nRF9160
Product Specification
v1.0
4418_1315 v1.0 / 2019-05-29
nRF9160 features
Features:
Microcontroller:
•
®
LTE modem:
®
ARM Cortex -M33
•
Transceiver and baseband
•
243 EEMBC CoreMark score running from flash memory
•
3GPP LTE release 13 Cat-M1 and Cat-NB1 compliant
•
Data watchpoint and trace (DWT), embedded trace macrocell (ETM), and
•
3GPP release 13 coverage enhancement
instrumentation trace macrocell (ITM)
•
3GPP LTE release 14 Cat-NB2 compliant
•
Serial wire debug (SWD)
•
GPS receiver
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Trace port
•
•
1 MB flash
•
256 kB low leakage RAM
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ARM Trustzone
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ARM Cryptocell 310
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Up to 4x SPI master/slave with EasyDMA
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Up to 4x I2C compatible two-wire master/slave with EasyDMA
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Up to 4x UART (CTS/RTS) with EasyDMA
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I2S with EasyDMA
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Digital microphone interface (PDM) with EasyDMA
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4x pulse width modulator (PWM) unit with EasyDMA
•
12-bit, 200 ksps ADC with EasyDMA - eigth configurable channels with
®
•
®
®
3x 32-bit timer with counter mode
•
2x real-time counter (RTC)
•
Programmable peripheral interconnect (PPI)
•
32 general purpose I/O pins
•
Single supply voltage: 3.0 – 5.5 V
•
All necessary clock sources integrated
•
Package: 10 × 16 x 1.04 mm LGA
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Up to 23 dBm output power
•
-108 dBm sensitivity (LTE-M) for low band, -107 dBm for mid
band
•
•
Single 50 Ω antenna interface
LTE band support in hardware:
•
Cat-M1: B1, B2, B3, B4, B5, B8, B12, B13, B14, B17, B18, B19,
B20, B25, B26, B28, B66
•
Cat-NB1/NB2: B1, B2, B3, B4, B5, B8, B12, B13, B17, B18, B20,
B25, B26, B28, B66
•
programmable gain
•
GPS L1 C/A supported
RF transceiver for global coverage
Supports SIM and eSIM with an ETSI TS 102 221 compatible UICC
interface
•
Power saving features: DRX, eDRX, PSM
•
IP v4/v6 stack
•
Secure socket (TLS/DTLS) API
Current consumption @ 3.7 V:
•
•
Power saving mode (PSM) floor current: 4 µA
•
Application core idle: 1.8 µA
•
Modem: 2.2 µA
eDRX @ 82.91s: 19 µA
Applications:
•
Sensor networks
•
Industrial
•
Logistics and asset tracking
•
Retail and monitor devices
•
Smart energy
•
Medical devices
•
Smart building automation
•
Wearables
•
Smart agriculture
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Contents
nRF9160 features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
1
Revision history.
2
About this document.
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4
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2.1 Document status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Peripheral chapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Register tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.1 Fields and values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Permissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4.1 DUMMY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Product overview.
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Peripheral interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.1 Peripheral ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.2 Peripherals with shared ID . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.3 Peripheral registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.4 Bit set and clear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.5 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.6 Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.7 Publish / Subscribe . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.8 Shortcuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.9 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.10 Secure/non-secure peripherals . . . . . . . . . . . . . . . . . . . . . . . .
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Application core.
19
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4.1 CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1.1 CPU and support module configuration . . . . . . . . . . . . . . . . . . . . .
4.1.2 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.1 Memory map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.2 Instantiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.3 Peripheral access control capabilities . . . . . . . . . . . . . . . . . . . . . .
4.3 VMC — Volatile memory controller . . . . . . . . . . . . . . . . . . . . . . . .
4.3.1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 NVMC — Non-volatile memory controller . . . . . . . . . . . . . . . . . . . . . .
4.4.1 Writing to flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.2 Erasing a secure page in flash . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.3 Erasing a non-secure page in flash . . . . . . . . . . . . . . . . . . . . . . .
4.4.4 Writing to user information configuration registers (UICR) . . . . . . . . . . . . .
4.4.5 Erase all . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.6 NVMC protection mechanisms . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.7 Cache . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.8 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.9 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 FICR — Factory information configuration registers . . . . . . . . . . . . . . . . . .
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4.5.1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6 UICR — User information configuration registers . . . . . . . . . . . . . . . . . . .
4.6.1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.1 EasyDMA error handling . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.2 EasyDMA array list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8 AHB multilayer interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Power and clock management.
48
. . . . . . . . . . . . . . . . . . . . . . .
5.1 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.1 Power management . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.2 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.3 Power supply monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.4 Clock management . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1.5 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 Current consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Register description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.1 POWER — Power control . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.2 CLOCK — Clock control . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.3 REGULATORS — Voltage regulators control . . . . . . . . . . . . . . . . . . . .
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Peripherals.
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1 CRYPTOCELL — ARM TrustZone CryptoCell 310 . . . . . . . . . . . . . . . . . . . . 75
6.1.1 Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
6.1.2 Always-on (AO) power domain . . . . . . . . . . . . . . . . . . . . . . . . . 76
6.1.3 Lifecycle state (LCS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
6.1.4 Cryptographic key selection . . . . . . . . . . . . . . . . . . . . . . . . . . 77
6.1.5 Direct memory access (DMA) . . . . . . . . . . . . . . . . . . . . . . . . . 77
6.1.6 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
77
6.1.7 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
6.1.8 Host interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
6.2 DPPI - Distributed programmable peripheral interconnect . . . . . . . . . . . . . . . 82
6.2.1 Subscribing to and publishing on channels . . . . . . . . . . . . . . . . . . . . 83
6.2.2 DPPI configuration (DPPIC) . . . . . . . . . . . . . . . . . . . . . . . . . . 85
6.2.3 Connection examples . . . . . . . . . . . . . . . . . . . . . . . . . . . .
85
6.2.4 Special considerations for a system implementing TrustZone for Cortex-M processors . . . 86
6.2.5 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.3 EGU — Event generator unit . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.3.1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.3.2 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
6.4 GPIO — General purpose input/output . . . . . . . . . . . . . . . . . . . . . . . 95
6.4.1 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
6.4.2 Pin sense mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . .
97
6.4.3 GPIO security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
6.4.4 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
6.4.5 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
6.5 GPIOTE — GPIO tasks and events . . . . . . . . . . . . . . . . . . . . . . . . . 105
6.5.1 Pin events and tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
6.5.2 Port event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
6.5.3 Tasks and events pin configuration . . . . . . . . . . . . . . . . . . . . . .
106
6.5.4 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
6.5.5 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
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6.6 IPC — Interprocessor communication . . . . . . . . . . . . . . . . . . . . . . .
6.6.1 IPC and PPI connections . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6.2 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6.3 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7 I2S — Inter-IC sound interface . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.2 Transmitting and receiving . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.3 Left right clock (LRCK) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.4 Serial clock (SCK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.5 Master clock (MCK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.6 Width, alignment and format . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.7 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.8 Module operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.9 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.10 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7.11 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8 KMU — Key management unit . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8.1 Functional view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8.2 Access control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8.3 Protecting the UICR content . . . . . . . . . . . . . . . . . . . . . . . . .
6.8.4 Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8.5 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9 PDM — Pulse density modulation interface . . . . . . . . . . . . . . . . . . . . .
6.9.1 Master clock generator . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.2 Module operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.3 Decimation filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.4 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.5 Hardware example . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.6 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.7 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9.8 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.10 PWM — Pulse width modulation . . . . . . . . . . . . . . . . . . . . . . . .
6.10.1 Wave counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.10.2 Decoder with EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.10.3 Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.10.4 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.10.5 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11 RTC — Real-time counter . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.1 Clock source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.2 Resolution versus overflow and the prescaler . . . . . . . . . . . . . . . . .
6.11.3 Counter register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.4 Overflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.5 Tick event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.6 Event control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.7 Compare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.8 Task and event jitter/delay . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.9 Reading the counter register . . . . . . . . . . . . . . . . . . . . . . . .
6.11.10 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.11.11 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12 SAADC — Successive approximation analog-to-digital converter . . . . . . . . . . . .
6.12.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.2 Digital output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.3 Analog inputs and channels . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.4 Operation modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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6.12.5 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.6 Resistor ladder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.7 Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.8 Acquisition time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.9 Limits event monitoring . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.10 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.11 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.12.12 Performance factors . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.13 SPIM — Serial peripheral interface master with EasyDMA . . . . . . . . . . . . . .
6.13.1 SPI master transaction sequence . . . . . . . . . . . . . . . . . . . . . . .
6.13.2 Master mode pin configuration . . . . . . . . . . . . . . . . . . . . . . .
6.13.3 Shared resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.13.4 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.13.5 Low power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.13.6 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.13.7 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14 SPIS — Serial peripheral interface slave with EasyDMA . . . . . . . . . . . . . . . .
6.14.1 Shared resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.2 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.3 SPI slave operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.4 Semaphore operation . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.5 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.6 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.14.7 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15 SPU - System protection unit . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.1 General concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.2 Flash access control . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.3 RAM access control . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.4 Peripheral access control . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.5 Pin access control . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.6 DPPI access control . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.15.7 External domain access control . . . . . . . . . . . . . . . . . . . . . . .
6.15.8 TrustZone for Cortex-M ID allocation . . . . . . . . . . . . . . . . . . . . .
6.15.9 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16 TIMER — Timer/counter . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.1 Capture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.2 Compare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.3 Task delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.4 Task priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.5 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.16.6 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17 TWIM — I2C compatible two-wire interface master with EasyDMA . . . . . . . . . . .
6.17.1 Shared resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.2 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.3 Master write sequence . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.4 Master read sequence . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.5 Master repeated start sequence . . . . . . . . . . . . . . . . . . . . . . .
6.17.6 Low power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.7 Master mode pin configuration . . . . . . . . . . . . . . . . . . . . . . .
6.17.8 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.9 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.17.10 Pullup resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.18 TWIS — I2C compatible two-wire interface slave with EasyDMA . . . . . . . . . . . .
6.18.1 Shared resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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6.18.2 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.18.3 TWI slave responding to a read command . . . . . . . . . . . . . . . . . . .
6.18.4 TWI slave responding to a write command . . . . . . . . . . . . . . . . . . .
6.18.5 Master repeated start sequence . . . . . . . . . . . . . . . . . . . . . . .
6.18.6 Terminating an ongoing TWI transaction . . . . . . . . . . . . . . . . . . . .
6.18.7 Low power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.18.8 Slave mode pin configuration . . . . . . . . . . . . . . . . . . . . . . . .
6.18.9 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.18.10 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19 UARTE — Universal asynchronous receiver/transmitter with EasyDMA . . . . . . . . .
6.19.1 EasyDMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.2 Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.3 Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.4 Error conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.5 Using the UARTE without flow control . . . . . . . . . . . . . . . . . . . .
6.19.6 Parity and stop bit configuration . . . . . . . . . . . . . . . . . . . . . . .
6.19.7 Low power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.8 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.9 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.19.10 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.20 WDT — Watchdog timer . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.20.1 Reload criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.20.2 Temporarily pausing the watchdog . . . . . . . . . . . . . . . . . . . . . .
6.20.3 Watchdog reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.20.4 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.20.5 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . .
7
LTE modem.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.2 SIM card interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3 LTE modem coexistence interface . . . . . . . . . . . . . . . . . . . . . . . . .
7.4 LTE modem RF control external interface . . . . . . . . . . . . . . . . . . . . . .
7.5 RF front-end interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.6 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.6.1 Key RF parameters for Cat-M1 . . . . . . . . . . . . . . . . . . . . . . . .
7.6.2 Key RF parameters for Cat-NB1 and Cat-NB2 . . . . . . . . . . . . . . . . . .
7.6.3 Receiver parameters for Cat-M1 . . . . . . . . . . . . . . . . . . . . . . .
7.6.4 Receiver parameters for Cat-NB1 and Cat-NB2 . . . . . . . . . . . . . . . . . .
7.6.5 Transmitter parameters for Cat-M1 . . . . . . . . . . . . . . . . . . . . . .
7.6.6 Transmitter parameters for Cat-NB1 and Cat-NB2 . . . . . . . . . . . . . . . .
8
GPS receiver.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.1 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9
Debug and trace.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1 Special consideration regarding debugger access . . . . . . . . . . . . . . . . .
9.1.2 DAP - Debug access port . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3 Debug interface mode . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.4 Real-time debug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.5 Trace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.6 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.7 Electrical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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9.2 CTRL-AP - Control access port . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1 Reset request . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2 Erase all . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3 Mailbox interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.4 Disabling erase protection . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.5 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.6 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3 TAD - Trace and debug control . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3.1 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10 Hardware and layout.
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.1 Pin assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.1.1 Pin assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2 Mechanical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2.1 16.00 x 10.50 mm package . . . . . . . . . . . . . . . . . . . . . . . . .
11 Recommended operating conditions.
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389
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11.1 VDD_GPIO considerations . . . . . . . . . . . . . . . . . . . . . . . . . . .
390
12 Absolute maximum ratings.
13 Ordering information.
13.1
13.2
13.3
13.4
13.5
. . . . . . . . . . . . . . . . . . . . . . . .
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IC marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Box labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Order code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code ranges and values . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Product options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14 Regulatory information.
15 Legal notices.
. . . . . . . . . . . . . . . . . . . . . . . . . .
397
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
398
15.1 Liability disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15.2 Life support applications . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15.3 RoHS and REACH statement . . . . . . . . . . . . . . . . . . . . . . . . . .
15.4 Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15.5 Copyright notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1
Revision history
Date
Version
Description
May 2019
1.0
First release
4418_1315 v1.0
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2
About this document
This document is organized into chapters that are based on the modules and peripherals available in the
IC.
2.1 Document status
The document status reflects the level of maturity of the document.
Document name
Description
Objective Product Specification (OPS)
Applies to document versions up to 1.0.
This document contains target specifications for
product development.
Product Specification (PS)
Applies to document versions 1.0 and higher.
This document contains final product
specifications. Nordic Semiconductor ASA reserves
the right to make changes at any time without
notice in order to improve design and supply the
best possible product.
Table 1: Defined document names
2.2 Peripheral chapters
Every peripheral has a unique capitalized name or an abbreviation of its name, e.g. TIMER, used for
identification and reference. This name is used in chapter headings and references, and it will appear in
the ARM® Cortex® Microcontroller Software Interface Standard (CMSIS) hardware abstraction layer to
identify the peripheral.
The peripheral instance name, which is different from the peripheral name, is constructed using the
peripheral name followed by a numbered postfix, starting with 0, for example, TIMER0. A postfix is
normally only used if a peripheral can be instantiated more than once. The peripheral instance name is
also used in the CMSIS to identify the peripheral instance.
The chapters describing peripherals may include the following information:
• A detailed functional description of the peripheral
• Register configuration for the peripheral
• Electrical specification tables, containing performance data which apply for the operating conditions
described in Peripheral chapters on page 10.
2.3 Register tables
Individual registers are described using register tables. These tables are built up of two sections. The first
three colored rows describe the position and size of the different fields in the register. The following rows
describe the fields in more detail.
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2.3.1 Fields and values
The Id (Field Id) row specifies the bits that belong to the different fields in the register. If a field has
enumerated values, then every value will be identified with a unique value id in the Value Id column.
A blank space means that the field is reserved and read as undefined, and it also must be written as 0
to secure forward compatibility. If a register is divided into more than one field, a unique field name is
specified for each field in the Field column. The Value Id may be omitted in the single-bit bit fields when
values can be substituted with a Boolean type enumerator range, e.g. true/false, disable(d)/enable(d), on/
off, and so on.
Values are usually provided as decimal or hexadecimal. Hexadecimal values have a 0x prefix, decimal
values have no prefix.
The Value column can be populated in the following ways:
• Individual enumerated values, for example 1, 3, 9.
• Range of values, e.g. [0..4], indicating all values from and including 0 and 4.
• Implicit values. If no values are indicated in the Value column, all bit combinations are supported, or
alternatively the field's translation and limitations are described in the text instead.
If two or more fields are closely related, the Value Id, Value, and Description may be omitted for all but
the first field. Subsequent fields will indicate inheritance with '..'.
A feature marked Deprecated should not be used for new designs.
2.3.2 Permissions
Different fields in a register might have different access permissions enforced by hardware.
The access permission for each register field is documented in the Access column in the following ways:
Access
Description
Hardware behavior
RO
Read-only
Field can only be read. A write will be ignored.
WO
Write-only
Field can only be written. A read will return an undefined value.
RW
Read-write
Field can be read and written multiple times.
W1
Write-once
Field can only be written once per reset. Any subsequent write will be ignored. A read will return an undefined value.
RW1
Read-write-once
Field can be read multiple times, but only written once per reset. Any subsequent write will be ignored.
Table 2: Register field permission schemes
2.4 Registers
Register
Offset
DUMMY
0x514
Security
Description
Example of a register controlling a dummy feature
Table 3: Register overview
2.4.1 DUMMY
Address offset: 0x514
Example of a register controlling a dummy feature
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About this document
Bit number
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 6 5 4 3 2 1 0
ID
D D D D
Reset 0x00050002
ID
Access
Field
A
RW FIELD_A
C C C
B
A A
0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Value ID
Value
Description
Example of a read-write field with several enumerated
values
Disabled
0
The example feature is disabled
NormalMode
1
The example feature is enabled in normal mode
ExtendedMode
2
The example feature is enabled along with extra
functionality
B
RW FIELD_B
C
RW FIELD_C
D
RW FIELD_D
Example of a deprecated read-write field
Disabled
0
The override feature is disabled
Enabled
1
The override feature is enabled
Example of a read-write field with a valid range of values
ValidRange
[2..7]
Example of allowed values for this field
Example of a read-write field with no restriction on the
values
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Deprecated
3
Product overview
3.1 Introduction
The nRF9160 is a low-power cellular IoT (internet of things) solution, integrating an ARM® Cortex®-M33
processor with advanced security features, a range of peripherals, as well as a complete LTE modem
compliant with 3GPP LTE release 13 Cat-M1 and Cat-NB1, and 3GPP LTE release 14 Cat-NB1 and Cat-NB2
standards.
The ARM® Cortex-M33 processor is exclusively for user application software, and it offers 1 MB of flash
and 256 kB of RAM dedicated to this use. The M33 application processor shares the power, clock and
peripheral architecture with Nordic Semiconductor nRF51 and nRF52 Series of PAN/LAN SoCs, ensuring
minimal porting efforts.
The peripheral set offers a variety of analog and digital functionality enabling single-chip implementation
of a wide range of cellular IoT (internet of things) applications. ARM® TrustZone® technology, Cryptocell
310 and supporting blocks for system protection and key management, are embedded to enable advanced
security needed for IoT applications.
The LTE modem integrates a very flexible transceiver that in hardware supports frequency range from
700 to 2200 MHz (through a single 50 Ω antenna pin), and a baseband processor handling LTE Cat-M1/
NB1/NB2 protocol layers L1-L3 as well as IP upper layers offering secure socket API for the application. The
modem is supported by pre-qualified software builds available for free from Nordic Semiconductor.
On specific nRF9160 device variants, the LTE modem supports A-GPS operation during sleep intervals in
the LTE operation (RRC idle and PSM modes).
3.2 Block diagram
This block diagram illustrates the overall system. Arrows with white heads indicate signals that share
physical pins with other signals.
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Product overview
ETM trace ITM trace
nRF9160
Debug
ETM
AHB-AP
CPU
RAM2
RAM3
slave
slave
RAM1
slave
RAM0
slave
RAM3
slave
RAM2
slave
slave
SysTick
master
NVIC
RAM1
slave
RAM0
ARM
CORTEX-M33
AHB multilayer
SCL
AHB TO APB
BRIDGE
CODE
FICR
UICR
LTE-M modem
master
DPPI
KMU
SPU
master
ARM TrustZone
CryptoCell 310
TWIS [0..3]
EasyDMA
ANT - LTE
/
ANT - GPS
NVMC
UARTE [0..3]
EasyDMA
SDA
master
RTS
CTS
TXD
RXD
EasyDMA
slave
SAADC
slave
AIN0 – AIN7
AREF0 – AREF1
slave
slave
GPIO
slave
P0
(P0.0 – P0.31)
USIM
/
GPS
DMA
master
master
1.8 V USIM
APB
GPIOTE
TWIM [0..3]
EasyDMA
SCK
MOSI
MISO
CSN
MISO
MOSI
SCK
master
TIMER [0..2]
IPC
SPIM [0..3]
EasyDMA
PWM[0..3]
master
WDT
POWER
master
CLOCK
PDM
EasyDMA
master
Clock control
MCK
LRCK
SCL
SDOUT
SDIN
OUT0-OUT3
EasyDMA
master
SPIS [0..3]
EasyDMA
CLK
DIN
RTC [0..1]
APB
SCL
SDA
High frequency
clock sources
High frequency
clock sources
I2S
REGULATORS
EasyDMA
master
Figure 1: Block diagram
3.3 Peripheral interface
Peripherals are controlled by the CPU through configuration registers, as well as task and event registers.
Task registers are inputs, enabling the CPU and other peripherals to initiate a functionality. Event registers
are outputs, enabling a peripheral to trigger tasks in other peripherals and/or the CPU by tying events to
CPU interrupts.
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Product overview
Channel inputs from DPPI
Peripheral
EN
SUBSCRIBE n
TASK n
CHIDX
write
k
OR
SHORTS
task
Peripheral
core
event
INTEN
m
EVENT m
IRQ signal to NVIC
EN
PUBLISH m
CHIDX
Channel outputs to DPPI
Figure 2: Tasks, events, shortcuts, publish, subscribe and interrupts
The distributed programmable peripheral interconnect (DPPI) feature enables peripherals to connect
events to tasks without CPU intervention.
Note: For more information on DPPI and the DPPI channels, see DPPI - Distributed programmable
peripheral interconnect on page 82.
3.3.1 Peripheral ID
Every peripheral is assigned a fixed block of 0x1000 bytes of address space, which is equal to 1024 x 32 bit
registers.
See Instantiation on page 23 for more information about which peripherals are available and where
they are located in the address map.
There is a direct relationship between peripheral ID and base address. For example, a peripheral with base
address 0x40000000 is assigned ID=0, a peripheral with base address 0x40001000 is assigned ID=1, and a
peripheral with base address 0x4001F000 is assigned ID=31.
Peripherals may share the same ID, which may impose one or more of the following limitations:
• Some peripherals share some registers or other common resources.
• Operation is mutually exclusive. Only one of the peripherals can be used at a time.
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Product overview
• Switching from one peripheral to another must follow a specific pattern (disable the first, then enable
the second peripheral).
3.3.2 Peripherals with shared ID
In general (with the exception of ID 0), peripherals sharing an ID and base address may not be used
simultaneously. The user can only enable one peripheral at the time on this specific ID.
When switching between two peripherals sharing an ID, the user should do the following to prevent
unwanted behavior:
•
•
•
•
Disable the previously used peripheral.
Disable any publish/subscribe connection to the DPPI system for the peripheral that is being disabled.
Clear all bits in the INTEN register, i.e. INTENCLR = 0xFFFFFFFF.
Explicitly configure the peripheral that you are about to enable, and do not rely on configuration values
that may be inherited from the peripheral that was disabled.
• Enable the now configured peripheral.
See which peripherals are sharing ID in Instantiation on page 23.
3.3.3 Peripheral registers
Most peripherals feature an ENABLE register. Unless otherwise is specified in the chapter, the peripheral
registers must be configured before enabling the peripheral.
PSEL registers need to be set before a peripheral is enabled or started. Updating PSEL registers while the
peripheral is running has no effect. In order to connect a peripheral to a different GPIO, the peripheral
must be disabled, the PSEL register updated and the peripheral re-enabled. It takes four CPU cycles
between the PSEL register update and the connection between a peripheral and a GPIO becoming
effective.
Note that the peripheral must be enabled before tasks and events can be used.
Most of the register values are lost during System OFF or when a reset is triggered. Some registers will
retain their values in System OFF or for some specific reset sources. These registers are marked as retained
in the register description for a given peripheral. For more info on these retained registers' behavior, see
chapter Reset on page 54.
3.3.4 Bit set and clear
Registers with multiple single-bit bit fields may implement the set-and-clear pattern. This pattern enables
firmware to set and clear individual bits in a register without having to perform a read-modify-write
operation on the main register.
This pattern is implemented using three consecutive addresses in the register map, where the main
register is followed by dedicated SET and CLR registers (in that exact order).
The SET register is used to set individual bits in the main register, while the CLR register is used to clear
individual bits in the main register. Writing 1 to a bit in SET or CLR register will set or clear the same bit in
the main register respectively. Writing 0 to a bit in SET or CLR register has no effect. Reading the SET or
CLR register returns the value of the main register.
Note: The main register may not be visible and hence not directly accessible in all cases.
3.3.5 Tasks
Tasks are used to trigger actions in a peripheral, for example to start a particular behavior. A peripheral can
implement multiple tasks with each task having a separate register in that peripheral's task register group.
4418_1315 v1.0
16
Product overview
A task is triggered when firmware writes 1 to the task register, or when the peripheral itself or another
peripheral toggles the corresponding task signal. See the figure Tasks, events, shortcuts, publish, subscribe
and interrupts on page 15.
3.3.6 Events
Events are used to notify peripherals and the CPU about events that have happened, for example a state
change in a peripheral. A peripheral may generate multiple events, where each event has a separate
register in that peripheral's event register group.
An event is generated when the peripheral itself toggles the corresponding event signal, and the event
register is updated to reflect that the event has been generated (see figure Tasks, events, shortcuts,
publish, subscribe and interrupts on page 15). An event register is only cleared when firmware writes 0
to it. Events can be generated by the peripheral even when the event register is set to 1.
3.3.7 Publish / Subscribe
Events and tasks from different peripherals can be connected together through the DPPI. See Tasks,
events, shortcuts, publish, subscribe and interrupts on page 15. This is done through publish /
subscribe registers in each peripheral. An event can be published onto a DPPI channel by configuring
the event's PUBLISH register. Similarly a task can subscribe to a DPPI channel by configuring the task's
SUBSCRIBE register.
See DPPI - Distributed programmable peripheral interconnect on page 82 for details.
3.3.8 Shortcuts
A shortcut is a direct connection between an event and a task within the same peripheral. If a shortcut is
enabled, the associated task is automatically triggered when its associated event is generated.
Using shortcuts is equivalent to making the connection outside the peripheral and through the DPPI.
However, the propagation delay when using shortcuts is usually shorter than the propagation delay
through the DPPI.
Shortcuts are predefined, which means that their connections cannot be configured by firmware. Each
shortcut can be individually enabled or disabled through the shortcut register, one bit per shortcut, giving
a maximum of 32 shortcuts for each peripheral.
3.3.9 Interrupts
All peripherals support interrupts. Interrupts are generated by events.
A peripheral only occupies one interrupt, and the interrupt number follows the peripheral ID. For example,
the peripheral with ID=4 is connected to interrupt number 4 in the nested vectored interrupt controller
(NVIC).
Using registers INTEN, INTENSET, and INTENCLR, every event generated by a peripheral can be
configured to generate that peripheral's interrupt. Multiple events can be enabled to generate interrupts
simultaneously. To resolve the correct interrupt source, the event registers in the event group of
peripheral registers will indicate the source.
Some peripherals implement only INTENSET and INTENCLR registers, and the INTEN register is not
available on those peripherals. See the individual peripheral chapters for details. In all cases, reading back
the INTENSET or INTENCLR register returns the same information as in INTEN.
Each event implemented in the peripheral is associated with a specific bit position in the INTEN, INTENSET
and INTENCLR registers.
The relationship between tasks, events, shortcuts, and interrupts is illustrated in figure Tasks, events,
shortcuts, publish, subscribe and interrupts on page 15.
4418_1315 v1.0
17
Product overview
Interrupt clearing
Interrupts should always be cleared.
Clearing an interrupt by writing 0 to an event register, or disabling an interrupt using the INTENCLR
register, may take a number of CPU clock cycles to take effect. This means that an interrupt may reoccur
immediately, even if a new event has not come, if the program exits an interrupt handler after the
interrupt is cleared or disabled but before it has taken effect.
Note: To avoid an interrupt reoccurring before a new event has come, the program should perform
a read from one of the peripheral registers. For example, the event register that has been cleared,
or the INTENCLR register that has been used to disable the interrupt.
Care should be taken to ensure that the compiler does not remove the read operation as an optimization.
3.3.10 Secure/non-secure peripherals
For some peripherals, the security configuration can change from secure to non-secure, or vice versa. Care
must be taken when changing the security configuration of a peripheral, to prevent security information
leakage and ensure correct operation.
The following sequence should be followed, where applicable, when configuring and changing the security
settings of a peripheral in the SPU - System protection unit on page 260:
1.
2.
3.
4.
5.
6.
7.
Stop peripheral operation
Disable the peripheral
Remove pin connections
Disable DPPI connections
Clear sensitive registers (e.g. writing back default values)
Change peripheral security setting in the SPU - System protection unit on page 260
Re-enable the peripheral
4418_1315 v1.0
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4
Application core
4.1 CPU
The ARM® Cortex-M33 processor has a 32-bit instruction set (Thumb®-2 technology) that implements a
superset of 16 and 32-bit instructions to maximize code density and performance.
This processor implements several features that enable energy-efficient arithmetic and high-performance
signal processing, including:
•
•
•
•
•
•
•
Digital signal processing (DSP) instructions
Single-cycle multiply and accumulate (MAC) instructions
Hardware divide
8- and 16-bit single instruction, multiple data (SIMD) instructions
Single-precision floating-point unit (FPU)
Memory Protection Unit (MPU)
ARM® TrustZone® for ARMv8-M
The ARM® Cortex Microcontroller Software Interface Standard (CMSIS) hardware abstraction layer for the
ARM® Cortex processor series is implemented and available for the M33 CPU.
Real-time execution is highly deterministic in thread mode, to and from sleep modes, and when handling
events at configurable priority levels via the nested vectored interrupt controller (NVIC).
Executing code from internal or external flash will have a wait state penalty. The instruction cache can
be enabled to minimize flash wait states when fetching instructions. For more information on cache,
see Cache on page 31. The section Electrical specification on page 20 shows CPU performance
parameters including the wait states in different modes, CPU current and efficiency, and processing power
and efficiency based on the CoreMark® benchmark.
4.1.1 CPU and support module configuration
The ARM® Cortex®-M33 processor has a number of CPU options and support modules implemented on
the device.
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Application core
Option / Module
Description
Implemented
Core options
NVIC
Nested vectored interrupt controller
PRIORITIES
Priority bits
3
WIC
Wake-up interrupt controller
NO
Endianness
Memory system endianness
Little endian
DWT
Data watchpoint and trace
YES
MPU_NS
Number of non-secure memory protection unit (MPU) regions
16
MPU_S
Number of secure MPU regions
16
SAU
Number of security attribution unit (SAU) regions
0, see SPU for more information about
Modules
secure regions.
FPU
Floating-point unit
YES
DSP
Digital signal processing extension
YES
ARMv8-M TrustZone
ARMv8-M security extensions
YES
CPIF
Co-processor interface
NO
ETM
Embedded trace macrocell
YES
ITM
Instrumentation trace macrocell
YES
MTB
Micro trace buffer
NO
CTI
Cross trigger interface
YES
BPU
Breakpoint unit
YES
HTM
AMBA AHB trace macrocell
®
™
NO
4.1.2 Electrical specification
4.1.2.1 CPU performance
The CPU clock speed is 64 MHz. Current and efficiency data is taken when in System ON and the CPU is
executing the CoreMark™ benchmark. It includes power regulator and clock base currents. All other blocks
are IDLE.
Symbol
Description
Min.
WFLASH
CPU wait states, running from flash, cache disabled
0
Typ.
Max.
4
WFLASHCACHE
CPU wait states, running from flash, cache enabled
0
2
WRAM
CPU wait states, running from RAM
Units
0
CMFLASH
CoreMark , running from flash, cache enabled
243
CoreMark
CMFLASH/MHz
CoreMark per MHz, running from flash, cache enabled
3.79
CoreMark/
CMFLASH/mA
CoreMark per mA, running from flash, cache enabled, DC/
84
1
MHz
DC
CoreMark/
mA
4.2 Memory
The application microcontroller has embedded 1024 kB flash and 256 kB RAM for application code and
data storage.
As illustrated in Memory layout on page 21, both CPU and EasyDMA are able to access RAM via the
AHB multilayer interconnect. See AHB multilayer interconnect on page 47 and EasyDMA on page
44 for more information about AHB multilayer interconnect and EasyDMA respectively. The LTE
modem can access all application MCU memory, but typically a small portion of RAM is dedicated to data
exchange between application MCU and the modem baseband controller.
1
Using IAR compiler
4418_1315 v1.0
20
Application core
EasyDMA
AHB master
CPU
ARM® Cortex®-M33
DMA bus
System bus
Modem
Code bus
Peripheral
Section 3
APB2APB
RAM7
Section 2
AHB slave
Section 1
Section 0
Section 3
RAM6
Section 2
AHB slave
Section 1
Section 0
Section 3
RAM5
Section 2
AHB slave
Section 1
Section 0
Section 3
RAM4
Section 2
AHB slave
Section 1
Section 0
Section 3
RAM3
Section 2
AHB slave
Section 1
Section 0
Section 3
RAM2
Section 2
AHB slave
Section 1
0x2003 6000
0x2003 4000
0x2003 2000
0x2003 0000
0x2002 E000
0x2002 C000
0x2002 A000
0x2002 8000
0x2002 6000
0x2002 4000
0x2002 2000
0x2002 0000
0x2001 E000
0x2001 C000
0x2001 A000
0x2001 8000
0x2001 6000
0x2001 4000
Section 3
0x2000 E000
Section 2
AHB slave
Section 1
Section 3
RAM0
Section 2
AHB slave
Section 1
Section 0
Page 255
0x2000 C000
0x2000 A000
0x2000 8000
0x2000 6000
0x2000 4000
0x2000 2000
0x2000 0000
0x000F F000
Cache
AHB slave
Page 3..254
0x0000 3000
Page 2
0x0000 2000
Page 1
0x0000 1000
Page 0
0x0000 0000
Figure 3: Memory layout
RAM - Random access memory
RAM can be read and written an unlimited number of times by the CPU and the EasyDMA.
Each RAM AHB slave is connected to one or more RAM sections. See Memory layout on page 21 for
more information.
21
0x2003 8000
0x2001 2000
0x2001 0000
Section 0
4418_1315 v1.0
0x2003 C000
0x2003 A000
Section 0
RAM1
AHB multilayer interconnect
0x2003 E000
Application core
The RAM blocks power states and retention states in System ON and System OFF modes are controlled by
the VMC.
Flash - Non-volatile memory
Flash can be read an unlimited number of times by the CPU and is accessible via the AHB interface
connected to the CPU, see Memory layout on page 21 for more information. There are restrictions on
the number of times flash can be written and erased, and also on how it can be written. Writing to flash is
managed by the non-volatile memory controller (NVMC).
4.2.1 Memory map
All memory and registers are found in the same address space, as illustrated in the device memory map
below.
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Application core
System address map
Address map
0xFFFF FFFF
Private peripheral bus
0xE000 0000
Device
0xC000 0000
ROM table
MCU ROM table
0xE00F F000
0xE00F E000
Reserved (MTB)
CTI
ETM
Reserved (TPIU)
0xE004 3000
0xE004 2000
0xE004 1000
0xE004 0000
SCS
BPU
DWT
ITM
0xE000 E000
0xE000 2000
0xE000 1000
0xE000 0000
AHB peripherals
0x5080 0000
Device
0xA000 0000
RAM
0x8000 0000
RAM
0x6000 0000
Secure peripheral
APB peripherals
0x5000 0000
Non-secure peripheral
AHB peripherals
APB peripherals
0x4000 0000
0X5000 0000
0x4080 0000
0x4000 0000
SRAM
0x2000 0000
Code
0x0000 0000
SRAM
0x2000 0000
UICR
0x00FF 8000
FICR
0x00FF 0000
FLASH
0x0000 0000
Figure 4: Memory map
Some of the registers are retained (their values kept). Read more about retained registers in Retained
registers on page 55 and Reset behavior on page 55.
4.2.2 Instantiation
ID
Base address
Peripheral
Instance
Secure mapping DMA security
Description
3
0x50003000
SPU
SPU
S
System Protection Unit
4418_1315 v1.0
NA
23
Application core
ID
4
5
5
6
8
8
8
8
8
9
9
9
9
9
10
10
10
10
10
11
11
11
11
11
13
14
15
Base address
0x50004000
0x40004000
0x50005000
0x40005000
0x50005000
0x40005000
0x50006000
0x50008000
0x40008000
0x50008000
0x40008000
0x50008000
0x40008000
0x50008000
0x40008000
0x50008000
0x40008000
0x50009000
0x40009000
0x50009000
0x40009000
0x50009000
0x40009000
0x50009000
0x40009000
0x50009000
0x40009000
0x5000A000
0x4000A000
0x5000A000
0x4000A000
0x5000A000
0x4000A000
0x5000A000
0x4000A000
0x5000A000
0x4000A000
0x5000B000
0x4000B000
0x5000B000
0x4000B000
0x5000B000
0x4000B000
0x5000B000
0x4000B000
0x5000B000
0x4000B000
0x5000D000
0x5000E000
0x4000E000
0x5000F000
0x4000F000
4418_1315 v1.0
Peripheral
REGULATORS
CLOCK
POWER
CTRLAPPERI
SPIM
SPIS
TWIM
TWIS
UARTE
SPIM
SPIS
TWIM
TWIS
UARTE
SPIM
SPIS
TWIM
TWIS
UARTE
SPIM
SPIS
TWIM
TWIS
UARTE
GPIOTE
SAADC
TIMER
Instance
REGULATORS : S
REGULATORS : NS
CLOCK : S
CLOCK : NS
POWER : S
POWER : NS
CTRL_AP_PERI
SPIM0 : S
SPIM0 : NS
SPIS0 : S
SPIS0 : NS
TWIM0 : S
TWIM0 : NS
TWIS0 : S
TWIS0 : NS
UARTE0 : S
UARTE0 : NS
SPIM1 : S
SPIM1 : NS
SPIS1 : S
SPIS1 : NS
TWIM1 : S
TWIM1 : NS
TWIS1 : S
TWIS1 : NS
UARTE1 : S
UARTE1 : NS
SPIM2 : S
SPIM2 : NS
SPIS2 : S
SPIS2 : NS
TWIM2 : S
TWIM2 : NS
TWIS2 : S
TWIS2 : NS
UARTE2 : S
UARTE2 : NS
SPIM3 : S
SPIM3 : NS
SPIS3 : S
SPIS3 : NS
TWIM3 : S
TWIM3 : NS
TWIS3 : S
TWIS3 : NS
UARTE3 : S
UARTE3 : NS
GPIOTE0
SAADC : S
SAADC : NS
TIMER0 : S
TIMER0 : NS
Secure mapping DMA security
Description
US
NA
Regulator configuration
US
NA
Clock control
US
NA
Power control
S
NA
CTRL-AP-PERI
US
SA
SPI master 0
US
SA
SPI slave 0
US
SA
Two-wire interface master 0
US
SA
Two-wire interface slave 0
US
SA
US
SA
SPI master 1
US
SA
SPI slave 1
US
SA
Two-wire interface master 1
US
SA
Two-wire interface slave 1
US
SA
US
SA
SPI master 2
US
SA
SPI slave 2
US
SA
Two-wire interface master 2
US
SA
Two-wire interface slave 2
US
SA
US
SA
SPI master 3
US
SA
SPI slave 3
US
SA
Two-wire interface master 3
US
SA
Two-wire interface slave 3
US
SA
S
NA
Secure GPIO tasks and events
US
SA
Analog to digital converter
US
NA
Timer 0
24
Universal asynchronous receiver/transmitter
with EasyDMA 0
Universal asynchronous receiver/transmitter
with EasyDMA 1
Universal asynchronous receiver/transmitter
with EasyDMA 2
Universal asynchronous receiver/transmitter
with EasyDMA 3
Application core
ID
16
17
20
21
23
24
27
28
29
30
31
32
33
34
35
36
38
40
42
44
49
57
57
58
Base address
0x50010000
0x40010000
0x50011000
0x40011000
0x50014000
0x40014000
0x50015000
0x40015000
0x50017000
0x40017000
0x50018000
0x40018000
0x5001B000
0x4001B000
0x5001C000
0x4001C000
0x5001D000
0x4001D000
0x5001E000
0x4001E000
0x5001F000
0x4001F000
0x50020000
0x40020000
0x50021000
0x40021000
0x50022000
0x40022000
0x50023000
0x40023000
0x50024000
0x40024000
0x50026000
0x40026000
0x50028000
0x40028000
0x5002A000
0x4002A000
0x5002C000
0x4002C000
0x40031000
0x50039000
0x40039000
0x50039000
0x40039000
0x5003A000
0x4003A000
Peripheral
TIMER
TIMER
RTC
RTC
DPPIC
WDT
EGU
EGU
EGU
EGU
EGU
EGU
PWM
PWM
PWM
PWM
PDM
I2S
IPC
FPU
GPIOTE
KMU
NVMC
VMC
Instance
TIMER1 : S
TIMER1 : NS
TIMER2 : S
TIMER2 : NS
RTC0 : S
RTC0 : NS
RTC1 : S
RTC1 : NS
DPPIC : S
DPPIC : NS
WDT : S
WDT : NS
EGU0 : S
EGU0 : NS
EGU1 : S
EGU1 : NS
EGU2 : S
EGU2 : NS
EGU3 : S
EGU3 : NS
EGU4 : S
EGU4 : NS
EGU5 : S
EGU5 : NS
PWM0 : S
PWM0 : NS
PWM1 : S
PWM1 : NS
PWM2 : S
PWM2 : NS
PWM3 : S
PWM3 : NS
PDM : S
PDM : NS
I2S : S
I2S : NS
IPC : S
IPC : NS
FPU : S
FPU : NS
GPIOTE1
KMU : S
KMU : NS
NVMC : S
NVMC : NS
VMC : S
VMC : NS
Secure mapping DMA security
Description
US
NA
Timer 1
US
NA
Timer 2
US
NA
Real time counter 0
US
NA
Real time counter 1
SPLIT
NA
DPPI configuration
US
NA
Watchdog timer
US
NA
Event generator unit 0
US
NA
Event generator unit 1
US
NA
Event generator unit 2
US
NA
Event generator unit 3
US
NA
Event generator unit 4
US
NA
Event generator unit 5
US
SA
Pulse width modulation unit 0
US
SA
Pulse width modulation unit 1
US
SA
Pulse width modulation unit 2
US
SA
Pulse width modulation unit 3
US
SA
US
SA
Inter-IC Sound
US
NA
Interprocessor communication
US
NA
Floating-point unit
NS
NA
Non Secure GPIO tasks and events
SPLIT
NA
Key management unit
SPLIT
NA
Non-volatile memory controller
US
NA
Volatile memory controller
Pulse density modulation (digital microphone)
interface
64
0x50840000
CC_HOST_RGF
CC_HOST_RGF
S
NSA
Host platform interface
64
0x50840000
CRYPTOCELL
CRYPTOCELL
S
NSA
CryptoCell sub-system control interface
SPLIT
NA
General purpose input and output
66
0x50842500
0x40842500
GPIO
P0 : S
P0 : NS
N/A 0x00FF0000
FICR
FICR
S
NA
Factory information configuration
N/A 0x00FF8000
UICR
UICR
S
NA
User information configuration
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25
Application core
ID
Base address
N/A 0xE0080000
Peripheral
Instance
Secure mapping DMA security
Description
TAD
TAD
S
Trace and debug control
NA
Table 4: Instantiation table
4.2.3 Peripheral access control capabilities
Information about the peripheral access control capabilities can be found in the instantiation table.
The instantiation table has two columns containing the information about access control capabilities for a
peripheral:
• Secure mapping: This column defines configuration capabilities for TrustZone®-M secure attribute.
• DMA security: This column indicates if the peripheral has DMA capabilities, and if DMA transfer can be
assigned to a different security attribute than the peripheral itself.
For details on options in secure mapping column and DMA security column, see the following tables
respecitvely.
Abbreviation
Description
NS
Non-secure: This peripheral is always accessible as a non-secure peripheral.
S
Secure: This peripheral is always accessible as a secure peripheral.
US
User-selectable: Non-secure or secure attribute for this peripheral is defined by the
PERIPHID[0].PERM register.
SPLIT
Both non-secure and secure: The same resource is shared by both secure and nonsecure code.
Table 5: Secure mapping column options
Abbreviation
Description
NA
Not applicable: Peripheral has no DMA capability.
NSA
No separate attribute: Peripheral has DMA, and DMA transfers always have the same
security attribute as assigned to the peripheral.
SA
Separate attribute: Peripheral has DMA, and DMA transfers can have a different security
attribute than the one assigned to the peripheral.
Table 6: DMA security column options
4.3 VMC — Volatile memory controller
The volatile memory controller (VMC) provides power control of RAM blocks.
Each of the available RAM blocks, which can contain multiple RAM sections, can be turned on or off
independently in System ON mode, using the RAM[n]registers. These registers also control if a RAM block,
or some of its sections, is retained in System OFF mode. See Memory chapter for more information about
RAM blocks and sections.
Note: Powering up a RAM block takes a few clock cycles. Thus, it is recommended reading the
POWER register before accessing a RAM block that has been recently powered on.
4418_1315 v1.0
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Application core
4.3.1 Registers
Base address Peripheral
Instance
0x5003A000
VMC : S
0x4003A000
VMC
VMC : NS
Secure mapping
DMA security
Description
US
NA
Volatile memory controller
Table 7: Instances
Register
Offset
RAM[0].POWER
0x600
Security
Description
RAM0 power control register
RAM[0].POWERSET
0x604
RAM0 power control set register
RAM[0].POWERCLR
0x608
RAM0 power control clear register
RAM[1].POWER
0x610
RAM1 power control register
RAM[1].POWERSET
0x614
RAM1 power control set register
RAM[1].POWERCLR
0x618
RAM1 power control clear register
RAM[2].POWER
0x620
RAM2 power control register
RAM[2].POWERSET
0x624
RAM2 power control set register
RAM[2].POWERCLR
0x628
RAM2 power control clear register
RAM[3].POWER
0x630
RAM3 power control register
RAM[3].POWERSET
0x634
RAM3 power control set register
RAM[3].POWERCLR
0x638
RAM3 power control clear register
RAM[4].POWER
0x640
RAM4 power control register
RAM[4].POWERSET
0x644
RAM4 power control set register
RAM[4].POWERCLR
0x648
RAM4 power control clear register
RAM[5].POWER
0x650
RAM5 power control register
RAM[5].POWERSET
0x654
RAM5 power control set register
RAM[5].POWERCLR
0x658
RAM5 power control clear register
RAM[6].POWER
0x660
RAM6 power control register
RAM[6].POWERSET
0x664
RAM6 power control set register
RAM[6].POWERCLR
0x668
RAM6 power control clear register
RAM[7].POWER
0x670
RAM7 power control register
RAM[7].POWERSET
0x674
RAM7 power control set register
RAM[7].POWERCLR
0x678
RAM7 power control clear register
Table 8: Register overview
4.3.1.1 RAM[n].POWER (n=0..7)
Address offset: 0x600 + (n × 0x10)
RAMn power control register
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Configuration
Application core
Bit number
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 6 5 4 3 2 1 0
ID
H G F E
Reset 0x0000FFFF
ID
Access
Field
A-D
RW S[i]POWER (i=0..3)
D C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
Keep RAM section Si of RAM n on or off in System ON mode
All RAM sections will be switched off in System OFF mode
E-H
Off
0
Off
On
1
On
RW S[i]RETENTION (i=0..3)
Keep retention on RAM section Si of RAM n when RAM
section is switched off
Off
0
Off
On
1
On
4.3.1.2 RAM[n].POWERSET (n=0..7)
Address offset: 0x604 + (n × 0x10)
RAMn power control set register
When read, this register will return the value of the POWER register.
Bit number
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 6 5 4 3 2 1 0
ID
H G F E
Reset 0x0000FFFF
ID
Access
Field
A-D
W
S[i]POWER (i=0..3)
E-H
W
S[i]RETENTION (i=0..3)
D C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
Keep RAM section Si of RAM n on or off in System ON mode
On
1
On
Keep retention on RAM section Si of RAM n when RAM
section is switched off
On
1
On
4.3.1.3 RAM[n].POWERCLR (n=0..7)
Address offset: 0x608 + (n × 0x10)
RAMn power control clear register
When read, this register will return the value of the POWER register.
Bit number
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 6 5 4 3 2 1 0
ID
H G F E
Reset 0x0000FFFF
ID
Access
Field
A-D
W
E-H
W
D C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Off
1
Description
S[i]POWER (i=0..3)
Keep RAM section Si of RAM n on or off in System ON mode
Off
S[i]RETENTION (i=0..3)
Keep retention on RAM section Si of RAM n when RAM
section is switched off
Off
1
Off
4.4 NVMC — Non-volatile memory controller
The non-volatile memory controller (NVMC) is used for writing and erasing of the internal flash memory
and the user information configuration register (UICR).
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The NVMC is a split security peripheral. This means that when the NVMC is configured as non-secure, only
a subset of the registers is available from the non-secure code. See SPU - System protection unit on page
260 and Registers on page 31 for more details.
When the NVMC is configured to be a secure peripheral, only secure code has access.
Before a write can be performed, the NVMC must be enabled for writing in CONFIG.WEN. Similarly, before
an erase can be performed, the NVMC must be enabled for erasing in CONFIG.EEN, see CONFIG on page
32. The user must make sure that writing and erasing are not enabled at the same time. Failing to do
so may result in unpredictable behavior.
4.4.1 Writing to flash
When writing is enabled, in CONFIG register for secure region, or in CONFIGNS register for non-secure
region, flash is written by writing a full 32-bit word to a word-aligned address in flash.
Secure code has access to both secure and non-secure regions, by using the appropriate configuration of
CONFIG and CONFIGNS registers. Non-secure code, in constrast, has access to non-secure regions only.
Thus, non-secure code only needs CONFIGNS.
The NVMC is only able to write '0' to erased bits in flash, that is bits set to '1'. It cannot write a bit back to
'1'.
As illustrated in Memory on page 20, flash is divided into multiple pages. The same address in flash can
only be written nWRITE number of times before a page erase must be performed.
Only full 32-bit words can be written to flash using the NVMC interface. To write less than 32 bits to flash,
write the data as a word, and set all the bits that should remain unchanged in the word to '1'. Note that
the restriction about the number of writes (see above) still applies in this case.
The time it takes to write a word to flash is specified by tWRITE. If CPU executes code from flash while the
NVMC is writing to flash, the CPU will be stalled.
Only word-aligned writes are allowed. Byte or half-word-aligned writes will result in a bus fault.
4.4.2 Erasing a secure page in flash
When secure region erase is enabled (in CONFIG register), a flash page can be erased by writing
0xFFFFFFFF into the first 32-bit word in a flash page.
Page erase is only applicable to the code area in the flash and does not work with UICR.
After erasing a flash page, all bits in the page are set to '1'. The time it takes to erase a page is specified by
tERASEPAGE. The CPU is stalled if the CPU executes code from the flash while the NVMC performs the erase
operation.
See Partial erase of a page in flash for information on splitting the erase time in smaller chunks.
4.4.3 Erasing a non-secure page in flash
When non-secure region erase is enabled, a non-secure flash page can be erased by writing 0xFFFFFFFF
into the first 32-bit word of the flash page.
Page erase is only applicable to the code area in the flash and does not work with UICR.
After erasing a flash page, all bits in the page are set to '1'. The time it takes to erase a page is specified by
tERASEPAGE. The CPU is stalled if the CPU executes code from the flash while the NVMC performs the erase
operation.
4.4.4 Writing to user information configuration registers (UICR)
User information configuration registers (UICR) are written in the same way as flash. After UICR has been
written, the new UICR configuration will only take effect after a reset.
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UICR is only accessible by secure code. Any write from non-secure code will be faulted. In order to lock the
chip after uploading non-secure code, non-secure debugger needs to use the WRITEUICRNS register inside
the NVMC in order to set APPROTECT (APPROTECT will be written to 0x00000000).
UICR can only be written nWRITE number of times before an erase must be performed using ERASEALL.
The time it takes to write a word to the UICR is specified by tWRITE. The CPU is stalled if the CPU executes
code from the flash while the NVMC is writing to the UICR.
4.4.5 Erase all
When erase is enabled, the whole flash and UICR can be erased in one operation by using the ERASEALL
register. ERASEALL will not erase the factory information configuration registers (FICR).
This functionality can be blocked by some configuration of the UICR protection bits, see the table NVMC
protection (1 - Enabled, 0 - Disabled, X - Don't care) on page 30.
The time it takes to perform an ERASEALL on page 32 command is specified by tERASEALL. The CPU is
stalled if the CPU executes code from the flash while the NVMC performs the erase operation.
4.4.6 NVMC protection mechanisms
This chapter describes the different protection mechanisms for the non-volatile memory.
4.4.6.1 NVMC blocking
UICR integrity is assured through use of multiple levels of protection. UICR protection bits can be
configured to allow or block certain operations.
The table below shows the different status of UICR protection bits, and which operations are allowed or
blocked.
UICR protection bit status
SECUREAPPROTECT APPROTECT
ERASEPROTECT
NVMC protection
CTRL-AP
NVMC
ERASEALL
ERASEALL
0
0
0
Available
Available
1
X
0
Available
Blocked
X
1
0
Available
Blocked
X
X
1
Blocked
Blocked
Table 9: NVMC protection (1 - Enabled, 0 - Disabled, X - Don't care)
Note: Erase can still be performed through CTRL-AP, regardless of the above settings. See CTRL-AP
- Control access port on page 374 for more information.
Uploading code with secure debugging blocked
Non-secure code can program non-secure flash regions. In order to perform these operations, the NVMC
has the following non-secure registers: CONFIGNS, READY and READYNEXT.
Register CONFIGNS on page 34 works as the CONFIG register but it is used only for non-secure
transactions. Both page erase and writing inside the flash require a write transaction (see Erasing a secure
page in flash on page 29 or Erasing a non-secure page in flash on page 29). Because of this, the
SPU - System protection unit on page 260 will guarantee that the non-secure code cannot write inside a
secure page, since the transaction will never reach the NVMC controller.
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4.4.6.2 NVMC power failure protection
NVMC power failure protection is possible through use of power-fail comparator that is monitoring power
supply.
If the power-fail comparator is enabled, and the power supply voltage is below VPOF threshold, the powerfail comparator will prevent the NVMC from performing erase or write operations in non-volatile memory
(NVM).
If a power failure warning is present at the start of an NVM write or erase operation, the NVMC will block
the operation and a bus error will be signalled. If a power failure warning occurs during an ongoing NVM
write operation, the NVMC will try to finish the operation. And if the power failure warning persists,
consecutive NVM write operations will be blocked by the NVMC, and a bus error will be signalled. If a
power failure warning occurs during an NVM erase operation, the operation is aborted and a bus error is
signalled.
4.4.7 Cache
An instruction cache (I-Cache) can be enabled for the ICODE bus in the NVMC.
See Memory map on page 22 for the location of flash.
A cache hit is an instruction fetch from the cache, and it has a 0 wait-state delay. The number of waitstates for a cache miss, where the instruction is not available in the cache and needs to be fetched from
flash, depends on the processor frequency and is shown in CPU on page 19.
Enabling the cache can increase the CPU performance, and reduce power consumption by reducing the
number of wait cycles and the number of flash accesses. This will depend on the cache hit rate. Cache
draws current when enabled. If the reduction in average current due to reduced flash accesses is larger
than the cache power requirement, the average current to execute the program code will be reduced.
When disabled, the cache does not draw current and its content is not retained.
It is possible to enable cache profiling to analyze the performance of the cache for your program using
the register ICACHECNF. When profiling is enabled, registers IHIT and IMISS are incremented for every
instruction cache hit or miss respectively.
4.4.8 Registers
Base address Peripheral
Instance
0x50039000
NVMC : S
0x40039000
NVMC
NVMC : NS
Secure mapping
DMA security
SPLIT
NA
Description
Non-volatile memory
controller
Table 10: Instances
Register
Offset
Security
Description
READY
0x400
NS
Ready flag
READYNEXT
0x408
NS
Ready flag
CONFIG
0x504
S
Configuration register
ERASEALL
0x50C
S
Register for erasing all non-volatile user memory
ERASEPAGEPARTIALCFG
0x51C
S
Register for partial erase configuration
ICACHECNF
0x540
S
I-code cache configuration register
IHIT
0x548
S
I-code cache hit counter
IMISS
0x54C
S
I-code cache miss counter
CONFIGNS
0x584
NS
WRITEUICRNS
0x588
NS
Non-secure APPROTECT enable register
Table 11: Register overview
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4.4.8.1 READY
Address offset: 0x400
Ready flag
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000001
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
Busy
0
NVMC is busy (on-going write or erase operation)
Ready
1
NVMC is ready
READY
NVMC is ready or busy
4.4.8.2 READYNEXT
Address offset: 0x408
Ready flag
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000001
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
Busy
0
NVMC cannot accept any write operation
Ready
1
NVMC is ready
READYNEXT
NVMC can accept a new write operation
4.4.8.3 CONFIG
Address offset: 0x504
Configuration register
This register is one hot
Bit number
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 6 5 4 3 2 1 0
ID
A A A
Reset 0x00000000
ID
Access
Field
A
RW WEN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Program memory access mode. It is strongly recommended
to only activate erase and write modes when they are
actively used.
Enabling write or erase will invalidate the cache and keep it
invalidated.
Ren
0
Read only access
Wen
1
Write enabled
Een
2
Erase enabled
PEen
4
Partial erase enabled
4.4.8.4 ERASEALL
Address offset: 0x50C
Register for erasing all non-volatile user memory
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
ERASEALL
Erase all non-volatile memory including UICR registers.
Note that erasing must be enabled by setting CONFIG.WEN
= Een before the non-volatile memory can be erased.
NoOperation
0
No operation
Erase
1
Start chip erase
4.4.8.5 ERASEPAGEPARTIALCFG
Address offset: 0x51C
Register for partial erase configuration
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A
Reset 0x0000000A
ID
Access
Field
A
RW DURATION
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0
Value ID
Value
Description
Duration of the partial erase in milliseconds
The user must ensure that the total erase time is long
enough for a complete erase of the flash page
4.4.8.6 ICACHECNF
Address offset: 0x540
I-code cache configuration register
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CACHEEN
B
A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable cache. Invalidates all cache entries.
Enabled
1
Enable cache
Cache enable
RW CACHEPROFEN
Cache profiling enable
Disabled
0
Disable cache profiling
Enabled
1
Enable cache profiling
4.4.8.7 IHIT
Address offset: 0x548
I-code cache hit counter
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW HITS
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Number of cache hits
Write zero to clear
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4.4.8.8 IMISS
Address offset: 0x54C
I-code cache miss counter
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW MISSES
Value ID
Value
Description
Number of cache misses
Write zero to clear
4.4.8.9 CONFIGNS
Address offset: 0x584
This register is one hot
Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000000
ID
Access
Field
A
RW WEN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Program memory access mode. It is strongly recommended
to only activate erase and write modes when they are
actively used.
Enabling write or erase will invalidate the cache and keep it
invalidated.
Ren
0
Read only access
Wen
1
Write enabled
Een
2
Erase enabled
4.4.8.10 WRITEUICRNS
Address offset: 0x588
Non-secure APPROTECT enable register
Bit number
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 6 5 4 3 2 1 0
ID
B B B B B B B B B B B B B B B B B B B B B B B B B B B B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
W
B
W
Value ID
Value
Set
1
Keyvalid
0xAFBE5A7
Description
SET
Allow non-secure code to set APPROTECT
Set value
KEY
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Key to write in order to validate the write operation
Key value
34
A
Application core
4.4.9 Electrical specification
4.4.9.1 Flash programming
Symbol
Description
nWRITE
Number of times a 32-bit word can be written before erase
Min.
Typ.
Max.
Units
nENDURANCE
Erase cycles per page
tWRITE
Time to write one 32-bit word
43
µs
tERASEPAGE
Time to erase one page
87
ms
tERASEALL
Time to erase all flash
173
ms
1.08
ms
Max.
Units
2
10,000
tERASEPAGEPARTIAL,setup Setup time for one partial erase
4.4.9.2 Cache size
Symbol
Description
SizeICODE
I-Code cache size
Min.
Typ.
2048
Bytes
4.5 FICR — Factory information configuration registers
Factory information configuration registers (FICR) are pre-programmed in factory and cannot be erased by
the user. These registers contain chip-specific information and configuration.
4.5.1 Registers
Base address Peripheral
Instance
Secure mapping
DMA security
Description
0x00FF0000
FICR
S
NA
Factory information
FICR
Configuration
configuration
Table 12: Instances
Register
Offset
INFO.DEVICEID[0]
0x204
Device identifier
INFO.DEVICEID[1]
0x208
Device identifier
INFO.PART
0x20C
Part code
INFO.VARIANT
0x210
Part Variant, Hardware version and Production configuration
INFO.PACKAGE
0x214
Package option
INFO.RAM
0x218
RAM variant
INFO.FLASH
0x21C
Flash variant
INFO.CODEPAGESIZE
0x220
Code memory page size
INFO.CODESIZE
0x224
Code memory size
INFO.DEVICETYPE
0x228
Device type
TRIMCNF[n].ADDR
0x300
Address
TRIMCNF[n].DATA
0x304
Data
TRNG90B.BYTES
0xC00
Amount of bytes for the required entropy bits
TRNG90B.RCCUTOFF
0xC04
Repetition counter cutoff
TRNG90B.APCUTOFF
0xC08
Adaptive proportion cutoff
TRNG90B.STARTUP
0xC0C
Amount of bytes for the startup tests
TRNG90B.ROSC1
0xC10
Sample count for ring oscillator 1
TRNG90B.ROSC2
0xC14
Sample count for ring oscillator 2
TRNG90B.ROSC3
0xC18
Sample count for ring oscillator 3
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Register
Offset
TRNG90B.ROSC4
0xC1C
Security
Description
Sample count for ring oscillator 4
Table 13: Register overview
4.5.1.1 INFO.DEVICEID[n] (n=0..1)
Address offset: 0x204 + (n × 0x4)
Device identifier
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
DEVICEID
64 bit unique device identifier
DEVICEID[0] contains the least significant bits of the device
identifier. DEVICEID[1] contains the most significant bits of
the device identifier.
4.5.1.2 INFO.PART
Address offset: 0x20C
Part code
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00009160
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 1 0 1 1 0 0 0 0 0
ID
Access
Field
A
R
Value ID
Value
N9160
0x9160
Description
PART
Part code
nRF9160
4.5.1.3 INFO.VARIANT
Address offset: 0x210
Part Variant, Hardware version and Production configuration
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x0FFFFFFF
ID
Access
Field
A
R
0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
VARIANT
Part Variant, Hardware version and Production
configuration, encoded as ASCII
AAAA
0x41414141
AAAA
AAA0
0x41414130
AAA0
4.5.1.4 INFO.PACKAGE
Address offset: 0x214
Package option
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00002000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
R
Value ID
Value
CC
0x2000
Description
PACKAGE
Package option
CCxx - 236 ball wlCSP
4.5.1.5 INFO.RAM
Address offset: 0x218
RAM variant
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000100
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0
ID
Access
Field
A
R
Value ID
Value
Description
K256
0x100
256 kByte RAM
Unspecified
0xFFFFFFFF
Unspecified
RAM
RAM variant
4.5.1.6 INFO.FLASH
Address offset: 0x21C
Flash variant
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000400
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
Value ID
Value
K1024
0x400
Description
FLASH
Flash variant
1 MByte FLASH
4.5.1.7 INFO.CODEPAGESIZE
Address offset: 0x220
Code memory page size
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00001000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
CODEPAGESIZE
Code memory page size
4.5.1.8 INFO.CODESIZE
Address offset: 0x224
Code memory size
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000100
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0
ID
Access
Field
A
R
Value ID
Value
Description
CODESIZE
Code memory size in number of pages
Total code space is: CODEPAGESIZE * CODESIZE
4.5.1.9 INFO.DEVICETYPE
Address offset: 0x228
Device type
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
R
Value ID
Value
Description
Die
0x0000000
Device is an physical DIE
FPGA
0xFFFFFFFF
Device is an FPGA
DEVICETYPE
Device type
4.5.1.10 TRIMCNF[n].ADDR (n=0..255)
Address offset: 0x300 + (n × 0x8)
Address
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
R
Value ID
Value
Description
Address
Address
4.5.1.11 TRIMCNF[n].DATA (n=0..255)
Address offset: 0x304 + (n × 0x8)
Data
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
Data
Data
4.5.1.12 TRNG90B.BYTES
Address offset: 0xC00
Amount of bytes for the required entropy bits
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
R
Value ID
Value
Description
BYTES
Amount of bytes for the required entropy bits
4.5.1.13 TRNG90B.RCCUTOFF
Address offset: 0xC04
Repetition counter cutoff
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
R
Value ID
Value
Description
RCCUTOFF
Repetition counter cutoff
4.5.1.14 TRNG90B.APCUTOFF
Address offset: 0xC08
Adaptive proportion cutoff
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
APCUTOFF
Adaptive proportion cutoff
4.5.1.15 TRNG90B.STARTUP
Address offset: 0xC0C
Amount of bytes for the startup tests
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000210
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0
Value ID
Value
Description
STARTUP
Amount of bytes for the startup tests
4.5.1.16 TRNG90B.ROSC1
Address offset: 0xC10
Sample count for ring oscillator 1
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
ROSC1
4418_1315 v1.0
Sample count for ring oscillator 1
39
Application core
4.5.1.17 TRNG90B.ROSC2
Address offset: 0xC14
Sample count for ring oscillator 2
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
ROSC2
Sample count for ring oscillator 2
4.5.1.18 TRNG90B.ROSC3
Address offset: 0xC18
Sample count for ring oscillator 3
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
ROSC3
Sample count for ring oscillator 3
4.5.1.19 TRNG90B.ROSC4
Address offset: 0xC1C
Sample count for ring oscillator 4
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
R
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
ROSC4
Sample count for ring oscillator 4
4.6 UICR — User information configuration registers
The user information configuration registers (UICRs) are non-volatile memory (NVM) registers for
configuring user specific settings.
For information on writing UICR registers, see the NVMC — Non-volatile memory controller on page
28 and Memory on page 20 chapters.
4.6.1 Registers
Base address Peripheral
Instance
Secure mapping
DMA security
Description
0x00FF8000
UICR
S
NA
User information
UICR
configuration
Table 14: Instances
4418_1315 v1.0
40
Configuration
Application core
Register
Offset
Security
Description
APPROTECT
0x000
UNUSED0
0x004
Reserved
UNUSED1
0x008
Reserved
UNUSED2
0x00C
Reserved
UNUSED3
0x010
XOSC32M
0x014
Oscillator control
HFXOSRC
0x01C
HFXO clock source selection
HFXOCNT
0x020
HFXO startup counter
SECUREAPPROTECT
0x02C
Secure access port protection
ERASEPROTECT
0x030
Erase protection
OTP[n]
0x108
One time programmable memory
KEYSLOT.CONFIG[n].DEST
0x400
Destination address where content of the key value registers
Access port protection
Reserved
(KEYSLOT.KEYn.VALUE[0-3]) will be pushed by KMU. Note that this address MUST
match that of a peripherals APB mapped write-only key registers, else the KMU
can push this key value into an address range which the CPU can potentially read!
KEYSLOT.CONFIG[n].PERM 0x404
Define permissions for the key slot. Bits 0-15 and 16-31 can only be written when
equal to 0xFFFF.
KEYSLOT.KEY[n].VALUE[0]
0x800
Define bits [31:0] of value assigned to KMU key slot.
KEYSLOT.KEY[n].VALUE[1]
0x804
Define bits [63:32] of value assigned to KMU key slot.
KEYSLOT.KEY[n].VALUE[2]
0x808
Define bits [95:64] of value assigned to KMU key slot.
KEYSLOT.KEY[n].VALUE[3]
0x80C
Define bits [127:96] of value assigned to KMU key slot.
Table 15: Register overview
4.6.1.1 APPROTECT
Address offset: 0x000
Access port protection
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW PALL
Value ID
Value
Description
Blocks debugger read/write access to all CPU registers and
memory mapped addresses
Unprotected
0xFFFFFFFF
Unprotected
Protected
0x00000000
Protected
4.6.1.2 XOSC32M
Address offset: 0x014
Oscillator control
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A
Reset 0xFFFFFFCF
ID
Access
Field
A
RW CTRL
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1
Value ID
Value
Description
Pierce current DAC control signals
4.6.1.3 HFXOSRC
Address offset: 0x01C
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Application core
HFXO clock source selection
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0xFFFFFFFF
ID
Access
Field
A
RW HFXOSRC
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
HFXO clock source selection
XTAL
1
32 MHz crystal oscillator
TCXO
0
32 MHz temperature compensated crystal oscillator (TCXO)
4.6.1.4 HFXOCNT
Address offset: 0x020
HFXO startup counter
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A
Reset 0xFFFFFFFF
ID
Access
Field
A
RW HFXOCNT
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
HFXO startup counter. Total debounce time = HFXOCNT*64
us + 0.5 us
MinDebounceTime
0
Min debounce time = (0*64 us + 0.5 us)
MaxDebounceTime
255
Max debounce time = (255*64 us + 0.5 us)
4.6.1.5 SECUREAPPROTECT
Address offset: 0x02C
Secure access port protection
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW PALL
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Blocks debugger read/write access to all secure CPU
registers and secure memory mapped addresses
Unprotected
0xFFFFFFFF
Unprotected
Protected
0x00000000
Protected
4.6.1.6 ERASEPROTECT
Address offset: 0x030
Erase protection
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW PALL
4418_1315 v1.0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Unprotected
0xFFFFFFFF
Unprotected
Protected
0x00000000
Protected
Blocks NVMC ERASEALL and CTRLAP ERASEALL functionality
42
Application core
4.6.1.7 OTP[n] (n=0..189)
Address offset: 0x108 + (n × 0x4)
One time programmable memory
Bit number
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 6 5 4 3 2 1 0
ID
B B B B B B B B B B B B B B B B A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW1 LOWER
Value ID
Value
Description
Lower half word
Note: Can only be written to a non 0xFFFF value
once.
B
RW1 UPPER
Upper half word
Note: Can only be written to a non 0xFFFF value
once.
4.6.1.8 KEYSLOT.CONFIG[n].DEST (n=0..127)
Address offset: 0x400 + (n × 0x8)
Destination address where content of the key value registers (KEYSLOT.KEYn.VALUE[0-3]) will be pushed by
KMU. Note that this address MUST match that of a peripherals APB mapped write-only key registers, else
the KMU can push this key value into an address range which the CPU can potentially read!
Writing/reading this register requires the KMU SELECTKEYSLOT register to be set to n+1.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW DEST
Value ID
Value
Description
Secure APB destination address
4.6.1.9 KEYSLOT.CONFIG[n].PERM (n=0..127)
Address offset: 0x404 + (n × 0x8)
Define permissions for the key slot. Bits 0-15 and 16-31 can only be written when equal to 0xFFFF.
Writing/reading this register requires the KMU SELECTKEYSLOT register to be set to n+1.
Bit number
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 6 5 4 3 2 1 0
ID
D
Reset 0xFFFFFFFF
ID
Access
Field
A
RW WRITE
B
C
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
Write permission for key slot
Disabled
0
Disable write to the key value registers
Enabled
1
Enable write to the key value registers
RW READ
Read permission for key slot
Disabled
0
Disable read from key value registers
Enabled
1
Enable read from key value registers
RW PUSH
4418_1315 v1.0
C B A
Push permission for key slot
43
Application core
Bit number
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 6 5 4 3 2 1 0
ID
D
Reset 0xFFFFFFFF
ID
Access
Field
C B A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
Disabled
0
Disable pushing of key value registers over secure APB, but
can be read if field READ is Enabled
Enabled
1
Enable pushing of key value registers over secure APB.
Register KEYSLOT.CONFIGn.DEST must contain a valid
destination address!
D
RW STATE
Revocation state for the key slot
Note that it is not possible to undo a key revocation by
writing the value '1' to this field
Revoked
0
Key value registers can no longer be read or pushed
Active
1
Key value registers are readable (if enabled) and can be
pushed (if enabled)
4.6.1.10 KEYSLOT.KEY[n].VALUE[o] (n=0..127) (o=0..3)
Address offset: 0x800 + (n × 0x10) + (o × 0x4)
Define bits [31+o*32:0+o*32] of value assigned to KMU key slot.
Writing/reading this register requires the KMU SELECTKEYSLOT register to be set to n+1.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW VALUE
Value ID
Value
Description
Define bits [31+o*32:0+o*32] of value assigned to KMU key
slot
4.7 EasyDMA
EasyDMA is a module implemented by some peripherals to gain direct access to Data RAM.
EasyDMA is an AHB bus master similar to CPU and is connected to the AHB multilayer interconnect for
direct access to Data RAM. EasyDMA is not able to access flash.
A peripheral can implement multiple EasyDMA instances to provide dedicated channels. For example,
for reading and writing of data between the peripheral and RAM. This concept is illustrated in EasyDMA
example on page 45.
4418_1315 v1.0
44
Application core
AHB multilayer
RAM
Peripheral
READER
AHB
RAM
EasyDMA
WRITER
RAM
AHB
Peripheral
core
EasyDMA
Figure 5: EasyDMA example
An EasyDMA channel is implemented in the following way, but some variations may occur:
READERBUFFER_SIZE 5
WRITERBUFFER_SIZE 6
uint8_t readerBuffer[READERBUFFER_SIZE]
__at__ 0x20000000;
uint8_t writerBuffer[WRITERBUFFER_SIZE]
__at__ 0x20000005;
// Configuring the READER channel
MYPERIPHERAL->READER.MAXCNT = READERBUFFER_SIZE;
MYPERIPHERAL->READER.PTR = &readerBuffer;
// Configure the WRITER channel
MYPERIPHERAL->WRITER.MAXCNT = WRITEERBUFFER_SIZE;
MYPERIPHERAL->WRITER.PTR = &writerBuffer;
This example shows a peripheral called MYPERIPHERAL that implements two EasyDMA channels - one for
reading called READER, and one for writing called WRITER. When the peripheral is started, it is assumed
that the peripheral will:
• Read 5 bytes from the readerBuffer located in RAM at address 0x20000000.
• Process the data.
• Write no more than 6 bytes back to the writerBuffer located in RAM at address 0x20000005.
The memory layout of these buffers is illustrated in EasyDMA memory layout on page 45.
0x20000000
readerBuffer[0]
readerBuffer[1]
readerBuffer[2]
readerBuffer[3]
0x20000004
readerBuffer[4]
writerBuffer[0]
writerBuffer[1]
writerBuffer[2]
0x20000008
writerBuffer[3]
writerBuffer[4]
writerBuffer[5]
Figure 6: EasyDMA memory layout
4418_1315 v1.0
45
Application core
The WRITER.MAXCNT register should not be specified larger than the actual size of the buffer
(writerBuffer). Otherwise, the channel would overflow the writerBuffer.
Once an EasyDMA transfer is completed, the AMOUNT register can be read by the CPU to see how many
bytes were transferred. For example, CPU can read MYPERIPHERAL->WRITER.AMOUNT register to see how
many bytes WRITER wrote to RAM.
Note that the PTR register of a READER or WRITER must point to a valid memory region before use. The
reset value of a PTR register is not guaranteed to point to valid memory. See Memory on page 20 for
more information about the different memory regions and EasyDMA connectivity.
4.7.1 EasyDMA error handling
Some errors may occur during DMA handling.
If READER.PTR or WRITER.PTR is not pointing to a valid memory region, an EasyDMA transfer may result
in a HardFault or RAM corruption. See Memory on page 20 for more information about the different
memory regions.
If several AHB bus masters try to access the same AHB slave at the same time, AHB bus congestion might
occur. An EasyDMA channel is an AHB master. Depending on the peripheral, the peripheral may either stall
and wait for access to be granted, or lose data.
4.7.2 EasyDMA array list
EasyDMA is able to operate in Array List mode.
The Array List mode is implemented in channels where the LIST register is available.
The array list does not provide a mechanism to explicitly specify where the next item in the list is located.
Instead, it assumes that the list is organized as a linear array where items are located one after the other
in RAM.
The EasyDMA Array List can be implemented by using the data structure ArrayList_type as illustrated in
the code example below using a READER EasyDMA channel as an example:
#define BUFFER_SIZE
4
typedef struct ArrayList
{
uint8_t buffer[BUFFER_SIZE];
} ArrayList_type;
ArrayList_type ReaderList[3]
__at__ 0x20000000;
MYPERIPHERAL->READER.MAXCNT = BUFFER_SIZE;
MYPERIPHERAL->READER.PTR = &ReaderList;
MYPERIPHERAL->READER.LIST = MYPERIPHERAL_READER_LIST_ArrayList;
The data structure only includes a buffer with size equal to the size of READER.MAXCNT register. EasyDMA
uses the READER.MAXCNT register to determine when the buffer is full.
4418_1315 v1.0
46
Application core
READER.PTR = &ReaderList
0x20000000 : ReaderList[0]
buffer[0]
buffer[1]
buffer[2]
buffer[3]
0x20000004 : ReaderList[1]
buffer[0]
buffer[1]
buffer[2]
buffer[3]
0x20000008 : ReaderList[2]
buffer[0]
buffer[1]
buffer[2]
buffer[3]
Figure 7: EasyDMA array list
4.8 AHB multilayer interconnect
On the AHB multilayer interconnect, the application CPU and all EasyDMA instances are AHB bus masters
while RAM, cache and peripherals are AHB slaves. External MCU subsystems can be seen both as master
and slave on the AHB multilayer interconnect.
Multiple AHB masters can access slave resources within the AHB multilayer interconnect as illustrated in
Memory on page 20. Access rights to each of the AHB slaves are resolved using the natural priority of
the different bus masters in the system.
4418_1315 v1.0
47
5
Power and clock management
5.1 Functional description
The power and clock management system automatically ensures maximum power efficiency.
The core of the power and clock management is the power management unit (PMU) illustrated in the
image below.
VDD
Power
management
IC
(PMIC)
Application core
PMU
Clock
sources
LTE
modem
Memory
Peripherals
The PMU automatically tracks the power and clock resources required by the different components in the
system. It then starts/stops and chooses operation modes in supply regulators and clock sources, without
user interaction, to achieve the lowest power consumption possible.
5.1.1 Power management
The power management unit (PMU) handles two system-wide power modes - System ON and System OFF.
Internal blocks of the device are automatically powered by the PMU as they are required by the
application.
5.1.1.1 System ON mode
System ON is the power mode entered after a power-on reset.
While in System ON, the system can reside in one of two sub modes:
• Low power
• Constant latency
The low power mode is default after power-on reset.
In low power mode, whenever no application or wireless activity takes place, function blocks like the
application CPU, LTE modem and all peripherals are in IDLE state. That particular state is referred to as
System ON IDLE. In this state, all function blocks retain their state and configuration, so they are ready to
become active once configured by the CPU.
4418_1315 v1.0
48
Power and clock management
If any application or modem activity occurs, the system leaves the System ON IDLE state. Once a
given activity in a function block is completed, the system automatically returns to IDLE, retaining its
configuration.
As long as the system resides in low power mode, the PMU ensures that the appropriate regulators and
clock sources are started or stopped based on the needs of the function blocks active at any given time.
This automatic power management can be overridden by switching to constant latency mode. In this
mode, the CPU wakeup latency and the PPI task response are constant and kept at a minimum. This
is secured by keeping a set of base resources that are always enabled. The advantage of having a
constant and predictable latency will be at the cost of having significantly increased power consumption
compared to the low power mode. The constant latency mode is enabled by triggering the CONSTLAT task
(TASKS_CONSTLAT on page 60).
While the system is in constant latency mode, the low power mode can be enabled by triggering LOWPWR
task (TASKS_LOWPWR on page 60).
To reduce power consumption while in System ON IDLE, RAM blocks can be turned off in System ON mode
while enabling the retention of these RAM blocks in RAM[n].POWER registers in VMC. RAM[n].POWER are
retained registers, see Reset behavior on page 55. Note that these registers are usually overwritten by
the startup code provided with the nRF application examples.
5.1.1.2 System OFF mode
System OFF is the deepest power saving mode the system can enter.
In this mode, the core system functionality is powered down and ongoing tasks terminated, and only the
reset and the wakeup functions are available and responsive.
The device is put into System OFF mode using the REGULATORS register interface. When in System OFF
mode, one of the following signals/actions will wake up the device:
1. DETECT signal, generated by the GPIO peripheral
2. RESET
3. start of debug session
When the device wakes up from System OFF mode, a system reset is performed.
One or more RAM blocks can be retained in System OFF mode depending on the settings in the
RAM[n].POWER registers in VMC. RAM[n].POWER are retained registers, see Reset behavior on page
55. Note that these registers are usually overwritten by the startup code provided with the nRF
application examples.
Before entering System OFF mode, the user must make sure that all on-going EasyDMA transactions have
completed. This can be accomplished by making sure that EasyDMA enabled peripherals have stopped and
END events from them received. The LTE modem also needs to be stopped, by issuing a command through
the modem API, before entering System OFF mode. Once the command is issued, one should wait for the
modem to respond that it actually has stopped, as there may be a delay until modem is disconnected from
the network.
5.1.1.2.1 Emulated System OFF mode
If the device is in debug interface mode, System OFF will be emulated to secure that all required resources
needed for debugging are available during System OFF.
See Overview on page 371 chapter for more information. Required resources needed for debugging
include the following key components: Overview on page 371, CLOCK — Clock control on page 65,
POWER — Power control on page 59, NVMC — Non-volatile memory controller on page 28, CPU on
page 19, flash, and RAM. Since the CPU is kept on in emulated System OFF mode, it is required to add an
infinite loop directly after entering System OFF, to prevent the CPU from executing code that normally
should not be executed.
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Power and clock management
5.1.2 Power supply
The device has a single main power supply VDD, and the internal components are powered by integrated
voltage regulators. The PMU manages these regulators automatically, no voltage regulator control needs
to be included in application firmware.
5.1.2.1 General purpose I/O supply
The input/output (I/O) drivers of P0.00 - P0.31 pins are supplied independently of VDD through
VDD_GPIO. This enables easy match to signal voltage levels in the printed circuit board design.
nRF9160
GPIO
External supply
...
VDD_GPIO
P0.00
P0.01
P0.30
P0.31
Figure 8: GPIO supply input (VDD_GPIO)
The I/Os are supplied via VDD_GPIO pin as shown in figure above. VDD_GPIO pin supports voltage levels
within range given in table Recommended operating conditions on page 390
5.1.3 Power supply monitoring
Power monitor solutions are available in the device, in order to survey the VDD (battery voltage).
5.1.3.1 Power supply supervisor
The power supply supervisor enables monitoring of the connected power supply.
Two functionalities are implemented:
• Power-on reset (POR): Generates a reset when the supply is applied to the device, and ensures that the
device starts up in a known state
• Brownout reset (BOR): Generates a reset when the supply drops below the minimum voltage required
for safe operations
Two BOR levels are used:
• VBOROFF, used in System OFF
• VBORON, used in System ON
The power supply supervisor is illustrated in the image below.
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Power and clock management
VDD
C
Power-on reset
R
VBOR
Brownout reset
Figure 9: Power supply supervisor
5.1.3.2 Battery monitoring on VDD
A battery voltage (VDD) monitoring capability is provided via a modem API
Note: For details regarding the modem API, please refer to nRF Connect SDK document and nRF91
AT Commands, Command Reference Guide document.
5.1.3.3 Electrical specification
5.1.3.3.1 Device startup times
Symbol
Description
Min.
Typ.
Max.
Units
tPOR
Time in power-on reset after VDD has reached VPOR (if
..
..
..
ms
..
..
..
ENABLE is tied to VDD) or after ENABLE input has been set
to to logic high.
tPINR
The maximum time taken to pull up the nRESET pin and
release reset after power-on reset. Dependent on the pin
capacitive load (C)2: t=5RC, R=13 kΩ.
tPINR,500nF
C=500 nF
..
..
..
ms
tPINR,10uF
C=10 µF
..
..
..
ms
tR2ON
Time from reset to ON (CPU execute)
tOFF2ON
Time from OFF to CPU execute
36
µs
tWFE2CPU
Time from WFE to CPU execute
22
µs
tWFI2CPU
Time from WFI to CPU execute
33
tEVTSET,CL1
Time from HW event to PPI event in constant latency System
µs
µs
..
..
..
µs
..
..
..
µs
ON mode
tEVTSET,CL0
Time from HW event to PPI event in low power System ON
mode
2
To decrease the maximum time a device could be held in reset, a strong external pull-up resistor can
be used.
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Power and clock management
5.1.3.3.2 Power supply supervisor
Symbol
Description
Min.
VBOR
Brownout reset voltage threshold.
VPOR
Voltage threshold at which the device enters power-on reset
Typ.
Max.
2.00
Units
V
2.15
V
(POR) when VDD is ramping up.
5.1.4 Clock management
The clock control system can source the system clocks from a range of high and low frequency oscillators,
and distribute them to modules based upon a module's individual requirements. Clock generation and
distribution is handled automatically by PMU to optimize current consumption.
Listed here are the available clock signal sources:
•
•
•
•
64 MHz oscillator (HFINT)
64 MHz high accuracy oscillator (HFXO)
32.768 kHz RC oscillator (LFRC)
32.768 kHz high accuracy oscillator (LFXO)
The clock and oscillator resources are configured and controlled via the CLOCK peripheral as illustrated
below.
Clock and oscillator control unit
PCLK1M
HFXO
oscillator
(high accuracy)
HFCLK
clock control
PCLK16M
PCLK32M
HCLK
HFINT
oscillator
(low accuracy)
LFRC
RC
oscillator
LFXO
oscillator
LFCLKSTART
LFCLK
clock control
CLOCK
LFCLKSTOP
LFCLKSTARTED
LFCLKSRC
HFCLKCTRL
HFCLKSTOP
HFCLKSTART
Figure 10: Clock and oscillator setup
5.1.4.1 HFCLK clock controller
The HFCLK clock controller provides several clocks in the system.
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52
HFCLKSTARTED
Power and clock management
These are as follows:
•
•
•
•
HCLK: 64 MHz CPU clock
PCLK1M: 1 MHz peripheral clock
PCLK16M: 16 MHz peripheral clock
PCLK32M: 32 MHz peripheral clock
The HFCLK controller uses the following high frequency clock (HFCLK) sources:
• 64 MHz oscillator (HFINT)
• 64 MHz high accuracy oscillator (HFXO)
For illustration, see Clock and oscillator setup on page 52.
The HFCLK controller will automatically provide the clock(s) requested by the system. If the system does
not request any clocks from the HFCLK controller, the controller will switch off all its clock sources and
enter a power saving mode.
The HFINT source will be used when HFCLK is requested and HFXO has not been started.
The HFXO is started by triggering the HFCLKSTART task and stopped using the HFCLKSTOP task. A
HFCLKSTARTED event will be generated when the HFXO has started and its frequency is stable.
5.1.4.2 LFCLK clock controller
The system supports several low frequency clock sources.
As illustrated in Clock and oscillator setup on page 52, the system supports the following low
frequency clock sources:
• LFRC: 32.768 kHz RC oscillator
• LFXO: 32.768 kHz high accuracy oscillator
The LFCLK clock controller and all LFCLK clock sources are always switched off when in System OFF mode.
The LFCLK clock is started by first selecting the preferred clock source in the LFCLKSRC on page 72
register and then triggering the LFCLKSTART task. LFXO is highly recommended as the LFCLK clock source,
since the LFRC has a large frequency variation.
Note: The LTE modem requires using LFXO as the LFCLK source.
Switching between LFCLK clock sources can be done without stopping the LFCLK clock. A LFCLK clock
source which is running prior to triggering the LFCLKSTART task will continue to run until the selected clock
source has been available. After that the clock sources will be switched. Switching between clock sources
will never introduce a glitch but it will stretch a clock pulse by 0.5 to 1.0 clock cycle (i.e. will delay rising
edge by 0.5 to 1.0 clock cycle).
Note: If the watchdog timer (WDT) is running, the default LFCLK clock source (LFRC - see LFCLKSRC
on page 72) is started automatically (LFCLKSTART task doesn't have to be triggered).
A LFCLKSTARTED event will be generated when the selected LFCLK clock source has started.
Note: When selecting LFXO as clock source for the first time, LFRC quality is provided until LFXO is
stable.
A LFCLKSTOP task will stop global requesting of the LFCLK clock. However, if any system component
(e.g. WDT, modem) requires the LFCLK, the clock won't be stopped. The LFCLKSTOP task should only be
triggered after the STATE field in the LFCLKSTAT register indicates a LFCLK running-state.
5.1.4.2.1 32.768 kHz RC oscillator (LFRC)
The default source of the low frequency clock (LFCLK) is the 32.768 kHz RC oscillator (LFRC).
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Power and clock management
The LFRC frequency will be affected by variation in temperature.
5.1.4.3 Electrical specification
5.1.4.3.1 64 MHz internal oscillator (HFINT)
Symbol
Description
fNOM_HFINT
Nominal output frequency
Min.
Typ.
64
fTOL_HFINT
Frequency tolerance
+-1
tSTART_HFINT
Startup time
3.2
Max.
Units
MHz
+-5
%
µs
5.1.4.3.2 64 MHz high accuracy oscillator (HFXO)
Symbol
Description
fNOM_HFXO
Nominal output frequency
Min.
Typ.
64
Max.
Units
MHz
fTOL_HFXO
Frequency tolerance
+-1
ppm
tSTART_HFXO
Startup time
TBA
ms
5.1.4.3.3 32.768 kHz high accuracy oscillator (LFXO)
Symbol
Description
Min.
Typ.
Max.
Units
fNOM_LFXO
Frequency
32.768
kHz
fTOL_LFXO
Frequency tolerance
+-20
ppm
tSTART_LFXO
Startup time
200
ms
5.1.4.3.4 32.768 kHz RC oscillator (LFRC)
Symbol
Description
fNOM_LFRC
Nominal frequency
Min.
Typ.
32.768
Max.
Units
kHz
fTOL_LFRC
Frequency tolerance
30
%
tSTART_LFRC
Startup time
600
µs
5.1.5 Reset
There are multiple reset sources that may trigger a reset of the system. After a reset the CPU can query
the RESETREAS (reset reason register) to find out which source generated the reset.
5.1.5.1 Power-on reset
The power-on reset generator initializes the system at power-on. The system is held in reset state until the
supply has reached the minimum operating voltage and the internal voltage regulators have started.
5.1.5.2 Pin reset
A pin reset is generated when the physical reset pin (nRESET) on the device is pulled low.
To ensure that reset is issued correctly, the reset pin should be held low for time given in .
nRESET pin has an always-on internal pull-up resistor connected to VDD. The value of the pull-up resistor is
given in .
5.1.5.3 Wakeup from System OFF mode reset
The device is reset when it wakes up from System OFF mode.
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Power and clock management
The Debug access port is not reset following a wake up from System OFF mode if the device is in debug
interface mode, see Overview on page 371 chapter for more information.
5.1.5.4 Soft reset
A soft reset is generated when the SYSRESETREQ bit of the application interrupt and reset control register
(AIRCR register) in the ARM® core is set.
5.1.5.5 Watchdog reset
A watchdog reset is generated when the watchdog timer (WDT) times out.
See WDT — Watchdog timer on page 357 chapter for more information.
5.1.5.6 Brownout reset
The brownout reset generator puts the system in reset state if the supply voltage drops below the
brownout reset threshold.
5.1.5.7 Retained registers
A retained register is a register that will retain its value in System OFF mode, and through a reset
depending on reset source. See individual peripheral chapters for information of which registers are
retained for the different peripherals.
5.1.5.8 Reset behavior
Reset behavior depends on the reset source.
The reset behavior is summarized in the table below.
Reset source
Reset target
CPU
Modem
Debug3
SWJ-DP
Not retained Retained
RAM
4
RAM
WDT
x
x
Soft reset
x
x
Wakeup from System OFF
x
x
x6
x
x
Watchdog reset 7
x
x
x
x
x
Pin reset
x
x
x
x
x
Brownout reset
x
x
x
x
x
x
x
Power-on reset
x
x
x
x
x
x
x
CPU lockup
5
RESETREAS
4
mode reset
x
x
Table 16: Reset behavior for the main components
Note: The RAM is never reset but its content may be corrupted after reset in the cases given in the
table above.
3
4
5
6
7
All debug components excluding SWJ-DP. See Overview on page 371 chapter for more information
about the different debug components in the system.
RAM can be configured to be retained using registers in VMC — Volatile memory controller on page
26
Reset from CPU lockup is disabled if the device is in debug interface mode. CPU lockup is not possible
in System OFF.
The debug components will not be reset if the device is in debug interface mode.
Watchdog reset is not available in System OFF.
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Power and clock management
Reset source
Reset target
Regular peripheral
GPIO, SPU
NVMC
registers
CPU lockup
5
Soft reset
x
x
x
x
x
x
Wakeup from System OFF mode reset x
7
NVMC
REGULATORS, POWER.GPREGRET
WAITSTATENUM IFCREADDELAY
OSCILLATORS
x
Watchdog reset
x
x
x
x
Pin reset
x
x
x
x
Brownout reset
x
x
x
x
x
x
Power-on reset
x
x
x
x
x
x
Table 17: Reset behavior for the retained registers
5.1.5.9 Electrical specification
5.1.5.9.1 Pin reset
Symbol
Description
Min.
tHOLDRESET
Hold time for reset pin when doing a pin reset
5
RPULL-UP
Value of the internal pull-up resistor
Typ.
Max.
Units
µs
kΩ
5.2 Current consumption
As the system is being constantly tuned by the PMU described in Functional description on page 48,
estimating the current consumption of an application can be challenging if the designer is not able to
perform measurements directly on the hardware. To facilitate the estimation process, a set of current
consumption scenarios are provided to show the typical current drawn from the VDD supply.
Each scenario specifies a set of operations and conditions applying to the given scenario. Current
consumption scenarios, common conditions on page 56 shows a set of common conditions used
in all scenarios, unless otherwise is stated in the description of a given scenario. Current consumption
scenarios, common conditions on page 57 describes the conditions used for the modem current
consumption specifications. All scenarios are listed in Electrical specification on page 57
Condition
Value
Supply
3.7 V
Temperature
25 °C
CPU
WFI (wait for interrupt)/WFE (wait for event) sleep
Peripherals
All idle
Clock
Not running
RAM
No retention
Cache enabled
Yes
Table 18: Current consumption scenarios, common conditions
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Power and clock management
Condition
Cat-M1 HD FDD mode
Ideal channel, no errors in DL/UL communication
Network response times at minimum
UICC current consumption excluded
Output power at antenna port, single-ended 50 Ω
All LTE modem current consumption numbers include application core idle mode consumption
Table 19: Current consumption scenarios, common conditions
5.2.1 Electrical specification
5.2.1.1 Sleep
Symbol
Description
IMCUOFF0
MCU off, modem off, no RAM retention, wake on GPIO and
Min.
Typ.
Max.
Units
1.4
µA
reset
IMCUON0
MCU on IDLE, modem off, RTC off
1.8
µA
IMCUON1
MCU on IDLE, modem off, RTC on
2.35
µA
5.2.1.2 Application CPU active current consumption
Symbol
Description
ICPU0_FLASH
CPU running CoreMark @64 MHz from flash, clock = HFXO,
Min.
Typ.
Max.
Units
2.88
mA
ICOREMARK_PER_MA_FLASH
CoreMark per mA, executing from flash, CoreMark=243
84
CoreMark/
ICPU0_RAM
2.32
mA
101
CoreMark/
cache enabled
mA
CPU running CoreMark @64 MHz from RAM, clock = HFXO,
cache enabled
ICOREMARK_PER_MA_RAMCoreMark per mA, executing from RAM, CoreMark=235
mA
5.2.1.3 I2S
Symbol
Description
II2S0
I2S transferring data @ 2 x 16 bit x 16 kHz
Min.
Typ.
Max.
TBA
Units
µA
(CONFIG.MCKFREQ = 32MDIV63, CONFIG.RATIO = 32X)
5.2.1.4 PDM
Symbol
Description
IPDM
PDM receiving and processing data @ 1 Msps
4418_1315 v1.0
Min.
Typ.
TBA
57
Max.
Units
µA
Power and clock management
5.2.1.5 PWM
Symbol
Description
IPWM0
PWM running @ 125 kHz, fixed duty cycle
Min.
Typ.
986.89
Max.
Units
µA
IPWM1
PWM running @ 16 MHz, fixed duty cycle
1160.77
µA
5.2.1.6 SAADC
Symbol
Description
Min.
ISAADC_HFXO
SAADC sampling @ 16 ksps, with high accuracy clock HFXO,
Typ.
Max.
Units
1300
µA
302.34
µA
acquisition time = 20 µs
ISAADC_HFINT
SAADC sampling @ 16 ksps, with low accuracy clock HFINT,
acquisition time = 20 µs
5.2.1.7 TIMER
Symbol
Description
ITIMER0
TIMER running @ 1 MHz
Min.
Typ.
772.87
Max.
Units
µA
ITIMER1
TIMER running @ 16 MHz
867.34
µA
5.2.1.8 SPIM
Symbol
Description
Min.
Typ.
Max.
Units
ISPIM0
SPIM transferring data @ 2 Mbps, Clock = HFINT
1.2
mA
ISPIM1
SPIM transferring data @ 2 Mbps, Clock = HFXO
1.9
mA
ISPIM2
SPIM transferring data @ 8 Mbps, Clock = HFINT
1.5
mA
ISPIM3
SPIM transferring data @ 8 Mbps, Clock = HFXO
2.2
mA
5.2.1.9 SPIS
Symbol
Description
ISPIS0
SPIS transferring data @ 2 Mbps
Min.
Typ.
Max.
TBA
Units
µA
5.2.1.10 TWIM
Symbol
Description
ITWIM0
TWIM running @ 100 kbps
Min.
Typ.
Max.
TBA
Units
µA
5.2.1.11 TWIS
Symbol
Description
Min.
Typ.
Max.
Units
ITWIS,RUN0
TWIS transferring data @ 100 kbps
TBA
µA
ITWIS1,RUN1
TWIS transferring data @ 400 kbps,
TBA
µA
5.2.1.12 UARTE
Symbol
Description
IUARTE
UARTE transferring data @ 1200 bps
TBA
µA
IUARTE
UARTE transferring data @ 115200 bps
TBA
µA
4418_1315 v1.0
Min.
58
Typ.
Max.
Units
Power and clock management
5.2.1.13 WDT
Symbol
Description
IWDT
WDT started
Min.
Typ.
Max.
3.95
Units
µA
5.2.1.14 Modem current consumption
Symbol
Description
B13
B20
B3
B4
(typ.)
(typ.)
(typ.)
(typ.)
Units
4
4
4
4
µA
Modem sleep current consumption
IPSM
PSM floor current
Radio resource control (RRC) mode
IEDRX
eDRX average current, 81.92 s
19
19
19
19
µA
IIDRX
Idle DRX average current, 2.56 s
199
199
199
199
µA
IRMC_0DBM
Uplink 180 kbit/s, Pout 0 dBm, RMC settings as per 3GPP TS 36.521-1 Annex A.2
45
45
45
45
mA
IRMC_10DBM
Uplink 180 kbit/s, Pout 10 dBm, RMC settings as per 3GPP TS 36.521-1 Annex A.2
50
50
55
55
mA
IRMC_23DBM
Uplink 180 kbit/s, Pout 23 dBm, RMC settings as per 3GPP TS 36.521-1 Annex A.2
105
110
140
140
mA
Modem active current consumption
ITX_0DBM
TX subframe, Pout 0 dBm
60
60
65
65
mA
ITX_10DBM
TX subframe, Pout 10 dBm
80
85
95
90
mA
ITX_23DBM
TX subframe, Pout 23 dBm
255
275
380
365
mA
IRX_-90DBM
RX subframe, Pin -90 dBm
45
45
45
45
mA
ITX_TRANSIENT
TX transient
40
45
50
50
mA/µs
Modem peak current consumption
ITX_PEAK
TX subframe, Pout >21 dBm, Ant VSWR3
335
360
455
450
mA
ITX_PEAK
TX subframe, Pout >20 dBm, Ant VSWR3, Vbat 3.5 V, Temp 85 °C
350
380
460
450
mA
ITX_PEAK
TX subframe, Pout >20 dBm, Ant VSWR3, Vbat 3.0 V, Temp 85 °C
410
445
535
525
mA
5.2.1.15 GPS current consumption
Symbol
Description
IGPS_CONTINUOUS
Continuous tracking, typical peak current without power
Min.
Typ.
Max.
Units
47
mA
IGPS_CONTINUOUS_PSM Continuous tracking, power saving mode
12
mA
IGPS_SINGLE
1.3
mA
saving mode
Single shot, one fix every 2 minutes
5.3 Register description
5.3.1 POWER — Power control
The POWER module provides an interface to tasks, events, interrupt and reset related configuration
settings of the power management unit.
Note: Registers INTEN on page 63, INTENSET on page 63, and INTENCLR on page 64 are
the same registers (at the same address) as corresponding registers in CLOCK — Clock control on
page 65.
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5.3.1.1 Registers
Base address Peripheral
Instance
0x50005000
POWER : S
0x40005000
POWER
POWER : NS
Secure mapping
DMA security
Description
US
NA
Power control
Configuration
Table 20: Instances
Register
Offset
Security
Description
TASKS_CONSTLAT
0x78
Enable constant latency mode.
TASKS_LOWPWR
0x7C
Enable low power mode (variable latency)
SUBSCRIBE_CONSTLAT
0xF8
Subscribe configuration for task CONSTLAT
SUBSCRIBE_LOWPWR
0xFC
Subscribe configuration for task LOWPWR
EVENTS_POFWARN
0x108
Power failure warning
EVENTS_SLEEPENTER
0x114
CPU entered WFI/WFE sleep
EVENTS_SLEEPEXIT
0x118
CPU exited WFI/WFE sleep
PUBLISH_POFWARN
0x188
Publish configuration for event POFWARN
PUBLISH_SLEEPENTER
0x194
Publish configuration for event SLEEPENTER
PUBLISH_SLEEPEXIT
0x198
Publish configuration for event SLEEPEXIT
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
RESETREAS
0x400
Reset reason
POWERSTATUS
0x440
Modem domain power status
GPREGRET[0]
0x51C
General purpose retention register
GPREGRET[1]
0x520
General purpose retention register
Table 21: Register overview
5.3.1.1.1 TASKS_CONSTLAT
Address offset: 0x78
Enable constant latency mode.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_CONSTLAT
Enable constant latency mode.
Trigger task
5.3.1.1.2 TASKS_LOWPWR
Address offset: 0x7C
Enable low power mode (variable latency)
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_LOWPWR
Enable low power mode (variable latency)
Trigger task
5.3.1.1.3 SUBSCRIBE_CONSTLAT
Address offset: 0xF8
Subscribe configuration for task CONSTLAT
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task CONSTLAT will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.1.1.4 SUBSCRIBE_LOWPWR
Address offset: 0xFC
Subscribe configuration for task LOWPWR
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task LOWPWR will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.1.1.5 EVENTS_POFWARN
Address offset: 0x108
Power failure warning
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_POFWARN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Power failure warning
NotGenerated
0
Event not generated
Generated
1
Event generated
5.3.1.1.6 EVENTS_SLEEPENTER
Address offset: 0x114
CPU entered WFI/WFE sleep
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_SLEEPENTER
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
CPU entered WFI/WFE sleep
5.3.1.1.7 EVENTS_SLEEPEXIT
Address offset: 0x118
CPU exited WFI/WFE sleep
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_SLEEPEXIT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
CPU exited WFI/WFE sleep
5.3.1.1.8 PUBLISH_POFWARN
Address offset: 0x188
Publish configuration for event POFWARN
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event POFWARN will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
5.3.1.1.9 PUBLISH_SLEEPENTER
Address offset: 0x194
Publish configuration for event SLEEPENTER
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event SLEEPENTER will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
5.3.1.1.10 PUBLISH_SLEEPEXIT
Address offset: 0x198
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Publish configuration for event SLEEPEXIT
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event SLEEPEXIT will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
5.3.1.1.11 INTEN
Address offset: 0x300
Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
D C
Reset 0x00000000
ID
Access
Field
A
RW POFWARN
C
D
A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Enable or disable interrupt for event POFWARN
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
RW SLEEPENTER
Enable or disable interrupt for event SLEEPENTER
RW SLEEPEXIT
Enable or disable interrupt for event SLEEPEXIT
5.3.1.1.12 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
D C
Reset 0x00000000
ID
Access
Field
A
RW POFWARN
C
D
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to enable interrupt for event POFWARN
RW SLEEPENTER
Write '1' to enable interrupt for event SLEEPENTER
RW SLEEPEXIT
4418_1315 v1.0
A
Write '1' to enable interrupt for event SLEEPEXIT
63
Power and clock management
5.3.1.1.13 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
D C
Reset 0x00000000
ID
Access
Field
A
RW POFWARN
C
D
A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event POFWARN
RW SLEEPENTER
Write '1' to disable interrupt for event SLEEPENTER
RW SLEEPEXIT
Write '1' to disable interrupt for event SLEEPEXIT
5.3.1.1.14 RESETREAS
Address offset: 0x400
Reset reason
Unless cleared, the RESETREAS register will be cumulative. A field is cleared by writing '1' to it. If none
of the reset sources are flagged, this indicates that the chip was reset from the on-chip reset generator,
which will indicate a power-on reset or a brownout reset.
Bit number
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 6 5 4 3 2 1 0
ID
G F E
Reset 0x00000000
ID
Access
Field
A
RW RESETPIN
B
C
D
Value ID
Value
Description
NotDetected
0
Not detected
Detected
1
Detected
NotDetected
0
Not detected
Detected
1
Detected
Reset from pin reset detected
RW DOG
Reset from global watchdog detected
RW OFF
Reset due to wakeup from System OFF mode, when wakeup
is triggered by DETECT signal from GPIO
D
NotDetected
0
Not detected
Detected
1
Detected
RW DIF
Reset due to wakeup from System OFF mode, when wakeup
is triggered by entering debug interface mode
E
F
NotDetected
0
Not detected
Detected
1
Detected
RW SREQ
Reset from AIRCR.SYSRESETREQ detected
NotDetected
0
Not detected
Detected
1
Detected
RW LOCKUP
4418_1315 v1.0
C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Reset from CPU lock-up detected
64
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
G F E
Reset 0x00000000
ID
G
Access
Field
D
C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotDetected
0
Not detected
Detected
1
Detected
NotDetected
0
Not detected
Detected
1
Detected
RW CTRLAP
Reset triggered through CTRL-AP
5.3.1.1.15 POWERSTATUS
Address offset: 0x440
Modem domain power status
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
OFF
0
LTE modem domain is powered off
ON
1
LTE modem domain is powered on
LTEMODEM
LTE modem domain status
5.3.1.1.16 GPREGRET[n] (n=0..1)
Address offset: 0x51C + (n × 0x4)
General purpose retention register
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW GPREGRET
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
General purpose retention register
This register is a retained register
5.3.2 CLOCK — Clock control
The CLOCK module provides one of the interfaces to power and clock management configuration settings.
Through CLOCK module it is able to configure the following:
•
•
•
•
•
LFCLK clock source setup
LFCLK and HFCLK status
Tasks and events
Interrupts
Reset
Note: Registers INTEN on page 69, INTENSET on page 70, and INTENCLR on page 70 are
the same registers (at the same address) as corresponding registers in POWER — Power control on
page 59.
4418_1315 v1.0
65
Power and clock management
5.3.2.1 Registers
Base address Peripheral
Instance
0x50005000
CLOCK : S
0x40005000
CLOCK
CLOCK : NS
Secure mapping
DMA security
Description
US
NA
Clock control
Configuration
Table 22: Instances
Register
Offset
Security
Description
TASKS_HFCLKSTART
0x000
Start HFCLK source
TASKS_HFCLKSTOP
0x004
Stop HFCLK source
TASKS_LFCLKSTART
0x008
Start LFCLK source
TASKS_LFCLKSTOP
0x00C
Stop LFCLK source
SUBSCRIBE_HFCLKSTART
0x080
Subscribe configuration for task HFCLKSTART
SUBSCRIBE_HFCLKSTOP
0x084
Subscribe configuration for task HFCLKSTOP
SUBSCRIBE_LFCLKSTART
0x088
Subscribe configuration for task LFCLKSTART
SUBSCRIBE_LFCLKSTOP
0x08C
Subscribe configuration for task LFCLKSTOP
EVENTS_HFCLKSTARTED
0x100
HFCLK oscillator started
EVENTS_LFCLKSTARTED
0x104
LFCLK started
PUBLISH_HFCLKSTARTED
0x180
Publish configuration for event HFCLKSTARTED
PUBLISH_LFCLKSTARTED
0x184
Publish configuration for event LFCLKSTARTED
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
INTPEND
0x30C
Pending interrupts
HFCLKRUN
0x408
Status indicating that HFCLKSTART task has been triggered
HFCLKSTAT
0x40C
The register shows if HFXO has been requested by triggering HFCLKSTART task and
LFCLKRUN
0x414
Status indicating that LFCLKSTART task has been triggered
LFCLKSTAT
0x418
The register shows which LFCLK source has been requested (SRC) when triggering
LFCLKSRCCOPY
0x41C
Copy of LFCLKSRC register, set after LFCLKSTART task has been triggered
LFCLKSRC
0x518
Clock source for the LFCLK. LFCLKSTART task starts starts a clock source selected
if it has been started (STATE)
LFCLKSTART task and if the source has been started (STATE)
with this register.
Table 23: Register overview
5.3.2.1.1 TASKS_HFCLKSTART
Address offset: 0x000
Start HFCLK source
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_HFCLKSTART
Start HFCLK source
Trigger
1
Trigger task
5.3.2.1.2 TASKS_HFCLKSTOP
Address offset: 0x004
Stop HFCLK source
4418_1315 v1.0
66
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_HFCLKSTOP
Stop HFCLK source
Trigger task
5.3.2.1.3 TASKS_LFCLKSTART
Address offset: 0x008
Start LFCLK source
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_LFCLKSTART
Start LFCLK source
Trigger task
5.3.2.1.4 TASKS_LFCLKSTOP
Address offset: 0x00C
Stop LFCLK source
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_LFCLKSTOP
Stop LFCLK source
Trigger task
5.3.2.1.5 SUBSCRIBE_HFCLKSTART
Address offset: 0x080
Subscribe configuration for task HFCLKSTART
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task HFCLKSTART will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.2.1.6 SUBSCRIBE_HFCLKSTOP
Address offset: 0x084
Subscribe configuration for task HFCLKSTOP
4418_1315 v1.0
67
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task HFCLKSTOP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.2.1.7 SUBSCRIBE_LFCLKSTART
Address offset: 0x088
Subscribe configuration for task LFCLKSTART
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task LFCLKSTART will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.2.1.8 SUBSCRIBE_LFCLKSTOP
Address offset: 0x08C
Subscribe configuration for task LFCLKSTOP
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task LFCLKSTOP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
5.3.2.1.9 EVENTS_HFCLKSTARTED
Address offset: 0x100
HFCLK oscillator started
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_HFCLKSTARTED
4418_1315 v1.0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
HFCLK oscillator started
68
Power and clock management
5.3.2.1.10 EVENTS_LFCLKSTARTED
Address offset: 0x104
LFCLK started
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_LFCLKSTARTED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
LFCLK started
5.3.2.1.11 PUBLISH_HFCLKSTARTED
Address offset: 0x180
Publish configuration for event HFCLKSTARTED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event HFCLKSTARTED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
5.3.2.1.12 PUBLISH_LFCLKSTARTED
Address offset: 0x184
Publish configuration for event LFCLKSTARTED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event LFCLKSTARTED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
5.3.2.1.13 INTEN
Address offset: 0x300
Enable or disable interrupt
4418_1315 v1.0
69
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
RW HFCLKSTARTED
B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Enable or disable interrupt for event HFCLKSTARTED
RW LFCLKSTARTED
Enable or disable interrupt for event LFCLKSTARTED
5.3.2.1.14 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
RW HFCLKSTARTED
B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to enable interrupt for event HFCLKSTARTED
RW LFCLKSTARTED
Write '1' to enable interrupt for event LFCLKSTARTED
5.3.2.1.15 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
RW HFCLKSTARTED
B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event HFCLKSTARTED
RW LFCLKSTARTED
Write '1' to disable interrupt for event LFCLKSTARTED
5.3.2.1.16 INTPEND
Address offset: 0x30C
Pending interrupts
4418_1315 v1.0
70
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
R
B
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotPending
0
Read: Not pending
Pending
1
Read: Pending
NotPending
0
Read: Not pending
Pending
1
Read: Pending
HFCLKSTARTED
Read pending status of interrupt for event HFCLKSTARTED
LFCLKSTARTED
Read pending status of interrupt for event LFCLKSTARTED
5.3.2.1.17 HFCLKRUN
Address offset: 0x408
Status indicating that HFCLKSTART task has been triggered
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotTriggered
0
Task not triggered
Triggered
1
Task triggered
STATUS
HFCLKSTART task triggered or not
5.3.2.1.18 HFCLKSTAT
Address offset: 0x40C
The register shows if HFXO has been requested by triggering HFCLKSTART task and if it has been started
(STATE)
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
HFXO
1
Description
SRC
Active clock source
HFXO - 64 MHz clock derived from external 32 MHz crystal
oscillator
B
R
STATE
HFCLK state
NotRunning
0
Running
1
HFXO has not been started or HFCLKSTOP task has been
triggered
HFXO has been started (HFCLKSTARTED event has been
generated)
5.3.2.1.19 LFCLKRUN
Address offset: 0x414
Status indicating that LFCLKSTART task has been triggered
4418_1315 v1.0
A
71
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotTriggered
0
Task not triggered
Triggered
1
Task triggered
STATUS
LFCLKSTART task triggered or not
5.3.2.1.20 LFCLKSTAT
Address offset: 0x418
The register shows which LFCLK source has been requested (SRC) when triggering LFCLKSTART task and if
the source has been started (STATE)
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
R
B
R
A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
RFU
0
Reserved for future use
LFRC
1
32.768 kHz RC oscillator
LFXO
2
32.768 kHz crystal oscillator
NotRunning
0
Running
1
SRC
Active clock source
STATE
LFCLK state
Requested LFCLK source has not been started or LFCLKSTOP
task has been triggered
Requested LFCLK source has been started (LFCLKSTARTED
event has been generated)
5.3.2.1.21 LFCLKSRCCOPY
Address offset: 0x41C
Copy of LFCLKSRC register, set after LFCLKSTART task has been triggered
Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000001
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
SRC
Clock source
RFU
0
Reserved for future use
LFRC
1
32.768 kHz RC oscillator
LFXO
2
32.768 kHz crystal oscillator
5.3.2.1.22 LFCLKSRC
Address offset: 0x518
Clock source for the LFCLK. LFCLKSTART task starts starts a clock source selected with this register.
4418_1315 v1.0
72
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000001
ID
Access
Field
A
RW SRC
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
RFU
0
Reserved for future use (equals selecting LFRC)
LFRC
1
32.768 kHz RC oscillator
LFXO
2
32.768 kHz crystal oscillator
Clock source
5.3.3 REGULATORS — Voltage regulators control
The REGULATORS module provides an interface to certain configuration settings of on-chip voltage
regulators.
5.3.3.1 Registers
Base address Peripheral
Instance
Secure mapping
DMA security
Description
US
NA
Regulator configuration
Configuration
REGULATORS :
0x50004000
0x40004000
REGULATORS
S
REGULATORS :
NS
Table 24: Instances
Register
Offset
SYSTEMOFF
0x500
Security
Description
System OFF register
DCDCEN
0x578
Enable DC/DC mode of the main voltage regulator.
Table 25: Register overview
5.3.3.1.1 SYSTEMOFF
Address offset: 0x500
System OFF register
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
SYSTEMOFF
Enable System OFF mode
Enable
1
Enable System OFF mode
5.3.3.1.2 DCDCEN
Address offset: 0x578
Enable DC/DC mode of the main voltage regulator.
Note: DCDCEN must be set to 1 (enabled) before the LTE modem is started.
4418_1315 v1.0
73
Power and clock management
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW DCDCEN
4418_1315 v1.0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
DC/DC mode is disabled
Enabled
1
DC/DC mode is enabled
Enable DC/DC converter
74
6
Peripherals
6.1 CRYPTOCELL — ARM TrustZone CryptoCell 310
ARM® TrustZone® CryptoCell 310 (CRYPTOCELL) is a security subsystem which provides root of trust (RoT)
and cryptographic services for a device.
Flash
Data RAM
CRYPTOCELL library
CRYPTOCELL
workspace
ARM Cortex CPU
AHB multilayer
SRAM
TRNG
Always-on
domain
Control
interface
Engine control logic
SRAM
Public key
accelerator
engine
DMA
Data routing
AES
HASH
AHB-APB bridge
ChaCha
CRYPTOCELL
APB
Figure 11: Block diagram for CRYPTOCELL
The following cryptographic features are provided:
• True random number generator (TRNG) compliant with NIST 800-90B, AIS-31, and FIPS 140-2
• Pseudorandom number generator (PRNG) using underlying AES engine compliant with NIST 800-90A
• RSA public key cryptography
• Up to 2048-bit key size
• PKCS#1 v2.1/v1.5
• Optional CRT support
• Elliptic curve cryptography (ECC)
• NIST FIPS 186-4 recommended curves using pseudorandom parameters, up to 521 bits:
• Prime field: P-192, P-224, P-256, P-384, P-521
• SEC 2 recommended curves using pseudorandom parameters, up to 521 bits:
• Prime field: secp160r1, secp192r1, secp224r1, secp256r1, secp384r1, secp521r1
• Koblitz curves using fixed parameters, up to 256 bits:
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• Prime field: secp160k1, secp192k1, secp224k1, secp256k1
• Edwards/Montgomery curves:
• Ed25519, Curve25519
• ECDH/ECDSA support
• Secure remote password protocol (SRP)
• Up to 3072-bit operations
• Hashing functions
• SHA-1, SHA-2 up to 256 bits
• Keyed-hash message authentication code (HMAC)
• AES symmetric encryption
• General purpose AES engine (encrypt/decrypt, sign/verify)
• 128-bit key size
• Supported encryption modes: ECB, CBC, CMAC/CBC-MAC, CTR, CCM/CCM* (CCM* is a minor
variation of CCM)
• ChaCha20/Poly1305 symmetric encryption
• Supported key size: 128 and 256 bits
• Authenticated encryption with associated data (AEAD) mode
6.1.1 Usage
The CRYPTOCELL state is controlled via a register interface. The cryptographic functions of CRYPTOCELL are
accessible by using a software library provided in the device SDK, not directly via a register interface.
To enable CRYPTOCELL, use register ENABLE on page 78.
WARNING: Keeping the CRYPTOCELL subsystem enabled will prevent the device from reaching the
System ON, All Idle state.
6.1.2 Always-on (AO) power domain
The CRYPTOCELL subsystem has an internal always-on (AO) power domain for retaining device secrets
when CRYPTOCELL is disabled.
The following information is retained by the AO power domain:
• 4 bits indicating the configured CRYPTOCELL lifecycle state (LCS)
• 1 bit indicating if the hard-coded RTL key, KPRTL (see RTL key on page 77), is available for use
• 128-bit device root key, KDR (see Device root key on page 77)
A reset from any reset source will erase the content in the AO power domain.
6.1.3 Lifecycle state (LCS)
Lifecycle refers to multiple states a device goes through during its lifetime. Two valid lifecycle states are
offered for the device - debug and secure.
The CRYPTOCELL subsystem lifecycle state (LCS) is controlled through register HOST_IOT_LCS on page
81. A valid LCS is configured by writing either value Debug or Secure into the LCS field of this
register. A correctly configured LCS can be validated by reading back the read-only field LCS_IS_VALID from
the abovementioned register. The LCS_IS_VALID field value will change from Invalid to Valid once a
valid LCS value has been written.
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LCS field value
LCS_IS_VALID field value
Secure
Invalid
Secure
Valid
Description
Default reset value indicating that LCS has not been configured.
LCS set to secure mode, and LCS is valid. Registers HOST_IOT_KDR[0..3] can only be written once per reset cycle.
Any additional writes will be ignored.
Debug
Valid
LCS set to debug mode, and LCS is valid. Registers HOST_IOT_KDR[0..3] can be written multiple times.
Table 26: Lifecycle states
6.1.4 Cryptographic key selection
The CRYPTOCELL subsystem can be instructed to operate on different cryptographic keys.
Through register HOST_CRYPTOKEY_SEL on page 79, the following key types can be selected for
cryptographic operations:
• RTL key KPRTL
• Device root key KDR
• Session key
KPRTL and KDR are configured as part of the CRYPTOCELL initialization process, while session keys are
provided by the application through the software library API.
6.1.4.1 RTL key
The ARM® TrustZone® CryptoCell 310 contains one hard-coded RTL key referred to as KPRTL. This key is set
to the same value for all devices with the same part code in the hardware design and cannot be changed.
The KPRTL key can be requested for use in cryptographic operations by the CRYPTOCELL, without revealing
the key value itself. Access to use of KPRTL in cryptographic operations can be disabled until next reset by
writing to register HOST_IOT_KPRTL_LOCK on page 80. If a locked KPRTL key is requested for use, a zero
vector key will be routed to the AES engine instead.
6.1.4.2 Device root key
The device root key KDR is a 128-bit AES key programmed into the CRYPTOCELL subsystem using firmware.
It is retained in the AO power domain until the next reset.
Once configured, it is possible to perform cryptographic operations using the the CRYPTOCELL subsystem
where KDR is selected as key input without having access to the key value itself. The KDR key value must
be written to registers HOST_IOT_KDR[0..3]. These 4 registers are write-only if LCS is set to debug mode,
and write-once if LCS is set to secure mode. The KDR key value is successfully retained when the read-back
value of register HOST_IOT_KDR0 on page 80 changes to 1.
6.1.5 Direct memory access (DMA)
The CRYPTOCELL subsystem implements direct memory access (DMA) for accessing memory without CPU
intervention.
Any data stored in memory type(s) not accessible by the DMA engine must be copied to SRAM before it
can be processed by the CRYPTOCELL subsystem. Maximum DMA transaction size is limited to 216-1 bytes.
6.1.6 Standards
ARM® TrustZone® CryptoCell 310 (CRYPTOCELL) supports a number of cryptography standards.
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Algorithm family
Identification code
Document title
TRNG
NIST SP 800-90B
Recommendation for the Entropy Sources Used for Random Bit Generation
AIS-31
A proposal for: Functionality classes and evaluation methodology for physical random number generators
FIPS 140-2
Security Requirements for Cryptographic Modules
PRNG
NIST SP 800-90A
Recommendation for Random Number Generation Using Deterministic Random Bit Generators
Stream cipher
Chacha
ChaCha, a variant of Salsa20, Daniel J. Bernstein, January 28th 2008
MAC
Poly1305
The Poly1305-AES message-authentication code, Daniel J. Bernstein
Cryptography in NaCl, Daniel J. Bernstein
Key agreement
SRP
The Secure Remote Password Protocol, Thomas Wu, November 11th 1997
AES
FIPS-197
Advanced Encryption Standard (AES)
NIST SP 800-38A
Recommendation for Block Cipher Modes of Operation - Methods and Techniques
NIST SP 800-38B
Recommendation for Block Cipher Modes of Operation: The CMAC Mode for Authentication
NIST SP 800-38C
Recommendation for Block Cipher Modes of Operation: The CCM Mode for Authentication and
Confidentiality
ISO/IEC 9797-1
AES CBC-MAC per ISO/IEC 9797-1 MAC algorithm 1
IEEE 802.15.4-2011
IEEE Standard for Local and metropolitan area networks - Part 15.4: Low-Rate Wireless Personal Area
Networks (LR-WPANs), Annex B.4: Specification of generic CCM* mode of operation
Hash
FIPS 180-3
Secure Hash Standard (SHA1, SHA-224, SHA-256)
RFC2104
HMAC: Keyed-Hashing for Message Authentication
RSA
PKCS#1
Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications v1.5/2.1
Diffie-Hellman
ANSI X9.42
Public Key Cryptography for the Financial Services Industry: Agreement of Symmetric Keys Using Discrete
Logarithm Cryptography
ECC
PKCS#3
Diffie-Hellman Key-Agreement Standard
ANSI X9.63
Public Key Cryptography for the Financial Services Industry - Key Agreement and Key Transport Using
Elliptic Curve Cryptography
IEEE 1363
Standard Specifications for Public-Key Cryptography
ANSI X9.62
Public Key Cryptography For The Financial Services Industry: The Elliptic Curve Digital Signature Algorithm
(ECDSA)
Edwards-curve, Ed25519: high-speed high-security signatures, Daniel J. Bernstein, Niels Duif, Tanja Lange,
Ed25519
Peter Schwabe, and Bo-Yin Yang
Curve25519
Montgomery curve, Curve25519: new Diffie-Hellman speed records, Daniel J. Bernstein
FIPS 186-4
Digital Signature Standard (DSS)
SEC 2
Recommended Elliptic Curve Domain Parameters, Certicom Research
NIST SP 800-56A rev. 2
Recommendation for Pair-Wise Key Establishment Schemes Using Discrete Logarithm Cryptography
Table 27: CRYPTOCELL cryptography standards
6.1.7 Registers
Base address Peripheral
Instance
Secure mapping
DMA security
Description
0x50840000
CRYPTOCELL
S
NSA
CryptoCell sub-system control
CRYPTOCELL
interface
Table 28: Instances
Register
Offset
ENABLE
0x500
Security
Description
Enable CRYPTOCELL subsystem
Table 29: Register overview
6.1.7.1 ENABLE
Address offset: 0x500
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Enable CRYPTOCELL subsystem
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW ENABLE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
CRYPTOCELL subsystem disabled
Enabled
1
CRYPTOCELL subsystem enabled.
Enable or disable the CRYPTOCELL subsystem
When enabled the CRYPTOCELL subsystem can be initialized
and controlled through the CryptoCell firmware API.
6.1.8 Host interface
This chapter describes host registers used to control the CRYPTOCELL subsystem behavior.
6.1.8.1 HOST_RGF block
The HOST_RGF block contains registers for configuring LCS and device root key KDR, in addition to selecting
which cryptographic key is connected to the AES engine.
6.1.8.1.1 Registers
Base address Peripheral
0x50840000
Instance
Secure mapping
CC_HOST_RGF CC_HOST_RGF S
DMA security
Description
NSA
Host platform interface
Configuration
Table 30: Instances
Register
Offset
HOST_CRYPTOKEY_SEL
0x1A38
Security
Description
AES hardware key select
HOST_IOT_KPRTL_LOCK
0x1A4C
This write-once register is the K_PRTL lock register. When this register is set,
K_PRTL cannot be used and a zeroed key will be used instead. The value of this
register is saved in the CRYPTOCELL AO power domain.
HOST_IOT_KDR0
0x1A50
This register holds bits 31:0 of K_DR. The value of this register is saved in the
CRYPTOCELL AO power domain. Reading from this address returns the K_DR valid
status indicating if K_DR is successfully retained.
HOST_IOT_KDR1
0x1A54
This register holds bits 63:32 of K_DR. The value of this register is saved in the
CRYPTOCELL AO power domain.
HOST_IOT_KDR2
0x1A58
HOST_IOT_KDR3
0x1A5C
This register holds bits 95:64 of K_DR. The value of this register is saved in the
CRYPTOCELL AO power domain.
This register holds bits 127:96 of K_DR. The value of this register is saved in the
CRYPTOCELL AO power domain.
HOST_IOT_LCS
0x1A60
Controls lifecycle state (LCS) for CRYPTOCELL subsystem
Table 31: Register overview
6.1.8.1.1.1 HOST_CRYPTOKEY_SEL
Address offset: 0x1A38
AES hardware key select
If the HOST_IOT_KPRTL_LOCK register is set, and the HOST_CRYPTOKEY_SEL register set to 1, then the HW
key that is connected to the AES engine is zero
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Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000000
ID
Access
Field
A
RW HOST_CRYPTOKEY_SEL
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Select the source of the HW key that is used by the AES
engine
K_DR
0
Use device root key K_DR from CRYPTOCELL AO power
K_PRTL
1
Use hard-coded RTL key K_PRTL
Session
2
Use provided session key
domain
6.1.8.1.1.2 HOST_IOT_KPRTL_LOCK
Address offset: 0x1A4C
This write-once register is the K_PRTL lock register. When this register is set, K_PRTL cannot be used and a
zeroed key will be used instead. The value of this register is saved in the CRYPTOCELL AO power domain.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW HOST_IOT_KPRTL_LOCK
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
This register is the K_PRTL lock register. When this register
is set, K_PRTL cannot be used and a zeroed key will be
used instead. The value of this register is saved in the
CRYPTOCELL AO power domain.
Disabled
0
Enabled
1
K_PRTL can be selected for use from register
HOST_CRYPTOKEY_SEL
K_PRTL has been locked until next power-on reset (POR).
If K_PRTL is selected anyway, a zeroed key will be used
instead.
6.1.8.1.1.3 HOST_IOT_KDR0
Address offset: 0x1A50
This register holds bits 31:0 of K_DR. The value of this register is saved in the CRYPTOCELL AO power
domain. Reading from this address returns the K_DR valid status indicating if K_DR is successfully retained.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW HOST_IOT_KDR0
Value ID
Value
Description
Write: K_DR bits 31:0.
Read: 0x00000000 when 128-bit K_DR key value is not yet
retained in the CRYPTOCELL AO power domain.
Read: 0x00000001 when 128-bit K_DR key value is
successfully retained in the CRYPTOCELL AO power domain.
6.1.8.1.1.4 HOST_IOT_KDR1
Address offset: 0x1A54
This register holds bits 63:32 of K_DR. The value of this register is saved in the CRYPTOCELL AO power
domain.
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
W
Value ID
Value
Description
HOST_IOT_KDR1
K_DR bits 63:32
6.1.8.1.1.5 HOST_IOT_KDR2
Address offset: 0x1A58
This register holds bits 95:64 of K_DR. The value of this register is saved in the CRYPTOCELL AO power
domain.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
HOST_IOT_KDR2
K_DR bits 95:64
6.1.8.1.1.6 HOST_IOT_KDR3
Address offset: 0x1A5C
This register holds bits 127:96 of K_DR. The value of this register is saved in the CRYPTOCELL AO power
domain.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
HOST_IOT_KDR3
K_DR bits 127:96
6.1.8.1.1.7 HOST_IOT_LCS
Address offset: 0x1A60
Controls lifecycle state (LCS) for CRYPTOCELL subsystem
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000002
ID
Access
Field
A
RW LCS
B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Value ID
Value
Description
Debug
0
CC310 operates in debug mode
Secure
2
CC310 operates in secure mode
Lifecycle state value. This field is write-once per reset.
RW LCS_IS_VALID
Read-only field. Indicates if CRYPTOCELL LCS has been
successfully configured since last reset.
Invalid
0
Valid
1
Valid LCS not yet retained in the CRYPTOCELL AO power
domain
Valid LCS successfully retained in the CRYPTOCELL AO power
domain
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6.2 DPPI - Distributed programmable peripheral
interconnect
The distributed programmable peripheral interconnect (DPPI) enables peripherals to interact
autonomously with each other by using tasks and events, without any intervention from the CPU. DPPI
allows precise synchronization between peripherals when real-time application constraints exist, and
eliminates the need for CPU involvement to implement behavior which can be predefined using the DPPI.
Note: Read Peripheral interface on page 14 to get familiarized with tasks, events, publish/
subscribe, interrupts and other concepts.
The DPPI has the following features:
• Peripheral tasks can subscribe to channels
• Peripheral events can be published on channels
• Publish/subscribe pattern enabling multiple connection options that include the following:
•
•
•
•
One-to-one
One-to-many
Many-to-one
Many-to-many
The DPPI consists of several PPIBus modules, which are connected to a fixed number of DPPI channels and
a DPPI configuration (DPPIC).
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tasks[0:M-1]
events[0:N-1]
PPIBus
Channel X-1
PeripheralCore
Channel 2
Channel 0
Peripheral A
Channel 1
Peripherals
ppiBusProducer [0:X-1]
ppiBusConsumer[0:X-1]
Peripheral B
CHENSET / CHENCLR
DPPI
configuration
tasks[0:J-1]
events[0:I-1]
PeripheralCore
ppiBusProducer [0:X-1]
PPIBus
ppiBusConsumer[0:X-1]
Figure 12: DPPI overview
6.2.1 Subscribing to and publishing on channels
The PPIBus can route peripheral events onto the channels (publishing), or route events from the channels
into peripheral tasks (subscribing).
All peripherals include:
• One subscribe register per task
• One publish register per event
Publish and subscribe registers use a channel index field to determine the channel to which the event is
published or tasks subscribed. In addition, there is an enable bit for the subscribe and publish registers
that needs to be enabled before the subscription or publishing takes effect.
One event can trigger multiple tasks by subscribing different tasks to the same channel. Similarly, one
task can be triggered by multiple events by publishing different events to the same channel. For advanced
use cases, multiple events and multiple tasks can connect to the same channel forming a many-to-many
connection. If multiple events are published on the same channel at the same time, the events are merged
and only one event is routed through the DPPI.
How peripheral events are routed onto different channels based on publish registers is illustrated in the
figure below.
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Peripherals
event[0]
event[N-1]
PeripheralCore
PPIBus
EN
PUB[0]
EN
PUB[N-1]
ppiBusProducer[X-1]
CHIDX
ppiBusProducer[0]
CHIDX
Figure 13: DPPI events flow
How peripheral tasks are triggered from different channels based on subscribe registers is illustrated in the
figure below.
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ppiBusConsumer[X-1]
ppiBusConsumer[1]
ppiBusConsumer[0]
Peripherals
PPIBus
SUB[0]
SUB[M-1]
CHIDX
CHIDX
EN
task[0]
task[M-1]
EN
PeripheralCore
Figure 14: DPPI tasks flow
6.2.2 DPPI configuration (DPPIC)
Enabling and disabling of channels globally is handled through the DPPI configuration (DPPIC). Connection
(connect/disconnect) between a channel and a peripheral is handled locally by the PPIBus.
There are two ways of enabling and disabling global channels using the DPPI configuration:
• Enable or disable channels individually using registers CHEN, CHENSET, and CHENCLR
• Enable or disable channels in channel groups using the groups' tasks ENABLE and DISABLE. It needs to
be defined which channels belong to which channel groups before these tasks are triggered.
Note: ENABLE tasks are prioritized over DISABLE tasks. When a channel belongs to two or more
groups, for example group m and n, and the tasks CHG[m].EN and CHG[n].DIS occur simultaneously
(m and n can be equal or different), the CHG[m].EN task on that channel is prioritized.
The DPPI configuration tasks (for example CHG[0].EN) can be triggered through DPPI like any other task,
which means they can be linked to a DPPI channel through the subscribe registers.
In order to write to CHG[x], the corresponding CHG[x].EN and CHG[x].DIS subscribe registers must be
disabled. Writes to CHG[x] are ignored if any of the two subscribe registers are enabled.
6.2.3 Connection examples
DPPI offers several connection options. Examples are given for how to create one-to-one and many-tomany connections.
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One-to-one connection
This example shows how to create a one-to-one connection between TIMER compare register and SAADC
start task.
The channel configuration is set up first. TIMER0 will publish its COMPARE0 event on channel 0, and
SAADC will subscribe its START task to events on the same channel. After that, the channel is enabled
through the DPPIC.
NRF_TIMER0->PUBLISH_COMPARE0 = (DPPI_PUB_CHIDX_Ch0) |
NRF_SAADC->SUBSCRIBE_START
(DPPI_PUB_EN_Msk);
= (DPPI_SUB_CHIDX_Ch0) |
(DPPI_SUB_EN_Msk);
NRF_DPPIC->CHENSET = (DPPI_CHENSET_CH0_Set = 1.7
3
mA
V
tRF,15pF
Rise/fall time, standard drive mode, 10-90%, 15 pF load1
6
9
19
ns
tRF,25pF
1
10
13
30
ns
1
Rise/fall time, standard drive mode, 10-90%, 25 pF load
tRF,50pF
18
25
61
ns
tHRF,15pF
1
Rise/Fall time, high drive mode, 10-90%, 15 pF load
2
4
8
ns
tHRF,25pF
Rise/Fall time, high drive mode, 10-90%, 25 pF load1
3
5
11
ns
tHRF,50pF
1
Rise/Fall time, high drive mode, 10-90%, 50 pF load
5
8
19
ns
RPU
Pull-up resistance
11
13
16
kΩ
RPD
Pull-down resistance
11
13
16
kΩ
1
Rise/fall time, standard drive mode, 10-90%, 50 pF load
Rise and fall times based on simulations
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Symbol
Description
CPAD
Pad capacitance
Min.
Typ.
Max.
3
Units
pF
6.5 GPIOTE — GPIO tasks and events
The GPIO tasks and events (GPIOTE) module provides functionality for accessing GPIO pins using tasks and
events. Each GPIOTE channel can be assigned to one pin.
A GPIOTE block enables GPIOs to generate events on pin state change which can be used to carry out tasks
through the PPI system. A GPIO can also be driven to change state on system events using the PPI system.
Taks and events are briefly introduced as part of the Peripheral interface on page 14, whereas GPIO is
described in more detail in GPIO — General purpose input/output on page 95.
Low power detection of pin state changes is possible when in System ON or System OFF.
Instance
Number of GPIOTE channels
GPIOTE
8
Table 38: GPIOTE properties
Up to three tasks can be used in each GPIOTE channel for performing write operations to a pin. Two tasks
are fixed (SET and CLR), and one (OUT) is configurable to perform following operations:
• Set
• Clear
• Toggle
An event can be generated in each GPIOTE channel from one of the following input conditions:
• Rising edge
• Falling edge
• Any change
6.5.1 Pin events and tasks
The GPIOTE module has a number of tasks and events that can be configured to operate on individual
GPIO pins.
The tasks (SET[n], CLR[n] and OUT[n]) can be used for writing to individual pins, and the events (IN[n]) can
be generated from changes occurring at the inputs of individual pins.
The SET task will set the pin selected in GPIOTE.CONFIG[n].PSEL to high.
The CLR task will set the pin low.
The effect of the OUT task on the pin is configurable in CONFIG[n].POLARITY , and can either set the pin
high, set it low, or toggle it.
The tasks and events are configured using the CONFIG[n] registers. Every set of SET, CLR and OUT[n] tasks
and IN[n] events has one CONFIG[n] register associated with it.
As long as a SET[n], CLR[n] and OUT[n] task or an IN[n] event is configured to control a pin n, the pin's
output value will only be updated by the GPIOTE module. The pin's output value as specified in the GPIO
will therefore be ignored as long as the pin is controlled by GPIOTE. Attempting to write a pin as a normal
GPIO pin will have no effect. When the GPIOTE is disconnected from a pin, see MODE field in CONFIG[n]
register, the associated pin will get the output and configuration values specified in the GPIO module.
When conflicting tasks are triggered simultaneously (i.e. during the same clock cycle) in one channel, the
precedence of the tasks will be as described in Task priorities on page 106.
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Priority
Task
1
OUT
2
CLR
3
SET
Table 39: Task priorities
When setting the CONFIG[n] registers, MODE=Disabled does not have the same effect as MODE=Task and
POLARITY=None. In the latter case, a CLR or SET task occurring at the exact same time as OUT will end up
with no change on the pin, according to the priorities described in the table above.
When a GPIOTE channel is configured to operate on a pin as a task, the initial value of that pin is
configured in the OUTINIT field of CONFIG[n].
6.5.2 Port event
PORT is an event that can be generated from multiple input pins using the GPIO DETECT signal.
The event will be generated on the rising edge of the DETECT signal. See GPIO — General purpose input/
output on page 95 for more information about the DETECT signal.
Putting the system into System ON IDLE while DETECT is high will not cause DETECT to wake the system
up again. Make sure to clear all DETECT sources before entering sleep. If the LATCH register is used as a
source, if any bit in LATCH is still high after clearing all or part of the register (for instance due to one of the
PINx.DETECT signal still high), a new rising edge will be generated on DETECT, see Pin sense mechanism on
page 97.
Trying to put the system to System OFF while DETECT is high will cause a wakeup from System OFF reset.
This feature is always enabled although the peripheral itself appears to be IDLE, that is, no clocks or
other power intensive infrastructure have to be requested to keep this feature enabled. This feature can
therefore be used to wake up the CPU from a WFI or WFE type sleep in System ON with all peripherals and
the CPU idle, that is, lowest power consumption in System ON mode.
In order to prevent spurious interrupts from the PORT event while configuring the sources, the user
shall first disable interrupts on the PORT event (through INTENCLR.PORT), then configure the sources
(PIN_CNF[n].SENSE), clear any potential event that could have occurred during configuration (write '1' to
EVENTS_PORT), and finally enable interrupts (through INTENSET.PORT).
6.5.3 Tasks and events pin configuration
Each GPIOTE channel is associated with one physical GPIO pin through the CONFIG.PSEL field.
When Event mode is selected in CONFIG.MODE, the pin specified by CONFIG.PSEL will be configured
as an input, overriding the DIR setting in GPIO. Similarly, when Task mode is selected in CONFIG.MODE,
the pin specified by CONFIG.PSEL will be configured as an output overriding the DIR setting and OUT
value in GPIO. When Disabled is selected in CONFIG.MODE, the pin specified by CONFIG.PSEL will use its
configuration from the PIN[n].CNF registers in GPIO. CONFIG.MODE must be disabled in order to be able
to change the value of the PSEL field.
Note: Only one GPIOTE channel can be assigned to one physical pin. Failing to do so may result in
unpredictable behavior.
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6.5.4 Registers
Base address Peripheral
Instance
Secure mapping
DMA security
Description
0x5000D000
GPIOTE
GPIOTE0
S
NA
Secure GPIO tasks and events
0x40031000
GPIOTE
GPIOTE1
NS
NA
Non Secure GPIO tasks and
Configuration
events
Table 40: Instances
Register
Offset
TASKS_OUT[0]
0x000
Security
Description
TASKS_OUT[1]
0x004
TASKS_OUT[2]
0x008
TASKS_OUT[3]
0x00C
TASKS_OUT[4]
0x010
TASKS_OUT[5]
0x014
TASKS_OUT[6]
0x018
TASKS_OUT[7]
0x01C
TASKS_SET[0]
0x030
Task for writing to pin specified in CONFIG[0].PSEL. Action on pin is to set it high.
TASKS_SET[1]
0x034
Task for writing to pin specified in CONFIG[1].PSEL. Action on pin is to set it high.
TASKS_SET[2]
0x038
Task for writing to pin specified in CONFIG[2].PSEL. Action on pin is to set it high.
TASKS_SET[3]
0x03C
Task for writing to pin specified in CONFIG[3].PSEL. Action on pin is to set it high.
TASKS_SET[4]
0x040
Task for writing to pin specified in CONFIG[4].PSEL. Action on pin is to set it high.
TASKS_SET[5]
0x044
Task for writing to pin specified in CONFIG[5].PSEL. Action on pin is to set it high.
TASKS_SET[6]
0x048
Task for writing to pin specified in CONFIG[6].PSEL. Action on pin is to set it high.
TASKS_SET[7]
0x04C
Task for writing to pin specified in CONFIG[7].PSEL. Action on pin is to set it high.
TASKS_CLR[0]
0x060
Task for writing to pin specified in CONFIG[0].PSEL. Action on pin is to set it low.
TASKS_CLR[1]
0x064
Task for writing to pin specified in CONFIG[1].PSEL. Action on pin is to set it low.
TASKS_CLR[2]
0x068
Task for writing to pin specified in CONFIG[2].PSEL. Action on pin is to set it low.
TASKS_CLR[3]
0x06C
Task for writing to pin specified in CONFIG[3].PSEL. Action on pin is to set it low.
TASKS_CLR[4]
0x070
Task for writing to pin specified in CONFIG[4].PSEL. Action on pin is to set it low.
TASKS_CLR[5]
0x074
Task for writing to pin specified in CONFIG[5].PSEL. Action on pin is to set it low.
TASKS_CLR[6]
0x078
Task for writing to pin specified in CONFIG[6].PSEL. Action on pin is to set it low.
TASKS_CLR[7]
0x07C
Task for writing to pin specified in CONFIG[7].PSEL. Action on pin is to set it low.
SUBSCRIBE_OUT[0]
0x080
Subscribe configuration for task OUT[0]
SUBSCRIBE_OUT[1]
0x084
Subscribe configuration for task OUT[1]
SUBSCRIBE_OUT[2]
0x088
Subscribe configuration for task OUT[2]
SUBSCRIBE_OUT[3]
0x08C
Subscribe configuration for task OUT[3]
SUBSCRIBE_OUT[4]
0x090
Subscribe configuration for task OUT[4]
SUBSCRIBE_OUT[5]
0x094
Subscribe configuration for task OUT[5]
SUBSCRIBE_OUT[6]
0x098
Subscribe configuration for task OUT[6]
SUBSCRIBE_OUT[7]
0x09C
Subscribe configuration for task OUT[7]
SUBSCRIBE_SET[0]
0x0B0
Subscribe configuration for task SET[0]
SUBSCRIBE_SET[1]
0x0B4
Subscribe configuration for task SET[1]
SUBSCRIBE_SET[2]
0x0B8
Subscribe configuration for task SET[2]
Task for writing to pin specified in CONFIG[0].PSEL. Action on pin is configured in
CONFIG[0].POLARITY.
Task for writing to pin specified in CONFIG[1].PSEL. Action on pin is configured in
CONFIG[1].POLARITY.
Task for writing to pin specified in CONFIG[2].PSEL. Action on pin is configured in
CONFIG[2].POLARITY.
Task for writing to pin specified in CONFIG[3].PSEL. Action on pin is configured in
CONFIG[3].POLARITY.
Task for writing to pin specified in CONFIG[4].PSEL. Action on pin is configured in
CONFIG[4].POLARITY.
Task for writing to pin specified in CONFIG[5].PSEL. Action on pin is configured in
CONFIG[5].POLARITY.
Task for writing to pin specified in CONFIG[6].PSEL. Action on pin is configured in
CONFIG[6].POLARITY.
Task for writing to pin specified in CONFIG[7].PSEL. Action on pin is configured in
CONFIG[7].POLARITY.
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Register
Offset
Security
Description
SUBSCRIBE_SET[3]
0x0BC
Subscribe configuration for task SET[3]
SUBSCRIBE_SET[4]
0x0C0
Subscribe configuration for task SET[4]
SUBSCRIBE_SET[5]
0x0C4
Subscribe configuration for task SET[5]
SUBSCRIBE_SET[6]
0x0C8
Subscribe configuration for task SET[6]
SUBSCRIBE_SET[7]
0x0CC
Subscribe configuration for task SET[7]
SUBSCRIBE_CLR[0]
0x0E0
Subscribe configuration for task CLR[0]
SUBSCRIBE_CLR[1]
0x0E4
Subscribe configuration for task CLR[1]
SUBSCRIBE_CLR[2]
0x0E8
Subscribe configuration for task CLR[2]
SUBSCRIBE_CLR[3]
0x0EC
Subscribe configuration for task CLR[3]
SUBSCRIBE_CLR[4]
0x0F0
Subscribe configuration for task CLR[4]
SUBSCRIBE_CLR[5]
0x0F4
Subscribe configuration for task CLR[5]
SUBSCRIBE_CLR[6]
0x0F8
Subscribe configuration for task CLR[6]
SUBSCRIBE_CLR[7]
0x0FC
Subscribe configuration for task CLR[7]
EVENTS_IN[0]
0x100
Event generated from pin specified in CONFIG[0].PSEL
EVENTS_IN[1]
0x104
Event generated from pin specified in CONFIG[1].PSEL
EVENTS_IN[2]
0x108
Event generated from pin specified in CONFIG[2].PSEL
EVENTS_IN[3]
0x10C
Event generated from pin specified in CONFIG[3].PSEL
EVENTS_IN[4]
0x110
Event generated from pin specified in CONFIG[4].PSEL
EVENTS_IN[5]
0x114
Event generated from pin specified in CONFIG[5].PSEL
EVENTS_IN[6]
0x118
Event generated from pin specified in CONFIG[6].PSEL
EVENTS_IN[7]
0x11C
Event generated from pin specified in CONFIG[7].PSEL
EVENTS_PORT
0x17C
Event generated from multiple input GPIO pins with SENSE mechanism enabled
PUBLISH_IN[0]
0x180
Publish configuration for event IN[0]
PUBLISH_IN[1]
0x184
Publish configuration for event IN[1]
PUBLISH_IN[2]
0x188
Publish configuration for event IN[2]
PUBLISH_IN[3]
0x18C
Publish configuration for event IN[3]
PUBLISH_IN[4]
0x190
Publish configuration for event IN[4]
PUBLISH_IN[5]
0x194
Publish configuration for event IN[5]
PUBLISH_IN[6]
0x198
Publish configuration for event IN[6]
PUBLISH_IN[7]
0x19C
Publish configuration for event IN[7]
PUBLISH_PORT
0x1FC
Publish configuration for event PORT
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
CONFIG[0]
0x510
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[1]
0x514
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[2]
0x518
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[3]
0x51C
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[4]
0x520
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[5]
0x524
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[6]
0x528
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
CONFIG[7]
0x52C
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
Table 41: Register overview
6.5.4.1 TASKS_OUT[n] (n=0..7)
Address offset: 0x000 + (n × 0x4)
Task for writing to pin specified in CONFIG[n].PSEL. Action on pin is configured in CONFIG[n].POLARITY.
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_OUT
Task for writing to pin specified in CONFIG[n].PSEL. Action
on pin is configured in CONFIG[n].POLARITY.
Trigger
1
Trigger task
6.5.4.2 TASKS_SET[n] (n=0..7)
Address offset: 0x030 + (n × 0x4)
Task for writing to pin specified in CONFIG[n].PSEL. Action on pin is to set it high.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_SET
Task for writing to pin specified in CONFIG[n].PSEL. Action
on pin is to set it high.
Trigger
1
Trigger task
6.5.4.3 TASKS_CLR[n] (n=0..7)
Address offset: 0x060 + (n × 0x4)
Task for writing to pin specified in CONFIG[n].PSEL. Action on pin is to set it low.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_CLR
Task for writing to pin specified in CONFIG[n].PSEL. Action
on pin is to set it low.
Trigger
1
Trigger task
6.5.4.4 SUBSCRIBE_OUT[n] (n=0..7)
Address offset: 0x080 + (n × 0x4)
Subscribe configuration for task OUT[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task OUT[n] will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.5.4.5 SUBSCRIBE_SET[n] (n=0..7)
Address offset: 0x0B0 + (n × 0x4)
Subscribe configuration for task SET[n]
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Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task SET[n] will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.5.4.6 SUBSCRIBE_CLR[n] (n=0..7)
Address offset: 0x0E0 + (n × 0x4)
Subscribe configuration for task CLR[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task CLR[n] will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.5.4.7 EVENTS_IN[n] (n=0..7)
Address offset: 0x100 + (n × 0x4)
Event generated from pin specified in CONFIG[n].PSEL
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_IN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
Event generated from pin specified in CONFIG[n].PSEL
6.5.4.8 EVENTS_PORT
Address offset: 0x17C
Event generated from multiple input GPIO pins with SENSE mechanism enabled
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_PORT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Event generated from multiple input GPIO pins with SENSE
mechanism enabled
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NotGenerated
0
Event not generated
Generated
1
Event generated
110
Peripherals
6.5.4.9 PUBLISH_IN[n] (n=0..7)
Address offset: 0x180 + (n × 0x4)
Publish configuration for event IN[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event IN[n] will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.5.4.10 PUBLISH_PORT
Address offset: 0x1FC
Publish configuration for event PORT
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event PORT will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.5.4.11 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
I
Reset 0x00000000
ID
Access
Field
A-H
RW IN[i] (i=0..7)
I
H G F E D C B A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to enable interrupt for event IN[i]
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW PORT
Write '1' to enable interrupt for event PORT
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.5.4.12 INTENCLR
Address offset: 0x308
Disable interrupt
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Bit number
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 6 5 4 3 2 1 0
ID
I
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A-H
RW IN[i] (i=0..7)
I
H G F E D C B A
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event IN[i]
RW PORT
Write '1' to disable interrupt for event PORT
6.5.4.13 CONFIG[n] (n=0..7)
Address offset: 0x510 + (n × 0x4)
Configuration for OUT[n], SET[n] and CLR[n] tasks and IN[n] event
Bit number
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 6 5 4 3 2 1 0
ID
E
Reset 0x00000000
ID
Access
Field
A
RW MODE
D D
B B B B B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Mode
Disabled
0
Event
1
Disabled. Pin specified by PSEL will not be acquired by the
GPIOTE module.
Event mode
The pin specified by PSEL will be configured as an input and
the IN[n] event will be generated if operation specified in
POLARITY occurs on the pin.
Task
3
Task mode
The GPIO specified by PSEL will be configured as an output
and triggering the SET[n], CLR[n] or OUT[n] task will
perform the operation specified by POLARITY on the pin.
When enabled as a task the GPIOTE module will acquire the
pin and the pin can no longer be written as a regular output
pin from the GPIO module.
B
RW PSEL
D
RW POLARITY
[0..31]
GPIO number associated with SET[n], CLR[n] and OUT[n]
tasks and IN[n] event
When In task mode: Operation to be performed on output
when OUT[n] task is triggered. When In event mode:
Operation on input that shall trigger IN[n] event.
None
0
Task mode: No effect on pin from OUT[n] task. Event mode:
no IN[n] event generated on pin activity.
LoToHi
1
HiToLo
2
Task mode: Set pin from OUT[n] task. Event mode: Generate
IN[n] event when rising edge on pin.
Task mode: Clear pin from OUT[n] task. Event mode:
Generate IN[n] event when falling edge on pin.
Toggle
3
Task mode: Toggle pin from OUT[n]. Event mode: Generate
IN[n] when any change on pin.
E
RW OUTINIT
When in task mode: Initial value of the output when the
GPIOTE channel is configured. When in event mode: No
effect.
Low
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0
Task mode: Initial value of pin before task triggering is low
112
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
E
Reset 0x00000000
ID
Access
Field
D D
B B B B B
A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
High
1
Task mode: Initial value of pin before task triggering is high
6.5.5 Electrical specification
6.6 IPC — Interprocessor communication
The interprocessor communication (IPC) peripheral is used to send and receive events between MCUs in
the system.
IPC channel M
NVIC
IPC channel 2
Cortex-M
IPC channel 1
System-bus
IPC channel 0
MCU subsystem 0
IRQ
eventOut[0..N]
IPC0
eventIn[0..N]
MCU subsystem 1
System-bus
Cortex-M
NVIC
IRQ
eventOut[0..K]
IPC1
eventIn[0..K]
Figure 18: IPC block diagram
Functional description
IPC block diagram on page 113 illustrates the interprocessor communication (IPC) peripheral. In a multiMCU system, each MCU has one dedicated IPC peripheral. The IPC peripheral can be used to send and
receive events to and from other IPC peripherals. An instance of the IPC peripheral can have multiple
SEND tasks and RECEIVE events. A single SEND task can be configured to signal an event on one or more
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TASK_SEND[0]
TASK_SEND[N]
IPC channel X
IPC channel 0
IPC channels, and a RECEIVE event can be configured to listen on one or more IPC channels. The IPC
channels that are triggered in a SEND task can be configured through the SEND_CNF registers, and the IPC
channels that trigger a RECEIVE event are configured through the RECEIVE_CNF registers. The figure below
illustrates how the SEND_CNF and RECEIVE_CNF registers work. Both the SEND task and the RECEIVE event
can be connected to all IPC channels.
eventOut0
eventOut N
EVENTS_RECEIVE[0]
eventIn1
EVENTS_RECEIVE[N]
eventIn N
Figure 19: IPC registers SEND_CNF and RECEIVE_CNF
A SEND task can be viewed as broadcasting events onto one or more IPC channels, and a RECEIVE event
can be seen as subscribing to a subset of IPC channels. It is possible for multiple IPCs to trigger events onto
the same channel at the same time. When two or more events on the same channel occur within tIPC, the
events may be merged into a single event seen from the IPC receiver. One of the events can therefore be
lost. To prevent this, the user must ensure that events on the same IPC channel do not occur within tIPC of
each other. When implementing firmware data structures, such as queues or mailboxes, this can be done
by using one channel for acknowledgements.
An IPC event often does not contain any data itself, it is used to signal other MCUs that something has
occurred. Data can be shared through shared memory, for example in the form of a software implemented
mailbox, or command/event queues. It is up to software to assign a logical functionality to an IPC channel.
For instance, one IPC channel can be used to signal that a command is ready to be executed, and any
processor in the system can subscribe to that particular channel and decode/execute the command.
General purpose memory
The GPMEM registers can be used freely to store information. These registers are accessed like any other
of the IPC peripheral's registers.
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6.6.1 IPC and PPI connections
The IPC SEND tasks and RECEIVE events can be connected through PPI channels. This makes it possible to
relay events from peripherals in one MCU to another, without CPU involvement.
Figure below illustrates a timer COMPARE event that is relayed from one MCU to IPC using PPI, then back
into a timer CAPTURE event in another MCU.
MCU 0
PPI channel 0
MCU 1
PPI channel 0
IPC channel 0
PUBLISH_COMPARE[0]
TASKS_CAPTURE[0]
TIMER
TIMER
IPC
SUBSCRIBE_SEND[0]
IPC
PUBLISH_RECEIVE[0]
Figure 20: Example of PPI and IPC connections
6.6.2 Registers
Base address Peripheral
Instance
0x5002A000
IPC : S
0x4002A000
IPC
IPC : NS
Secure mapping
US
DMA security
Description
Configuration
Interprocessor
NA
communication
Table 42: Instances
Register
Offset
Security
Description
TASKS_SEND[n]
0x000
Trigger events on IPC channel enabled in SEND_CNF[n]
SUBSCRIBE_SEND[n]
0x080
Subscribe configuration for task SEND[n]
EVENTS_RECEIVE[n]
0x100
Event received on one or more of the enabled IPC channels in RECEIVE_CNF[n]
PUBLISH_RECEIVE[n]
0x180
Publish configuration for event RECEIVE[n]
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
INTPEND
0x30C
Pending interrupts
SEND_CNF[n]
0x510
Send event configuration for TASKS_SEND[n]
RECEIVE_CNF[n]
0x590
Receive event configuration for EVENTS_RECEIVE[n]
GPMEM[0]
0x610
General purpose memory
GPMEM[1]
0x614
General purpose memory
GPMEM[2]
0x618
General purpose memory
GPMEM[3]
0x61C
General purpose memory
Table 43: Register overview
6.6.2.1 TASKS_SEND[n] (n=0..7)
Address offset: 0x000 + (n × 0x4)
Trigger events on IPC channel enabled in SEND_CNF[n]
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_SEND
Trigger events on IPC channel enabled in SEND_CNF[n]
Trigger task
6.6.2.2 SUBSCRIBE_SEND[n] (n=0..7)
Address offset: 0x080 + (n × 0x4)
Subscribe configuration for task SEND[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task SEND[n] will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.6.2.3 EVENTS_RECEIVE[n] (n=0..7)
Address offset: 0x100 + (n × 0x4)
Event received on one or more of the enabled IPC channels in RECEIVE_CNF[n]
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_RECEIVE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Event received on one or more of the enabled IPC channels
in RECEIVE_CNF[n]
NotGenerated
0
Event not generated
Generated
1
Event generated
6.6.2.4 PUBLISH_RECEIVE[n] (n=0..7)
Address offset: 0x180 + (n × 0x4)
Publish configuration for event RECEIVE[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event RECEIVE[n] will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.6.2.5 INTEN
Address offset: 0x300
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Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A-H
RW RECEIVE[i] (i=0..7)
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Enable or disable interrupt for event RECEIVE[i]
Disabled
0
Disable
Enabled
1
Enable
6.6.2.6 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A-H
RW RECEIVE[i] (i=0..7)
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to enable interrupt for event RECEIVE[i]
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.6.2.7 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A-H
RW RECEIVE[i] (i=0..7)
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event RECEIVE[i]
6.6.2.8 INTPEND
Address offset: 0x30C
Pending interrupts
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A-H
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotPending
0
Read: Not pending
Pending
1
Read: Pending
RECEIVE[i] (i=0..7)
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6.6.2.9 SEND_CNF[n] (n=0..7)
Address offset: 0x510 + (n × 0x4)
Send event configuration for TASKS_SEND[n]
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A-H
RW CHEN[i] (i=0..7)
Value ID
Value
Description
Disable
0
Disable broadcast
Enable
1
Enable broadcast
Enable broadcasting on IPC channel i
6.6.2.10 RECEIVE_CNF[n] (n=0..7)
Address offset: 0x590 + (n × 0x4)
Receive event configuration for EVENTS_RECEIVE[n]
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A-H
RW CHEN[i] (i=0..7)
Value ID
Value
Description
Disable
0
Disable events
Enable
1
Enable events
Enable subscription to IPC channel i
6.6.2.11 GPMEM[n] (n=0..3)
Address offset: 0x610 + (n × 0x4)
General purpose memory
Retained only in System ON mode
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW GPMEM
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
General purpose memory
6.6.3 Electrical specification
6.6.3.1 IPC Electrical Specification
Symbol
Description
Min.
Typ.
Max.
Units
tIPC
Minimum IPC event spacing before events are merged
..
..
..
µs
6.7 I2S — Inter-IC sound interface
The I2S (Inter-IC Sound) module, supports the original two-channel I2S format, and left or right-aligned
formats. It implements EasyDMA for sample transfer directly to and from RAM without CPU intervention.
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The I2S peripheral has the following main features:
•
•
•
•
•
•
Master and Slave mode
Simultaneous bi-directional (TX and RX) audio streaming
Original I2S and left- or right-aligned format
8, 16 and 24-bit sample width
Low-jitter Master Clock generator
Various sample rates
PSEL.MCK
PSEL.LRCK
PSEL.SCK
PSEL.SDIN PSEL.SDOUT
I2S
CONFIG.MCKEN
Master clock
generator
MCK
CONFIG.MCKFREQ
CONFIG.RATIO
Div
CONFIG.FORMAT
Div
CONFIG.MODE
Serial tranceiever
TXD.PTR
RXD.PTR
RXTXD.MAXCNT
EasyDMA
SDOUT
SDIN
SCK
LRCK
CONFIG.ALIGN
RAM
Figure 21: I2S master
6.7.1 Mode
The I2S protocol specification defines two modes of operation, Master and Slave.
The I2S mode decides which of the two sides (Master or Slave) shall provide the clock signals LRCK and
SCK, and these signals are always supplied by the Master to the Slave.
6.7.2 Transmitting and receiving
The I2S module supports both transmission (TX) and reception (RX) of serial data. In both cases the serial
data is shifted synchronously to the clock signals SCK and LRCK.
TX data is written to the SDOUT pin on the falling edge of SCK, and RX data is read from the SDIN pin on
the rising edge of SCK. The most significant bit (MSB) is always transmitted first.
Note: When starting a transmission in master mode, two frames (two left-and-right sample pairs)
of value zero will be transmitted after triggering the START task, prior to the RXTXD.MAXCNT
samples specified by the TXD.PTR pointer.
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TX and RX are available in both Master and Slave modes and can be enabled/disabled independently in
the CONFIG.TXEN on page 134 and CONFIG.RXEN on page 133.
Transmission and/or reception is started by triggering the START task. When started and transmission
is enabled (in CONFIG.TXEN on page 134), the TXPTRUPD event will be generated for every
RXTXD.MAXCNT on page 137 number of transmitted data words (containing one or more samples).
Similarly, when started and reception is enabled (in CONFIG.RXEN on page 133), the RXPTRUPD event
will be generated for every RXTXD.MAXCNT on page 137 received data words.
RXTXD.MAXCNT
Left 0
Right 0
Left 1
RIght 1
Left 2
Right 2
Left 3
A
A
A
A
C
C
C
Right 3
C
Left 4
E
B
B
B
B
D
D
D
D
F
RXPTRUPD
TXPTRUPD
RXPTRUPD
RXPTRUPD
TXPTRUPD
RXD.PTR = H
TXD.PTR = G
RXD.PTR = F
TXD.PTR = E
TXD.PTR = C
RXD.PTR = D
START
TXD.PTR = A
RXD.PTR = B
CPU
TXPTRUPD
LRCK
SCK
SDIN
SDOUT
RXTXD.MAXCNT
Figure 22: Transmitting and receiving. CONFIG.FORMAT = Aligned,
CONFIG.SWIDTH = 8Bit, CONFIG.CHANNELS = Stereo, RXTXD.MAXCNT = 1.
6.7.3 Left right clock (LRCK)
The Left Right Clock (LRCK), often referred to as "word clock", "sample clock" or "word select" in I2S
context, is the clock defining the frames in the serial bit streams sent and received on SDOUT and SDIN,
respectively.
In I2S mode, each frame contains one left and right sample pair, with the left sample being transferred
during the low half period of LRCK followed by the right sample being transferred during the high period of
LRCK.
In Aligned mode, each frame contains one left and right sample pair, with the left sample being
transferred during the high half period of LRCK followed by the right sample being transferred during the
low period of LRCK.
Consequently, the LRCK frequency is equivalent to the audio sample rate.
When operating in Master mode, the LRCK is generated from the MCK, and the frequency of LRCK is then
given as:
LRCK = MCK / CONFIG.RATIO
LRCK always toggles around the falling edge of the serial clock SCK.
6.7.4 Serial clock (SCK)
The serial clock (SCK), often referred to as the serial bit clock, pulses once for each data bit being
transferred on the serial data lines SDIN and SDOUT.
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When operating in Master mode the SCK is generated from the MCK, and the frequency of SCK is then
given as:
SCK = 2 * LRCK * CONFIG.SWIDTH
The falling edge of the SCK falls on the toggling edge of LRCK.
When operating in Slave mode SCK is provided by the external I2S master.
6.7.5 Master clock (MCK)
The master clock (MCK) is the clock from which LRCK and SCK are derived when operating in Master mode.
The MCK is generated by an internal MCK generator. This generator always needs to be enabled when in
Master mode, but the generator can also be enabled when in Slave mode. Enabling the generator when
in slave mode can be useful in the case where the external Master is not able to generate its own master
clock.
The MCK generator is enabled/disabled in the register CONFIG.MCKEN on page 134, and the generator
is started or stopped by the START or STOP tasks.
In Master mode the LRCK and the SCK frequencies are closely related, as both are derived from MCK and
set indirectly through CONFIG.RATIO on page 135 and CONFIG.SWIDTH on page 135.
When configuring these registers, the user is responsible for fulfilling the following requirements:
1. SCK frequency can never exceed the MCK frequency, which can be formulated as:
CONFIG.RATIO >= 2 * CONFIG.SWIDTH
2. The MCK/LRCK ratio shall be a multiple of 2 * CONFIG.SWIDTH, which can be formulated as:
Integer = (CONFIG.RATIO / (2 * CONFIG.SWIDTH))
The MCK signal can be routed to an output pin (specified in PSEL.MCK) to supply external I2S devices that
require the MCK to be supplied from the outside.
When operating in Slave mode, the I2S module does not use the MCK and the MCK generator does not
need to be enabled.
RATIO =
MCK
LRCK
MCK
LRCK
SWIDTH
SCK
Figure 23: Relation between RATIO, MCK and LRCK.
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Desired LRCK CONFIG.SWIDTH
CONFIG.RATIO CONFIG.MCKFREQ
MCK [Hz]
[Hz]
LRCK [Hz]
LRCK error
[%]
16000
16Bit
32X
32MDIV63
507936.5
15873.0
-0.8
16000
16Bit
64X
32MDIV31
1032258.1
16129.0
0.8
16000
16Bit
256X
32MDIV8
4000000.0
15625.0
-2.3
32000
16Bit
32X
32MDIV31
1032258.1
32258.1
0.8
32000
16Bit
64X
32MDIV16
2000000.0
31250.0
-2.3
44100
16Bit
32X
32MDIV23
1391304.3
43478.3
-1.4
44100
16Bit
64X
32MDIV11
2909090.9
45454.5
3.1
Table 44: Configuration examples
6.7.6 Width, alignment and format
The CONFIG.SWIDTH register primarily defines the sample width of the data written to memory. In master
mode, it then also sets the amount of bits per frame. In Slave mode it controls padding/trimming if
required. Left, right, transmitted, and received samples always have the same width. The CONFIG.FORMAT
register specifies the position of the data frames with respect to the LRCK edges in both Master and Slave
modes.
When using I2S format, the first bit in a half-frame (containing one left or right sample) gets sampled on
the second rising edge of the SCK after a LRCK edge. When using Aligned mode, the first bit in a half-frame
gets sampled on the first rising edge of SCK following a LRCK edge.
For data being received on SDIN the sample value can be either right or left-aligned inside a half-frame, as
specified in CONFIG.ALIGN on page 135. CONFIG.ALIGN on page 135 affects only the decoding of the
incoming samples (SDIN), while the outgoing samples (SDOUT) are always left-aligned (or justified).
When using left-alignment, each half-frame starts with the MSB of the sample value (both for data being
sent on SDOUT and received on SDIN).
When using right-alignment, each half-frame of data being received on SDIN ends with the LSB of the
sample value, while each half-frame of data being sent on SDOUT starts with the MSB of the sample value
(same as for left-alignment).
In Master mode, the size of a half-frame (in number of SCK periods) equals the sample width (in number
of bits), and in this case the alignment setting does not care as each half-frame in any case will start with
the MSB and end with the LSB of the sample value.
In slave mode, however, the sample width does not need to equal the frame size. This means you might
have extra or fewer SCK pulses per half-frame than what the sample width specified in CONFIG.SWIDTH
requires.
In the case where we use left-alignment and the number of SCK pulses per half-frame is higher than the
sample width, the following will apply:
• For data received on SDIN, all bits after the LSB of the sample value will be discarded.
• For data sent on SDOUT, all bits after the LSB of the sample value will be 0.
In the case where we use left-alignment and the number of SCK pulses per frame is lower than the
sample width, the following will apply:
• Data sent and received on SDOUT and SDIN will be truncated with the LSBs being removed first.
In the case where we use right-alignment and the number of SCK pulses per frame is higher than the
sample width, the following will apply:
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• For data received on SDIN, all bits before the MSB of the sample value will be discarded.
• For data sent on SDOUT, all bits after the LSB of the sample value will be 0 (same behavior as for leftalignment).
In the case where we use right-alignment and the number of SCK pulses per frame is lower than the
sample width, the following will apply:
• Data received on SDIN will be sign-extended to "sample width" number of bits before being written to
memory.
• Data sent on SDOUT will be truncated with the LSBs being removed first (same behavior as for leftalignment).
frame
left
LRCK
right
left
SCK
SDIN or SDOUT
Figure 24: I2S format. CONFIG.SWIDTH equalling half-frame size.
frame
LRCK
right
left
left
SCK
SDATA
Figure 25: Aligned format. CONFIG.SWIDTH equalling half-frame size.
6.7.7 EasyDMA
The I2S module implements EasyDMA for accessing internal Data RAM without CPU intervention.
The source and destination pointers for the TX and RX data are configured in TXD.PTR on page 136 and
RXD.PTR on page 136. The memory pointed to by these pointers will only be read or written when TX or
RX are enabled in CONFIG.TXEN on page 134 and CONFIG.RXEN on page 133.
The addresses written to the pointer registers TXD.PTR on page 136 and RXD.PTR on page 136 are
double-buffered in hardware, and these double buffers are updated for every RXTXD.MAXCNT on page
137 words (containing one or more samples) read/written from/to memory. The events TXPTRUPD and
RXPTRUPD are generated whenever the TXD.PTR and RXD.PTR are transferred to these double buffers.
If TXD.PTR on page 136 is not pointing to the Data RAM region when transmission is enabled, or
RXD.PTR on page 136 is not pointing to the Data RAM region when reception is enabled, an EasyDMA
transfer may result in a HardFault and/or memory corruption. See Memory on page 20 for more
information about the different memory regions.
Due to the nature of I2S, where the number of transmitted samples always equals the number of received
samples (at least when both TX and RX are enabled), one common register RXTXD.MAXCNT on page
137 is used for specifying the sizes of these two memory buffers. The size of the buffers is specified in
a number of 32-bit words. Such a 32-bit memory word can either contain four 8-bit samples, two 16-bit
samples or one right-aligned 24-bit sample sign extended to 32 bit.
In stereo mode (CONFIG.CHANNELS=Stereo), the samples are stored as "left and right sample pairs" in
memory. Figure Memory mapping for 8 bit stereo. CONFIG.SWIDTH = 8Bit, CONFIG.CHANNELS = Stereo.
on page 124, Memory mapping for 16 bit stereo. CONFIG.SWIDTH = 16Bit, CONFIG.CHANNELS = Stereo.
on page 124 and Memory mapping for 24 bit stereo. CONFIG.SWIDTH = 24Bit, CONFIG.CHANNELS =
Stereo. on page 125 show how the samples are mapped to memory in this mode. The mapping is valid
for both RX and TX.
In mono mode (CONFIG.CHANNELS=Left or Right), RX sample from only one channel in the frame is
stored in memory, the other channel sample is ignored. Illustrations Memory mapping for 8 bit mono.
CONFIG.SWIDTH = 8Bit, CONFIG.CHANNELS = Left. on page 124, Memory mapping for 16 bit mono, left
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channel only. CONFIG.SWIDTH = 16Bit, CONFIG.CHANNELS = Left. on page 124 and Memory mapping
for 24 bit mono, left channel only. CONFIG.SWIDTH = 24Bit, CONFIG.CHANNELS = Left. on page 125
show how RX samples are mapped to memory in this mode.
For TX, the same outgoing sample read from memory is transmitted on both left and right in a frame,
resulting in a mono output stream.
31
24 23
16 15
8 7
0
x.PTR
Right sample 1
Left sample 1
Right sample 0
Left sample 0
x.PTR + 4
Right sample 3
Left sample 3
Right sample 2
Left sample 2
Right sample
n-1
Left sample
n-1
Right sample
n-2
Left sample
n-2
x.PTR + (n*2) - 4
Figure 26: Memory mapping for 8 bit stereo. CONFIG.SWIDTH = 8Bit, CONFIG.CHANNELS = Stereo.
31
24 23
16 15
8 7
0
x.PTR
Left sample 3
Left sample 2
Left sample 1
Left sample 0
x.PTR + 4
Left sample 7
Left sample 6
Left sample 5
Left sample 4
Left sample
n-1
Left sample
n-2
Left sample
n-3
Left sample
n-4
x.PTR + n - 4
Figure 27: Memory mapping for 8 bit mono. CONFIG.SWIDTH = 8Bit, CONFIG.CHANNELS = Left.
31
16 15
0
x.PTR
Right sample 0
Left sample 0
x.PTR + 4
Right sample 1
Left sample 1
Right sample n - 1
Left sample n - 1
x.PTR + (n*4) - 4
Figure 28: Memory mapping for 16 bit stereo. CONFIG.SWIDTH = 16Bit, CONFIG.CHANNELS = Stereo.
31
16 15
0
x.PTR
Left sample 1
Left sample 0
x.PTR + 4
Left sample 3
Left sample 2
Left sample n - 1
Left sample n - 2
x.PTR + (n*2) - 4
Figure 29: Memory mapping for 16 bit mono, left channel
only. CONFIG.SWIDTH = 16Bit, CONFIG.CHANNELS = Left.
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31
23
0
x.PTR
Sign ext.
Left sample 0
x.PTR + 4
Sign ext.
Right sample 0
x.PTR + (n*8) - 8
Sign ext.
Left sample n - 1
x.PTR + (n*8) - 4
Sign ext.
Right sample n - 1
Figure 30: Memory mapping for 24 bit stereo. CONFIG.SWIDTH = 24Bit, CONFIG.CHANNELS = Stereo.
31
23
0
x.PTR
Sign ext.
Left sample 0
x.PTR + 4
Sign ext.
Left sample 1
x.PTR + (n*4) - 4
Sign ext.
Left sample n - 1
Figure 31: Memory mapping for 24 bit mono, left channel
only. CONFIG.SWIDTH = 24Bit, CONFIG.CHANNELS = Left.
6.7.8 Module operation
Described here is a typical operating procedure for the I2S module.
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1. Configure the I2S module using the CONFIG registers
// Enable reception
NRF_I2S->CONFIG.RXEN = (I2S_CONFIG_RXEN_RXEN_Enabled CONFIG.TXEN = (I2S_CONFIG_TXEN_TXEN_Enabled CONFIG.MCKEN = (I2S_CONFIG_MCKEN_MCKEN_Enabled CONFIG.MCKFREQ = I2S_CONFIG_MCKFREQ_MCKFREQ_32MDIV8 CONFIG.RATIO = I2S_CONFIG_RATIO_RATIO_256X CONFIG.SWIDTH = I2S_CONFIG_SWIDTH_SWIDTH_16Bit CONFIG.ALIGN = I2S_CONFIG_ALIGN_ALIGN_Left CONFIG.FORMAT = I2S_CONFIG_FORMAT_FORMAT_I2S CONFIG.CHANNELS = I2S_CONFIG_CHANNELS_CHANNELS_Stereo PSEL.MCK = (0 EVENTS_TXPTRUPD
{
}
!= 0)
NRF_I2S->TXD.PTR = my_next_tx_buf;
NRF_I2S->EVENTS_TXPTRUPD = 0;
if(NRF_I2S->EVENTS_RXPTRUPD != 0)
{
}
NRF_I2S->RXD.PTR = my_next_rx_buf;
NRF_I2S->EVENTS_RXPTRUPD = 0;
6.7.9 Pin configuration
The MCK, SCK, LRCK, SDIN and SDOUT signals associated with the I2S module are mapped to physical pins
according to the pin numbers specified in the PSEL.x registers.
These pins are acquired whenever the I2S module is enabled through the register ENABLE on page 133.
When a pin is acquired by the I2S module, the direction of the pin (input or output) will be configured
automatically, and any pin direction setting done in the GPIO module will be overridden. The directions for
the various I2S pins are shown below in GPIO configuration before enabling peripheral (master mode) on
page 127 and GPIO configuration before enabling peripheral (slave mode) on page 128.
To secure correct signal levels on the pins when the system is in OFF mode, and when the I2S module is
disabled, these pins must be configured in the GPIO peripheral directly.
I2S signal
I2S pin
Direction
Output value
MCK
As specified in PSEL.MCK
Output
0
LRCK
As specified in PSEL.LRCK
Output
0
SCK
As specified in PSEL.SCK
Output
0
SDIN
As specified in PSEL.SDIN
Input
Not applicable
SDOUT
As specified in PSEL.SDOUT
Output
0
Comment
Table 45: GPIO configuration before enabling peripheral (master mode)
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I2S signal
I2S pin
Direction
Output value
MCK
As specified in PSEL.MCK
Output
0
LRCK
As specified in PSEL.LRCK
Input
Not applicable
SCK
As specified in PSEL.SCK
Input
Not applicable
SDIN
As specified in PSEL.SDIN
Input
Not applicable
SDOUT
As specified in PSEL.SDOUT
Output
0
Comment
Table 46: GPIO configuration before enabling peripheral (slave mode)
6.7.10 Registers
Base address Peripheral
Instance
0x50028000
I2S : S
0x40028000
I2S
I2S : NS
Secure mapping
DMA security
Description
US
SA
Inter-IC Sound
Configuration
Table 47: Instances
Register
Offset
Security
Description
TASKS_START
0x000
Starts continuous I2S transfer. Also starts MCK generator when this is enabled.
TASKS_STOP
0x004
Stops I2S transfer. Also stops MCK generator. Triggering this task will cause the
SUBSCRIBE_START
0x080
Subscribe configuration for task START
SUBSCRIBE_STOP
0x084
Subscribe configuration for task STOP
EVENTS_RXPTRUPD
0x104
The RXD.PTR register has been copied to internal double-buffers. When the
STOPPED event to be generated.
I2S module is started and RX is enabled, this event will be generated for every
RXTXD.MAXCNT words that are received on the SDIN pin.
EVENTS_STOPPED
0x108
I2S transfer stopped.
EVENTS_TXPTRUPD
0x114
The TDX.PTR register has been copied to internal double-buffers. When the
I2S module is started and TX is enabled, this event will be generated for every
RXTXD.MAXCNT words that are sent on the SDOUT pin.
PUBLISH_RXPTRUPD
0x184
Publish configuration for event RXPTRUPD
PUBLISH_STOPPED
0x188
Publish configuration for event STOPPED
PUBLISH_TXPTRUPD
0x194
Publish configuration for event TXPTRUPD
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
ENABLE
0x500
Enable I2S module.
CONFIG.MODE
0x504
I2S mode.
CONFIG.RXEN
0x508
Reception (RX) enable.
CONFIG.TXEN
0x50C
Transmission (TX) enable.
CONFIG.MCKEN
0x510
Master clock generator enable.
CONFIG.MCKFREQ
0x514
Master clock generator frequency.
CONFIG.RATIO
0x518
MCK / LRCK ratio.
CONFIG.SWIDTH
0x51C
Sample width.
CONFIG.ALIGN
0x520
Alignment of sample within a frame.
CONFIG.FORMAT
0x524
Frame format.
CONFIG.CHANNELS
0x528
Enable channels.
RXD.PTR
0x538
Receive buffer RAM start address.
TXD.PTR
0x540
Transmit buffer RAM start address.
RXTXD.MAXCNT
0x550
Size of RXD and TXD buffers.
PSEL.MCK
0x560
Pin select for MCK signal.
PSEL.SCK
0x564
Pin select for SCK signal.
PSEL.LRCK
0x568
Pin select for LRCK signal.
4418_1315 v1.0
128
Peripherals
Register
Offset
Security
Description
PSEL.SDIN
0x56C
Pin select for SDIN signal.
PSEL.SDOUT
0x570
Pin select for SDOUT signal.
Table 48: Register overview
6.7.10.1 TASKS_START
Address offset: 0x000
Starts continuous I2S transfer. Also starts MCK generator when this is enabled.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_START
Starts continuous I2S transfer. Also starts MCK generator
when this is enabled.
Trigger
1
Trigger task
6.7.10.2 TASKS_STOP
Address offset: 0x004
Stops I2S transfer. Also stops MCK generator. Triggering this task will cause the STOPPED event to be
generated.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_STOP
Stops I2S transfer. Also stops MCK generator. Triggering this
task will cause the STOPPED event to be generated.
Trigger
1
Trigger task
6.7.10.3 SUBSCRIBE_START
Address offset: 0x080
Subscribe configuration for task START
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task START will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.7.10.4 SUBSCRIBE_STOP
Address offset: 0x084
Subscribe configuration for task STOP
4418_1315 v1.0
129
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task STOP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.7.10.5 EVENTS_RXPTRUPD
Address offset: 0x104
The RXD.PTR register has been copied to internal double-buffers. When the I2S module is started and RX is
enabled, this event will be generated for every RXTXD.MAXCNT words that are received on the SDIN pin.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_RXPTRUPD
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
The RXD.PTR register has been copied to internal doublebuffers. When the I2S module is started and RX is enabled,
this event will be generated for every RXTXD.MAXCNT
words that are received on the SDIN pin.
NotGenerated
0
Event not generated
Generated
1
Event generated
6.7.10.6 EVENTS_STOPPED
Address offset: 0x108
I2S transfer stopped.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_STOPPED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
I2S transfer stopped.
6.7.10.7 EVENTS_TXPTRUPD
Address offset: 0x114
The TDX.PTR register has been copied to internal double-buffers. When the I2S module is started and TX is
enabled, this event will be generated for every RXTXD.MAXCNT words that are sent on the SDOUT pin.
4418_1315 v1.0
130
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_TXPTRUPD
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
The TDX.PTR register has been copied to internal doublebuffers. When the I2S module is started and TX is enabled,
this event will be generated for every RXTXD.MAXCNT
words that are sent on the SDOUT pin.
NotGenerated
0
Event not generated
Generated
1
Event generated
6.7.10.8 PUBLISH_RXPTRUPD
Address offset: 0x184
Publish configuration for event RXPTRUPD
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event RXPTRUPD will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.7.10.9 PUBLISH_STOPPED
Address offset: 0x188
Publish configuration for event STOPPED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event STOPPED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.7.10.10 PUBLISH_TXPTRUPD
Address offset: 0x194
Publish configuration for event TXPTRUPD
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
4418_1315 v1.0
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event TXPTRUPD will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
131
Peripherals
6.7.10.11 INTEN
Address offset: 0x300
Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
F
Reset 0x00000000
ID
Access
Field
B
RW RXPTRUPD
C
F
C B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Enable or disable interrupt for event RXPTRUPD
RW STOPPED
Enable or disable interrupt for event STOPPED
RW TXPTRUPD
Enable or disable interrupt for event TXPTRUPD
6.7.10.12 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
F
Reset 0x00000000
ID
Access
Field
B
RW RXPTRUPD
C
F
C B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to enable interrupt for event RXPTRUPD
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW STOPPED
Write '1' to enable interrupt for event STOPPED
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW TXPTRUPD
Write '1' to enable interrupt for event TXPTRUPD
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.7.10.13 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
F
Reset 0x00000000
ID
Access
Field
B
RW RXPTRUPD
4418_1315 v1.0
C B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Clear
1
Description
Write '1' to disable interrupt for event RXPTRUPD
Disable
132
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
F
Reset 0x00000000
ID
C
F
Access
Field
C B
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW STOPPED
Write '1' to disable interrupt for event STOPPED
RW TXPTRUPD
Write '1' to disable interrupt for event TXPTRUPD
6.7.10.14 ENABLE
Address offset: 0x500
Enable I2S module.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW ENABLE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Enable I2S module.
6.7.10.15 CONFIG.MODE
Address offset: 0x504
I2S mode.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW MODE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Master
0
Slave
1
Description
I2S mode.
Master mode. SCK and LRCK generated from internal master
clcok (MCK) and output on pins defined by PSEL.xxx.
Slave mode. SCK and LRCK generated by external master
and received on pins defined by PSEL.xxx
6.7.10.16 CONFIG.RXEN
Address offset: 0x508
Reception (RX) enable.
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Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW RXEN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Disabled
0
Enabled
1
Description
Reception (RX) enable.
Reception disabled and now data will be written to the
RXD.PTR address.
Reception enabled.
6.7.10.17 CONFIG.TXEN
Address offset: 0x50C
Transmission (TX) enable.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000001
ID
Access
Field
A
RW TXEN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
Transmission (TX) enable.
Disabled
0
Enabled
1
Transmission disabled and now data will be read from the
RXD.TXD address.
Transmission enabled.
6.7.10.18 CONFIG.MCKEN
Address offset: 0x510
Master clock generator enable.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000001
ID
Access
Field
A
RW MCKEN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Disabled
0
Enabled
1
Description
Master clock generator enable.
Master clock generator disabled and PSEL.MCK not
connected(available as GPIO).
Master clock generator running and MCK output on
PSEL.MCK.
6.7.10.19 CONFIG.MCKFREQ
Address offset: 0x514
Master clock generator frequency.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x20000000
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW MCKFREQ
4418_1315 v1.0
Value ID
Value
Description
32MDIV8
0x20000000
32 MHz / 8 = 4.0 MHz
32MDIV10
0x18000000
32 MHz / 10 = 3.2 MHz
32MDIV11
0x16000000
32 MHz / 11 = 2.9090909 MHz
32MDIV15
0x11000000
32 MHz / 15 = 2.1333333 MHz
Master clock generator frequency.
134
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x20000000
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
Value ID
Value
Description
32MDIV16
0x10000000
32 MHz / 16 = 2.0 MHz
32MDIV21
0x0C000000
32 MHz / 21 = 1.5238095
32MDIV23
0x0B000000
32 MHz / 23 = 1.3913043 MHz
32MDIV30
0x08800000
32 MHz / 30 = 1.0666667 MHz
32MDIV31
0x08400000
32 MHz / 31 = 1.0322581 MHz
32MDIV32
0x08000000
32 MHz / 32 = 1.0 MHz
32MDIV42
0x06000000
32 MHz / 42 = 0.7619048 MHz
32MDIV63
0x04100000
32 MHz / 63 = 0.5079365 MHz
32MDIV125
0x020C0000
32 MHz / 125 = 0.256 MHz
6.7.10.20 CONFIG.RATIO
Address offset: 0x518
MCK / LRCK ratio.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A
Reset 0x00000006
ID
Access
Field
A
RW RATIO
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0
Value ID
Value
Description
32X
0
LRCK = MCK / 32
48X
1
LRCK = MCK / 48
64X
2
LRCK = MCK / 64
96X
3
LRCK = MCK / 96
128X
4
LRCK = MCK / 128
192X
5
LRCK = MCK / 192
256X
6
LRCK = MCK / 256
384X
7
LRCK = MCK / 384
512X
8
LRCK = MCK / 512
MCK / LRCK ratio.
6.7.10.21 CONFIG.SWIDTH
Address offset: 0x51C
Sample width.
Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000001
ID
Access
Field
A
RW SWIDTH
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
8Bit
0
8 bit.
16Bit
1
16 bit.
24Bit
2
24 bit.
Sample width.
6.7.10.22 CONFIG.ALIGN
Address offset: 0x520
Alignment of sample within a frame.
4418_1315 v1.0
135
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW ALIGN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Left
0
Left-aligned.
Right
1
Right-aligned.
Alignment of sample within a frame.
6.7.10.23 CONFIG.FORMAT
Address offset: 0x524
Frame format.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW FORMAT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
I2S
0
Original I2S format.
Aligned
1
Alternate (left- or right-aligned) format.
Frame format.
6.7.10.24 CONFIG.CHANNELS
Address offset: 0x528
Enable channels.
Bit number
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 6 5 4 3 2 1 0
ID
A A
Reset 0x00000000
ID
Access
Field
A
RW CHANNELS
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Stereo
0
Stereo.
Left
1
Left only.
Right
2
Right only.
Enable channels.
6.7.10.25 RXD.PTR
Address offset: 0x538
Receive buffer RAM start address.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW PTR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Receive buffer Data RAM start address. When receiving,
words containing samples will be written to this address.
This address is a word aligned Data RAM address.
6.7.10.26 TXD.PTR
Address offset: 0x540
Transmit buffer RAM start address.
4418_1315 v1.0
136
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW PTR
Value ID
Value
Description
Transmit buffer Data RAM start address. When transmitting,
words containing samples will be fetched from this address.
This address is a word aligned Data RAM address.
6.7.10.27 RXTXD.MAXCNT
Address offset: 0x550
Size of RXD and TXD buffers.
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW MAXCNT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Size of RXD and TXD buffers in number of 32 bit words.
6.7.10.28 PSEL.MCK
Address offset: 0x560
Pin select for MCK signal.
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
ID
Access
Field
A
RW PIN
C
RW CONNECT
A A A A A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.7.10.29 PSEL.SCK
Address offset: 0x564
Pin select for SCK signal.
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW PIN
C
RW CONNECT
Value ID
A A A A A
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.7.10.30 PSEL.LRCK
Address offset: 0x568
Pin select for LRCK signal.
4418_1315 v1.0
137
Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW PIN
Value ID
C
RW CONNECT
A A A A A
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.7.10.31 PSEL.SDIN
Address offset: 0x56C
Pin select for SDIN signal.
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
A A A A A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
Value ID
A
RW PIN
C
RW CONNECT
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.7.10.32 PSEL.SDOUT
Address offset: 0x570
Pin select for SDOUT signal.
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
A A A A A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
Value ID
A
RW PIN
C
RW CONNECT
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.7.11 Electrical specification
6.7.11.1 I2S timing specification
Symbol
Description
Min.
tS_SDIN
SDIN setup time before SCK rising
20
ns
tH_SDIN
SDIN hold time after SCK rising
15
ns
tS_SDOUT
SDOUT setup time after SCK falling
40
ns
tH_SDOUT
SDOUT hold time before SCK falling
6
ns
tSCK_LRCK
SCLK falling to LRCK edge
-5
5
ns
fMCK
MCK frequency
4000
kHz
fLRCK
LRCK frequency
48
kHz
fSCK
SCK frequency
2000
kHz
DCCK
Clock duty cycle (MCK, LRCK, SCK)
55
%
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Typ.
0
Max.
Units
Peripherals
tSCK_LRCK
LRCK
SCK
tS_SDIN
tH_SDIN
SDIN
tH_SDOUT
tS_SDOUT
SDOUT
Figure 32: I2S timing diagram
6.8 KMU — Key management unit
The key management unit (KMU) enforces access policies to a subset region of user information
configuration register (UICR). This subset region is used for storing cryptographic key values inside the key
slots, which the CPU has no access to.
In total there are 128 key slots available, where each key slot can store one 128-bit key value together with
an access policy and a destination address for the key value. Multiple key slots can be combined in order
to support key sizes larger than 128 bits. The access policy of a key slot governs if and how a key value can
be used, while the destination address determines where in the memory map the KMU pushes the key
value upon a request from the CPU.
Key slots can be configured to be pushed directly into write-only key registers in cryptographic
accelerators, like e.g. CryptoCell, without exposing the key value itself to the CPU. This enables the CPU to
use the key values stored inside the key slots for cryptographic operations without being exposed to the
key value.
Access to the KMU, and the key slots in the UICR, is only allowed from secure mode.
6.8.1 Functional view
From a functional view the UICR is divided into two different regions, one-time programmable (OTP)
memory and key storage.
UICR offset
0x1000
User information configuration register (UICR)
infopage
Regular UICR
OTP
Functional view
Key storage
User defined
Key headers
Part specific instantiation
Key values
Permission legend:
KEYSLOT.
CONFIG[0]
KEYSLOT.
CONFIG[n]
(…)
KEYSLOT.
KEY[0]
(…)
Write-once per halfword limitation,
always readable
KEYSLOT.
KEY[n]
Write-once per halfword limitation,
always readable
DEST
VALUE[0]
PERM
STATE
PUSH
READ
VALUE[1]
VALUE[3]
Write-once per halfword limitation,
restricted usage and readability
based on key header configuration
WRITE
Finite-state machine (FSM)
Figure 33: Memory map overview
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OTP
One-time programmable (OTP) memory is typically used for holding values that are written once, and then
never to be changed again throughout the product lifetime. The OTP region of UICR is emulated by placing
a write-once per halfword limitation on registers defined here.
Key storage
The key storage region contains multiple key slots, where each slot consists of a key header and an
associated key value. The key value is limited to 128 bits. Any key size greater than 128 bits must be
divided and distributed over multiple key slot instances.
Key headers are allocated an address range of 0x400 in the UICR memory map, allowing a total of 128 keys
to be addressable inside the key storage region.
Note: The use of the key storage region in UICR should be limited to keys with a certain life span,
and not per-session derived keys where the CPU is involved in the key exchange.
6.8.2 Access control
Access control to the underlying UICR infopage in flash is enforced by a hardware finite-state machine
(FSM). The FSM can allow or block transactions, depending both on the security of the transaction (secure
or non-secure) and on the type of register being written and/or read.
Access type
Key headers
Key values
Read
Allowed
Restricted
Write
Restricted
Restricted
Table 49: Access control
Any restricted access requires an explicit key slot selection through the KMU register interface. Any illegal
access to restricted key slot registers will be blocked and word 0xDEADDEAD will be returned on the AHB.
The OTP region has individual access control behavior, while access control to the key storage region is
configured on a per key slot basis. The KMU FSM operates on only one key slot instance at a time, and
the permissions and the usage restriction for a key value associated with a key slot can be configured
individually.
Note: Even if the KMU can be configured as non-secure, all non-secure transactions will be
blocked.
6.8.3 Protecting the UICR content
The UICR content can be protected against device-internal NVMC.ERASEALL requests, in addition to
device-external ERASEALL requests, through the CTRL-AP interface. This feature is useful if the firmware
designers want to prevent the OTP region from being erased.
Since enabling this step will permanently disable erase for the UICR, the procedure requires an
implementation defined 32-bit word to be written into the UICR's ERASEPROTECT register.
In case of a field return handling, it is still possible to erase the UICR even if the ERASEPROTECT is set. If
this functionality is desired, the secure boot code must implement a secure communication channel over
the CTRL-AP mailbox interface. Upon successful authentication of the external party, the secure boot code
can temporarily re-enable the CTRL-AP ERASEALL functionality.
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6.8.4 Usage
This section describes the specific KMU and UICR behavior in more detail, to help the reader get a better
overview of KMU's features and the intended usage.
6.8.4.1 OTP
The OTP region of the UICR contains a user-defined static configuration of the device. The KMU emulates
the OTP functionality by placing a write-once per halfword limitation of registers defined in this region, i.e.
only halfwords containing all '1's can be written.
An OTP write transaction must consist of a full 32-bit word. Both halfwords can either be written
simultaneously or one at a time. The KMU FSM will block any write to a halfword in the OTP region, if the
initial value of this halfword is not 0xFFFF. When writing halfwords one at a time, the non-active halfword
must be masked as 0xFFFF, otherwise the request will be blocked. For example, writing 0x1234XXXX to an
OTP destination address which already contains the value 0xFFFFAABB, must be configured as 0x1234FFFF.
The OTP destination address will contain the value 0x1234AABB after both write transactions have been
processed.
The KMU will also only allow secure AHB write transactions into the OTP region of the UICR. Any AHB
write transaction to this region that does not satisfy the above requirements will be ignored, and the
STATUS.BLOCKED register will be set to '1'.
6.8.4.2 Key storage
The key storage region of the UICR can contain multiple keys of different type, including symmetrical keys,
hashes, public/private key pairs and other device secrets. One of the key features of the KMU, is that these
device secrets can be installed and made available for use in cryptographic operations without revealing
the actual secret values.
Keys in this region will typically have a certain life span. The region is not designed to be used for persession derived keys where the non-secure side (i.e. application) is participating in the key exchange.
All key storage is done through the concept of multiple key slots, where each key slot instance consists
of one key header and an associated key value. Each key header supports the configuration of usage
permissions and an optional secure destination address.
The key header secure destination address option enables the KMU to push the associated key value
over a dedicated secure APB to a pre-configured secure location within the memory map. Such locations
typically include a write-only key register of the hardware cryptograhic accelerator, allowing the KMU to
distribute keys within the system without compromising the key values.
One key slot instance can store a key value of maximum 128 bits. If a key size exceeds this limit, the key
value itself must be split over multiple key slot instances.
The following usage and read permissions scheme is applicable for each key slot:
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State
Push
Read
Write
Description
Enabled
Enabled
Default flash erase value. Key slot cannot be pushed, write is enabled.
(1)
(1)
Enabled
Disabled
(1)
(0)
Disabled
Disabled
(0)
(0)
Enabled
Disabled
(0)
(1)
(0)
-
-
-
Active (1) Enabled
(1)
Active (1) Enabled
(1)
Active (1) Enabled
(1)
Active (1) Disabled
Revoked
Key slot is active, push is enabled. Key slot VALUE registers can be read, but write is disabled.
Key slot is active, push is enabled. Read and write to key slot VALUE registers are disabled.
Key slot is active, push is disabled. Key slot VALUE registers can be read, but write is disabled.
Key slot is revoked. Cannot be read or pushed over secure APB regardless of the permission settings.
(0)
Table 50: Valid key slot permission schemes
6.8.4.2.1 Selecting a key slot
The KMU FSM is designed to process only one key slot at a time, effectively operating as a memory
protection unit for the key storage region. Whenever a key slot is selected, the KMU will allow access to
writing, reading, and/or pushing the associated key value according to the selected slot configuration.
A key slot must be selected prior to use, by writing the key slot ID into the KMU SELECTKEYSLOT register.
Because the reset value of this register is 0x00000000, there is no key slot associated with ID=0 and no slot
is selected by default. All key slots are addressed using IDs from 1 to 128.
SELECTED status is set when a key slot is selected, and a read or write acccess to that keyslot occurs.
BLOCKED status is set when any illegal access to key slot registers is detected.
When the use of the particular key slot is stopped, the key slot selection in SELECTKEYSLOT must be set
back to '0'.
By default, all KMU key slots will consist of a 128-bit key value of '1's, where the key headers have no
secure destination address, or any usage and read restrictions.
6.8.4.2.2 Writing to a key slot
Writing a key slot into UICR is a five-step process.
1. Select which key slot the KMU shall operate on by writing the desired key slot ID into KMU>SELECTKEYSLOT. The selected key slot must be empty in order to add a new entry to UICR.
2. If the key value shall be pushable over secure APB, the destination address of the recipient must be
configured in register KEYSLOT.CONFIG[ID-1].DEST.
3. Write the 128-bit key value into KEYSLOT.KEY[ID-1].VALUE[0-3].
4. Write the desired key slot permissions into KEYSLOT.CONFIG[ID-1].PERM, including any applicable
usage restrictions.
5. Select key slot 0.
In case the total key size is greater than 128 bits, the key value itself must be split into 128-bit segments
and written to multiple key slot instances. Steps 1 through 5 above must be repeated for the entire key
size.
Note: If a key slot is configured as readable, and KEYSLOT.CONFIG[ID-1].DEST is not to be used, it
is recommended to disable the push bit in KEYSLOT.CONFIG[ID-1].PERM when configuring key slot
permissions.
Note: A key value distributed over multiple key slots should use the same key slot configuration in
its key headers, but the secure destination address for each key slot instance must be incremented
by 4 words (128 bits) for each key slot instance spanned.
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Note: Write to flash must be enabled in NVMC->CONFIG prior to writing keys to flash, and
subsequently disabled once writing is complete.
Steps 1 through 5 above will be blocked if any of the following violations are detected:
•
•
•
•
No key slot selected
Non-empty key slot selected
NVM destination address not empty
AHB write to KEYSLOT.KEY[ID-1].VALUE[0-3] registers not belonging to selected key slot
6.8.4.2.3 Reading a key value
Key slots that are configured as readable can have their key value read directly from the UICR memory
map by the CPU.
Readable keys are typically used during the secure boot sequence, where the CPU is involved in falsifying
or verifying the integrity of the system. Since the CPU is involved in this decision process, it makes little
sense not to trust the CPU having access to the actual key value but ultimately trust the decision of the
integrity check. Another use-case for readable keys is if the key type in question does not have a HW
peripheral in the platform that is able to accept such keys over secure APB.
Reading a key value from the UICR is a three-step process:
1. Select the key slot which the KMU shall operate on by writing the desired key slot ID into KMU>SELECTKEYSLOT.
2. If STATE and READ permission requirements are fulfilled as defined in KEYSLOT.CONFIG[ID-1].PERM, the
key value can be read from region KEYSLOT.KEY[ID-1].VALUE[0-3] for selected key slot.
3. Select key slot 0.
Step 2 will be blocked and word 0xDEADDEAD will be returned on AHB if any of the following violations
are detected:
•
•
•
•
No key slot selected
Key slot not configured as readable
Key slot is revoked
AHB read to KEYSLOT.KEY[ID-1].VALUE[0-3] registers not belonging to selected key slot
6.8.4.2.4 Push over secure APB
Key slots that are configured as non-readable cannot be read by the CPU regardless of the mode the
system is in, and must be pushed over secure APB in order to use the key value for cryptographic
operations.
The secure APB destination address is set in the key slot configuration DEST register. Such destination
addresses are typically write-only key registers in a hardware cryptographic accelerators memory map. The
secure APB allows key slots to be utilized by the software side, without exposing the key value itself.
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APB
APB
Secure APB
NVMC
FICR
2:1 MUX
2:1 MUX
Write-only key
registers
Write-only key
registers
Peripheral[0]
Peripheral[n]
UICR
AHB
EVENTS_KEYSLOT_PUSHED
TASKS_PUSH_KEYSLOT
NVMC
SELECTKEYSLOT
KMU
APB
Figure 34: Tasks and events pattern for key slots
Pushing a key slot over secure APB is a four-step process:
1. Select the key slot on which the KMU shall operate by writing the desired key slot ID into KMU>SELECTKEYSLOT.
2. Start TASKS_PUSH_KEYSLOT to initiate a secure APB transaction, writing the 128-bit key value
associated with the selected key slot into address defined in KEYSLOT.CONFIG[ID-1].DEST.
3. After completing the secure APB transaction, the 128-bit key value is ready for use by the peripheral
and EVENTS_KEYSLOT_PUSHED is triggered.
4. Select key slot 0.
Note: If a key value is distributed over multiple key slots due to its key size, exceeding the
maximum 128-bit key value limitation, then each distributed key slot must be pushed individually in
order to transfer the entire key value over secure APB.
Step 3 will trigger other events than EVENTS_KEYSLOT_PUSHED if the following violations are detected:
• EVENTS_KEYSLOT_ERROR:
• If no key slot is selected
• If a key slot has no destination address configured
• If when pushing a key slot, flash or peripheral returns an error
• If pushing a key slot when push permissions are disabled
• If attempting to push a key slot with default permissions
• EVENTS_KEYSLOT_REVOKED if a key slot is marked as revoked in its key header configuration
6.8.4.2.5 Revoking the key slots
All key slots within the key storage area can be marked as revoked.
To revoke any key slots, write to the STATE field in the KEYSLOT.CONFIG[ID-1].PERM register. The following
rules apply to keys that have been revoked:
1. Key slots that have the PUSH field enabled in PERM register can no longer be pushed. If a revoked key
slot is selected and task TASKS_PUSH_KEYSLOT is started, the event EVENTS_KEYSLOT_REVOKED is
triggered.
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2. Key slots that have the READ field enabled in PERM register can no longer be read. Any read operation
to a revoked key value will return word 0xDEADDEAD.
3. Previously pushed key values stored in a peripheral write-only key register are not affected by key
revocation. If secure code wants to enforce that a revoked key is no longer usable by a peripheral for
cryptographic operations, the secure code should disable or reset the peripheral in question.
6.8.4.3 STATUS register
The KMU uses a STATUS register to indicate its status of operation. The SELECTED bit will be asserted
whenever the currently selected key slot is successfully read from or written to.
All read or write operations to other key slots than what is currently selected in KMU->SELECTKEYSLOT
will assert the BLOCKED bit. The BLOCKED bit will also be asserted if the KMU fails to select a key slot, or
if a request has been blocked due to an access violation. Normal operation using the KMU should never
trigger the BLOCKED bit. If this bit is triggered during the development phase, it indicates that the code is
using the KMU incorrectly.
The STATUS register is reset every time register SELECTKEYSLOT is written.
6.8.5 Registers
Base address Peripheral
Instance
0x50039000
KMU : S
0x40039000
KMU
KMU : NS
Secure mapping
DMA security
Description
SPLIT
NA
Key management unit
Configuration
Table 51: Instances
Register
Offset
TASKS_PUSH_KEYSLOT
0x0000
Security
Description
Push a key slot over secure APB
EVENTS_KEYSLOT_PUSHED 0x100
Key slot successfully pushed over secure APB
EVENTS_KEYSLOT_REVOKED0x104
Key slot has been revoked and cannot be tasked for selection
EVENTS_KEYSLOT_ERROR 0x108
No key slot selected, no destination address defined, or error during push
operation
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
INTPEND
0x30C
Pending interrupts
STATUS
0x40C
Status bits for KMU operation
SELECTKEYSLOT
0x500
Select key slot to be read over AHB or pushed over secure APB when
TASKS_PUSH_KEYSLOT is started
Table 52: Register overview
6.8.5.1 TASKS_PUSH_KEYSLOT
Address offset: 0x0000
Push a key slot over secure APB
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_PUSH_KEYSLOT
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Trigger task
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6.8.5.2 EVENTS_KEYSLOT_PUSHED
Address offset: 0x100
Key slot successfully pushed over secure APB
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW EVENTS_KEYSLOT_PUSHED
Value ID
Value
Description
Key slot successfully pushed over secure APB
NotGenerated
0
Event not generated
Generated
1
Event generated
6.8.5.3 EVENTS_KEYSLOT_REVOKED
Address offset: 0x104
Key slot has been revoked and cannot be tasked for selection
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW EVENTS_KEYSLOT_REVOKED
Value ID
Value
Description
Key slot has been revoked and cannot be tasked for
selection
NotGenerated
0
Event not generated
Generated
1
Event generated
6.8.5.4 EVENTS_KEYSLOT_ERROR
Address offset: 0x108
No key slot selected, no destination address defined, or error during push operation
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW EVENTS_KEYSLOT_ERROR
Value ID
Value
Description
No key slot selected, no destination address defined, or
error during push operation
NotGenerated
0
Event not generated
Generated
1
Event generated
6.8.5.5 INTEN
Address offset: 0x300
Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW KEYSLOT_PUSHED
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Value ID
Value
Description
Enable or disable interrupt for event KEYSLOT_PUSHED
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Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
B
C
Access
Field
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
RW KEYSLOT_REVOKED
Enable or disable interrupt for event KEYSLOT_REVOKED
RW KEYSLOT_ERROR
Enable or disable interrupt for event KEYSLOT_ERROR
Disabled
0
Disable
Enabled
1
Enable
6.8.5.6 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW KEYSLOT_PUSHED
B
C
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to enable interrupt for event KEYSLOT_PUSHED
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW KEYSLOT_REVOKED
Write '1' to enable interrupt for event KEYSLOT_REVOKED
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW KEYSLOT_ERROR
Write '1' to enable interrupt for event KEYSLOT_ERROR
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.8.5.7 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW KEYSLOT_PUSHED
B
C
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to disable interrupt for event KEYSLOT_PUSHED
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW KEYSLOT_REVOKED
Write '1' to disable interrupt for event KEYSLOT_REVOKED
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW KEYSLOT_ERROR
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Write '1' to disable interrupt for event KEYSLOT_ERROR
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Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.8.5.8 INTPEND
Address offset: 0x30C
Pending interrupts
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
KEYSLOT_PUSHED
Read pending status of interrupt for event
KEYSLOT_PUSHED
B
R
NotPending
0
Read: Not pending
Pending
1
Read: Pending
KEYSLOT_REVOKED
Read pending status of interrupt for event
KEYSLOT_REVOKED
C
R
NotPending
0
Read: Not pending
Pending
1
Read: Pending
NotPending
0
Read: Not pending
Pending
1
Read: Pending
KEYSLOT_ERROR
Read pending status of interrupt for event KEYSLOT_ERROR
6.8.5.9 STATUS
Address offset: 0x40C
Status bits for KMU operation
This register is reset and re-written by the KMU whenever SELECTKEYSLOT is written
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
R
B
R
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
No key slot ID selected by KMU
Enabled
1
Key slot ID successfully selected by KMU
Disabled
0
No access violation detected
Enabled
1
Access violation detected and blocked
SELECTED
Key slot ID successfully selected by the KMU
BLOCKED
Violation status
6.8.5.10 SELECTKEYSLOT
Address offset: 0x500
Select key slot to be read over AHB or pushed over secure APB when TASKS_PUSH_KEYSLOT is started
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW ID
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Select key slot ID to be read over AHB, or pushed over
secure APB, when TASKS_PUSH_KEYSLOT is started.
NOTE: ID=0 is not a valid key slot ID. The 0 ID should be
used when the KMU is idle or not in use.
NOTE: Index N in UICR->KEYSLOT.KEY[N] and UICR>KEYSLOT.CONFIG[N] corresponds to KMU key slot ID=N+1.
6.9 PDM — Pulse density modulation interface
The pulse density modulation (PDM) module enables input of pulse density modulated signals from
external audio frontends, for example, digital microphones. The PDM module generates the PDM clock
and supports single-channel or dual-channel (Left and Right) data input. Data is transferred directly to
RAM buffers using EasyDMA.
Listed here are the main features for PDM:
•
•
•
•
•
Up to two PDM microphones configured as a Left/Right pair using the same data input
16 kHz output sample rate, 16-bit samples
EasyDMA support for sample buffering
HW decimation filters
Selectable ratio of 64 or 80 between PDM_CLK and output sample rate
The PDM module illustrated in PDM module on page 149 is interfacing up to two digital microphones
with the PDM interface. It implements EasyDMA, which relieves real-time requirements associated with
controlling the PDM slave from a low priority CPU execution context. It also includes all the necessary
digital filter elements to produce PCM samples. The PDM module allows continuous audio streaming.
CLK
Band-pass and
Decimation (left)
PDM to PCM
Band-pass and
Decimation (right)
RAM
PDM to PCM
EasyDMA
Sampling
DIN
Master clock
generator
Figure 35: PDM module
6.9.1 Master clock generator
The FREQ field in the master clock's PDMCLKCTRL register allows adjusting the PDM clock's frequency.
The master clock generator does not add any jitter to the HFCLK source chosen. It is recommended (but
not mandatory) to use the Xtal as HFCLK source.
6.9.2 Module operation
By default, bits from the left PDM microphone are sampled on PDM_CLK falling edge, bits for the right are
sampled on the rising edge of PDM_CLK, resulting in two bitstreams. Each bitstream is fed into a digital
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filter which converts the PDM stream into 16-bit PCM samples, and filters and down-samples them to
reach the appropriate sample rate.
The EDGE field in the MODE register allows swapping Left and Right, so that Left will be sampled on rising
edge, and Right on falling.
The PDM module uses EasyDMA to store the samples coming out from the filters into one buffer in RAM.
Depending on the mode chosen in the OPERATION field in the MODE register, memory either contains
alternating left and right 16-bit samples (Stereo), or only left 16-bit samples (Mono).
To ensure continuous PDM sampling, it is up to the application to update the EasyDMA destination
address pointer as the previous buffer is filled.
The continuous transfer can be started or stopped by sending the START and STOP tasks. STOP becomes
effective after the current frame has finished transferring, which will generate the STOPPED event. The
STOPPED event indicates that all activity in the module are finished, and that the data is available in RAM
(EasyDMA has finished transferring as well). Attempting to restart before receiving the STOPPED event
may result in unpredictable behaviour.
6.9.3 Decimation filter
In order to convert the incoming data stream into PCM audio samples, a decimation filter is included in
the PDM interface module.
The input of the filter is the two-channel PDM serial stream (with left channel on clock high, right channel
on clock low). Depending on the RATIO selected, its output is 2 × 16-bit PCM samples at a sample rate
either 64 times or 80 times (depending on the RATIO register) lower than the PDM clock rate.
The filter stage of each channel is followed by a digital volume control, to attenuate or amplify the output
samples in a range of -20 dB to +20 dB around the default (reset) setting, defined by GPDM,default. The gain
is controlled by the GAINL and GAINR registers.
As an example, if the goal is to achieve 2500 RMS output samples (16 bit) with a 1 kHz 90 dBA signal
into a -26 dBFS sensitivity PDM microphone, the user will have to sum the PDM module's default gain
( GPDM,default ) and the gain introduced by the microphone and acoustic path of his implementation (an
attenuation would translate into a negative gain), and adjust GAINL and GAINR by this amount. Assuming
that only the PDM module influences the gain, GAINL and GAINR must be set to -GPDM,default dB to achieve
the requirement.
With GPDM,default=3.2 dB, and as GAINL and GAINR are expressed in 0.5 dB steps, the closest value to
program would be 3.0 dB, which can be calculated as:
GAINL = GAINR = (DefaultGain - (2 * 3))
Remember to check that the resulting values programmed into GAINL and GAINR fall within MinGain and
MaxGain.
6.9.4 EasyDMA
Samples will be written directly to RAM, and EasyDMA must be configured accordingly.
The address pointer for the EasyDMA channel is set in SAMPLE.PTR register. If the destination address set
in SAMPLE.PTR is not pointing to the Data RAM region, an EasyDMA transfer may result in a HardFault or
RAM corruption. See Memory on page 20 for more information about the different memory regions.
DMA supports Stereo (Left+Right 16-bit samples) and Mono (Left only) data transfer, depending on setting
in the OPERATION field in the MODE register. The samples are stored little endian.
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MODE.OPERATION
Bits per sample
Stereo
32 (2x16)
Mono
16
Result stored per RAM
Physical RAM allocated
Result boundary indexes Note
word
(32 bit words)
in RAM
L+R
ceil(SAMPLE.MAXCNT/2) R0=[31:16]; L0=[15:0]
2xL
ceil(SAMPLE.MAXCNT/2) L1=[31:16]; L0=[15:0]
Default
Table 53: DMA sample storage
The destination buffer in RAM consists of one block, the size of which is set in SAMPLE.MAXCNT register.
Format is number of 16-bit samples. The physical RAM allocated is always:
(RAM allocation, in bytes) = SAMPLE.MAXCNT * 2;
(but the mapping of the samples depends on MODE.OPERATION.
If OPERATION=Stereo, RAM will contain a succession of Left and Right samples.
If OPERATION=Mono, RAM will contain a succession of mono samples.
For a given value of SAMPLE.MAXCNT, the buffer in RAM can contain half the stereo sampling time as
compared to the mono sampling time.
The PDM acquisition can be started by the START task, after the SAMPLE.PTR and SAMPLE.MAXCNT
registers have been written. When starting the module, it will take some time for the filters to start
outputting valid data. Transients from the PDM microphone itself may also occur. The first few samples
(typically around 50) might hence contain invalid values or transients. It is therefore advised to discard the
first few samples after a PDM start.
As soon as the STARTED event is received, the firmware can write the next SAMPLE.PTR value (this register
is double-buffered), to ensure continuous operation.
When the buffer in RAM is filled with samples, an END event is triggered. The firmware can start
processing the data in the buffer. Meanwhile, the PDM module starts acquiring data into the new buffer
pointed to by SAMPLE.PTR, and sends a new STARTED event, so that the firmware can update SAMPLE.PTR
to the next buffer address.
6.9.5 Hardware example
Connect the microphone clock to CLK, and data to DIN.
Vdd
L/R
nRFxxxxx
CLK
CLK
DATA
DIN
CLK
DIN
Figure 36: Example of a single PDM microphone, wired as left
Vdd
L/R
nRFxxxxx
CLK
CLK
DATA
DIN
CLK
DIN
Figure 37: Example of a single PDM microphone, wired as right
Note that in a single-microphone (mono) configuration, depending on the microphone’s implementation,
either the left or the right channel (sampled at falling or rising CLK edge respectively) will contain reliable
data. If two microphones are used, one of them has to be set as left, the other as right (L/R pin tied high or
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to GND on the respective microphone). It is strongly recommended to use two microphones of exactly the
same brand and type so that their timings in left and right operation match.
Vdd
L/R
nRFxxxxx
CLK
CLK
DATA
DIN
Vdd
CLK
L/R
DATA
CLK
DIN
Figure 38: Example of two PDM microphones
6.9.6 Pin configuration
The CLK and DIN signals associated to the PDM module are mapped to physical pins according to the
configuration specified in the PSEL.CLK and PSEL.DIN registers respectively. If the CONNECT field in any
PSEL register is set to Disconnected, the associated PDM module signal will not be connected to the
required physical pins, and will not operate properly.
The PSEL.CLK and PSEL.DIN registers and their configurations are only used as long as the PDM module is
enabled, and retained only as long as the device is in System ON mode. See POWER — Power control on
page 59 for more information about power modes. When the peripheral is disabled, the pins will behave
as regular GPIOs, and use the configuration in their respective OUT bit field and PIN_CNF[n] register.
To ensure correct behaviour in the PDM module, the pins used by the PDM module must be configured
in the GPIO peripheral as described in GPIO configuration before enabling peripheral on page 152
before enabling the PDM module. This is to ensure that the pins used by the PDM module are driven
correctly if the PDM module itself is temporarily disabled or the device temporarily enters System OFF.
This configuration must be retained in the GPIO for the selected I/Os as long as the PDM module is
supposed to be connected to an external PDM circuit.
Only one peripheral can be assigned to drive a particular GPIO pin at a time. Failing to do so may result in
unpredictable behaviour.
PDM signal
PDM pin
Direction
Output value
CLK
As specified in PSEL.CLK
Output
0
DIN
As specified in PSEL.DIN
Input
Not applicable
Comment
Table 54: GPIO configuration before enabling peripheral
6.9.7 Registers
Base address Peripheral
Instance
0x50026000
PDM : S
0x40026000
PDM
PDM : NS
Secure mapping
US
DMA security
Description
Pulse density modulation
SA
(digital microphone) interface
Table 55: Instances
Register
Offset
TASKS_START
0x000
Starts continuous PDM transfer
TASKS_STOP
0x004
Stops PDM transfer
SUBSCRIBE_START
0x080
Subscribe configuration for task START
SUBSCRIBE_STOP
0x084
Subscribe configuration for task STOP
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Security
Description
152
Configuration
Peripherals
Register
Offset
Security
Description
EVENTS_STARTED
0x100
PDM transfer has started
EVENTS_STOPPED
0x104
PDM transfer has finished
EVENTS_END
0x108
The PDM has written the last sample specified by SAMPLE.MAXCNT (or the last
sample after a STOP task has been received) to Data RAM
PUBLISH_STARTED
0x180
Publish configuration for event STARTED
PUBLISH_STOPPED
0x184
Publish configuration for event STOPPED
PUBLISH_END
0x188
Publish configuration for event END
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
ENABLE
0x500
PDM module enable register
PDMCLKCTRL
0x504
PDM clock generator control
MODE
0x508
Defines the routing of the connected PDM microphones' signals
GAINL
0x518
Left output gain adjustment
GAINR
0x51C
Right output gain adjustment
RATIO
0x520
Selects the ratio between PDM_CLK and output sample rate. Change PDMCLKCTRL
PSEL.CLK
0x540
Pin number configuration for PDM CLK signal
PSEL.DIN
0x544
Pin number configuration for PDM DIN signal
SAMPLE.PTR
0x560
RAM address pointer to write samples to with EasyDMA
SAMPLE.MAXCNT
0x564
Number of samples to allocate memory for in EasyDMA mode
accordingly.
Table 56: Register overview
6.9.7.1 TASKS_START
Address offset: 0x000
Starts continuous PDM transfer
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_START
Starts continuous PDM transfer
Trigger task
6.9.7.2 TASKS_STOP
Address offset: 0x004
Stops PDM transfer
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Trigger
1
Description
TASKS_STOP
Stops PDM transfer
Trigger task
6.9.7.3 SUBSCRIBE_START
Address offset: 0x080
Subscribe configuration for task START
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Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task START will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.9.7.4 SUBSCRIBE_STOP
Address offset: 0x084
Subscribe configuration for task STOP
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task STOP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.9.7.5 EVENTS_STARTED
Address offset: 0x100
PDM transfer has started
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_STARTED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
PDM transfer has started
6.9.7.6 EVENTS_STOPPED
Address offset: 0x104
PDM transfer has finished
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_STOPPED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
NotGenerated
0
Event not generated
Generated
1
Event generated
PDM transfer has finished
6.9.7.7 EVENTS_END
Address offset: 0x108
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The PDM has written the last sample specified by SAMPLE.MAXCNT (or the last sample after a STOP task
has been received) to Data RAM
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_END
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
The PDM has written the last sample specified by
SAMPLE.MAXCNT (or the last sample after a STOP task has
been received) to Data RAM
NotGenerated
0
Event not generated
Generated
1
Event generated
6.9.7.8 PUBLISH_STARTED
Address offset: 0x180
Publish configuration for event STARTED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event STARTED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.9.7.9 PUBLISH_STOPPED
Address offset: 0x184
Publish configuration for event STOPPED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event STOPPED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.9.7.10 PUBLISH_END
Address offset: 0x188
Publish configuration for event END
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Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event END will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.9.7.11 INTEN
Address offset: 0x300
Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW STARTED
B
C
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Enable or disable interrupt for event STARTED
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
RW STOPPED
Enable or disable interrupt for event STOPPED
RW END
Enable or disable interrupt for event END
6.9.7.12 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW STARTED
B
C
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to enable interrupt for event STARTED
RW STOPPED
Write '1' to enable interrupt for event STOPPED
RW END
Write '1' to enable interrupt for event END
6.9.7.13 INTENCLR
Address offset: 0x308
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Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
C B A
Reset 0x00000000
ID
Access
Field
A
RW STARTED
B
C
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Write '1' to disable interrupt for event STARTED
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW STOPPED
Write '1' to disable interrupt for event STOPPED
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
RW END
Write '1' to disable interrupt for event END
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
6.9.7.14 ENABLE
Address offset: 0x500
PDM module enable register
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW ENABLE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Enable or disable PDM module
6.9.7.15 PDMCLKCTRL
Address offset: 0x504
PDM clock generator control
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x08400000
ID
Access
Field
A
RW FREQ
0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
1000K
0x08000000
PDM_CLK = 32 MHz / 32 = 1.000 MHz
Default
0x08400000
PDM_CLK = 32 MHz / 31 = 1.032 MHz. Nominal clock for
PDM_CLK frequency
RATIO=Ratio64.
1067K
0x08800000
PDM_CLK = 32 MHz / 30 = 1.067 MHz
1231K
0x09800000
PDM_CLK = 32 MHz / 26 = 1.231 MHz
1280K
0x0A000000
PDM_CLK = 32 MHz / 25 = 1.280 MHz. Nominal clock for
RATIO=Ratio80.
1333K
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0x0A800000
PDM_CLK = 32 MHz / 24 = 1.333 MHz
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6.9.7.16 MODE
Address offset: 0x508
Defines the routing of the connected PDM microphones' signals
Bit number
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 6 5 4 3 2 1 0
ID
B A
Reset 0x00000000
ID
Access
Field
A
RW OPERATION
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Stereo
0
Mono
1
Description
Mono or stereo operation
Sample and store one pair (Left + Right) of 16bit samples
per RAM word R=[31:16]; L=[15:0]
Sample and store two successive Left samples (16 bit each)
per RAM word L1=[31:16]; L0=[15:0]
B
RW EDGE
Defines on which PDM_CLK edge Left (or mono) is sampled
LeftFalling
0
Left (or mono) is sampled on falling edge of PDM_CLK
LeftRising
1
Left (or mono) is sampled on rising edge of PDM_CLK
6.9.7.17 GAINL
Address offset: 0x518
Left output gain adjustment
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A
Reset 0x00000028
ID
Access
Field
A
RW GAINL
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0
Value ID
Value
Description
Left output gain adjustment, in 0.5 dB steps, around the
default module gain (see electrical parameters)
0x00 -20 dB gain adjust
0x01 -19.5 dB gain adjust
(...)
0x27 -0.5 dB gain adjust
0x28 0 dB gain adjust
0x29 +0.5 dB gain adjust
(...)
0x4F +19.5 dB gain adjust
0x50 +20 dB gain adjust
MinGain
0x00
-20dB gain adjustment (minimum)
DefaultGain
0x28
0dB gain adjustment
MaxGain
0x50
+20dB gain adjustment (maximum)
6.9.7.18 GAINR
Address offset: 0x51C
Right output gain adjustment
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A
Reset 0x00000028
ID
Access
Field
A
RW GAINR
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0
Value ID
Value
Description
Right output gain adjustment, in 0.5 dB steps, around the
default module gain (see electrical parameters)
MinGain
0x00
-20dB gain adjustment (minimum)
DefaultGain
0x28
0dB gain adjustment
MaxGain
0x50
+20dB gain adjustment (maximum)
6.9.7.19 RATIO
Address offset: 0x520
Selects the ratio between PDM_CLK and output sample rate. Change PDMCLKCTRL accordingly.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW RATIO
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Ratio64
0
Ratio of 64
Ratio80
1
Ratio of 80
Selects the ratio between PDM_CLK and output sample rate
6.9.7.20 PSEL.CLK
Address offset: 0x540
Pin number configuration for PDM CLK signal
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
ID
Access
Field
A
RW PIN
C
RW CONNECT
A A A A A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.9.7.21 PSEL.DIN
Address offset: 0x544
Pin number configuration for PDM DIN signal
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ID
Access
Field
A
RW PIN
C
RW CONNECT
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Value ID
A A A A A
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
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6.9.7.22 SAMPLE.PTR
Address offset: 0x560
RAM address pointer to write samples to with EasyDMA
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW SAMPLEPTR
Value ID
Value
Description
Address to write PDM samples to over DMA
Note: See the memory chapter for details about
which memories are available for EasyDMA.
6.9.7.23 SAMPLE.MAXCNT
Address offset: 0x564
Number of samples to allocate memory for in EasyDMA mode
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW BUFFSIZE
Value ID
Value
Description
[0..32767]
Length of DMA RAM allocation in number of samples
6.9.8 Electrical specification
6.9.8.1 PDM Electrical Specification
Symbol
Description
fPDM,CLK,64
PDM clock speed. PDMCLKCTRL = Default (Setting needed
Min.
Typ.
Max.
1.032
Units
MHz
for 16MHz sample frequency @ RATIO = Ratio64)
fPDM,CLK,80
PDM clock speed. PDMCLKCTRL = 1280K (Setting needed for
..
..
..
MHz
20
ns
16MHz sample frequency @ RATIO = Ratio80)
tPDM,JITTER
Jitter in PDM clock output
TdPDM,CLK
PDM clock duty cycle
60
%
tPDM,DATA
Decimation filter delay
5
ms
tPDM,cv
Allowed clock edge to data valid
125
ns
tPDM,ci
Allowed (other) clock edge to data invalid
0
ns
tPDM,s
Data setup time at fPDM,CLK=1.024 MHz or 1.280 MHz
65
ns
tPDM,h
Data hold time at fPDM,CLK=1.024 MHz or 1.280 MHz
0
GPDM,default
Default (reset) absolute gain of the PDM module
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40
50
ns
3.2
160
dB
Peripherals
tPDM,CLK
CLK
tPDM,cv
tPDM,s
tPDM,h=tPDM,ci
DIN (L)
tPDM,cv
tPDM,s tPDM,h=tPDM,ci
DIN(R)
Figure 39: PDM timing diagram
6.10 PWM — Pulse width modulation
The pulse with modulation (PWM) module enables the generation of pulse width modulated signals
on GPIO. The module implements an up or up-and-down counter with four PWM channels that drive
assigned GPIOs.
The following are the main features of a PWM module:
•
•
•
•
•
Programmable PWM frequency
Up to four PWM channels with individual polarity and duty cycle values
Edge or center-aligned pulses across PWM channels
Multiple duty cycle arrays (sequences) defined in RAM
Autonomous and glitch-free update of duty cycle values directly from memory through EasyDMA (no
CPU involvement)
• Change of polarity, duty cycle, and base frequency possibly on every PWM period
• RAM sequences can be repeated or connected into loops
Sequence 0
DATA RAM
STARTED
STOPPED
EasyDMA
START
Sequence 1
PWM
STOP
SEQSTART[0]
SEQSTART[1]
SEQ[n].REFRESH
SEQSTARTED[0]
SEQSTARTED[1]
SEQEND[0]
SEQEND[1]
Decoder
NEXTSTEP
Carry/Reload
COMP0
PSEL.OUT[0]
COMP1
PSEL.OUT[1]
COMP2
PSEL.OUT[2]
COMP3
PSEL.OUT[3]
Wave Counter
PWM_CLK
COUNTERTOP
PRESCALER
Figure 40: PWM module
6.10.1 Wave counter
The wave counter is responsible for generating the pulses at a duty cycle that depends on the compare
values, and at a frequency that depends on COUNTERTOP.
There is one common 15-bit counter with four compare channels. Thus, all four channels will share the
same period (PWM frequency), but can have individual duty cycle and polarity. The polarity is set by a
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value read from RAM (see figure Decoder memory access modes on page 165). Whether the counter
counts up, or up and down, is controlled by the MODE register.
The timer top value is controlled by the COUNTERTOP register. This register value, in conjunction with the
selected PRESCALER of the PWM_CLK, will result in a given PWM period. A COUNTERTOP value smaller
than the compare setting will result in a state where no PWM edges are generated. OUT[n] is held high,
given that the polarity is set to FallingEdge. All compare registers are internal and can only be configured
through decoder presented later. COUNTERTOP can be safely written at any time.
Sampling follows the START task. If DECODER.LOAD=WaveForm, the register value is ignored and taken
from RAM instead (see section Decoder with EasyDMA on page 165 for more details). If DECODER.LOAD
is anything else than the WaveForm, it is sampled following a STARTSEQ[n] task and when loading a new
value from RAM during a sequence playback.
The following figure shows the counter operating in up mode (MODE=PWM_MODE_Up), with three PWM
channels with the same frequency but different duty cycle:
COUNTERTOP
COMP1
COMP0
OUT[0]
OUT[1]
Figure 41: PWM counter in up mode example - FallingEdge polarity
The counter is automatically reset to zero when COUNTERTOP is reached and OUT[n] will invert. OUT[n]
is held low if the compare value is 0 and held high if set to COUNTERTOP, given that the polarity is set to
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FallingEdge. Counter running in up mode results in pulse widths that are edge-aligned. The following is the
code for the counter in up mode example:
uint16_t pwm_seq[4] = {PWM_CH0_DUTY, PWM_CH1_DUTY, PWM_CH2_DUTY, PWM_CH3_DUTY};
NRF_PWM0->PSEL.OUT[0] = (first_pin PSEL.OUT[0] = (first_pin PSEL.OUT[0] = (first_pin DECODER
= (PWM_LOOP_CNT_Disabled SEQ[0].PTR
= (PWM_DECODER_LOAD_Common SEQ[0].CNT
(PWM_DECODER_MODE_RefreshCount TASKS_SEQSTART[0] = 1;
To completely stop the PWM generation and force the associated pins to a defined state, a STOP task can
be triggered at any time. A STOPPED event is generated when the PWM generation has stopped at the
end of currently running PWM period, and the pins go into their idle state as defined in GPIO OUT register.
PWM generation can then only be restarted through a SEQSTART[n] task. SEQSTART[n] will resume PWM
generation after having loaded the first value from the RAM buffer defined in the SEQ[n].PTR register.
The table below indicates when specific registers get sampled by the hardware. Care should be taken
when updating these registers to avoid that values are applied earlier than expected.
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Register
Taken into account by hardware
Recommended (safe) update
SEQ[n].PTR
When sending the SEQSTART[n] task
After having received the SEQSTARTED[n] event
SEQ[n].CNT
When sending the SEQSTART[n] task
After having received the SEQSTARTED[n] event
SEQ[0].ENDDELAY
When sending the SEQSTART[0] task
Before starting sequence [0] through a SEQSTART[0] task
Every time a new value from sequence [0] has been loaded from
When no more value from sequence [0] gets loaded from RAM
RAM and gets applied to the Wave Counter (indicated by the
(indicated by the SEQEND[0] event)
PWMPERIODEND event)
At any time during sequence [1] (which starts when the
SEQSTARTED[1] event is generated)
SEQ[1].ENDDELAY
When sending the SEQSTART[1] task
Before starting sequence [1] through a SEQSTART[1] task
Every time a new value from sequence [1] has been loaded from
When no more value from sequence [1] gets loaded from RAM
RAM and gets applied to the Wave Counter (indicated by the
(indicated by the SEQEND[1] event)
PWMPERIODEND event)
At any time during sequence [0] (which starts when the
SEQSTARTED[0] event is generated)
SEQ[0].REFRESH
When sending the SEQSTART[0] task
Before starting sequence [0] through a SEQSTART[0] task
Every time a new value from sequence [0] has been loaded from
At any time during sequence [1] (which starts when the
RAM and gets applied to the Wave Counter (indicated by the
SEQSTARTED[1] event is generated)
PWMPERIODEND event)
SEQ[1].REFRESH
When sending the SEQSTART[1] task
Before starting sequence [1] through a SEQSTART[1] task
Every time a new value from sequence [1] has been loaded from
At any time during sequence [0] (which starts when the
RAM and gets applied to the Wave Counter (indicated by the
SEQSTARTED[0] event is generated)
PWMPERIODEND event)
COUNTERTOP
MODE
In DECODER.LOAD=WaveForm: this register is ignored.
Before starting PWM generation through a SEQSTART[n] task
In all other LOAD modes: at the end of current PWM period
After a STOP task has been triggered, and the STOPPED event has
(indicated by the PWMPERIODEND event)
been received.
Immediately
Before starting PWM generation through a SEQSTART[n] task
After a STOP task has been triggered, and the STOPPED event has
been received.
DECODER
Immediately
Before starting PWM generation through a SEQSTART[n] task
After a STOP task has been triggered, and the STOPPED event has
been received.
PRESCALER
Immediately
Before starting PWM generation through a SEQSTART[n] task
After a STOP task has been triggered, and the STOPPED event has
been received.
LOOP
Immediately
Before starting PWM generation through a SEQSTART[n] task
After a STOP task has been triggered, and the STOPPED event has
been received.
PSEL.OUT[n]
Immediately
Before enabling the PWM instance through the ENABLE register
Table 57: When to safely update PWM registers
Note: SEQ[n].REFRESH and SEQ[n].ENDDELAY are ignored at the end of a complex sequence,
indicated by a LOOPSDONE event. The reason for this is that the last value loaded from RAM
is maintained until further action from software (restarting a new sequence, or stopping PWM
generation).
A more complex example, where LOOP.CNT>0, is shown in the following figure:
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SEQ[0].CNT=2, SEQ[1].CNT=3, SEQ[0].REFRESH=1, SEQ[1].REFRESH=0, SEQ[0].ENDDELAY=1, SEQ[1].ENDDELAY=0, LOOP.CNT=1
SEQ[0].PTR
P
O COMPARE
L
PWM clock period
Event/Tasks
SEQSTART[0]
P
O COMPARE
L
(continued below)
SEQSTARTED[0]
SEQEND[0]
SEQ[1].PTR
1 PWM period
SEQ[0].ENDDELAY=1
(continuation)
P
O COMPARE
L
P
O COMPARE
L
PWM generation maintains
last played value
Event/Tasks
SEQSTARTED[1]
SEQEND[1]
LOOPSDONE
Figure 45: Example using two sequences
In this case, an automated playback takes place, consisting of SEQ[0], delay 0, SEQ[1], delay 1, then again
SEQ[0], etc. The user can choose to start a complex playback with SEQ[0] or SEQ[1] through sending the
SEQSTART[0] or SEQSTART[1] task. The complex playback always ends with delay 1.
The two sequences 0 and 1 are defined by the addresses of value tables in RAM (pointed to by
SEQ[n].PTR) and the buffer size (SEQ[n].CNT). The rate at which a new value is loaded is defined
individually for each sequence by SEQ[n].REFRESH. The chaining of sequence 1 following the sequence 0 is
implicit, the LOOP.CNT register allows the chaining of sequence 1 to sequence 0 for a determined number
of times. In other words, it allows to repeat a complex sequence a number of times in a fully automated
way.
In the following code example, sequence 0 is defined with SEQ[0].REFRESH set to 1, meaning that a
new PWM duty cycle is pushed every second PWM period. This complex sequence is started with the
SEQSTART[0] task, so SEQ[0] is played first. Since SEQ[0].ENDDELAY=1 there will be one PWM period delay
between last period on sequence 0 and the first period on sequence 1. Since SEQ[1].ENDDELAY=0 there
is no delay 1, so SEQ[0] would be started immediately after the end of SEQ[1]. However, as LOOP.CNT is
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Peripherals
1, the playback stops after having played SEQ[1] only once, and both SEQEND[1] and LOOPSDONE are
generated (their order is not guaranteed in this case).
NRF_PWM0->PSEL.OUT[0] = (first_pin DECODER
= (1 SEQ[0].PTR
= (PWM_DECODER_LOAD_Common SEQ[0].CNT
(PWM_DECODER_MODE_RefreshCount SEQ[1].PTR
NRF_PWM0->SEQ[1].CNT
= ((uint32_t)(seq1_ram) SEQ[1].ENDDELAY = 0;
NRF_PWM0->TASKS_SEQSTART[0] = 1;
The decoder can also be configured to asynchronously load new PWM duty cycle. If the DECODER.MODE
register is set to NextStep, then the NEXTSTEP task will cause an update of internal compare registers on
the next PWM period.
The following figures provide an overview of each part of an arbitrary sequence, in various modes
(LOOP.CNT=0 and LOOP.CNT>0). In particular, the following are represented:
•
•
•
•
•
Initial and final duty cycle on the PWM output(s)
Chaining of SEQ[0] and SEQ[1] if LOOP.CNT>0
Influence of registers on the sequence
Events generated during a sequence
DMA activity (loading of next value and applying it to the output(s))
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Figure 47: Complex sequence (LOOP.CNT>0) starting with SEQ[0]
SEQ[1].ENDDELA
Y
SEQ[1].CNT
SEQ[0].ENDDELA
Y
SEQ[0].CNT
SEQ[1].CNT
(LOOP.CNT - 1) ...
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
EVENTS_LOOPSDONE
EVENTS_SEQEND[0]
EVENTS_SEQSTARTED[0]
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
SEQ[0].ENDDELA
Y
SEQ[0].CNT
SEQ[1].ENDDELA
Y
SEQ[1].CNT
LOOP.CNT
EVENTS_SEQEND[0]
EVENTS_SEQSTARTED[0]
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
SEQ[0].ENDDELA
Y
SEQ[0].CNT
Loop counter
EVENTS_SEQEND[0]
TASKS_SEQSTART[0]
EVENTS_SEQSTARTED[0]
EVENTS_SEQEND[0]
TASKS_SEQSTART[0]
EVENTS_SEQSTARTED[0]
SEQ[0].ENDDELA
Y
SEQ[0].CNT
Peripherals
100% duty cycle
last loaded
duty cycle
maintained
Previously
loaded duty
cycle
New value load
0% duty cycle
Figure 46: Single shot (LOOP.CNT=0)
Note: The single-shot example also applies to SEQ[1]. Only SEQ[0] is represented for simplicity.
1
100% duty cycle
Previously
loaded duty
cycle
last loaded
duty cycle
maintained
New value load
0% duty cycle
Peripherals
SEQ[1].ENDDELA
Y
SEQ[1].CNT
SEQ[0].ENDDELA
Y
1
SEQ[0].CNT
SEQ[1].CNT
SEQ[0].ENDDELA
Y
(LOOP.CNT - 1) ...
SEQ[0].CNT
SEQ[1].CNT
SEQ[1].ENDDELA
Y
LOOP.CNT
Loop counter
100% duty cycle
Previously
loaded
duty cycle
last loaded
duty cycle
maintained
0% duty cycle
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
EVENTS_LOOPSDONE
EVENTS_SEQEND[0]
EVENTS_SEQSTARTED[0]
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
EVENTS_SEQEND[0]
EVENTS_SEQSTARTED[0]
TASKS_SEQSTART[1]
EVENTS_SEQSTARTED[1]
EVENTS_SEQEND[1]
New value load
Figure 48: Complex sequence (LOOP.CNT>0) starting with SEQ[1]
Note: If a sequence is in use in a simple or complex sequence, it must have a length of SEQ[n].CNT
> 0.
6.10.3 Limitations
Previous compare value is repeated if the PWM period is shorter than the time it takes for the EasyDMA
to retrieve from RAM and update the internal compare registers. This is to ensure a glitch-free operation
even for very short PWM periods.
6.10.4 Pin configuration
The OUT[n] (n=0..3) signals associated with each PWM channel are mapped to physical pins according to
the configuration of PSEL.OUT[n] registers. If PSEL.OUT[n].CONNECT is set to Disconnected, the associated
PWM module signal will not be connected to any physical pins.
The PSEL.OUT[n] registers and their configurations are used as long as the PWM module is enabled and
the PWM generation active (wave counter started). They are retained only as long as the device is in
System ON mode (see section POWER for more information about power modes).
To ensure correct behavior in the PWM module, the pins that are used must be configured in the GPIO
peripheral in the following way before the PWM module is enabled:
PWM signal
PWM pin
Direction
Output value
Comment
OUT[n]
As specified in PSEL.OUT[n]
Output
0
Idle state defined in GPIO OUT
(n=0..3)
register
Table 58: Recommended GPIO configuration before starting PWM generation
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The idle state of a pin is defined by the OUT register in the GPIO module, to ensure that the pins used by
the PWM module are driven correctly. If PWM generation is stopped by triggering a STOP task, the PWM
module itself is temporarily disabled or the device temporarily enters System OFF. This configuration must
be retained in the GPIO for the selected pins (I/Os) for as long as the PWM module is supposed to be
connected to an external PWM circuit.
Only one peripheral can be assigned to drive a particular GPIO pin at a time. Failing to do so may result in
unpredictable behavior.
6.10.5 Registers
Base address Peripheral
Instance
0x50021000
PWM0 : S
0x40021000
0x50022000
0x40022000
0x50023000
0x40023000
0x50024000
0x40024000
PWM
PWM
PWM
PWM
PWM0 : NS
PWM1 : S
PWM1 : NS
PWM2 : S
PWM2 : NS
PWM3 : S
PWM3 : NS
Secure mapping
DMA security
Description
US
SA
Pulse width modulation unit 0
US
SA
Pulse width modulation unit 1
US
SA
Pulse width modulation unit 2
US
SA
Pulse width modulation unit 3
Configuration
Table 59: Instances
Register
Offset
TASKS_STOP
0x004
Security
Description
Stops PWM pulse generation on all channels at the end of current PWM period,
and stops sequence playback
TASKS_SEQSTART[0]
0x008
Loads the first PWM value on all enabled channels from sequence 0, and
starts playing that sequence at the rate defined in SEQ[0]REFRESH and/or
DECODER.MODE. Causes PWM generation to start if not running.
TASKS_SEQSTART[1]
0x00C
Loads the first PWM value on all enabled channels from sequence 1, and
starts playing that sequence at the rate defined in SEQ[1]REFRESH and/or
DECODER.MODE. Causes PWM generation to start if not running.
TASKS_NEXTSTEP
0x010
Steps by one value in the current sequence on all enabled channels if
DECODER.MODE=NextStep. Does not cause PWM generation to start if not
running.
SUBSCRIBE_STOP
0x084
Subscribe configuration for task STOP
SUBSCRIBE_SEQSTART[0]
0x088
Subscribe configuration for task SEQSTART[0]
SUBSCRIBE_SEQSTART[1]
0x08C
Subscribe configuration for task SEQSTART[1]
SUBSCRIBE_NEXTSTEP
0x090
Subscribe configuration for task NEXTSTEP
EVENTS_STOPPED
0x104
Response to STOP task, emitted when PWM pulses are no longer generated
EVENTS_SEQSTARTED[0]
0x108
First PWM period started on sequence 0
EVENTS_SEQSTARTED[1]
0x10C
First PWM period started on sequence 1
EVENTS_SEQEND[0]
0x110
Emitted at end of every sequence 0, when last value from RAM has been applied
EVENTS_SEQEND[1]
0x114
to wave counter
Emitted at end of every sequence 1, when last value from RAM has been applied
to wave counter
EVENTS_PWMPERIODEND 0x118
Emitted at the end of each PWM period
EVENTS_LOOPSDONE
0x11C
Concatenated sequences have been played the amount of times defined in
PUBLISH_STOPPED
0x184
Publish configuration for event STOPPED
PUBLISH_SEQSTARTED[0]
0x188
Publish configuration for event SEQSTARTED[0]
PUBLISH_SEQSTARTED[1]
0x18C
Publish configuration for event SEQSTARTED[1]
PUBLISH_SEQEND[0]
0x190
Publish configuration for event SEQEND[0]
PUBLISH_SEQEND[1]
0x194
Publish configuration for event SEQEND[1]
LOOP.CNT
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Register
Offset
Security
Description
PUBLISH_PWMPERIODEND 0x198
Publish configuration for event PWMPERIODEND
PUBLISH_LOOPSDONE
0x19C
Publish configuration for event LOOPSDONE
SHORTS
0x200
Shortcuts between local events and tasks
INTEN
0x300
Enable or disable interrupt
INTENSET
0x304
Enable interrupt
INTENCLR
0x308
Disable interrupt
ENABLE
0x500
PWM module enable register
MODE
0x504
Selects operating mode of the wave counter
COUNTERTOP
0x508
Value up to which the pulse generator counter counts
PRESCALER
0x50C
Configuration for PWM_CLK
DECODER
0x510
Configuration of the decoder
LOOP
0x514
Number of playbacks of a loop
SEQ[0].PTR
0x520
Beginning address in RAM of this sequence
SEQ[0].CNT
0x524
Number of values (duty cycles) in this sequence
SEQ[0].REFRESH
0x528
Number of additional PWM periods between samples loaded into compare
register
SEQ[0].ENDDELAY
0x52C
Time added after the sequence
SEQ[1].PTR
0x540
Beginning address in RAM of this sequence
SEQ[1].CNT
0x544
Number of values (duty cycles) in this sequence
SEQ[1].REFRESH
0x548
Number of additional PWM periods between samples loaded into compare
SEQ[1].ENDDELAY
0x54C
Time added after the sequence
PSEL.OUT[0]
0x560
Output pin select for PWM channel 0
PSEL.OUT[1]
0x564
Output pin select for PWM channel 1
PSEL.OUT[2]
0x568
Output pin select for PWM channel 2
PSEL.OUT[3]
0x56C
Output pin select for PWM channel 3
register
Table 60: Register overview
6.10.5.1 TASKS_STOP
Address offset: 0x004
Stops PWM pulse generation on all channels at the end of current PWM period, and stops sequence
playback
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_STOP
Stops PWM pulse generation on all channels at the end of
current PWM period, and stops sequence playback
Trigger
1
Trigger task
6.10.5.2 TASKS_SEQSTART[n] (n=0..1)
Address offset: 0x008 + (n × 0x4)
Loads the first PWM value on all enabled channels from sequence n, and starts playing that sequence
at the rate defined in SEQ[n]REFRESH and/or DECODER.MODE. Causes PWM generation to start if not
running.
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Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_SEQSTART
Loads the first PWM value on all enabled channels from
sequence n, and starts playing that sequence at the rate
defined in SEQ[n]REFRESH and/or DECODER.MODE. Causes
PWM generation to start if not running.
Trigger
1
Trigger task
6.10.5.3 TASKS_NEXTSTEP
Address offset: 0x010
Steps by one value in the current sequence on all enabled channels if DECODER.MODE=NextStep. Does
not cause PWM generation to start if not running.
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
W
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
TASKS_NEXTSTEP
Steps by one value in the current sequence on all enabled
channels if DECODER.MODE=NextStep. Does not cause
PWM generation to start if not running.
Trigger
1
Trigger task
6.10.5.4 SUBSCRIBE_STOP
Address offset: 0x084
Subscribe configuration for task STOP
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task STOP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.10.5.5 SUBSCRIBE_SEQSTART[n] (n=0..1)
Address offset: 0x088 + (n × 0x4)
Subscribe configuration for task SEQSTART[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
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A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that task SEQSTART[n] will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
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Peripherals
6.10.5.6 SUBSCRIBE_NEXTSTEP
Address offset: 0x090
Subscribe configuration for task NEXTSTEP
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that task NEXTSTEP will subscribe to
Disabled
0
Disable subscription
Enabled
1
Enable subscription
6.10.5.7 EVENTS_STOPPED
Address offset: 0x104
Response to STOP task, emitted when PWM pulses are no longer generated
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_STOPPED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Response to STOP task, emitted when PWM pulses are no
longer generated
NotGenerated
0
Event not generated
Generated
1
Event generated
6.10.5.8 EVENTS_SEQSTARTED[n] (n=0..1)
Address offset: 0x108 + (n × 0x4)
First PWM period started on sequence n
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_SEQSTARTED
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
First PWM period started on sequence n
NotGenerated
0
Event not generated
Generated
1
Event generated
6.10.5.9 EVENTS_SEQEND[n] (n=0..1)
Address offset: 0x110 + (n × 0x4)
Emitted at end of every sequence n, when last value from RAM has been applied to wave counter
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Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_SEQEND
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Emitted at end of every sequence n, when last value from
RAM has been applied to wave counter
NotGenerated
0
Event not generated
Generated
1
Event generated
6.10.5.10 EVENTS_PWMPERIODEND
Address offset: 0x118
Emitted at the end of each PWM period
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
Value ID
A
RW EVENTS_PWMPERIODEND
Value
Description
Emitted at the end of each PWM period
NotGenerated
0
Event not generated
Generated
1
Event generated
6.10.5.11 EVENTS_LOOPSDONE
Address offset: 0x11C
Concatenated sequences have been played the amount of times defined in LOOP.CNT
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW EVENTS_LOOPSDONE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Concatenated sequences have been played the amount of
times defined in LOOP.CNT
NotGenerated
0
Event not generated
Generated
1
Event generated
6.10.5.12 PUBLISH_STOPPED
Address offset: 0x184
Publish configuration for event STOPPED
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
4418_1315 v1.0
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event STOPPED will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
177
Peripherals
6.10.5.13 PUBLISH_SEQSTARTED[n] (n=0..1)
Address offset: 0x188 + (n × 0x4)
Publish configuration for event SEQSTARTED[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event SEQSTARTED[n] will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.10.5.14 PUBLISH_SEQEND[n] (n=0..1)
Address offset: 0x190 + (n × 0x4)
Publish configuration for event SEQEND[n]
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event SEQEND[n] will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.10.5.15 PUBLISH_PWMPERIODEND
Address offset: 0x198
Publish configuration for event PWMPERIODEND
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW CHIDX
B
RW EN
A A A A
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
[15..0]
Channel that event PWMPERIODEND will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.10.5.16 PUBLISH_LOOPSDONE
Address offset: 0x19C
Publish configuration for event LOOPSDONE
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Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW CHIDX
B
RW EN
Value ID
A A A A
Value
Description
[15..0]
Channel that event LOOPSDONE will publish to.
Disabled
0
Disable publishing
Enabled
1
Enable publishing
6.10.5.17 SHORTS
Address offset: 0x200
Shortcuts between local events and tasks
Bit number
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 6 5 4 3 2 1 0
ID
E D C B A
Reset 0x00000000
ID
Access
Field
A
RW SEQEND0_STOP
B
C
D
E
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Shortcut between event SEQEND[0] and task STOP
Disabled
0
Disable shortcut
Enabled
1
Enable shortcut
Disabled
0
Disable shortcut
Enabled
1
Enable shortcut
Disabled
0
Disable shortcut
Enabled
1
Enable shortcut
Disabled
0
Disable shortcut
Enabled
1
Enable shortcut
RW SEQEND1_STOP
Shortcut between event SEQEND[1] and task STOP
RW LOOPSDONE_SEQSTART0
Shortcut between event LOOPSDONE and task SEQSTART[0]
RW LOOPSDONE_SEQSTART1
Shortcut between event LOOPSDONE and task SEQSTART[1]
RW LOOPSDONE_STOP
Shortcut between event LOOPSDONE and task STOP
Disabled
0
Disable shortcut
Enabled
1
Enable shortcut
6.10.5.18 INTEN
Address offset: 0x300
Enable or disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B
Reset 0x00000000
ID
Access
Field
B
RW STOPPED
C-D
E-F
G
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Enable or disable interrupt for event STOPPED
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
RW SEQSTARTED[i] (i=0..1)
Enable or disable interrupt for event SEQSTARTED[i]
RW SEQEND[i] (i=0..1)
Enable or disable interrupt for event SEQEND[i]
RW PWMPERIODEND
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Enable or disable interrupt for event PWMPERIODEND
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Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B
Reset 0x00000000
ID
H
Access
Field
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Disabled
0
Disable
Enabled
1
Enable
Disabled
0
Disable
Enabled
1
Enable
RW LOOPSDONE
Enable or disable interrupt for event LOOPSDONE
6.10.5.19 INTENSET
Address offset: 0x304
Enable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B
Reset 0x00000000
ID
Access
Field
B
RW STOPPED
C-D
E-F
G
H
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Set
1
Enable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to enable interrupt for event STOPPED
RW SEQSTARTED[i] (i=0..1)
Write '1' to enable interrupt for event SEQSTARTED[i]
RW SEQEND[i] (i=0..1)
Write '1' to enable interrupt for event SEQEND[i]
RW PWMPERIODEND
Write '1' to enable interrupt for event PWMPERIODEND
RW LOOPSDONE
Write '1' to enable interrupt for event LOOPSDONE
6.10.5.20 INTENCLR
Address offset: 0x308
Disable interrupt
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B
Reset 0x00000000
ID
Access
Field
B
RW STOPPED
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0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event STOPPED
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Peripherals
Bit number
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 6 5 4 3 2 1 0
ID
H G F E D C B
Reset 0x00000000
ID
Access
Field
C-D
RW SEQSTARTED[i] (i=0..1)
E-F
G
H
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Clear
1
Disable
Disabled
0
Read: Disabled
Enabled
1
Read: Enabled
Write '1' to disable interrupt for event SEQSTARTED[i]
RW SEQEND[i] (i=0..1)
Write '1' to disable interrupt for event SEQEND[i]
RW PWMPERIODEND
Write '1' to disable interrupt for event PWMPERIODEND
RW LOOPSDONE
Write '1' to disable interrupt for event LOOPSDONE
6.10.5.21 ENABLE
Address offset: 0x500
PWM module enable register
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW ENABLE
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Enable or disable PWM module
Disabled
0
Disabled
Enabled
1
Enable
6.10.5.22 MODE
Address offset: 0x504
Selects operating mode of the wave counter
Bit number
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 6 5 4 3 2 1 0
ID
A
Reset 0x00000000
ID
Access
Field
A
RW UPDOWN
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Up
0
Up counter, edge-aligned PWM duty cycle
UpAndDown
1
Up and down counter, center-aligned PWM duty cycle
Selects up mode or up-and-down mode for the counter
6.10.5.23 COUNTERTOP
Address offset: 0x508
Value up to which the pulse generator counter counts
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Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A
Reset 0x000003FF
ID
Access
Field
A
RW COUNTERTOP
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
[3..32767]
Value up to which the pulse generator counter counts. This
register is ignored when DECODER.MODE=WaveForm and
only values from RAM are used.
6.10.5.24 PRESCALER
Address offset: 0x50C
Configuration for PWM_CLK
Bit number
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 6 5 4 3 2 1 0
ID
A A A
Reset 0x00000000
ID
Access
Field
A
RW PRESCALER
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
DIV_1
0
Divide by 1 (16 MHz)
DIV_2
1
Divide by 2 (8 MHz)
DIV_4
2
Divide by 4 (4 MHz)
DIV_8
3
Divide by 8 (2 MHz)
DIV_16
4
Divide by 16 (1 MHz)
DIV_32
5
Divide by 32 (500 kHz)
DIV_64
6
Divide by 64 (250 kHz)
DIV_128
7
Divide by 128 (125 kHz)
Prescaler of PWM_CLK
6.10.5.25 DECODER
Address offset: 0x510
Configuration of the decoder
Bit number
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 6 5 4 3 2 1 0
ID
B
Reset 0x00000000
ID
Access
Field
A
RW LOAD
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
How a sequence is read from RAM and spread to the
compare register
Common
0
1st half word (16-bit) used in all PWM channels 0..3
Grouped
1
1st half word (16-bit) used in channel 0..1; 2nd word in
Individual
2
1st half word (16-bit) in ch.0; 2nd in ch.1; ...; 4th in ch.3
WaveForm
3
1st half word (16-bit) in ch.0; 2nd in ch.1; ...; 4th in
channel 2..3
COUNTERTOP
B
RW MODE
Selects source for advancing the active sequence
RefreshCount
0
NextStep
1
SEQ[n].REFRESH is used to determine loading internal
compare registers
NEXTSTEP task causes a new value to be loaded to internal
compare registers
6.10.5.26 LOOP
Address offset: 0x514
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A A
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Peripherals
Number of playbacks of a loop
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW CNT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Number of playbacks of pattern cycles
Disabled
0
Looping disabled (stop at the end of the sequence)
6.10.5.27 SEQ[n].PTR (n=0..1)
Address offset: 0x520 + (n × 0x20)
Beginning address in RAM of this sequence
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ID
Access
Field
A
RW PTR
Value ID
Value
Description
Beginning address in RAM of this sequence
Note: See the memory chapter for details about
which memories are available for EasyDMA.
6.10.5.28 SEQ[n].CNT (n=0..1)
Address offset: 0x524 + (n × 0x20)
Number of values (duty cycles) in this sequence
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW CNT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Disabled
0
Description
Number of values (duty cycles) in this sequence
Sequence is disabled, and shall not be started as it is empty
6.10.5.29 SEQ[n].REFRESH (n=0..1)
Address offset: 0x528 + (n × 0x20)
Number of additional PWM periods between samples loaded into compare register
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000001
ID
Access
Field
A
RW CNT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Value ID
Value
Description
Number of additional PWM periods between samples
loaded into compare register (load every REFRESH.CNT+1
PWM periods)
Continuous
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0
Update every PWM period
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Peripherals
6.10.5.30 SEQ[n].ENDDELAY (n=0..1)
Address offset: 0x52C + (n × 0x20)
Time added after the sequence
Bit number
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 6 5 4 3 2 1 0
ID
A A A A A A A A A A A A A A A A A A A A A A A A
Reset 0x00000000
ID
Access
Field
A
RW CNT
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Value ID
Value
Description
Time added after the sequence in PWM periods
6.10.5.31 PSEL.OUT[n] (n=0..3)
Address offset: 0x560 + (n × 0x4)
Output pin select for PWM channel n
Bit number
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 6 5 4 3 2 1 0
ID
C
Reset 0xFFFFFFFF
ID
Access
Field
A
RW PIN
C
RW CONNECT
A A A A A
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Value ID
Value
Description
[0..31]
Pin number
Connection
Disconnected
1
Disconnect
Connected
0
Connect
6.11 RTC — Real-time counter
The real-time counter (RTC) module provides a generic, low power timer on the low frequency clock
source (LFCLK).
32.768 kHz
RTC
START
PRESCALER
STOP
COUNTER
CLEAR
TRIGOVRFLW
TICK
OVRFLW
CC[0:n]
CAPTURE[0:n]
COMPARE[0:n]
Figure 49: RTC block diagram
The RTC module features a 24-bit COUNTER, a 12-bit (1/X) prescaler, capture/compare registers, and a tick
event generator for low power, tickless RTOS implementation.
6.11.1 Clock source
The RTC will run off the LFCLK.
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When started, the RTC will automatically request the LFCLK source with RC oscillator if the LFCLK is not
already running.
See CLOCK — Clock control on page 65 for more information about clock sources.
6.11.2 Resolution versus overflow and the prescaler
The relationship between the prescaler, counter resolution and overflow is summarized in a table.
Prescaler
Counter resolution
Overflow
0
30.517 μs
512 seconds
28-1
7812.5 μs
131072 seconds
212-1
125 ms
582.542 hours
Table 61: RTC resolution versus overflow
Counter increment frequency is given by the following equation:
fRTC [kHz] = 32.768 / (PRESCALER + 1 )
The PRESCALER register is read/write when the RTC is stopped. Once the RTC is started, the prescaler
register is read-only and thus writing to it when the RTC is started has no effect.
The prescaler is restarted on tasks START, CLEAR and TRIGOVRFLW. That is, the prescaler value is latched to
an internal register () on these tasks.
Examples:
1. Desired COUNTER frequency 100 Hz (10 ms counter period)
PRESCALER = round(32.768 kHz / 100 Hz) - 1 = 327
fRTC = 99.9 Hz
10009.576 μs counter period
2. Desired COUNTER frequency 8 Hz (125 ms counter period)
PRESCALER = round(32.768 kHz / 8 Hz) – 1 = 4095
fRTC = 8 Hz
125 ms counter period
6.11.3 Counter register
The counter increments on LFCLK when the internal PRESCALER register () is 0x00.
is reloaded from the PRESCALER register. If enabled, the TICK event occurs on each increment of the
COUNTER. The TICK event is disabled by default.
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Peripherals
SysClk
LFClk
TICK
PRESC
0x000
COUNTER
0x000
0x000
0x000
0x000
0x000000
0x000001
0x000002
0x000003
Figure 50: Timing diagram - COUNTER_PRESCALER_0
SysClk
LFClk
TICK
PRESC
0x001
0x000
COUNTER
0x001
0x000000
0x000
0x001
0x000001
Figure 51: Timing diagram - COUNTER_PRESCALER_1
6.11.4 Overflow
An OVRFLW event is generated on COUNTER register overflow (overflowing from 0xFFFFFF to 0).
The TRIGOVRFLW task will then set the COUNTER value to 0xFFFFF0, to allow software test of the overflow
condition.
Note: The OVRFLW event is disabled by default.
6.11.5 Tick event
The TICK event enables low power tick-less RTOS implementation, as it optionally provides a regular
interrupt source for an RTOS without the need to use the ARM® SysTick feature.
Using the TICK event, rather than the SysTick, allows the CPU to be powered down while still keeping RTOS
scheduling active.
Note: The TICK event is disabled by default.
6.11.6 Event control
To optimize RTC power consumption, events in the RTC can be individually disabled to prevent PCLK16M
and HFCLK from being requested when those events are triggered. This is managed using the EVTEN
register.
For example, if the TICK event is not required for an application, it should be disabled, since its frequent
occurrences may increase power consumption when HFCLK otherwise could be powered down for long
periods of time.
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Peripherals
This means that the RTC implements a slightly different task and event system compared to the standard
system described in Peripheral interface on page 14. The RTC task and event system is illustrated in the
figure below.
Task signal from PPI
RTC
write
TASK
OR
task
RTC
core
event
EVTEN
m
INTEN
m
EVENT m
IRQ signal to NVIC
Event signal to PPI
Figure 52: Tasks, events and interrupts in the RTC
6.11.7 Compare
The RTC implements one COMPARE event for every available capture/compare register.
When the COUNTER is incremented and then becomes equal to the value specified in the capture
compare register CC[n], the corresponding compare event COMPARE[n] is generated.
When setting a compare register, the following behavior of the RTC COMPARE event should be noted:
• If a CC register value is 0 when a CLEAR task is set, this will not trigger a COMPARE event.
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SysClk
LFClk
PRESC
0x000
COUNTER
X
0x000000
CLEAR
CC[0]
0x000000
COMPARE[0]
0
Figure 53: Timing diagram - COMPARE_CLEAR
• If a CC register is N and the COUNTER value is N when the START task is set, this will not trigger a
COMPARE event.
SysClk
LFClk
PRESC
0x000
COUNTER
N-1
N
N+1
START
CC[0]
N
COMPARE[0]
0
Figure 54: Timing diagram - COMPARE_START
• A COMPARE event occurs when a CC register is N and the COUNTER value transitions from N-1 to N.
SysClk
LFClk
PRESC
COUNTER
0x000
N-2
N-1
CC[0]
COMPARE[0]
N
N+1
N
0
1
Figure 55: Timing diagram - COMPARE
• If the COUNTER is N, writing N+2 to a CC register is guaranteed to trigger a COMPARE event at N+2.
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Peripherals
SysClk
LFClk
PRESC
COUNTER
0x000
N-1
N
N+1
N+2
> 62.5 ns
CC[0]
X
N+2
COMPARE[0]
0
1
Figure 56: Timing diagram - COMPARE_N+2
• If the COUNTER is N, writing N or N+1 to a CC register may not trigger a COMPARE event.
SysClk
LFClk
PRESC
COUNTER
0x000
N-2
N-1
N
N+1
>= 0
CC[0]
X
N+1
COMPARE[0]
0
Figure 57: Timing diagram - COMPARE_N+1
• If the COUNTER is N and the current CC register value is N+1 or N+2 when a new CC value is written, a
match may trigger on the previous CC value before the new value takes effect. If the current CC value
greater than N+2 when the new value is written, there will be no event due to the old value.
SysClk
LFClk
PRESC
COUNTER
CC[0]
0x000
N-2
N-1
N
N+1
>= 0
N
COMPARE[0]
X
0
1
Figure 58: Timing diagram - COMPARE_N-1
6.11.8 Task and event jitter/delay
Jitter or delay in the RTC is due to the peripheral clock being a low frequency clock (LFCLK) which is not
synchronous to the faster PCLK16M.
Registers in the peripheral interface, part of the PCLK16M domain, have a set of mirrored registers in
the LFCLK domain. For example, the COUNTER value accessible from the CPU is in the PCLK16M domain
and is latched on read from an internal COUNTER register in the LFCLK domain. The COUNTER register
is modified each time the RTC ticks. The registers are synchronised between the two clock domains
(PCLK16M and LFCLK).
4418_1315 v1.0
189
Peripherals
1. CLEAR and STOP (and TRIGOVRFLW; not shown) will be delayed as long as it takes for the peripheral to
clock a falling edge and rising of the LFCLK. This is between 15.2585 μs and 45.7755 μs – rounded to 15
μs and 46 μs for the remainder of the section.
SysClk
CLEAR
LFClk
PRESC
COUNTER
CLEARa
0x000
X
X+1
0x000000
0x000001
0 or more SysClk after
= ~15 us
1 or more SysClk before
CLEARb
Figure 59: Timing diagram - DELAY_CLEAR
SysClk
STOP
LFClk
PRESC
COUNTER
STOPa
0x000
X
X+1
0 or more SysClk after
= ~15 us
1 or more SysClk before
STOPb
Figure 60: Timing diagram - DELAY_STOP
2. The START task will start the RTC. Assuming that the LFCLK was previously running and stable, the first
increment of COUNTER (and instance of TICK event) will be typically after 30.5 μs +/-15 μs. In some
cases, in particular if the RTC is started before the LFCLK is running, that timing can be up to ~250 μs.
The software should therefore wait for the first TICK if it has to make sure the RTC is running. Sending
a TRIGOVRFLW task sets the COUNTER to a value close to overflow. However, since the update of
COUNTER relies on a stable LFCLK, sending this task while LFCLK is not running will start LFCLK, but
the update will then be delayed by the same amount of time of up to ~250 µs. The figures show the
smallest and largest delays on the START task, appearing as a +/-15 μs jitter on the first COUNTER
increment.
SysClk
First tick
LFClk
PRESC
COUNTER
START
0x000
X
X+1
X+2
>= ~15 us
0 or more SysClk before
Figure 61: Timing diagram - JITTER_START-
4418_1315 v1.0
190
X+3
Peripherals
SysClk
First tick
LFClk
PRESC
0x000
COUNTER
X
X+1
X+2
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