement. If the delta measurement is large enough,
a touch is detected and an interrupt is generated.
The sensing cycle time is programmable (see Section 6.10, "Averaging and Sampling Configuration Register").
5.5.2 RECALIBRATING SENSOR INPUTS
There are various options for recalibrating the capacitive touch sensor inputs. Recalibration re-sets the Base Count Registers
(Section 6.24, "Sensor Input Base Count Registers") which contain the “not touched” values used for touch detection
comparisons.
APPLICATION NOTE: The device will recalibrate all sensor inputs that were disabled when it transitions from
Standby. Likewise, the device will recalibrate all sensor inputs when waking out of Deep
Sleep.
5.5.2.1 Manual Recalibration
The Calibration Activate Registers (Section 6.11, "Calibration Activate Register") force recalibration of selected sensor
inputs. When a bit is set, the corresponding capacitive touch sensor input will be recalibrated (both analog and digital).
The bit is automatically cleared once the recalibration routine has finished.
5.5.2.2 Automatic Recalibration
Each sensor input is regularly recalibrated at a programmable rate (see Section 6.17, "Recalibration Configuration Register").
By default, the recalibration routine stores the average 64 previous measurements and periodically updates the
base “not touched” setting for the capacitive touch sensor input.
5.5.2.3 Negative Delta Count Recalibration
It is possible that the device loses sensitivity to a touch. This may happen as a result of a noisy environment, an accidental
recalibration during a touch, or other environmental changes. When this occurs, the base untouched sensor input
may generate negative delta count values. The NEG_DELTA_CNT bits (see Section 6.17, "Recalibration Configuration
Register") can be set to force a recalibration after a specified number of consecutive negative delta readings.
5.5.2.4 Delayed Recalibration
It is possible that a “stuck button” occurs when something is placed on a button which causes a touch to be detected
for a long period. By setting the MAX_DUR_EN bit (see Section 6.6, "Configuration Registers"), a recalibration can be
forced when a touch is held on a button for longer than the duration specified in the MAX_DUR bits (see Section 6.8,
"Sensor Input Configuration Register").
Note: During this recalibration routine, the sensor inputs will not detect a press for up to 200ms and the Sensor
Base Count Register values will be invalid. In addition, any press on the corresponding sensor pads will
invalidate the recalibration.
Note: Automatic recalibration only works when the delta count is below the active sensor input threshold. It is disabled
when a touch is detected.
Note: During this recalibration, the device will not respond to touches.
2015 Microchip Technology Inc. DS00001621B-page 28
CAP1166
5.5.3 PROXIMITY DETECTION
Each sensor input can be configured to detect changes in capacitance due to proximity of a touch. This circuitry detects
the change of capacitance that is generated as an object approaches, but does not physically touch, the enabled sensor
pad(s). When a sensor input is selected to perform proximity detection, it will be sampled from 1x to 128x per sampling
cycle. The larger the number of samples that are taken, the greater the range of proximity detection is available at the
cost of an increased overall sampling time.
5.5.4 MULTIPLE TOUCH PATTERN DETECTION
The multiple touch pattern (MTP) detection circuitry can be used to detect lid closure or other similar events. An event
can be flagged based on either a minimum number of sensor inputs or on specific sensor inputs simultaneously exceeding
an MTP threshold or having their Noise Flag Status Register bits set. An interrupt can also be generated. During an
MTP event, all touches are blocked (see Section 6.15, "Multiple Touch Pattern Configuration Register").
5.5.5 LOW FREQUENCY NOISE DETECTION
Each sensor input has an EMI noise detector that will sense if low frequency noise is injected onto the input with sufficient
power to corrupt the readings. If this occurs, the device will reject the corrupted sample and set the corresponding
bit in the Noise Status register to a logic ‘1’.
5.5.6 RF NOISE DETECTION
Each sensor input contains an integrated RF noise detector. This block will detect injected RF noise on the CS pin. The
detector threshold is dependent upon the noise frequency. If RF noise is detected on a CS line, that sample is removed
and not compared against the threshold.
5.6 ALERT# Pin
The ALERT# pin is an active low (or active high when configured) output that is driven when an interrupt event is
detected.
Whenever an interrupt is generated, the INT bit (see Section 6.1, "Main Control Register") is set. The ALERT# pin is
cleared when the INT bit is cleared by the user. Additionally, when the INT bit is cleared by the user, status bits are only
cleared if no touch is detected.
5.6.1 SENSOR INTERRUPT BEHAVIOR
The sensor interrupts are generated in one of two ways:
1. An interrupt is generated when a touch is detected and, as a user selectable option, when a release is detected
(by default - see Section 6.6). See Figure 5-3.
2. If the repeat rate is enabled then, so long as the touch is held, another interrupt will be generated based on the
programmed repeat rate (see Figure 5-2).
When the repeat rate is enabled, the device uses an additional control called MPRESS that determines whether a touch
is flagged as a simple “touch” or a “press and hold”. The MPRESS[3:0] bits set a minimum press timer. When the button
is touched, the timer begins. If the sensor pad is released before the minimum press timer expires, it is flagged as a
touch and an interrupt is generated upon release. If the sensor input detects a touch for longer than this timer value, it
is flagged as a “press and hold” event. So long as the touch is held, interrupts will be generated at the programmed
repeat rate and upon release (if enabled).
APPLICATION NOTE: Figure 5-2 and Figure 5-3 show default operation which is to generate an interrupt upon
sensor pad release and an active-low ALERT# pin.
APPLICATION NOTE: The host may need to poll the device twice to determine that a release has been detected.
Note: Delayed recalibration only works when the delta count is above the active sensor input threshold. If
enabled, it is invoked when a sensor pad touch is held longer than the MAX_DUR bit setting.
CAP1166
DS00001621B-page 29 2015 Microchip Technology Inc.
FIGURE 5-2: Sensor Interrupt Behavior - Repeat Rate Enabled
FIGURE 5-3: Sensor Interrupt Behavior - No Repeat Rate Enabled
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms)
Min Press Setting
(280ms)
Interrupt on
Touch
Button Repeat Rate
(175ms)
Button Repeat Rate
(175ms)
Interrupt on
Release
(optional)
ALERT# pin
(active low)
Touch Detected
INT bit
Button Status
Write to INT bit
Polling Cycle
(35ms) Interrupt on
Touch Interrupt on
Release
(optional)
ALERT# pin
(active low)
2015 Microchip Technology Inc. DS00001621B-page 30
CAP1166
6.0 REGISTER DESCRIPTION
The registers shown in Table 6-1 are accessible through the communications protocol. An entry of ‘-’ indicates that the
bit is not used and will always read ‘0’.
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER
Register
Address R/W Register Name Function Default Value Page
00h R/W Main Control Controls general power states and
power dissipation 00h Page 33
02h R General Status Stores general status bits 00h Page 34
03h R Sensor Input Status Returns the state of the sampled
capacitive touch sensor inputs 00h Page 34
04h R LED Status Stores status bits for LEDs 00h Page 34
0Ah R Noise Flag Status Stores the noise flags for sensor inputs 00h Page 35
10h R Sensor Input 1 Delta
Count Stores the delta count for CS1 00h Page 35
11h R Sensor Input 2 Delta
Count Stores the delta count for CS2 00h Page 35
12h R Sensor Input 3 Delta
Count Stores the delta count for CS3 00h Page 35
13h R Sensor Input 4 Delta
Count Stores the delta count for CS4 00h Page 35
14h R Sensor Input 5 Delta
Count Stores the delta count for CS5 00h Page 35
15h R Sensor Input 6 Delta
Count Stores the delta count for CS6 00h Page 35
1Fh R/W Sensitivity Control
Controls the sensitivity of the threshold
and delta counts and data scaling of
the base counts
2Fh Page 36
20h R/W Configuration Controls general functionality 20h Page 37
21h R/W Sensor Input Enable Controls whether the capacitive touch
sensor inputs are sampled 3Fh Page 38
22h R/W Sensor Input Configuration
Controls max duration and auto-repeat
delay for sensor inputs operating in the
full power state
A4h Page 39
23h R/W Sensor Input Configuration
2
Controls the MPRESS controls for all
sensor inputs 07h Page 40
24h R/W Averaging and Sampling
Config
Controls averaging and sampling window
39h Page 41
26h R/W Calibration Activate Forces re-calibration for capacitive
touch sensor inputs 00h Page 42
27h R/W Interrupt Enable Enables Interrupts associated with
capacitive touch sensor inputs 3Fh Page 42
28h R/W Repeat Rate Enable Enables repeat rate for all sensor
inputs 3Fh Page 43
2Ah R/W Multiple Touch Configuration
Determines the number of simultaneous
touches to flag a multiple touch
condition
80h Page 43
2Bh R/W Multiple Touch Pattern
Configuration
Determines the multiple touch pattern
(MTP) configuration 00h Page 44
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DS00001621B-page 31 2015 Microchip Technology Inc.
2Dh R/W Multiple Touch Pattern
Determines the pattern or number of
sensor inputs used by the MTP circuitry
3Fh Page 45
2Fh R/W Recalibration Configuration
Determines re-calibration timing and
sampling window 8Ah Page 45
30h R/W Sensor Input 1 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 1
40h Page 47
31h R/W Sensor Input 2 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 2
40h Page 47
32h R/W Sensor Input 3 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 3
40h Page 47
33h R/W Sensor Input 4 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 4
40h Page 47
34h R/W Sensor Input 5 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 5
40h Page 47
35h R/W Sensor Input 6 Threshold
Stores the delta count threshold to
determine a touch for Capacitive
Touch Sensor Input 6
40h Page 47
38h R/W Sensor Input Noise
Threshold
Stores controls for selecting the noise
threshold for all sensor inputs 01h Page 47
Standby Configuration Registers
40h R/W Standby Channel Controls which sensor inputs are
enabled while in standby 00h Page 47
41h R/W Standby Configuration Controls averaging and cycle time
while in standby 39h Page 48
42h R/W Standby Sensitivity Controls sensitivity settings used while
in standby 02h Page 49
43h R/W Standby Threshold Stores the touch detection threshold
for active sensor inputs in standby 40h Page 50
44h R/W Configuration 2 Stores additional configuration controls
for the device 40h Page 37
Base Count Registers
50h R Sensor Input 1 Base
Count
Stores the reference count value for
sensor input 1 C8h Page 50
51h R Sensor Input 2 Base
Count
Stores the reference count value for
sensor input 2 C8h Page 50
52h R Sensor Input 3 Base
Count
Stores the reference count value for
sensor input 3 C8h Page 50
53h R Sensor Input 4 Base
Count
Stores the reference count value for
sensor input 4 C8h Page 50
54h R Sensor Input 5 Base
Count
Stores the reference count value for
sensor input 5 C8h Page 50
55h R Sensor Input 6 Base
Count
Stores the reference count value for
sensor input 6 C8h Page 50
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001621B-page 32
CAP1166
LED Controls
71h R/W LED Output Type Controls the output type for the LED
outputs 00h Page 50
72h R/W Sensor Input LED Linking
Controls linking of sensor inputs to
LED channels 00h Page 51
73h R/W LED Polarity Controls the output polarity of LEDs 00h Page 51
74h R/W LED Output Control Controls the output state of the LEDs 00h Page 52
77h R/W Linked LED
Transition Control
Controls the transition when LEDs are
linked to CS channels 00h Page 53
79h R/W LED Mirror Control Controls the mirroring of duty cycles
for the LEDs 00h Page 54
81h R/W LED Behavior 1 Controls the behavior and response of
LEDs 1 - 4 00h Page 55
82h R/W LED Behavior 2 Controls the behavior and response of
LEDs 5 - 6 00h Page 55
84h R/W LED Pulse 1 Period Controls the period of each breathe
during a pulse 20h Page 56
85h R/W LED Pulse 2 Period Controls the period of the breathing
during breathe and pulse operation 14h Page 58
86h R/W LED Breathe Period Controls the period of an LED breathe
operation 5Dh Page 59
88h R/W LED Config Controls LED configuration 04h Page 59
90h R/W LED Pulse 1 Duty Cycle Determines the min and max duty
cycle for the pulse operation F0h Page 60
91h R/W LED Pulse 2 Duty Cycle Determines the min and max duty
cycle for breathe and pulse operation F0h Page 60
92h R/W LED Breathe Duty Cycle Determines the min and max duty
cycle for the breathe operation F0h Page 60
93h R/W LED Direct Duty Cycle Determines the min and max duty
cycle for Direct mode LED operation F0h Page 60
94h R/W LED Direct Ramp Rates Determines the rising and falling edge
ramp rates of the LEDs 00h Page 61
95h R/W LED Off Delay Determines the off delay for all LED
behaviors 00h Page 61
B1h R Sensor Input 1 Calibration
Stores the upper 8-bit calibration value
for sensor input 1 00h Page 64
B2h R Sensor Input 2 Calibration
Stores the upper 8-bit calibration value
for sensor input 2 00h Page 64
B3h R Sensor Input 3 Calibration
Stores the upper 8-bit calibration value
for sensor input 3 00h Page 64
B4h R Sensor Input 4 Calibration
Stores the upper 8-bit calibration value
for sensor input 4 00h Page 64
B5h R Sensor Input 5 Calibration
Stores the upper 8-bit calibration value
for sensor input 5 00h Page 64
B6h R Sensor Input 6 Calibration
Stores the upper 8-bit calibration value
for sensor input 6 00h Page 64
B9h R Sensor Input Calibration
LSB 1
Stores the 2 LSBs of the calibration
value for sensor inputs 1 - 4 00h Page 64
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
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DS00001621B-page 33 2015 Microchip Technology Inc.
During Power-On-Reset (POR), the default values are stored in the registers. A POR is initiated when power is first
applied to the part and the voltage on the VDD supply surpasses the POR level as specified in the electrical characteristics.
Any reads to undefined registers will return 00h. Writes to undefined registers will not have an effect.
When a bit is “set”, this means that the user writes a logic ‘1’ to it. When a bit is “cleared”, this means that the user writes
a logic ‘0’ to it.
6.1 Main Control Register
The Main Control register controls the primary power state of the device.
Bits 7 - 6 - GAIN[1:0] - Controls the gain used by the capacitive touch sensing circuitry. As the gain is increased, the
effective sensitivity is likewise increased as a smaller delta capacitance is required to generate the same delta count
values. The sensitivity settings may need to be adjusted along with the gain settings such that data overflow does not
occur.
APPLICATION NOTE: The gain settings apply to both Standby and Active states.
Bit 5 - STBY - Enables Standby.
• ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - Capacitive touch sensor input scanning is limited to the sensor inputs set in the Standby Channel register (see
Section 6.20). The status registers will not be cleared until read. LEDs that are linked to capacitive touch sensor
inputs will remain linked and active. Sensor inputs that are no longer sampled will flag a release and then remain
in a non-touched state. LEDs that are manually controlled will be unaffected.
• Bit 4 - DSLEEP - Enables Deep Sleep by deactivating all functions. This bit will be cleared when the WAKE pin is
driven high. ‘0’ (default) - Sensor input scanning is active and LEDs are functional.
• ‘1’ - All sensor input scanning is disabled. All LEDs are driven to their programmed non-actuated state and no
PWM operations will be done. The status registers are automatically cleared and the INT bit is cleared.
Bit 0 - INT - Indicates that there is an interrupt. When this bit is set, it asserts the ALERT# pin. If a channel detects a
touch and its associated interrupt enable bit is not set to a logic ‘1’, no action is taken.
BAh R Sensor Input Calibration
LSB 2
Stores the 2 LSBs of the calibration
value for sensor inputs 5 - 6 00h Page 64
FDh R Product ID Stores a fixed value that identifies
each product 51h Page 65
FEh R Manufacturer ID Stores a fixed value that identifies
Microchip 5Dh Page 65
FFh R Revision Stores a fixed value that represents
the revision number 83h Page 65
TABLE 6-2: MAIN CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
00h R/W Main Control GAIN[1:0] STBY DSLEEP - - - INT 00h
TABLE 6-3: GAIN BIT DECODE
GAIN[1:0]
Capacitive Touch Sensor Gain
1 0
0 0 1
01 2
10 4
11 8
TABLE 6-1: REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address R/W Register Name Function Default Value Page
2015 Microchip Technology Inc. DS00001621B-page 34
CAP1166
This bit is cleared by writing a logic ‘0’ to it. When this bit is cleared, the ALERT# pin will be deasserted and all status
registers will be cleared if the condition has been removed. If the WAKE/SPI_MOSI pin is asserted as a result of a touch
detected while in Standby, it will likewise be deasserted when this bit is cleared.
Note that the WAKE / SPI_MOSI pin is not driven when communicating via the 4-wire SPI protocol.
• ‘0’ - No interrupt pending.
• ‘1’ - A touch has been detected on one or more channels and the interrupt has been asserted.
6.2 Status Registers
All status bits are cleared when the device enters the Deep Sleep (DSLEEP = ‘1’ - see Section 6.1).
6.2.1 GENERAL STATUS - 02H
Bit 4 - LED - Indicates that one or more LEDs have finished their programmed activity. This bit is set if any bit in the LED
Status register is set.
Bit 3 - RESET - Indicates that the device has come out of reset. This bit is set when the device exits a POR state or
when the RESET pin has been deasserted and qualified via the RESET pin filter (see Section 5.2). This bit will cause
the INT bit to be set and is cleared when the INT bit is cleared.
Bit 2 - MULT - Indicates that the device is blocking detected touches due to the Multiple Touch detection circuitry (see
Section 6.14). This bit will not cause the INT bit to be set and hence will not cause an interrupt.
Bit 1 - MTP - Indicates that the device has detected a number of sensor inputs that exceed the MTP threshold either via
the pattern recognition or via the number of sensor inputs (see Section 6.15). This bit will cause the INT bit to be set if
the MTP_ALERT bit is also set. This bit will not be cleared until the condition that caused it to be set has been removed.
Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status register is set.
6.2.2 SENSOR INPUT STATUS - 03H
The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value of ‘0’ in any bit
indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a touch has been detected.
All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor input is no longer
present. If a touch is still detected, the bits will not be cleared (but this will not cause the interrupt to be asserted - see
Section 6.6).
Bit 5 - CS6 - Indicates that a touch was detected on Sensor Input 6. This sensor input can be linked to LED6.
Bit 4 - CS5 - Indicates that a touch was detected on Sensor Input 5. This sensor input can be linked to LED5.
Bit 3 - CS4 - Indicates that a touch was detected on Sensor Input 4. This sensor input can be linked to LED4.
Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3. This sensor input can be linked to LED3.
Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2. This sensor input can be linked to LED2.
Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1. This sensor input can be linked to LED1.
6.2.3 LED STATUS - 04H
The LED Status Registers indicate when an LED has completed its configured behavior (see Section 6.31, "LED Behavior
Registers") after being actuated by the host (see Section 6.28, "LED Output Control Register"). These bits are
ignored when the LED is linked to a capacitive sensor input. All LED Status bits are cleared when the INT bit is cleared.
Bit 5 - LED6_DN - Indicates that LED6 has finished its behavior after being actuated by the host.
Bit 4 - LED5_DN - Indicates that LED5 has finished its behavior after being actuated by the host.
TABLE 6-4: STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
02h R General Status - - - LED RESET MULT MTP TOUCH 00h
03h R Sensor Input Status
- - CS6 CS5 CS4 CS3 CS2 CS1 00h
04h R LED Status - - LED6_
DN
LED5_
DN
LED4_
DN
LED3_
DN
LED2_
DN
LED1_
DN 00h
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DS00001621B-page 35 2015 Microchip Technology Inc.
Bit 3 - LED4_DN - Indicates that LED4 has finished its behavior after being actuated by the host.
Bit 2 - LED3_DN - Indicates that LED3 has finished its behavior after being actuated by the host.
Bit 1 - LED2_DN - Indicates that LED2 has finished its behavior after being actuated by the host.
Bit 0 - LED1_DN - Indicates that LED1 has finished its behavior after being actuated by the host.
6.3 Noise Flag Status Registers
The Noise Flag Status registers store status bits that are generated from the analog block if the detected noise is above
the operating region of the analog detector or the RF noise detector. These bits indicate that the most recently received
data from the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a particular
channel, the delta count value is reset to 00h and thus no touch is detected.
These bits are not sticky and will be cleared automatically if the analog block does not report a noise error.
APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP
threshold (see Section 5.5.4, "Multiple Touch Pattern Detection") even if the corresponding
delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not
counted twice.
APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a
sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,
if RF noise is detected on a sensor input, that sample will be discarded unless the
DIS_RF_NOISE bit is set.
6.4 Sensor Input Delta Count Registers
The Sensor Input Delta Count registers store the delta count that is compared against the threshold used to determine
if a touch has been detected. The count value represents a change in input due to the capacitance associated with a
touch on one of the sensor inputs and is referenced to a calibrated base “Not Touched” count value. The delta is an
instantaneous change and is updated once per sensor input per sensing cycle (see Section 5.5.1, "Sensing Cycle").
The value presented is a standard 2’s complement number. In addition, the value is capped at a value of 7Fh. A reading
of 7Fh indicates that the sensitivity settings are too high and should be adjusted accordingly (see Section 6.5).
The value is also capped at a negative value of 80h for negative delta counts which may result upon a release.
TABLE 6-5: NOISE FLAG STATUS REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
0Ah R Noise Flag Status - - CS6_
NOISE
CS5_
NOISE
CS4_
NOISE
CS3_
NOISE
CS2_
NOISE
CS1_
NOISE 00h
TABLE 6-6: SENSOR INPUT DELTA COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
10h R Sensor Input 1
Delta Count Sign 64 32 16 8 4 2 1 00h
11h R Sensor Input 2
Delta Count Sign 64 32 16 8 4 2 1 00h
12h R Sensor Input 3
Delta Count Sign 64 32 16 8 4 2 1 00h
13h R Sensor Input 4
Delta Count Sign 64 32 16 8 4 2 1 00h
14h R Sensor Input 5
Delta Count Sign 64 32 16 8 4 2 1 00h
15h R Sensor Input 6
Delta Count Sign 64 32 16 8 4 2 1 00h
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CAP1166
6.5 Sensitivity Control Register
The Sensitivity Control register controls the sensitivity of a touch detection.
Bits 6-4 DELTA_SENSE[2:0] - Controls the sensitivity of a touch detection. The sensitivity settings act to scale the relative
delta count value higher or lower based on the system parameters. A setting of 000b is the most sensitive while a
setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a smaller delta capacitance
corresponding to a “lighter” touch. These settings are more sensitive to noise, however, and a noisy environment may
flag more false touches with higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely, a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
Bits 3 - 0 - BASE_SHIFT[3:0] - Controls the scaling and data presentation of the Base Count registers. The higher the
value of these bits, the larger the range and the lower the resolution of the data presented. The scale factor represents
the multiplier to the bit-weighting presented in these register descriptions.
APPLICATION NOTE: The BASE_SHIFT[3:0] bits normally do not need to be updated. These settings will not affect
touch detection or sensitivity. These bits are sometimes helpful in analyzing the Cap Sensing
board performance and stability.
TABLE 6-7: SENSITIVITY CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
1Fh R/W Sensitivity Control - DELTA_SENSE[2:0] BASE_SHIFT[3:0] 2Fh
TABLE 6-8: DELTA_SENSE BIT DECODE
DELTA_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-9: BASE_SHIFT BIT DECODE
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
0 0 0 0 1x
0 0 0 1 2x
0 0 1 0 4x
0 0 1 1 8x
0 1 0 0 16x
0 1 0 1 32x
0 1 1 0 64x
CAP1166
DS00001621B-page 37 2015 Microchip Technology Inc.
6.6 Configuration Registers
The Configuration registers control general global functionality that affects the entire device.
6.6.1 CONFIGURATION - 20H
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
• ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The SMBus interface
will not time out if the clock line is held low. Likewise, it will not reset if both the data and clock lines are held
high for longer than 200us. This is used for I2C compliance.
• ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The SMBus interface
will time out if the clock line is held low for longer than 30ms. Likewise, it will reset if both the data and clock
lines are held high for longer than 200us.
Bit 6 - WAKE_CFG - Configures the operation of the WAKE pin.
• ‘0’ (default) - The WAKE pin is not asserted when a touch is detected while the device is in Standby. It will still be
used to wake the device from Deep Sleep when driven high.
• ‘1’ - The WAKE pin will be asserted high when a touch is detected while the device is in Standby. It will also be
used to wake the device from Deep Sleep when driven high.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 6.19, "Sensor Input Noise Threshold
Register") is used by the device. Setting this bit disables the feature.
• ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does not exceed the
touch threshold, the sample is discarded and not used for the automatic re-calibration routine.
• ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold is used for the
automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the corresponding channel
is set to 0. Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
• ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held indefinitely and no
re-calibration will be performed on any sensor input.
• ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than the MAX_DUR
bit settings, then the re-calibration routine will be restarted (see Section 6.8).
0 1 1 1 128x
1 0 0 0 256x
All others 256x
(default = 1111b)
TABLE 6-10: CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
20h R/W Configuration TIMEOUT WAKE_
CFG
DIS_ DIG_
NOISE
DIS_ ANA_
NOISE
MAX_
DUR_EN - --
A0h
(Rev B)
20h
(rev C)
44h R/W Configuration 2 INV_LINK_
TRAN
ALT_
POL
BLK_PWR_
CTRL
BLK_POL_
MIR
SHOW_
RF_
NOISE
DIS_
RF_
NOISE
- INT_
REL_n 40h
TABLE 6-9: BASE_SHIFT BIT DECODE (CONTINUED)
BASE_SHIFT[3:0]
Data Scaling Factor
32 1 0
2015 Microchip Technology Inc. DS00001621B-page 38
CAP1166
6.6.2 CONFIGURATION 2 - 44H
Bit 7 - INV_LINK_TRAN - Determines the behavior of the Linked LED Transition controls (see Section 6.29).
• ‘0’ (default) - The Linked LED Transition controls set the min duty cycle equal to the max duty cycle.
• ‘1’ - The Linked LED Transition controls will invert the touch signal. For example, a touch signal will be inverted to
a non-touched signal.
Bit 6 - ALT_POL - Determines the ALERT# pin polarity and behavior.
• ‘0’ - The ALERT# pin is active high and push-pull.
• ‘1’ (default) - The ALERT# pin is active low and open drain.
Bit 5 - BLK_PWR_CTRL - Determines whether the device will reduce power consumption while waiting between conversion
time completion and the end of the polling cycle.
• ‘0’ (default) - The device will always power down as much as possible during the time between the end of the last
conversion and the end of the polling cycle.
• ‘1’ - The device will not power down the Cap Sensor during the time between the end of the last conversion and
the end of the polling cycle.
Bit 4 - BLK_POL_MIR - Determines whether the LED Mirror Control register bits are linked to the LED Polarity bits. Setting
this bit blocks the normal behavior which is to automatically set and clear the LED Mirror Control bits when the LED
Polarity bits are set or cleared.
• ‘0’ (default) - When the LED Polarity controls are set, the corresponding LED Mirror control is automatically set.
Likewise, when the LED Polarity controls are cleared, the corresponding LED Mirror control is also cleared.
• ‘1’ - When the LED Polarity controls are set, the corresponding LED Mirror control is not automatically set.
Bit 3 - SHOW_RF_NOISE - Determines whether the Noise Status bits will show RF Noise as the only input source.
• ‘0’ (default) - The Noise Status registers will show both RF noise and low frequency EMI noise if either is detected
on a capacitive touch sensor input.
• ‘1’ - The Noise Status registers will only show RF noise if it is detected on a capacitive touch sensor input. EMI
noise will still be detected and touches will be blocked normally; however, the status bits will not be updated.
Bit 2 - DIS_RF_NOISE - Determines whether the RF noise filter is enabled. Setting this bit disables the feature.
• ‘0’ (default) - If RF noise is detected by the analog block, the delta count on the corresponding channel is set to 0.
Note that this does not require that Noise Status bits be set.
• ‘1’ - A touch is not blocked even if RF noise is detected.
Bit 0 - INT_REL_n - Controls the interrupt behavior when a release is detected on a button.
• ‘0’ (default) - An interrupt is generated when a press is detected and again when a release is detected and at the
repeat rate (if enabled - see Section 6.13).
• ‘1’ - An interrupt is generated when a press is detected and at the repeat rate but not when a release is detected.
6.7 Sensor Input Enable Registers
The Sensor Input Enable registers determine whether a capacitive touch sensor input is included in the sampling cycle.
The length of the sampling cycle is not affected by the number of sensor inputs measured.
Bit 5 - CS6_EN - Enables the CS6 input to be included during the sampling cycle.
• ‘0’ - The CS6 input is not included in the sampling cycle.
• ‘1’ (default) - The CS6 input is included in the sampling cycle.
Bit 4 - CS5_EN - Enables the CS5 input to be included during the sampling cycle.
Bit 3 - CS4_EN - Enables the CS4 input to be included during the sampling cycle.
Bit 2 - CS3_EN - Enables the CS3 input to be included during the sampling cycle.
TABLE 6-11: SENSOR INPUT ENABLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
21h R/W Sensor Input
Enable - - CS6_EN CS5_EN CS4_EN CS3_EN CS2_EN CS1_EN 3Fh
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DS00001621B-page 39 2015 Microchip Technology Inc.
Bit 1 - CS2_EN - Enables the CS2 input to be included during the sampling cycle.
Bit 0 - CS1_EN - Enables the CS1 input to be included during the sampling cycle.
6.8 Sensor Input Configuration Register
The Sensor Input Configuration Register controls timings associated with the Capacitive sensor inputs 1 - 6.
Bits 7 - 4 - MAX_DUR[3:0] - (default 1010b) - Determines the maximum time that a sensor pad is allowed to be touched
until the capacitive touch sensor input is recalibrated, as shown in Table 6-13.
Bits 3 - 0 - RPT_RATE[3:0] - (default 0100b) Determines the time duration between interrupt assertions when auto
repeat is enabled. The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-14.
TABLE 6-12: SENSOR INPUT CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
22h R/W Sensor Input
Configuration MAX_DUR[3:0] RPT_RATE[3:0] A4h
TABLE 6-13: MAX_DUR BIT DECODE
MAX_DUR[3:0]
Time Before Recalibration
32 1 0
0 0 0 0 560ms
0 0 0 1 840ms
0 0 1 0 1120ms
0 0 1 1 1400ms
0 1 0 0 1680ms
0 1 0 1 2240ms
0 1 1 0 2800ms
1 1 1 3360ms
1 0 0 0 3920ms
1 0 0 1 4480ms
1 0 1 0 5600ms (default)
1 0 1 1 6720ms
1 1 0 0 7840ms
1 1 0 1 8906ms
1 1 1 0 10080ms
1 1 1 1 11200ms
TABLE 6-14: RPT_RATE BIT DECODE
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms (default)
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms
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6.9 Sensor Input Configuration 2 Register
Bits 3 - 0 - M_PRESS[3:0] - (default 0111b) - Determines the minimum amount of time that sensor inputs configured to
use auto repeat must detect a sensor pad touch to detect a “press and hold” event. If the sensor input detects a touch
for longer than the M_PRESS[3:0] settings, a “press and hold” event is detected. If a sensor input detects a touch for
less than or equal to the M_PRESS[3:0] settings, a touch event is detected.
The resolution is 35ms the range is from 35ms to 560ms as shown in Table 6-16.
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-15: SENSOR INPUT CONFIGURATION 2 REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
23h R/W Sensor Input
Configuration 2 - - - - M_PRESS[3:0] 07h
TABLE 6-16: M_PRESS BIT DECODE
M_PRESS[3:0]
M_PRESS SETTINGS
3 21 0
0 0 0 0 35ms
0 0 0 1 70ms
0 0 1 0 105ms
0 0 1 1 140ms
0 1 0 0 175ms
0 1 0 1 210ms
0 1 1 0 245ms
0 1 1 1 280ms (default)
1 0 0 0 315ms
1 0 0 1 350ms
1 0 1 0 385ms
1 0 1 1 420ms
1 1 0 0 455ms
1 1 0 1 490ms
1 1 1 0 525ms
1 1 1 1 560ms
TABLE 6-14: RPT_RATE BIT DECODE (CONTINUED)
RPT_RATE[3:0]
Interrupt Repeat RATE
3 21 0
CAP1166
DS00001621B-page 41 2015 Microchip Technology Inc.
6.10 Averaging and Sampling Configuration Register
The Averaging and Sampling Configuration register controls the number of samples taken and the total sensor input
cycle time for all active sensor inputs while the device is functioning in Active state.
Bits 6 - 4 - AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor cycle
as shown in Table 6-18. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
For example, if CS1, CS2, and CS3 are sampled during the sensor cycle, and the AVG[2:0] bits are set to take 4 samples
per channel, then the full sensor cycle will be: CS1, CS1, CS1, CS1, CS2, CS2, CS2, CS2, CS3, CS3, CS3, CS3.
Bits 3 - 2 - SAMP_TIME[1:0] - Determines the time to take a single sample as shown in Table 6-19.
Bits 1 - 0 - CYCLE_TIME[1:0] - Determines the overall cycle time for all measured channels during normal operation as
shown in Table 6-20. All measured channels are sampled at the beginning of the cycle time. If additional time is remaining,
then the device is placed into a lower power state for the remaining duration of the cycle.
TABLE 6-17: AVERAGING AND SAMPLING CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
24h R/W Averaging and
Sampling Config AVG[2:0] SAMP_TIME[1:0] CYCLE_TIME
[1:0] 39h
TABLE 6-18: AVG BIT DECODE
AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
TABLE 6-19: SAMP_TIME BIT DECODE
SAMP_TIME[1:0]
Sample Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-20: CYCLE_TIME BIT DECODE
CYCLE_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
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APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The AVG[2:0] bits will take priority so that if more samples
are required than would normally be allowed during the cycle time, the cycle time will be
extended as necessary to accommodate the number of samples to be measured.
6.11 Calibration Activate Register
The Calibration Activate register forces the respective sensor inputs to be re-calibrated affecting both the analog and
digital blocks. During the re-calibration routine, the sensor inputs will not detect a press for up to 600ms and the Sensor
Input Base Count register values will be invalid. During this time, any press on the corresponding sensor pads will invalidate
the re-calibration. When finished, the CALX[9:0] bits will be updated (see Section 6.39).
When the corresponding bit is set, the device will perform the calibration and the bit will be automatically cleared once
the re-calibration routine has finished.
Bit 5 - CS6_CAL - When set, the CS6 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 4 - CS5_CAL - When set, the CS5 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 3 - CS4_CAL - When set, the CS4 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 2 - CS3_CAL - When set, the CS3 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 1 - CS2_CAL - When set, the CS2 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
Bit 0 - CS1_CAL - When set, the CS1 input is re-calibrated. This bit is automatically cleared once the sensor input has
been re-calibrated successfully.
6.12 Interrupt Enable Register
The Interrupt Enable register determines whether a sensor pad touch or release (if enabled) causes the interrupt pin to
be asserted.
Bit 5 - CS6_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS6 (associated with the CS6
status bit).
• ‘0’ - The interrupt pin will not be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
• ‘1’ (default) - The interrupt pin will be asserted if a touch is detected on CS6 (associated with the CS6 status bit).
Bit 4 - CS5_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS5 (associated with the CS5
status bit).
Bit 3 - CS4_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS4 (associated with the CS4
status bit).
Bit 2 - CS3_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS3 (associated with the CS3
status bit).
Bit 1 - CS2_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS2 (associated with the CS2
status bit).
TABLE 6-21: CALIBRATION ACTIVATE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
26h R/W Calibration
Activate - - CS6_
CAL
CS5_
CAL
CS4_
CAL
CS3_
CAL
CS2_
CAL
CS1_
CAL 00h
TABLE 6-22: INTERRUPT ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
27h R/W Interrupt
Enable - - CS6_
INT_EN
CS5_
INT_EN
CS4_
INT_EN
CS3_
INT_EN
CS2_
INT_EN
CS1_
INT_EN 3Fh
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DS00001621B-page 43 2015 Microchip Technology Inc.
Bit 0 - CS1_INT_EN - Enables the interrupt pin to be asserted if a touch is detected on CS1 (associated with the CS1
status bit).
6.13 Repeat Rate Enable Register
The Repeat Rate Enable register enables the repeat rate of the sensor inputs as described in Section 5.6.1.
Bit 5 - CS6_RPT_EN - Enables the repeat rate for capacitive touch sensor input 6.
• ‘0’ - The repeat rate for CS6 is disabled. It will only generate an interrupt when a touch is detected and when a
release is detected no matter how long the touch is held for.
• ‘1’ (default) - The repeat rate for CS6 is enabled. In the case of a “touch” event, it will generate an interrupt when a
touch is detected and a release is detected (as determined by the INT_REL_n bit - see Section 6.6). In the case of
a “press and hold” event, it will generate an interrupt when a touch is detected and at the repeat rate so long as
the touch is held.
Bit 4 - CS5_RPT_EN - Enables the repeat rate for capacitive touch sensor input 5.
Bit 3 - CS4_RPT_EN - Enables the repeat rate for capacitive touch sensor input 4.
Bit 2 - CS3_RPT_EN - Enables the repeat rate for capacitive touch sensor input 3.
Bit 1 - CS2_RPT_EN - Enables the repeat rate for capacitive touch sensor input 2.
Bit 0 - CS1_RPT_EN - Enables the repeat rate for capacitive touch sensor input 1.
6.14 Multiple Touch Configuration Register
The Multiple Touch Configuration register controls the settings for the multiple touch detection circuitry. These settings
determine the number of simultaneous buttons that may be pressed before additional buttons are blocked and the MULT
status bit is set.
Bit 7 - MULT_BLK_EN - Enables the multiple button blocking circuitry.
• ‘0’ - The multiple touch circuitry is disabled. The device will not block multiple touches.
• ‘1’ (default) - The multiple touch circuitry is enabled. The device will flag the number of touches equal to programmed
multiple touch threshold and block all others. It will remember which sensor inputs are valid and block all
others until that sensor pad has been released. Once a sensor pad has been released, the N detected touches
(determined via the cycle order of CS1 - CS6) will be flagged and all others blocked.
Bits 3 - 2 - B_MULT_T[1:0] - Determines the number of simultaneous touches on all sensor pads before a Multiple Touch
Event is detected and sensor inputs are blocked. The bit decode is given by Table 6-25.
TABLE 6-23: REPEAT RATE ENABLE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
28h R/W Repeat Rate
Enable - - CS6_
RPT_EN
CS5_
RPT_EN
CS4_
RPT_EN
CS3_
RPT_EN
CS2_
RPT_EN
CS1_
RPT_EN 3Fh
TABLE 6-24: MULTIPLE TOUCH CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Ah R/W Multiple Touch
Config
MULT_
BLK_
EN
- - - B_MULT_T[1:0] - - 80h
TABLE 6-25: B_MULT_T BIT DECODE
B_MULT_T[1:0]
Number of Simultaneous Touches
1 0
0 0 1 (default)
01 2
10 3
11 4
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6.15 Multiple Touch Pattern Configuration Register
The Multiple Touch Pattern Configuration register controls the settings for the multiple touch pattern detection circuitry.
This circuitry works like the multiple touch detection circuitry with the following differences:
1. The detection threshold is a percentage of the touch detection threshold as defined by the MTP_TH[1:0] bits
whereas the multiple touch circuitry uses the touch detection threshold.
2. The MTP detection circuitry either will detect a specific pattern of sensor inputs as determined by the Multiple
Touch Pattern register settings or it will use the Multiple Touch Pattern register settings to determine a minimum
number of sensor inputs that will cause the MTP circuitry to flag an event. When using pattern recognition mode,
if all of the sensor inputs set by the Multiple Touch Pattern register have a delta count greater than the MTP
threshold or have their corresponding Noise Flag Status bits set, the MTP bit will be set. When using the absolute
number mode, if the number of sensor inputs with thresholds above the MTP threshold or with Noise Flag Status
bits set is equal to or greater than this number, the MTP bit will be set.
3. When an MTP event occurs, all touches are blocked and an interrupt is generated.
4. All sensor inputs will remain blocked so long as the requisite number of sensor inputs are above the MTP threshold
or have Noise Flag Status bits set. Once this condition is removed, touch detection will be restored. Note that
the MTP status bit is only cleared by writing a ‘0’ to the INT bit once the condition has been removed.
Bit 7 - MTP_EN - Enables the multiple touch pattern detection circuitry.
• ‘0’ (default) - The MTP detection circuitry is disabled.
• ‘1’ - The MTP detection circuitry is enabled.
Bits 3-2 - MTP_TH[1:0] - Determine the MTP threshold, as shown in Table 6-27. This threshold is a percentage of sensor
input threshold (see Section 6.18, "Sensor Input Threshold Registers") when the device is in the Fully Active state or of
the standby threshold (see Section 6.23, "Standby Threshold Register") when the device is in the Standby state.
Bit 1 - COMP_PTRN - Determines whether the MTP detection circuitry will use the Multiple Touch Pattern register as a
specific pattern of sensor inputs or as an absolute number of sensor inputs.
• ‘0’ (default) - The MTP detection circuitry will use the Multiple Touch Pattern register bit settings as an absolute
minimum number of sensor inputs that must be above the threshold or have Noise Flag Status bits set. The number
will be equal to the number of bits set in the register.
• ‘1’ - The MTP detection circuitry will use pattern recognition. Each bit set in the Multiple Touch Pattern register
indicates a specific sensor input that must have a delta count greater than the MTP threshold or have a Noise Flag
Status bit set. If the criteria are met, the MTP status bit will be set.
Bit 0 - MTP_ALERT - Enables an interrupt if an MTP event occurs. In either condition, the MTP status bit will be set.
• ‘0’ (default) - If an MTP event occurs, the ALERT# pin is not asserted.
• ‘1’ - If an MTP event occurs, the ALERT# pin will be asserted.
TABLE 6-26: MULTIPLE TOUCH PATTERN CONFIGURATION
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Bh R/W Multiple Touch
Pattern Config MTP_ EN - - MTP_TH[1:0] COMP_
PTRN
MTP_
ALERT 00h
TABLE 6-27: MTP_TH BIT DECODE
MTP_TH[1:0]
Threshold Divide Setting
1 0
0 0 12.5% (default)
0 1 25%
1 0 37.5%
1 1 100%
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DS00001621B-page 45 2015 Microchip Technology Inc.
6.16 Multiple Touch Pattern Register
The Multiple Touch Pattern register acts as a pattern to identify an expected sensor input profile for diagnostics or other
significant events. There are two methods for how the Multiple Touch Pattern register is used: as specific sensor inputs
or number of sensor input that must exceed the MTP threshold or have Noise Flag Status bits set. Which method is used
is based on the COMP_PTRN bit (see Section 6.15). The methods are described below.
1. Specific Sensor Inputs: If, during a single polling cycle, the specific sensor inputs above the MTP threshold or
with Noise Flag Status bits set match those bits set in the Multiple Touch Pattern register, an MTP event is
flagged.
2. Number of Sensor Inputs: If, during a single polling cycle, the number of sensor inputs with a delta count above
the MTP threshold or with Noise Flag Status bits set is equal to or greater than the number of pattern bits set, an
MTP event is flagged.
Bit 5 - CS6_PTRN - Determines whether CS6 is considered as part of the Multiple Touch Pattern.
• ‘0’ - CS6 is not considered a part of the pattern.
• ‘1’ - CS6 is considered a part of the pattern or the absolute number of sensor inputs that must have a delta count
greater than the MTP threshold or have the Noise Flag Status bit set is increased by 1.
Bit 4 - CS5_PTRN - Determines whether CS5 is considered as part of the Multiple Touch Pattern.
Bit 3 - CS4_PTRN - Determines whether CS4 is considered as part of the Multiple Touch Pattern.
Bit 2 - CS3_PTRN - Determines whether CS3 is considered as part of the Multiple Touch Pattern.
Bit 1 - CS2_PTRN - Determines whether CS2 is considered as part of the Multiple Touch Pattern.
Bit 0 - CS1_PTRN - Determines whether CS1 is considered as part of the Multiple Touch Pattern.
6.17 Recalibration Configuration Register
The Recalibration Configuration register controls the automatic re-calibration routine settings as well as advanced controls
to program the Sensor Input Threshold register settings.
Bit 7 - BUT_LD_TH - Enables setting all Sensor Input Threshold registers by writing to the Sensor Input 1 Threshold
register.
• ‘0’ - Each Sensor Input X Threshold register is updated individually.
• ‘1’ (default) - Writing the Sensor Input 1 Threshold register will automatically overwrite the Sensor Input Threshold
registers for all sensor inputs (Sensor Input Threshold 1 through Sensor Input Threshold 6). The individual Sensor
Input X Threshold registers (Sensor Input 2 Threshold through Sensor Input 6 Threshold) can be individually
updated at any time.
Bit 6 - NO_CLR_INTD - Controls whether the accumulation of intermediate data is cleared if the noise status bit is set.
• ‘0’ (default) - The accumulation of intermediate data is cleared if the noise status bit is set.
• ‘1’ - The accumulation of intermediate data is not cleared if the noise status bit is set.
APPLICATION NOTE: Bits 5 and 6 should both be set to the same value. Either both should be set to ‘0’ or both
should be set to ‘1’.
Bit 5 - NO_CLR_NEG - Controls whether the consecutive negative delta counts counter is cleared if the noise status bit
is set.
TABLE 6-28: MULTIPLE TOUCH PATTERN REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Dh R/W Multiple
Touch Pattern - - CS6_
PTRN
CS5_
PTRN
CS4_
PTRN
CS3_
PTRN
CS2_
PTRN
CS1_
PTRN 3Fh
TABLE 6-29: RECALIBRATION CONFIGURATION REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
2Fh R/W Recalibration
Configuration
BUT_
LD_TH
NO_
CLR_
INTD
NO_
CLR_
NEG
NEG_DELTA_
CNT[1:0] CAL_CFG[2:0] 8Ah
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• ‘0’ (default) - The consecutive negative delta counts counter is cleared if the noise status bit is set.
• ‘1’ - The consecutive negative delta counts counter is not cleared if the noise status bit is set.
Bits 4 - 3 - NEG_DELTA_CNT[1:0] - Determines the number of negative delta counts necessary to trigger a digital recalibration
as shown in Table 6-30.
Bits 2 - 0 - CAL_CFG[2:0] - Determines the update time and number of samples of the automatic re-calibration routine.
The settings apply to all sensor inputs universally (though individual sensor inputs can be configured to support re-calibration
- see Section 6.11).
Note 6-1 Recalibration Samples refers to the number of samples that are measured and averaged before the
Base Count is updated however does not control the base count update period.
Note 6-2 Update Time refers to the amount of time (in polling cycle periods) that elapses before the Base
Count is updated. The time will depend upon the number of channels active, the averaging setting,
and the programmed cycle time.
TABLE 6-30: NEG_DELTA_CNT BIT DECODE
NEG_DELTA_CNT[1:0]
Number of Consecutive Negative Delta Count Values
1 0
00 8
0 1 16 (default)
1 0 32
1 1 None (disabled)
TABLE 6-31: CAL_CFG BIT DECODE
CAL_CFG[2:0] Recalibration Samples
(see Note 6-1)
Update Time (see
Note 6-2) 210
0 0 0 16 16
0 0 1 32 32
0 1 0 64 64 (default)
0 1 1 128 128
1 0 0 256 256
1 0 1 256 1024
1 1 0 256 2048
1 1 1 256 4096
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DS00001621B-page 47 2015 Microchip Technology Inc.
6.18 Sensor Input Threshold Registers
The Sensor Input Threshold registers store the delta threshold that is used to determine if a touch has been detected.
When a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with
a touch. If the sensor input change exceeds the threshold settings, a touch is detected.
When the BUT_LD_TH bit is set (see Section 6.17 - bit 7), writing data to the Sensor Input 1 Threshold register will
update all of the sensor input threshold registers (31h - 35h inclusive).
6.19 Sensor Input Noise Threshold Register
The Sensor Input Noise Threshold register controls the value of a secondary internal threshold to detect noise and
improve the automatic recalibration routine. If a capacitive touch sensor input exceeds the Sensor Input Noise Threshold
but does not exceed the sensor input threshold, it is determined to be caused by a noise spike. That sample is not used
by the automatic re-calibration routine. This feature can be disabled by setting the DIS_DIG_NOISE bit.
Bits 1-0 - CS1_BN_TH[1:0] - Controls the noise threshold for all capacitive touch sensor inputs, as shown in Table 6-34.
The threshold is proportional to the threshold setting.
6.20 Standby Channel Register
TABLE 6-32: SENSOR INPUT THRESHOLD REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
30h R/W Sensor Input 1
Threshold - 64 32 16 8 4 2 1 40h
31h R/W Sensor Input 2
Threshold - 64 32 16 8 4 2 1 40h
32h R/W Sensor Input 3
Threshold - 64 32 16 8 4 2 1 40h
33h R/W Sensor Input 4
Threshold - 64 32 16 8 4 2 1 40h
34h R/W Sensor Input 5
Threshold - 64 32 16 8 4 2 1 40h
35h R/W Sensor Input 6
Threshold - 64 32 16 8 4 2 1 40h
TABLE 6-33: SENSOR INPUT NOISE THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
38h R/W Sensor Input
Noise Threshold CS_BN_TH [1:0] 01h
TABLE 6-34: CSX_BN_TH BIT DECODE
CS_BN_TH[1:0]
Percent Threshold Setting
1 0
0 0 25%
0 1 37.5% (default)
1 0 50%
1 1 62.5%
TABLE 6-35: STANDBY CHANNEL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
40h R/W Standby Channel - - CS6_
STBY
CS5_
STBY
CS4_
STBY
CS3_
STBY
CS2_
STBY
CS1_
STBY 00h
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The Standby Channel register controls which (if any) capacitive touch sensor inputs are active during Standby.
Bit 5 - CS6_STBY - Controls whether the CS6 channel is active in Standby.
• ‘0’ (default) - The CS6 channel not be sampled during Standby mode.
• ‘1’ - The CS6 channel will be sampled during Standby Mode. It will use the Standby threshold setting, and the
standby averaging and sensitivity settings.
Bit 4 - CS5_STBY - Controls whether the CS5 channel is active in Standby.
Bit 3 - CS4_STBY - Controls whether the CS4 channel is active in Standby.
Bit 2 - CS3_STBY - Controls whether the CS3 channel is active in Standby.
Bit 1 - CS2_STBY - Controls whether the CS2 channel is active in Standby.
Bit 0 - CS1_STBY - Controls whether the CS1 channel is active in Standby.
6.21 Standby Configuration Register
The Standby Configuration register controls averaging and cycle time for those sensor inputs that are active in Standby.
This register is useful for detecting proximity on a small number of sensor inputs as it allows the user to change averaging
and sample times on a limited number of sensor inputs and still maintain normal functionality in the fully active
state.
Bit 7 - AVG_SUM - Determines whether the active sensor inputs will average the programmed number of samples or
whether they will accumulate for the programmed number of samples.
• ‘0’ - (default) - The active sensor input delta count values will be based on the average of the programmed number
of samples when compared against the threshold.
• ‘1’ - The active sensor input delta count values will be based on the summation of the programmed number of
samples when compared against the threshold. This bit should only be set when performing proximity detection as
a physical touch will overflow the delta count registers and may result in false readings.
Bits 6 - 4 - STBY_AVG[2:0] - Determines the number of samples that are taken for all active channels during the sensor
cycle as shown in Table 6-37. All samples are taken consecutively on the same channel before the next channel is sampled
and the result is averaged over the number of samples measured before updating the measured results.
Bit 3-2 - STBY SAMP_TIME[1:0] - Determines the time to take a single sample when the device is in Standby as shown
in Table 6-38.
TABLE 6-36: STANDBY CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
41h R/W Standby Configuration
AVG_
SUM STBY_AVG[2:0] STBY_SAMP_
TIME[1:0]
STBY_CY_TIME
[1:0] 39h
TABLE 6-37: STBY_AVG BIT DECODE
STBY_AVG[2:0] Number of Samples Taken per
Measurement 2 10
0 0 0 1
0 01 2
0 10 4
0 1 1 8 (default)
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
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DS00001621B-page 49 2015 Microchip Technology Inc.
Bits 1 - 0 - STBY_CY_TIME[2:0] - Determines the overall cycle time for all measured channels during standby operation
as shown in Table 6-39. All measured channels are sampled at the beginning of the cycle time. If additional time is
remaining, the device is placed into a lower power state for the remaining duration of the cycle.
APPLICATION NOTE: The programmed cycle time is only maintained if the total averaging time for all samples is
less than the programmed cycle. The STBY_AVG[2:0] bits will take priority so that if more
samples are required than would normally be allowed during the cycle time, the cycle time
will be extended as necessary to accommodate the number of samples to be measured.
6.22 Standby Sensitivity Register
The Standby Sensitivity register controls the sensitivity for sensor inputs that are active in Standby.
Bits 2 - 0 - STBY_SENSE[2:0] - Controls the sensitivity for sensor inputs that are active in Standby. The sensitivity settings
act to scale the relative delta count value higher or lower based on the system parameters. A setting of 000b is the
most sensitive while a setting of 111b is the least sensitive. At the more sensitive settings, touches are detected for a
smaller delta C corresponding to a “lighter” touch. These settings are more sensitive to noise however and a noisy environment
may flag more false touches than higher sensitivity levels.
APPLICATION NOTE: A value of 128x is the most sensitive setting available. At the most sensitivity settings, the
MSB of the Delta Count register represents 64 out of ~25,000 which corresponds to a touch
of approximately 0.25% of the base capacitance (or a ΔC of 25fF from a 10pF base
capacitance). Conversely a value of 1x is the least sensitive setting available. At these
settings, the MSB of the Delta Count register corresponds to a delta count of 8192 counts
out of ~25,000 which corresponds to a touch of approximately 33% of the base capacitance
(or a ΔC of 3.33pF from a 10pF base capacitance).
TABLE 6-38: STBY_SAMP_TIME BIT DECODE
STBY_SAMP_TIME[1:0]
Sampling Time
1 0
0 0 320us
0 1 640us
1 0 1.28ms (default)
1 1 2.56ms
TABLE 6-39: STBY_CY_TIME BIT DECODE
STBY_CY_TIME[1:0]
Overall Cycle Time
1 0
0 0 35ms
0 1 70ms (default)
1 0 105ms
1 1 140ms
TABLE 6-40: STANDBY SENSITIVITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
42h R/W Standby Sensitivity
- - - - - STBY_SENSE[2:0] 02h
TABLE 6-41: STBY_SENSE BIT DECODE
STBY_SENSE[2:0]
Sensitivity Multiplier
210
0 0 0 128x (most sensitive)
0 0 1 64x
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6.23 Standby Threshold Register
The Standby Threshold register stores the delta threshold that is used to determine if a touch has been detected. When
a touch occurs, the input signal of the corresponding sensor pad changes due to the capacitance associated with a
touch. If the sensor input change exceeds the threshold settings, a touch is detected.
6.24 Sensor Input Base Count Registers
The Sensor Input Base Count registers store the calibrated “Not Touched” input value from the capacitive touch sensor
inputs. These registers are periodically updated by the re-calibration routine.
The routine uses an internal adder to add the current count value for each reading to the sum of the previous readings
until sample size has been reached. At this point, the upper 16 bits are taken and used as the Sensor Input Base Count.
The internal adder is then reset and the re-calibration routine continues.
The data presented is determined by the BASE_SHIFT[3:0] bits (see Section 6.5).
6.25 LED Output Type Register
0 1 0 32x (default)
0 1 1 16x
1 0 0 8x
1 0 1 4x
1 1 0 2x
1 1 1 1x - (least sensitive)
TABLE 6-42: STANDBY THRESHOLD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
43h R/W Standby Threshold
- 64 32 16 8 4 2 1 40h
TABLE 6-43: SENSOR INPUT BASE COUNT REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
50h R Sensor Input 1
Base Count 128 64 32 16 8 4 2 1 C8h
51h R Sensor Input 2
Base Count 128 64 32 16 8 4 2 1 C8h
52h R Sensor Input 3
Base Count 128 64 32 16 8 4 2 1 C8h
53h R Sensor Input 4
Base Count 128 64 32 16 8 4 2 1 C8h
54h R Sensor Input 5
Base Count 128 64 32 16 8 4 2 1 C8h
55h R Sensor Input 6
Base Count 128 64 32 16 8 4 2 1 C8h
TABLE 6-44: LED OUTPUT TYPE REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
71h R/W LED Output
Type - - LED6_
OT
LED5_
OT
LED4_
OT
LED3_
OT
LED2_
OT
LED1_
OT 00h
TABLE 6-41: STBY_SENSE BIT DECODE (CONTINUED)
STBY_SENSE[2:0]
Sensitivity Multiplier
210
CAP1166
DS00001621B-page 51 2015 Microchip Technology Inc.
The LED Output Type register controls the type of output for the LED pins. Each pin is controlled by a single bit. Refer
to application note 21.4 CAP1166Family LED Configuration Options for more information about implementing LEDs.
Bit 5 - LED6_OT - Determines the output type of the LED6 pin.
• ‘0’ (default) - The LED6 pin is an open-drain output with an external pull-up resistor. When the appropriate pin is
set to the “active” state (logic ‘1’), the pin will be driven low. Conversely, when the pin is set to the “inactive” state
(logic ‘0’), then the pin will be left in a High Z state and pulled high via an external pull-up resistor.
• ‘1’ - The LED6 pin is a push-pull output. When driving a logic ‘1’, the pin is driven high. When driving a logic ‘0’, the
pin is driven low.
Bit 4 - LED5_OT - Determines the output type of the LED5 pin.
Bit 3 - LED4_OT - Determines the output type of the LED4 pin.
Bit 2 - LED3_OT - Determines the output type of the LED3 pin.
Bit 1 - LED2_OT - Determines the output type of the LED2 pin.
Bit 0 - LED1_OT - Determines the output type of the LED1 pin.
6.26 Sensor Input LED Linking Register
The Sensor Input LED Linking register controls whether a capacitive touch sensor input is linked to an LED output. If
the corresponding bit is set, then the appropriate LED output will change states defined by the LED Behavior controls
(see Section 6.31) in response to the capacitive touch sensor input.
Bit 5 - CS6_LED6 - Links the LED6 output to a detected touch on the CS6 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
• ‘0’ (default) - The LED6 output is not associated with the CS6 input. If a touch is detected on the CS6 input, the
LED will not automatically be actuated. The LED is enabled and controlled via the LED Output Control register
(see Section 6.28) and the LED Behavior registers (see Section 6.31).
• ‘1’ - The LED6 output is associated with the CS6 input. If a touch is detected on the CS6 input, the LED will be
actuated and behave as defined in Table 6-52.
Bit 4 - CS5_LED5 - Links the LED5 output to a detected touch on the CS5 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
Bit 3 - CS4_LED4 - Links the LED4 output to a detected touch on the CS4 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
Bit 2 - CS3_LED3 - Links the LED3 output to a detected touch on the CS3 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
Bit 1 - CS2_LED2 - Links the LED2 output to a detected touch on the CS2 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
Bit 0 - CS1_LED1 - Links the LED1 output to a detected touch on the CS1 sensor input. When a touch is detected, the
LED is actuated and will behave as determined by the LED Behavior controls.
6.27 LED Polarity Register
TABLE 6-45: SENSOR INPUT LED LINKING REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
72h R/W Sensor Input
LED Linking
- - CS6_
LED6
CS5_
LED5
CS4_
LED4
CS3_
LED3
CS2_
LED2
CS1_
LED1
00h
TABLE 6-46: LED POLARITY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
73h R/W LED Polarity - - LED6_
POL
LED5_
POL
LED4_
POL
LED3_
POL
LED2_
POL
LED1_
POL 00h
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The LED Polarity register controls the logical polarity of the LED outputs. When these bits are set or cleared, the corresponding
LED Mirror controls are also set or cleared (unless the BLK_POL_MIR bit is set - see Section 6.6, "Configuration
Registers"). Table 6-48, "LED Polarity Behavior" shows the interaction between the polarity controls, output
controls, and relative brightness.
APPLICATION NOTE: The polarity controls determine the final LED pin drive. A touch on a linked capacitive touch
sensor input is treated in the same way as the LED Output Control bit being set to a logic ‘1’.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’ then the LED will be on and that the CAP1166 LED pin is sinking the LED current.
Conversely, if the LED pin is driven to a logic ‘1’, the LED will be off and there is no current
flow. See Figure 5-1, "System Diagram for CAP1166".
APPLICATION NOTE: This application note applies when the LED polarity is inverted (LEDx_POL = ‘0’). For LED
operation, the duty cycle settings determine the % of time that the LED pin will be driven to
a logic ‘0’ state in. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven low (i.e. maximum % of time that the LED is on) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven low (i.e. minimum
% of time that the LED is on). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at the minimum duty cycle setting.
Breathe operations will ramp the duty cycle from the minimum duty cycle to the maximum
duty cycle.
APPLICATION NOTE: This application note applies when the LED polarity is non-inverted (LEDx_POL = ‘1’). For
LED operation, the duty cycle settings determine the % of time that the LED pin will be driven
to a logic ‘1’ state. The Max Duty Cycle settings define the maximum % of time that the LED
pin will be driven high (i.e. maximum % of time that the LED is off) while the Min Duty Cycle
settings determine the minimum % of time that the LED pin will be driven high (i.e. minimum
% of time that the LED is off). When there is no touch detected or the LED Output Control
register bit is at a logic ‘0’, the LED output will be driven at 100 minus the minimum duty
cycle setting. Breathe operations will ramp the duty cycle from 100 minus the minimum duty
cycle to 100 minus the maximum duty cycle.
APPLICATION NOTE: The LED Mirror controls (see Section 6.30, "LED Mirror Control Register") work with the
polarity controls with respect to LED brightness but will not have a direct effect on the output
pin drive.
Bit 5 - LED6_POL - Determines the polarity of the LED6 output.
• ‘0’ (default) - The LED6 output is inverted. For example, a setting of ‘1’ in the LED Output Control register will
cause the LED pin output to be driven to a logic ‘0’.
• ‘1’ - The LED6 output is non-inverted. For example, a setting of ‘1’ in the LED Output Control register will cause
the LED pin output to be driven to a logic ‘1’ or left in the high-z state as determined by its output type.
Bit 4 - LED5_POL - Determines the polarity of the LED5 output.
Bit 3 - LED4_POL - Determines the polarity of the LED4 output.
Bit 2 - LED3_POL - Determines the polarity of the LED3 output.
Bit 1 - LED2_POL - Determines the polarity of the LED2 output.
Bit 0 - LED1_POL - Determines the polarity of the LED1 output.
6.28 LED Output Control Register
The LED Output Control Register controls the output state of the LED pins that are not linked to sensor inputs.
TABLE 6-47: LED OUTPUT CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
74h R/W LED Output
Control - - LED6_
DR
LED5_
DR
LED4_
DR
LED3_
DR
LED2_
DR
LED1_
DR 00h
CAP1166
DS00001621B-page 53 2015 Microchip Technology Inc.
The LED Polarity Control Register will determine the non actuated state of the LED pins. The actuated LED behavior is
determined by the LED behavior controls (see Section 6.31, "LED Behavior Registers").
Table 6-48 shows the interaction between the polarity controls, output controls, and relative brightness.
Bit 5 - LED6_DR - Determines whether LED6 output is driven high or low.
• ‘0’ (default) - The LED6 output is driven at the minimum duty cycle or not actuated.
• ‘1’ - The LED6 output is driven at the maximum duty cycle or is actuated.
Bit 4 - LED5_DR - Determines whether LED5 output is driven high or low.
Bit 3 - LED4_DR - Determines whether LED4 output is driven high or low.
Bit 2 - LED3_DR - Determines whether LED3 output is driven high or low.
Bit 1 - LED2_DR - Determines whether LED2 output is driven high or low.
Bit 0 - LED1_DR - Determines whether LED1 output is driven high or low.
6.29 Linked LED Transition Control Register
The Linked LED Transition Control register controls the LED drive when the LED is linked to a capacitive touch sensor
input. These controls work in conjunction with the INV_LINK_TRAN bit (see Section 6.6.2, "Configuration 2 - 44h") to
create smooth transitions from host control to linked LEDs.
Note: If an LED is linked to a sensor input in the Sensor Input LED Linking Register (Section 6.26, "Sensor Input
LED Linking Register"), the corresponding bit in the LED Output Control Register is ignored (i.e. a linked
LED cannot be host controlled).
TABLE 6-48: LED POLARITY BEHAVIOR
LED Output
Control
Register or
Touch
Polarity Max Duty Min Duty Brightness LED Appearance
0 inverted (‘0’) not used
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
min duty cycle
on at min duty
cycle
1 inverted (‘0’)
maximum % of time
that the LED is on
(logic 0)
minimum % of time
that the LED is on
(logic 0)
maximum brightness at
max duty cycle. Brightness
ramps from min
duty cycle to max duty
cycle
according to LED
behavior
0 non-inverted
(‘1’) not used
minimum % of time
that the LED is off
(logic 1)
maximum brightness at
100 minus min duty
cycle.
on at 100 - min
duty cycle
1 non-inverted
(‘1’)
maximum % of time
that the LED is off
(logic 1)
minimum % of time
that the LED is off
(logic 1)
For Direct behavior,
maximum brightness is
100 minus max duty
cycle. When breathing,
max brightness is
100 minus min duty
cycle. Brightness
ramps from 100 - min
duty cycle to 100 - max
duty cycle.
according to LED
behavior
TABLE 6-49: LINKED LED TRANSITION CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
77h R/W Linked LED Transition
Control - - LED6_
LTRAN
LED5_
LTRAN
LED4_
LTRAN
LED3_
LTRAN
LED2_
LTRAN
LED1_
LTRAN 00h
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Bit 5 - LED6_LTRAN - Determines the transition effect when LED6 is linked to CS6.
• ‘0’ (default) - When the LED output control bit for LED6 is ‘1’, and then LED6 is linked to CS6 and no touch is
detected, the LED will change states.
• ‘1’ - If the INV_LINK_TRAN bit is ‘1’, when the LED output control bit for CS6 is ‘1’, and then CS6 is linked to LED6
and no touch is detected, the LED will not change states. In addition, the LED state will change when the sensor
pad is touched. If the INV_LINK_TRAN bit is ‘0’, when the LED output control bit for CS6 is ‘1’, and then CS6 is
linked to LED6 and no touch is detected, the LED will not change states. However, the LED state will not change
when the sensor pad is touched.
APPLICATION NOTE: If the LED behavior is not “Direct” and the INV_LINK_TRAN bit it ‘0’, the LED will not perform
as expected when the LED6_LTRAN bit is set to ‘1’. Therefore, if breathe and pulse
behaviors are used, set the INV_LINK_TRAN bit to ‘1’.
Bit 4 - LED5_LTRAN - Determines the transition effect when LED5 is linked to CS5.
Bit 3 - LED4_LTRAN - Determines the transition effect when LED4 is linked to CS4.
Bit 2 - LED3_LTRAN - Determines the transition effect when LED3 is linked to CS3.
Bit 1 - LED2_LTRAN - Determines the transition effect when LED2 is linked to CS2.
Bit 0 - LED1_LTRAN - Determines the transition effect when LED1 is linked to CS1.
6.30 LED Mirror Control Register
The LED Mirror Control Registers determine the meaning of duty cycle settings when polarity is non-inverted for each
LED channel. When the polarity bit is set to ‘1’ (non-inverted), to obtain correct steps for LED ramping, pulse, and
breathe behaviors, the min and max duty cycles need to be relative to 100%, rather than the default, which is relative
to 0%.
APPLICATION NOTE: The LED drive assumes that the LEDs are configured such that if the LED pin is driven to
a logic ‘0’, the LED will be on and the CAP1166 LED pin is sinking the LED current. When
the polarity bit is set to ‘1’, it is considered non-inverted. For systems using the opposite LED
configuration, mirror controls would apply when the polarity bit is ‘0’.
These bits are changed automatically if the corresponding LED Polarity bit is changed (unless the BLK_POL_MIR bit is
set - see Section 6.6).
Bit 5 - LED6_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
• ‘0’ (default) - The duty cycle settings are determined relative to 0% and are determined directly with the settings.
• ‘1’ - The duty cycle settings are determined relative to 100%.
Bit 4 - LED5_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
Bit 3 - LED4_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
Bit 2 - LED3_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
Bit 1 - LED2_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
Bit 0 - LED1_MIR_EN - Determines whether the duty cycle settings are “biased” relative to 0% or 100% duty cycle.
TABLE 6-50: LED MIRROR CONTROL REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
79h R/W LED Mirror Control
- -
LED6_
MIR _
EN
LED5_
MIR _
EN
LED4_M
IR_
EN
LED3_
MIR_
EN
LED2_
MIR _
EN
LED1_
MIR _
EN
00h
CAP1166
DS00001621B-page 55 2015 Microchip Technology Inc.
6.31 LED Behavior Registers
The LED Behavior registers control the operation of LEDs. Each LED pin is controlled by a 2-bit field and the behavior
is determined by whether the LED is linked to a capacitive touch sensor input or not.
If the corresponding LED output is linked to a capacitive touch sensor input, the appropriate behavior will be enabled /
disabled based on touches and releases.
If the LED output is not associated with a capacitive touch sensor input, the appropriate behavior will be enabled / disabled
by the LED Output Control register. If the respective LEDx_DR bit is set to a logic ‘1’, this will be associated as a
“touch”, and if the LEDx_DR bit is set to a logic ‘0’, this will be associated as a “release”.
Table 6-52, "LEDx_CTL Bit Decode" shows the behavior triggers. The defined behavior will activate when the Start Trigger
is met and will stop when the Stop Trigger is met. Note the behavior of the Breathe Hold and Pulse Release option.
The LED Polarity Control register will determine the non actuated state of the LED outputs (see Section 6.27, "LED
Polarity Register").
APPLICATION NOTE: If an LED is not linked to a capacitive touch sensor input and is breathing (via the Breathe
or Pulse behaviors), it must be unactuated and then re-actuated before changes to behavior
are processed. For example, if the LED output is breathing and the Maximum duty cycle is
changed, this change will not take effect until the LED output control register is set to ‘0’ and
then re-set to ‘1’.
APPLICATION NOTE: If an LED is not linked to the capacitive touch sensor input and configured to operate using
Pulse 1 Behavior, then the circuitry will only be actuated when the corresponding output
control bit is set. It will not check the bit condition until the Pulse 1 behavior is finished. The
device will not remember if the bit was cleared and reset while it was actuated.
APPLICATION NOTE: If an LED is actuated and not linked and the desired LED behavior is changed, this new
behavior will take effect immediately; however, the first instance of the changed behavior
may act incorrectly (e.g. if changed from Direct to Pulse 1, the LED output may ‘breathe’ 4
times and then end at minimum duty cycle). LED Behaviors will operate normally once the
LED has been un-actuated and then re-actuated.
APPLICATION NOTE: If an LED is actuated and it is switched from linked to a capacitive touch sensor input to
unlinked (or vice versa), the LED will respond to the new command source immediately if
the behavior was Direct or Breathe. For Pulse behaviors, it will complete the behavior
already in progress. For example, if a linked LED was actuated by a touch and the control
is changed so that it is unlinked, it will check the status of the corresponding LED Output
Control bit. If that bit is ‘0’, then the LED will behave as if a release was detected. Likewise,
if an unlinked LED was actuated by the LED Output Control register and the control is
changed so that it is linked and no touch is detected, then the LED will behave as if a release
was detected.
6.31.1 LED BEHAVIOR 1 - 81H
Bits 7 - 6 - LED4_CTL[1:0] - Determines the behavior of LED4 as shown in Table 6-52.
Bits 5 - 4 - LED3_CTL[1:0] - Determines the behavior of LED3 as shown in Table 6-52.
Bits 3 - 2 - LED2_CTL[1:0] - Determines the behavior of LED2 as shown in Table 6-52.
Bits 1 - 0 - LED1_CTL[1:0] - Determines the behavior of LED1 as shown in Table 6-52.
6.31.2 LED BEHAVIOR 2 - 82H
Bits 3 - 2 - LED6_CTL[1:0] - Determines the behavior of LED6 as shown in Table 6-52.
Bits 1 - 0 - LED5_CTL[1:0] - Determines the behavior of LED5 as shown in Table 6-52.
TABLE 6-51: LED BEHAVIOR REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
81h R/W LED Behavior 1 LED4_CTL[1:0] LED3_CTL[1:0] LED2_CTL[1:0] LED1_CTL[1:0] 00h
82h R/W LED Behavior 2 - - - - LED6_CTL[1:0] LED5_CTL[1:0] 00h
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CAP1166
APPLICATION NOTE: The PWM frequency is determined based on the selected LED behavior, the programmed
breathe period, and the programmed min and max duty cycles. For the Direct behavior
mode, the PWM frequency is calculated based on the programmed Rise and Fall times. If
these are set at 0, then the maximum PWM frequency will be used based on the
programmed duty cycle settings.
6.32 LED Pulse 1 Period Register
The LED Pulse Period 1 register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 01b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms (24 x 32ms = 768ms). The total range is from 32ms to 4.064 seconds as shown in Table 6-54 with the
default being 1024ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
Bit 7 - ST_TRIG - Determines the start trigger for the LED Pulse behavior.
• ‘0’ (default) - The LED will Pulse when a touch is detected or the drive bit is set.
• ‘1’ - The LED will Pulse when a release is detected or the drive bit is cleared.
TABLE 6-52: LEDX_CTL BIT DECODE
LEDx_CTL
[1:0] Operation Description Start TRigger Stop Trigger
1 0
0 0 Direct The LED is driven to the programmed state
(active or inactive). See Figure 6-7
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
0 1 Pulse 1
The LED will “Pulse” a programmed number
of times. During each “Pulse” the LED will
breathe up to the maximum brightness and
back down to the minimum brightness so that
the total “Pulse” period matches the programmed
value.
Touch or Release
Detected or LED
Output Control bit
set or cleared
(see Section 6.32)
n/a
1 0 Pulse 2
The LED will “Pulse” when the start trigger is
detected. When the stop trigger is detected, it
will “Pulse” a programmable number of times
then return to its minimum brightness.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
1 1 Breathe
The LED will breathe. It will be driven with a
duty cycle that ramps up from the programmed
minimum duty cycle (default 0%) to
the programmed maximum duty cycle duty
cycle (default 100%) and then back down.
Each ramp takes up 50% of the programmed
period. The total period of each “breath” is
determined by the LED Breathe Period controls
- see Section 6.34.
Touch Detected or
LED Output Control
bit set
Release
Detected or
LED Output
Control bit
cleared
TABLE 6-53: LED PULSE 1 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
84h R/W LED Pulse 1
Period
ST_
TRIG
P1_
PER6
P1_
PER5
P1_
PER4
P1_
PER3
P1_
PER2
P1_
PER1
P1_
PER0 20h
CAP1166
DS00001621B-page 57 2015 Microchip Technology Inc.
The Pulse 1 operation is shown in Figure 6-1 when the LED output is configured for non-inverted polarity (LEDx_POL
= 1) and in Figure 6-2 for inverted polarity (LEDx_POL = 0).
.
FIGURE 6-1: Pulse 1 Behavior with Non-Inverted Polarity
FIGURE 6-2: Pulse 1 Behavior with Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
00h 0 32
01h 1 32
02h 2 64
03h 3 96
. . . . . . . . .
7Dh 125 4000
Normal – untouched
operation Normal – untouched
operation
Touch Detected or
Release Detected
(100% - Pulse 1 Max Duty Cycle) * Brightness
X pulses after touch or after release
Pulse 1 Period
(P1_PER)
(100% - Pulse 1 Min Duty Cycle) * Brightness
LED
Brightness
Normal – untouched
operation
Normal – untouched
operation
Touch Detected or
Release Detected
Pulse 1 Min Duty Cycle * Brightness
X pulses after touch or after release
Pulse Period
(P1_PER)
Pulse 1 Max Duty Cycle * Brightness
LED
Brightness
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CAP1166
6.33 LED Pulse 2 Period Register
The LED Pulse 2 Period register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 10b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 640ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
The Pulse 2 Behavior is shown in Figure 6-3 for non-inverted polarity (LEDx_POL = 1) and in Figure 6-4 for inverted
polarity (LEDx_POL = 0).
7Eh 126 4032
7Fh 127 4064
TABLE 6-55: LED PULSE 2 PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
85h R/W LED Pulse 2
Period - P2_
PER6
P2_
PER5
P2_
PER4
P2_
PER3
P2_
PER2
P2_
PER1
P2_
PER0 14h
FIGURE 6-3: Pulse 2 Behavior with Non-Inverted Polarity
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE (CONTINUED)
Setting (HEX) Setting (Decimal) Total Breathe / Pulse Period (MS)
. . .
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
(100% - Pulse 2 Min Duty Cycle) *
Brightness
(100% - Pulse 2 Max Duty Cycle) * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness
CAP1166
DS00001621B-page 59 2015 Microchip Technology Inc.
6.34 LED Breathe Period Register
The LED Breathe Period register determines the overall period of a breathe operation as determined by the LED_CTL
registers (see Table 6-52 - setting 11b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 2976ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
6.35 LED Configuration Register
The LED Configuration register controls general LED behavior as well as the number of pulses that are sent for the
PULSE LED output behavior.
Bit 6 - RAMP_ALERT - Determines whether the device will assert the ALERT# pin when LEDs actuated by the LED
Output Control register bits have finished their respective behaviors. Interrupts will only be generated if the LED activity
is generated by writing the LED Output Control registers. Any LED activity associated with touch detection will not cause
an interrupt to be generated when the LED behavior has been finished.
• ‘0’ (default) - The ALERT# pin will not be asserted when LEDs actuated by the LED Output Control register have
finished their programmed behaviors.
• ‘1’ - The ALERT# pin will be asserted whenever any LED that is actuated by the LED Output Control register has
finished its programmed behavior.
Bits 5 - 3 - PULSE2_CNT[2:0] - Determines the number of pulses used for the Pulse 2 behavior as shown in Table 6-58.
Bits 2 - 0 - PULSE1_CNT[2:0] - Determines the number of pulses used for the Pulse 1 behavior as shown in Table 6-58.
FIGURE 6-4: Pulse 2 Behavior with Inverted Polarity
TABLE 6-56: LED BREATHE PERIOD REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
86h R/W LED Breathe
Period - BR_
PER6
BR_
PER5
BR_
PER4
BR_
PER3
BR_
PER2
BR_
PER1
BR_
PER0 5Dh
TABLE 6-57: LED CONFIGURATION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
88h R/W LED Config - RAMP_
ALERT PULSE2_CNT[2:0] PULSE1_CNT[2:0] 04h
Normal – untouched
operation
Normal – untouched
operation
Touch Detected
Pulse 2 Max Duty Cycle * Brightness
Pulse 2 Min Duty Cycle * Brightness
X additional pulses after release
Release Detected
Pulse
Period
(P2_PER)
LED
Brightness . . .
2015 Microchip Technology Inc. DS00001621B-page 60
CAP1166
6.36 LED Duty Cycle Registers
The LED Duty Cycle registers determine the minimum and maximum duty cycle settings used for the LED for each LED
behavior. These settings affect the brightness of the LED when it is fully off and fully on.
The LED driver duty cycle will ramp up from the minimum duty cycle to the maximum duty cycle and back down again.
APPLICATION NOTE: When operating in Direct behavior mode, changes to the Duty Cycle settings will be applied
immediately. When operating in Breathe, Pulse 1, or Pulse 2 modes, the LED must be
unactuated and then re-actuated before changes to behavior are processed.
Bits 7 - 4 - X_MAX_DUTY[3:0] - Determines the maximum PWM duty cycle for the LED drivers as shown in Table 6-60.
Bits 3 - 0 - X_MIN_DUTY[3:0] - Determines the minimum PWM duty cycle for the LED drivers as shown in Table 6-60.
TABLE 6-58: PULSEX_CNT DECODE
PULSEX_CNT[2:0]
Number of Breaths
21 0
0 0 0 1 (default - Pulse 2)
00 1 2
01 0 3
01 1 4
1 0 0 5 (default - Pulse 1)
10 1 6
11 0 7
11 1 8
TABLE 6-59: LED DUTY CYCLE REGISTERS
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
90h R/W LED Pulse 1 Duty
Cycle P1_MAX_DUTY[3:0] P1_MIN_DUTY[3:0] F0h
91h R/W LED Pulse 2 Duty
Cycle P2_MAX_DUTY[3:0] P2_MIN_DUTY[3:0] F0h
92h R/W LED Breathe
Duty Cycle BR_MAX_DUTY[3:0] BR_MIN_DUTY[3:0] F0h
93h R/W Direct Duty Cycle DR_MAX_DUTY[3:0] DR_MIN_DUTY[3:0] F0h
TABLE 6-60: LED DUTY CYCLE DECODE
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
0 0 0 0 7% 0%
0 0 0 1 9% 7%
0 0 1 0 11% 9%
0 0 1 1 14% 11%
0 1 0 0 17% 14%
0 1 0 1 20% 17%
0 1 1 0 23% 20%
0 1 1 1 26% 23%
1 0 0 0 30% 26%
1 0 0 1 35% 30%
1 0 1 0 40% 35%
CAP1166
DS00001621B-page 61 2015 Microchip Technology Inc.
6.37 LED Direct Ramp Rates Register
The LED Direct Ramp Rates register control the rising and falling edge time of an LED that is configured to operate in
Direct behavior mode. The rising edge time corresponds to the amount of time the LED takes to transition from its minimum
duty cycle to its maximum duty cycle. Conversely, the falling edge time corresponds to the amount of time that
the LED takes to transition from its maximum duty cycle to its minimum duty cycle.
Bits 5 - 3 - RISE_RATE[2:0] - Determines the rising edge time of an LED when it transitions from its minimum drive state
to its maximum drive state as shown in Table 6-62.
Bits 2 - 0 - FALL_RATE[2:0] - Determines the falling edge time of an LED when it transitions from its maximum drive
state to its minimum drive state as shown in Table 6-62.
6.38 LED Off Delay Register
The LED Off Delay register determines the amount of time that an LED remains at its maximum duty cycle (or minimum
as determined by the polarity controls) before it starts to ramp down. If the LED is operating in Breathe mode, this delay
is applied at the top of each “breath”. If the LED is operating in the Direct mode, this delay is applied when the LED is
unactuated.
1 0 1 1 46% 40%
1 1 0 0 53% 46%
1 1 0 1 63% 53%
1 1 1 0 77% 63%
1 1 1 1 100% 77%
TABLE 6-61: LED DIRECT RAMP RATES REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
94h R/W LED Direct Ramp
Rates - - RISE_RATE[2:0] FALL_RATE[2:0] 00h
TABLE 6-62: RISE / FALL RATE DECODE
RISE_RATE/ FALL_RATE/ Bit Decode
Rise / Fall Time (TRISE / TFALL)
21 0
00 0 0
0 0 1 250ms
0 1 0 500ms
0 1 1 750ms
1 0 0 1s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2s
TABLE 6-63: LED OFF DELAY REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
95h R/W LED Off Delay
Register - BR_OFF_DLY[2:0] DIR_OFF_DLY[3:0] 00h
TABLE 6-60: LED DUTY CYCLE DECODE (CONTINUED)
x_MAX/MIN_Duty [3:0]
Maximum Duty Cycle Minimum Duty Cycle
3 21 0
2015 Microchip Technology Inc. DS00001621B-page 62
CAP1166
Bits 6 - 4 - BR_OFF_DLY[2:0] - Determines the Breathe behavior mode off delay, which is the amount of time an LED
in Breathe behavior mode remains inactive after it finishes a breathe pulse (ramp on and ramp off), as shown in Figure 6-
5 (non-inverted polarity LEDx_POL = 1) and Figure 6-6 (inverted polarity LEDx_POL = 0). Available settings are shown
in Table 6-64.
FIGURE 6-5: Breathe Behavior with Non-Inverted Polarity
FIGURE 6-6: Breathe Behavior with Inverted Polarity
LED Actuated
100% - Breathe Max Min Cycle * Brightness
100% - Breathe Min Duty Cycle *
Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
LED Actuated
Breathe Max Duty Cycle * Brightness
Breathe Min Duty Cycle * Brightness
LED Unactuated
Breathe Off
Delay
(BR_OFF_DLY)
LED
Brightness
Breathe
Period
(BR_PER)
CAP1166
DS00001621B-page 63 2015 Microchip Technology Inc.
Bits 3 - 0 - DIR_OFF_DLY[3:0] - Determines the turn-off delay, as shown in Table 6-65, for all LEDs that are configured
to operate in Direct behavior mode.
The Direct behavior operation is determined by the combination of programmed Rise Time, Fall Time, Min and Max Duty
cycles, Off Delay, and polarity. Figure 6-7 shows the behavior for non-inverted polarity (LEDx_POL = 1) while Figure 6-
8 shows the behavior for inverted polarity (LEDx_POL = 0).
TABLE 6-64: BREATHE OFF DELAY SETTINGS
BR_OFF_DLY [2:0]
OFF Delay
2 10
0 0 0 0 (default)
0 0 1 0.25s
0 1 0 0.5s
0 1 1 0.75s
1 0 0 1.0s
1 0 1 1.25s
1 1 0 1.5s
1 1 1 2.0s
FIGURE 6-7: Direct Behavior for Non-Inverted Polarity
FIGURE 6-8: Direct Behavior for Inverted Polarity
Normal –
untouched
operation
RISE_RATE
Setting (tRISE)
(100% - Max Duty
Cycle) * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
(100% - Min Duty Cycle) *
Brightness LED
Brightness
Normal –
untouched
operation RISE_RATE
Setting (tRISE)
Min Duty Cycle * Brightness
Touch
Detected
Release
Detected
Off Delay
(tOFF_DLY)
FALL_RATE
Setting (tFALL)
Normal –
untouched
operation
Max Duty Cycle * Brightness
LED
Brightness
2015 Microchip Technology Inc. DS00001621B-page 64
CAP1166
6.39 Sensor Input Calibration Registers
The Sensor Input Calibration registers hold the 10-bit value that represents the last calibration value.
TABLE 6-65: OFF DELAY DECODE
OFF Delay[3:0] Bit Decode
OFF Delay (tOFF_DLY)
32 1 0
00 0 0 0
0 0 0 1 250ms
0 0 1 0 500ms
0 0 1 1 750ms
0 1 0 0 1s
0 1 0 1 1.25s
0 1 1 0 1.5s
0 1 1 1 2s
1 0 0 0 2.5s
1 0 0 1 3.0s
1 0 1 0 3.5s
1 0 1 1 4.0s
1 1 0 0 4.5s
All others 5.0s
TABLE 6-66: SENSOR INPUT CALIBRATION REGISTERS
ADDR Register R/W B7 B6 B5 B4 B3 B2 B1 B0 Default
B1h Sensor Input 1
Calibration R CAL1_9 CAL1_8 CAL1_7 CAL1_6 CAL1_5 CAL1_4 CAL1_3 CAL1_2 00h
B2h Sensor Input 2
Calibration R CAL2_9 CAL2_8 CAL2_7 CAL2_6 CAL2_5 CAL2_4 CAL2_3 CAL2_2 00h
B3h Sensor Input 3
Calibration R CAL3_9 CAL3_8 CAL3_7 CAL3_6 CAL3_5 CAL3_4 CAL3_3 CAL3_2 00h
B4h Sensor Input 4
Calibration R CAL4_9 CAL4_8 CAL4_7 CAL4_6 CAL4_5 CAL4_4 CAL4_3 CAL4_2 00h
B5h Sensor Input 5
Calibration R CAL5_9 CAL5_8 CAL5_7 CAL5_6 CAL5_5 CAL5_4 CAL5_3 CAL5_2 00h
B6h Sensor Input 6
Calibration R CAL6_9 CAL6_8 CAL6_7 CAL6_6 CAL6_5 CAL6_4 CAL6_3 CAL6_2 00h
B9h
Sensor Input
Calibration LSB
1
R CAL4_1 CAL4_0 CAL3_1 CAL3_0 CAL2_1 CAL2_0 CAL1_1 CAL1_0 00h
BAh
Sensor Input
Calibration LSB
2
R - - - - CAL6_1 CAL6_0 CAL5_1 CAL5_0 00h
CAP1166
DS00001621B-page 65 2015 Microchip Technology Inc.
6.40 Product ID Register
The Product ID register stores a unique 8-bit value that identifies the device.
6.41 Manufacturer ID Register
The Vendor ID register stores an 8-bit value that represents Microchip.
6.42 Revision Register
The Revision register stores an 8-bit value that represents the part revision.
TABLE 6-67: PRODUCT ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FDh R Product ID 0 1 0 1 0 0 0 1 51h
TABLE 6-68: VENDOR ID REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FEh R Manufacturer ID 0 1 0 1 1 1 0 1 5Dh
TABLE 6-69: REVISION REGISTER
ADDR R/W Register B7 B6 B5 B4 B3 B2 B1 B0 Default
FFh R Revision 1 0 0 0 0 0 1 1 83h
2015 Microchip Technology Inc. DS00001621B-page 66
CAP1166
7.0 PACKAGE INFORMATION
7.1 CAP1166 Package Drawings
Note: For the most current package drawings, see the Microchip Packaging Specification at:
http://www.microchip.com/packaging.
FIGURE 7-1: 24-Pin SSOP Package Drawing
CAP1166
DS00001621B-page 67 2015 Microchip Technology Inc.
FIGURE 7-2: 24-Pin SSOP Package Dimensions
2015 Microchip Technology Inc. DS00001621B-page 68
CAP1166
FIGURE 7-3: CAP1166 PCB Land Pattern - 24-Pin SSOP
CAP1166
DS00001621B-page 69 2015 Microchip Technology Inc.
FIGURE 7-4: 20-Pin QFN 4mm x 4mm Package Drawing
2015 Microchip Technology Inc. DS00001621B-page 70
CAP1166
FIGURE 7-5: 20-Pin QFN 4mm x 4mm Package Dimensions
FIGURE 7-6: 20-Pin QFN 4mm x 4mm PCB Drawing
CAP1166
DS00001621B-page 71 2015 Microchip Technology Inc.
7.2 Package Marking
FIGURE 7-7: CAP1166 Package Markings - 20-Pin QFN
FIGURE 7-8: CAP1166 Package Markings - 24-Pin SSOP
C 1 66 - 1
Y WWN N N A
RCC
e3
TOP
BOTTOM
Bottom marking not allowed
PB-FREE/GREEN SYMBOL
(Matte Sn)
Lines 1-3:
Line 4:
Center Horizontal Alignment
Left Horizontal Alignment
PIN 1
0.41
3x 0.56
Line 1 – SMSC Logo without circled R symbol
Line 2 – Device ID, Version
Line 3 – Year, Week, Alphanumeric Traceability Code
Line 4 – Revision, Country Code
1
e3
TOP
BOTTOM
PB-FREE/GREEN SYMBOL
(Matte Sn)
PIN 1
0.6
2x 1.5pt
Line 1 – SMSC Logo with circled R symbol
Line 2 – Device ID, Version
Line 3 – Revision, Year, Week, Traceability Code
Line 2 – Vendor Code, Country Code
PIN 1
C A 11 P 6 6 - 1
Y W NNNA W
®
R
B B 9 3
V V V CC -
Line 1 – Engineering Code
2x 1.5pt
2015 Microchip Technology Inc. DS00001621B-page 72
CAP1166
APPENDIX A: DEVICE DELTA
A.1 Delta from CAP1066 to CAP1166
1. Updated circuitry to improve power supply rejection.
2. Updated LED driver duty cycle decode values to have more distribution at lower values - closer to a logarithmic
curve. See Table 6-60, "LED Duty Cycle Decode".
3. Updated bug that breathe periods were not correct above 2.6s. This includes rise / fall time decodes above 1.5s.
4. Added filtering on RESET pin to prevent errant resets.
5. Updated controls so that the RESET pin assertion places the device into the lowest power state available and
causes an interrupt when released. See Section 5.2, "RESET Pin".
6. Added 1 bit to the LED Off Delay register (see Section 6.38, "LED Off Delay Register") to extend times from 2s
to 5s in 0.5s intervals.
7. Breathe behavior modified. A breathe off delay control was added to the LED Off Delay Register (see Section
6.38, "LED Off Delay Register") so the LEDs can be configured to remain inactive between breathes.
8. Added controls for the LED transition effects when linking LEDs to capacitive sensor inputs. See Section 6.29,
"Linked LED Transition Control Register".
9. Added controls to “mirror” the LED duty cycle outputs so that when polarity changes, the LED brightness levels
look right. These bits are automatically set when polarity is set. Added control to break this auto-set behavior.
See Section 6.30, "LED Mirror Control Register".
10. Added Multiple Touch Pattern detection circuitry. See Section 6.15, "Multiple Touch Pattern Configuration Register".
11. Added General Status register to flag Multiple touches, Multiple Touch Pattern issues and general touch detections.
See Section 6.2, "Status Registers".
12. Added bits 6 and 5 to the Recalibration Configuration register (2Fh - see Section 6.17, "Recalibration Configuration
Register"). These bits control whether the accumulation of intermediate data and the consecutive negative
delta counts counter are cleared when the noise status bit is set.
13. Added Configuration 2 register for LED linking controls, noise detection controls, and control to interrupt on press
but not on release. Added control to change alert pin polarity. See Section 6.6, "Configuration Registers".
14. Updated Deep Sleep behavior so that device does not clear DSLEEP bit on received communications but will
wake to communicate.
15. Changed PWM frequency for LED drivers. The PWM frequency was derived from the programmed breathe
period and duty cycle settings and it ranged from ~4Hz to ~8000 Hz. The PWM frequency has been updated to
be a fixed value of ~2000Hz.
16. Register delta:
Table A.1 Register Delta From CAP1066 to CAP1166
Address Register Delta Delta Default
00h
Page 33
Changed - Main Status /
Control
added bits 7-6 to control gain 00h
02h
Page 34
New - General Status new register to store MTP, MULT, LED,
RESET, and general TOUCH bits
00h
44h
Page 37
New - Configuration 2 new register to control alert polarity, LED
touch linking behavior, LED output behavior,
and noise detection, and interrupt on
release
40h
24h
Page 41
Changed - Averaging
Control
updated register bits - moved
SAMP_AVG[2:0] bits and added SAMP_-
TIME bit 1. Default changed
39h
2Bh
Page 44
New - Multiple Touch
Pattern Configuration
new register for Multiple Touch Pattern
configuration - enable and threshold settings
80h
CAP1166
DS00001621B-page 73 2015 Microchip Technology Inc.
2Dh
Page 45
New - Multiple Touch
Pattern Register
new register for Multiple Touch Pattern
detection circuitry - pattern or number of
sensor inputs
3Fh
2Fh
Page 45
Changed - Recalibration
Configuration
updated register - updated CAL_CFG bit
decode to add a 128 averages setting and
removed highest time setting. Default
changed. Added bit 6 NO_CLR_INTD and
bit 5 NO_CLR_NEG.
8Ah
38h
Page 47
Changed - Sensor Input
Noise Threshold
updated register bits - removed bits 7 - 3
and consolidated all controls into bits 1 - 0.
These bits will set the noise threshold for
all channels. Default changed
01h
39h Removed - Noise
Threshold Register 2
removed register n/a
41h
Page 48
Changed - Standby Configuration
updated register bits - moved
STBY_AVG[2:0] bits and added STBY_-
TIME bit 1. Default changed
39h
77h
Page 53
New - Linked LED Transition
Control
new register to control transition effect
when LED linked to sensor inputs
00h
79h
Page 54
New - LED Mirror Control new register to control LED output mirroring
for brightness control when polarity
changed
00h
90h
Page 60
Changed - LED Pulse 1
Duty Cycle
changed bit decode to be more logarithmic F0h
91h
Page 60
Changed - LED Pulse 2
Duty Cycle
changed bit decode to be more logarithmic F0h
92h
Page 60
Changed - LED Breathe
Duty Cycle
changed bit decode to be more logarithmic F0h
93h
Page 60
Changed - LED Direct
Duty Cycle
changed bit decode to be more logarithmic F0h
95h Added controls - LED Off
Delay
Added bits 6-4 BR_OFF_DLY[2:0]
Added bit 3 DIR_OFF_DLY[3]
00h
FDh
Page 65
Changed - Product ID Changed bit decode for CAP1166 51h
Table A.1 Register Delta From CAP1066 to CAP1166 (continued)
Address Register Delta Delta Default
2015 Microchip Technology Inc. DS00001621B-page 74
CAP1166
APPENDIX B: DATA SHEET REVISION HISTORY
Revision Section/Figure/Entry Correction
DS00001621B (02-09-15)
Features, Table 2-1, Table 2-
2, "Pin Types", Section 5.0,
"General Description"
References to BC-Link Interface, BC_DATA, BC_-
CLK, BC-IRQ#, BC-Link bus have been removed
Application Note under Table
2-6
[BC-Link] hidden in data sheet
Table 3-2, "Electrical Specifications"
BC-Link Timing Section hidden in data sheet
Table 4-1 Protocol Used for 68K Pull Down Resistor changed
from “BC-Link Communications” to “Reserved”
Section 4.2.2, "SMBus
Address and RD / WR Bit"
Replaced “client address” with “slave address” in this
section.
Section 4.2.4, SMBus ACK
and NACK Bits, Section 4.2.5,
SMBus Stop Bit,Section 4.2.7,
SMBus and I2C Compatibility
Replaced “client” with “slave” in these sections.
Table 4-4, "Read Byte Protocol"
Heading changed from “Client Address” to “Slave
Address”
Table 6-1 Register Name for Register Address 77h changed
from “LED Linked Transition Control” to “Linked LED
Transition Control”
Section 6.30 changed CS6 to LED6
Table 6-53 Modified B3 bit name
Section 7.7 Package Marking Updated package drawing
Appendix A: Device Delta changed 2Dh to 2Fh in item #12
Product Identification System Removed BC-Link references
REV A REV A replaces previous SMSC version Rev. 1.32 (01-05-12)
Rev. 1.32 (01-05-12) Table 3-2, "Electrical Specifications"
Added conditions for tHD:DAT.
Section 4.2.7, "SMBus and
I2C Compatibility"
Renamed from “SMBus and I2C Compliance.”
First paragraph, added last sentence: “For information
on using the CAP1188 in an I2C system, refer to
SMSC AN 14.0 SMSC Dedicated Slave Devices in
I
2C Systems.”
Added: CAP1188 supports I2C fast mode at 400kHz.
This covers the SMBus max time of 100kHz.
Section 6.4, "Sensor Input
Delta Count Registers"
Changed negative value cap from FFh to 80h.
Rev. 1.31 (08-18-11) Section 4.3.3, "SMBus Send
Byte"
Added an application note: The Send Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit is
set).
Section 4.3.4, "SMBus
Receive Byte"
Added an application note: The Receive Byte protocol
is not functional in Deep Sleep (i.e., DSLEEP bit
is set).
Rev. 1.3 (05-18-11) Section 6.42, "Revision Register"
Updated revision ID from 82h to 83h.
Rev. 1.2 (02-10-11) Section A.8, "Delta from Rev
B (Mask B0) to Rev C (Mask
B1)"
Added.
CAP1166
DS00001621B-page 75 2015 Microchip Technology Inc.
Table 2-1, "Pin Description for
CAP1166"
Changed value in “Unused Connection” column for
the ADDR_COMM pin from “Connect to Ground” to
“n/a“.
Table 3-2, "Electrical Specifications"
PSR improvements made in functional revision B.
Changed PSR spec from ±100 typ and ±200 max
counts / V to ±3 and ±10 counts / V. Conditions
updated.
Section 5.5.2, "Recalibrating
Sensor Inputs"
Added more detail with subheadings for each type of
recalibration.
Section 6.6, "Configuration
Registers"
Added bit 5 BLK_PWR_CTRL to the Configuration 2
Register 44h.
The TIMEOUT bit is set to ‘1’ by default for functional
revision B and is set to ‘0’ by default for functional
revision C.
Section 6.42, "Revision Register"
Updated revision ID in register FFh from 81h to 82h.
Rev. 1.1 (11-17-10) Document Updated for functional revision B. See Section A.7,
"Delta from Rev A (Mask A0) to Rev B (Mask B0)".
Cover Added to General Description: “includes circuitry and
support for enhanced sensor proximity detection.”
Added the following Features:
Calibrates for Parasitic Capacitance
Analog Filtering for System Noise Sources
Press and Hold feature for Volume-like Applications
Table 3-2, "Electrical Specifications"
Conditions for Power Supply Rejection modified adding
the following:
Sampling time = 2.56ms
Averaging = 1
Negative Delta Counts = Disabled
All other parameters default
Section 6.11, "Calibration Activate
Register"
Updated register description to indicate which re-calibration
routine is used.
Section 6.14, "Multiple Touch
Configuration Register"
Updated register description to indicate what will
happen.
Table 6-34, "CSx_BN_TH Bit
Decode"
Table heading changed from “Threshold Divide Setting”
to “Percent Threshold Setting”.
Section 7.0, "Package Information"
Added PCB land pattern.
CAP1166-1 added in an SSOP package.
Rev. 1.0 (06-14-10) Initial release
Revision Section/Figure/Entry Correction
2015 Microchip Technology Inc. DS00001621B-page 76
CAP1166
THE MICROCHIP WEB SITE
Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains
the following information:
• Product Support – Data sheets and errata, application notes and sample programs, design resources, user’s
guides and hardware support documents, latest software releases and archived software
• General Technical Support – Frequently Asked Questions (FAQ), technical support requests, online discussion
groups, Microchip consultant program member listing
• Business of Microchip – Product selector and ordering guides, latest Microchip press releases, listing of seminars
and events, listings of Microchip sales offices, distributors and factory representatives
CUSTOMER CHANGE NOTIFICATION SERVICE
Microchip’s customer notification service helps keep customers current on Microchip products. Subscribers will receive
e-mail notification whenever there are changes, updates, revisions or errata related to a specified product family or
development tool of interest.
To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification”
and follow the registration instructions.
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
• Distributor or Representative
• Local Sales Office
• Field Application Engineer (FAE)
• Technical Support
Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://www.microchip.com/support
2015 Microchip Technology Inc. DS00001621B-page 77
CAP1166
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. [X] - 1 - XXX - [X](1)
l l l l
Device Temperature Package Tape and Reel
Range Option
Examples:
Note 1: Tape and Reel identifier only appears in the catalog part number description. This identifier is used for ordering
purposes and is not printed on the device package. Check with your Microchip Sales Office for package availability
with the Tape and Reel option.
Device: CAP1166
Temperature
Range:
Blank = 0°C to +85°C (Extended Commercial)
Package: BP = QFN
CZC = SSOP
Tape and
Reel Option:
TR = Tape and Reel(1)
CAP1166-1-BP-TR
20-pin QFN 4mm x 4mm (RoHS compliant)
Six capacitive touch sensor inputs, Six LED
drivers, Dedicated Wake, Reset, SMBus /
BC-Link / SPI interfaces
Reel size is 4,000 pieces
CAP1166-1-CZC-TR
24-pin SSOP (RoHS compliant)
Six capacitive touch sensor inputs, Six LED
drivers, Dedicated Wake, Reset, SMBus /
BC-Link / SPI interfaces
Reel size is 2,500 pieces
2015 Microchip Technology Inc. DS00001621B-page 78
CAP1166
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device applications and the like is provided only for your convenience and may be
superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO
REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE,
MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of
Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly
or otherwise, under any Microchip intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC, FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer, LANCheck,
MediaLB, MOST, MOST logo, MPLAB, OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC, SST, SST Logo, SuperFlash and
UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are registered trademarks of Microchip Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo, CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit Serial
Programming, ICSP, Inter-Chip Connectivity, KleerNet, KleerNet logo, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK,
MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net, PICkit, PICtail, RightTouch logo, REAL ICE, SQI, Serial
Quad I/O, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.
Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.
GestIC is a registered trademarks of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in
other countries.
All other trademarks mentioned herein are property of their respective companies.
© 2015, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
ISBN: 9781632770318
Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
2015 Microchip Technology Inc. DS00001621B-page 79
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Worldwide Sales and Service
01/27/15