SWRU626 December   2025 CC3501E , CC3551E

 

  1.   1
  2. 1 Read This First
    1. 1.1 About This Manual
    2. 1.2 Register, Field, and Bit Calls
    3.     Trademarks
  3. 2 Architecture Overview
    1. 2.1  Target Applications
    2. 2.2  Introduction
    3. 2.3  Internal System Diagram
    4. 2.4  Arm Cortex M33
      1. 2.4.1 Processor Core
      2. 2.4.2 SysTick Timer
      3. 2.4.3 Nested Vectored Interrupt Controller
      4. 2.4.4 System Control Block (SCB)
      5. 2.4.5 TI AI instruction extensions
    5. 2.5  Power Management
      1. 2.5.1 VDD_MAIN
      2. 2.5.2 VDD_IO
      3. 2.5.3 VDDSF
      4. 2.5.4 VDD_PA
    6. 2.6  Debug Subsystem (DEBUGSS)
    7. 2.7  Memory Subsystem (MEMSS)
      1. 2.7.1 External Memory Interface
    8. 2.8  Hardware Security Module
    9. 2.9  General Purpose Timers (GPT)
    10. 2.10 Real Time Clock (RTC)
    11. 2.11 Direct Memory Access
    12. 2.12 GPIOs
    13. 2.13 Communication Peripherals
      1. 2.13.1 UART
      2. 2.13.2 I2C
      3. 2.13.3 SPI
      4. 2.13.4 I2S
      5. 2.13.5 SDMMC
      6. 2.13.6 SDIO
      7. 2.13.7 CAN
      8. 2.13.8 ADC
  4. 3  Arm Cortex-M33 Processor
    1. 3.1 Arm Cortex-M33 Processor Introduction
    2. 3.2 Block Diagram
    3. 3.3 M33 instantiation parameters
    4. 3.4 Arm Cortex-M33 System Peripheral Details
      1. 3.4.1 Floating Point Unit (FPU)
      2. 3.4.2 Memory Protection Unit (MPU)
      3. 3.4.3 Digital Signal Processing (DSP)
      4. 3.4.4 Security Attribution Unit (SAU)
      5. 3.4.5 System Timer
      6. 3.4.6 Nested Vectored Interrupt Controller
      7. 3.4.7 System Control Block
      8. 3.4.8 System Control Space
    5. 3.5 CPU Sub-System Peripheral Details
      1. 3.5.1 Trace Port Interface Unit (TPIU)
      2. 3.5.2 DAP Bridge and Debug Authentication
      3. 3.5.3 Implementation Defined Attribution Unit (IDAU)
    6. 3.6 Programming Model
      1. 3.6.1 Modes of operation and execution
        1. 3.6.1.1 Security states
        2. 3.6.1.2 Operating modes
        3. 3.6.1.3 Operating states
        4. 3.6.1.4 Privileged access and unprivileged user access
      2. 3.6.2 Instruction set summary
      3. 3.6.3 Memory model
        1. 3.6.3.1 Private Peripheral Bus
        2. 3.6.3.2 Unaligned accesses
      4. 3.6.4 Processor core registers summary
      5. 3.6.5 Exceptions
        1. 3.6.5.1 Exception handling and prioritization
    7. 3.7 TrustZone-M
      1. 3.7.1 Overview
      2. 3.7.2 M33 Configuration
      3. 3.7.3 Description of elements
        1. 3.7.3.1 IDAU (Implementation Defined Attribution Unit)
          1. 3.7.3.1.1 Expected use
    8. 3.8 CC35xx Host MCU Registers
      1. 3.8.1 HOSTMCU_AON Registers
      2. 3.8.2 HOST_MCU Registers
      3. 3.8.3 HOST_MCU_SEC Registers
    9. 3.9 Arm® Cortex®-M33 Registers
      1. 3.9.1  CPU_ROM_TABLE Registers
      2. 3.9.2  TPIU Registers
      3. 3.9.3  DCB Registers
      4. 3.9.4  DIB Registers
      5. 3.9.5  DWT Registers
      6. 3.9.6  FPB Registers
      7. 3.9.7  FPE Registers
      8. 3.9.8  ICB Registers
      9. 3.9.9  ITM Registers
      10. 3.9.10 MPU Registers
      11. 3.9.11 NVIC Registers
      12. 3.9.12 SAU Registers
      13. 3.9.13 SCB Registers
      14. 3.9.14 SYSTIMER Registers
      15. 3.9.15 SYSTICK Registers
  5. 4 Memory Map
    1. 4.1 Memory Map
  6. 5 Interrupts and Events
    1. 5.1 Exception Model
      1. 5.1.1 Exception States
      2. 5.1.2 Exception Types
      3. 5.1.3 Exception Handlers
      4. 5.1.4 Vector Table
      5. 5.1.5 Exception Priorities
      6. 5.1.6 Interrupt Priority Grouping
      7. 5.1.7 Exception Entry and Return
        1. 5.1.7.1 Exception Entry
        2. 5.1.7.2 Exception Return
    2. 5.2 Fault Handling
      1. 5.2.1 Fault Types
      2. 5.2.2 Fault Escalation to HardFault
      3. 5.2.3 Fault Status Registers and Fault Address Registers
      4. 5.2.4 Lockup
    3. 5.3 Security State Switches
    4. 5.4 Event Manager
      1. 5.4.1 Introduction
      2. 5.4.2 Interrupts List
      3. 5.4.3 Wakeup Sources
      4. 5.4.4 Shared Peripherals MUX Selector
        1. 5.4.4.1 ADC HW Event Selector Mux
        2. 5.4.4.2 I2S HW Event Selector Mux
        3. 5.4.4.3 PDM HW Event Selector Mux
      5. 5.4.5 Timers MUX Selector Mux
        1. 5.4.5.1 SysTimer0 HW Event Selector Mux
        2. 5.4.5.2 SysTimer1 HW Event Selector Mux
        3. 5.4.5.3 RTC HW Event Selector Mux
      6. 5.4.6 GPTIMERs MUX Selector Mux
        1. 5.4.6.1 GPTIMER0 HW Event Selector Mux
        2. 5.4.6.2 GPTIMER1 HW Event Selector Mux
    5. 5.5 SOC_IC Registers
    6. 5.6 SOC_AON Registers
    7. 5.7 SOC_AAON Registers
  7. 6 Debug Subsystem (DEBUGSS)
    1. 6.1 Introduction
    2. 6.2 Block Diagram
    3. 6.3 Overview
    4. 6.4 Physical Interface
    5. 6.5 Debug Access Ports
    6. 6.6 Debug Features
      1. 6.6.1 Processor Debug
      2. 6.6.2 Breakpoint Unit (BPU)
      3. 6.6.3 Peripheral Debug
    7. 6.7 Behavior in Low Power Modes
    8. 6.8 Debug Access Control
    9. 6.9 SOC_DEBUGSS Registers
  8. 7 Power, Reset, Clock Management
    1. 7.1 Power Management
      1. 7.1.1 Power Supply System
        1. 7.1.1.1 VDD_MAIN
        2. 7.1.1.2 VIO
        3. 7.1.1.3 VDDSF
        4. 7.1.1.4 VPA
      2. 7.1.2 Power States
      3. 7.1.3 Power Domains
      4. 7.1.4 Brownout (BOR)
      5. 7.1.5 Boot Sequence
    2. 7.2 Reset
      1. 7.2.1 Reset Cause
      2. 7.2.2 Watchdog Timer (WDT)
    3. 7.3 Clocks
      1. 7.3.1 Fast Clock
      2. 7.3.2 Slow Clock
        1. 7.3.2.1 Slow Clock Overview
        2. 7.3.2.2 Slow Clock Tree
        3. 7.3.2.3 Slow Clock Boot Process
    4. 7.4 PRCM_AON Registers
    5. 7.5 PRCM_SCRATCHPAD Registers
  9. 8 Memory Subsystem (MEMSS)
    1. 8.1  Introduction
    2. 8.2  SRAM
    3. 8.3  D-Cache
    4. 8.4  Flash
    5. 8.5  PSRAM
    6. 8.6  XiP Memory Access
      1. 8.6.1 OTFDE
      2. 8.6.2 xSPI
      3. 8.6.3 Topology
      4. 8.6.4 µDMA
      5. 8.6.5 Arbiter
    7. 8.7  ICACHE Registers
    8. 8.8  DCACHE Registers
    9. 8.9  OSPI Registers
    10. 8.10 HOST_XIP Registers
  10. 9 Hardware Security Module (HSM)
    1. 9.1 Introduction
    2. 9.2 Overview
    3. 9.3 Mailbox and Register Access Firewall
    4. 9.4 DMA Firewall
    5. 9.5 HSM Key Storage
    6. 9.6 HSM Registers
    7. 9.7 HSM_NON_SEC Registers
    8. 9.8 HSM_SEC Registers
  11. 10Device Boot and Bootloader
    1. 10.1 CC35xx Boot Concept
    2. 10.2 Features
    3. 10.3 Vendor Images Format and Processing
      1. 10.3.1 External Flash Arrangement
      2. 10.3.2 Vendor Images Format
    4. 10.4 Boot Flows
      1. 10.4.1 Application Execution Boot Flow
      2. 10.4.2 Activation Flow
      3. 10.4.3 Initial Programming Flow
      4. 10.4.4 Reprogramming Flow
      5. 10.4.5 Wireless Connectivity Testing Tool Flow
    5. 10.5 Chain of Trust
  12. 11Direct Memory Access (DMA)
    1. 11.1 Overview
    2. 11.2 Block Diagram
    3. 11.3 Functional Description
      1. 11.3.1 Channels Assignment
      2. 11.3.2 Transfer Types
      3. 11.3.3 Addressing Modes
      4. 11.3.4 Transfer Modes
      5. 11.3.5 DMA Aligner Support
      6. 11.3.6 Initiating DMA Transfers
      7. 11.3.7 Stopping DMA Transfers
      8. 11.3.8 Channel Priorities
      9. 11.3.9 DMA Interrupts
    4. 11.4 HOST_DMA Registers
  13. 12One Time Programming (OTP)
  14. 13General Purpose Timers (GPT)
    1. 13.1 Overview
    2. 13.2 Block Diagram
    3. 13.3 Functional Description
      1. 13.3.1  Prescaler
      2. 13.3.2  Counter
      3. 13.3.3  Target
      4. 13.3.4  Channel Input Logic
      5. 13.3.5  Channel Output Logic
      6. 13.3.6  Channel Actions
        1. 13.3.6.1 Period and Pulse Width Measurement
        2. 13.3.6.2 Clear on Zero, Toggle on Compare Repeatedly
        3. 13.3.6.3 Set on Zero, Toggle on Compare Repeatedly
      7. 13.3.7  Channel Capture Configuration
      8. 13.3.8  Channel Filters
        1. 13.3.8.1 Setting up the Channel Filters
      9. 13.3.9  Synchronize Multiple GPTimers
      10. 13.3.10 Interrupts, ADC Trigger, and DMA Request
    4. 13.4 Timer Modes
      1. 13.4.1 Quadrature Decoder
      2. 13.4.2 DMA
      3. 13.4.3 IR Generation
      4. 13.4.4 Fault and Park
      5. 13.4.5 Dead-Band
      6. 13.4.6 Dead-Band, Fault and Park
      7. 13.4.7 Example Application: Brushless DC (BLDC) Motor
    5. 13.5 GPTIMER Registers
  15. 14System Timer (SysTimer)
    1. 14.1 Overview
    2. 14.2 Block Diagram
    3. 14.3 Functional Description
      1. 14.3.1 Common Channel Features
        1. 14.3.1.1 Compare Mode
        2. 14.3.1.2 Capture Mode
        3. 14.3.1.3 Additional Channel Arming Methods
      2. 14.3.2 Interrupts and Events
    4. 14.4 SYSRESOURCES Registers
    5. 14.5 SYSTIM Registers
  16. 15Real-Time Clock (RTC)
    1. 15.1 Introduction
    2. 15.2 Block Diagram
    3. 15.3 Interrupts and Events
      1. 15.3.1 Input Event
      2. 15.3.2 Output Event
      3. 15.3.3 Arming and Disarming Channels
    4. 15.4 CAPTURE and COMPARE Configurations
      1. 15.4.1 CHANNEL 0 - COMPARE CHANNEL
      2. 15.4.2 CHANNEL 1 - CAPTURE CHANNEL
    5. 15.5 RTC Registers
  17. 16General Purpose Input/Output (GPIOs)
    1. 16.1 Introduction
    2. 16.2 Block Diagram
    3. 16.3 I/O Mapping and Configuration
      1. 16.3.1 Basic I/O Mapping
      2. 16.3.2 Pin Mapping
    4. 16.4 Edge Detection
    5. 16.5 GPIO
    6. 16.6 I/O Pins
    7. 16.7 Unused Pins
    8. 16.8 IOMUX Registers
  18. 17Universal Asynchronous Receivers/Transmitters (UART)
    1. 17.1 Introduction
    2. 17.2 Block Diagram
    3. 17.3 UART Functional Description
      1. 17.3.1 Transmit and Receive Logic
      2. 17.3.2 Baud Rate Generation
      3. 17.3.3 FIFO Operation
        1. 17.3.3.1 FIFO Remapping
      4. 17.3.4 Data Transmission
      5. 17.3.5 Flow Control
      6. 17.3.6 IrDA Encoding and Decoding
      7. 17.3.7 Interrupts
      8. 17.3.8 Loopback Operation
    4. 17.4 UART-LIN Specification
      1. 17.4.1 Break transmission in UART mode
      2. 17.4.2 Break reception in UART mode
      3. 17.4.3 Break/Synch transmission in LIN mode
      4. 17.4.4 Break/Synch reception in LIN mode
      5. 17.4.5 Dormant mode operation
      6. 17.4.6 Event signal generation
      7. 17.4.7 Event signal detection when device is in active/idle modes
      8. 17.4.8 Event signal detection when device is in sleep mode
    5. 17.5 Interface to Host DMA
    6. 17.6 Initialization and Configuration
    7. 17.7 UART Registers
  19. 18Serial Peripheral Interface (SPI)
    1. 18.1 Overview
      1. 18.1.1 Features
      2. 18.1.2 Block Diagram
    2. 18.2 Signal Description
    3. 18.3 Functional Description
      1. 18.3.1  Clock Control
      2. 18.3.2  FIFO Operation
        1. 18.3.2.1 Transmit FIFO
        2. 18.3.2.2 Repeated Transmit Operation
        3. 18.3.2.3 Receive FIFO
        4. 18.3.2.4 FIFO Flush
      3. 18.3.3  Interrupts
      4. 18.3.4  Data Format
      5. 18.3.5  Delayed Data Sampling
      6. 18.3.6  Chip Select Control
      7. 18.3.7  Command Data Control
      8. 18.3.8  Protocol Descriptions
        1. 18.3.8.1 Motorola SPI Frame Format
        2. 18.3.8.2 Texas Instruments Synchronous Serial Frame Format
        3. 18.3.8.3 MICROWIRE Frame Format
      9. 18.3.9  CRC Configuration
      10. 18.3.10 Auto CRC Functionality
      11. 18.3.11 SPI Status
      12. 18.3.12 Debug Halt
    4. 18.4 Host DMA Operation
    5. 18.5 Initialization and Configuration
    6. 18.6 SPI Registers
  20. 19Inter-Integrated Circuit (I2C) Interface
    1. 19.1 Introduction
    2. 19.2 Block Diagram
    3. 19.3 Functional Description
      1. 19.3.1 Clock Control
        1. 19.3.1.1 Internal Clock
        2. 19.3.1.2 External Clock
      2. 19.3.2 General Architecture
        1. 19.3.2.1  Start and Stop Conditions
        2. 19.3.2.2  Data Format with 7-Bit Address
        3. 19.3.2.3  Data Format with 10-Bit Addressing
          1. 19.3.2.3.1 Additional 10-Bit Scenarios
        4. 19.3.2.4  Acknowledge
        5. 19.3.2.5  Repeated Start
        6. 19.3.2.6  Clock Stretching
        7. 19.3.2.7  Arbitration
        8. 19.3.2.8  Multi-Controller mode
        9. 19.3.2.9  Glitch Suppression
        10. 19.3.2.10 FIFO Operation
        11. 19.3.2.11 Burst Mode Operation
        12. 19.3.2.12 DMA Operation
        13. 19.3.2.13 Flush Stale Tx Data in Target Mode
          1. 19.3.2.13.1 Recommended Sequence
        14. 19.3.2.14 SMBUS 3.0 Support
          1. 19.3.2.14.1 Quick Command
          2. 19.3.2.14.2 Acknowledge Control
          3. 19.3.2.14.3 Alert Response protocol
          4. 19.3.2.14.4 Address Resolution Protocol
          5. 19.3.2.14.5 Enhanced Acknowledge Control
    4. 19.4 Initialization and Configuration
    5. 19.5 Interrupts
    6. 19.6 I2C Registers
  21. 20Secure Digital Multimedia Card (SDMMC)
    1. 20.1 Introduction
      1. 20.1.1 SDMMC Features
      2. 20.1.2 Integration
    2. 20.2 Functional Description
      1. 20.2.1  SDMMC Functional Modes
        1. 20.2.1.1 SDMMC Connected to an SD Card
        2. 20.2.1.2 Protocol and Data Format
          1. 20.2.1.2.1 Protocol
          2. 20.2.1.2.2 Data Format
      2. 20.2.2  SD Card Feedback
      3. 20.2.3  Resets
        1. 20.2.3.1 Hardware Reset
        2. 20.2.3.2 Software Reset
      4. 20.2.4  Interrupt Requests
        1. 20.2.4.1 Interrupt-Driven Operation
        2. 20.2.4.2 Polling
      5. 20.2.5  DMA Modes
        1. 20.2.5.1 DMA Peripheral Mode Operations
          1. 20.2.5.1.1 DMA Receive Mode
          2. 20.2.5.1.2 DMA Transmit Mode
      6. 20.2.6  Buffer Management
        1. 20.2.6.1 Data Buffer
          1. 20.2.6.1.1 Memory Size and Block Length
          2. 20.2.6.1.2 Data Buffer Status
      7. 20.2.7  Transfer Process
        1. 20.2.7.1 Different Types of Commands
        2. 20.2.7.2 Different Types of Responses
      8. 20.2.8  Transfer or Command Status and Error Reporting
        1. 20.2.8.1 Busy Timeout for R1b, R5b Response Type
        2. 20.2.8.2 Busy Timeout After Write CRC Status
        3. 20.2.8.3 Write CRC Status Timeout
        4. 20.2.8.4 Read Data Timeout
      9. 20.2.9  Auto Command 12 Timings
        1. 20.2.9.1 Auto Command 12 Timings During Write Transfer
        2. 20.2.9.2 Auto Command 12 Timings During Read Transfer
      10. 20.2.10 Transfer Stop
      11. 20.2.11 Output Signals Generation
        1. 20.2.11.1 Generation on Falling Edge of SDMMC Clock
        2. 20.2.11.2 Generation on Rising Edge of SDMMC Clock
      12. 20.2.12 Test Registers
      13. 20.2.13 SDMMC Hardware Status Features
    3. 20.3 Low-Level Programming Models
      1. 20.3.1 SDMMC Initialization Flow
        1. 20.3.1.1 Enable OCP and CLKADPI Clocks
        2. 20.3.1.2 SD Soft Reset Flow
        3. 20.3.1.3 Set SD Default Capabilities
        4. 20.3.1.4 SDMMC Host and Bus Configuration
      2. 20.3.2 Operational Modes Configuration
        1. 20.3.2.1 Basic Operations for SDMMC
        2. 20.3.2.2 Card Detection, Identification, and Selection
    4. 20.4 SDMMC Registers
  22. 21Secure Digital Input/Output (SDIO)
    1. 21.1 Introduction
    2. 21.2 Block Diagram
    3. 21.3 Functional Description
      1. 21.3.1 SDIO Interface Description
      2. 21.3.2 Protocol and Data Format
      3. 21.3.3 I/O Read/Write Command
        1. 21.3.3.1 IO_WR_DIRECT Command (CMD52)
        2. 21.3.3.2 IO_WR_EXTENDED Command (CMD53)
      4. 21.3.4 Reset
      5. 21.3.5 FIFO Operation
        1. 21.3.5.1 Rx FIFO (For Host Write)
        2. 21.3.5.2 Tx FIFO (For Host Read)
      6. 21.3.6 Interrupt Request
        1. 21.3.6.1 External Host IRQ
        2. 21.3.6.2 M33 IRQ
      7. 21.3.7 Transaction Details
        1. 21.3.7.1 Host write to SDIO IP (Rx FIFO)
          1. 21.3.7.1.1 Host write to SDIO IP (Rx FIFO) – Long SW latency case
          2. 21.3.7.1.2 Host write to SDIO IP (Rx FIFO) – CRC Error Case
        2. 21.3.7.2 Host reads from SDIO (TX buffer)
    4. 21.4 SDIO_CORE Registers
    5. 21.5 SDIO_CARD_FN1 Registers
  23. 22Inter-Integrated Circuit Sound (I2S)
    1. 22.1  Introduction
    2. 22.2  Block Diagram
    3. 22.3  Signal Descriptions
    4. 22.4  Functional Description
      1. 22.4.1 Pin Configuration
      2. 22.4.2 Serial Format Configuration
        1. 22.4.2.1 Register Configuration
      3. 22.4.3 Left-Justified (LJF)
        1. 22.4.3.1 Register Configuration
      4. 22.4.4 Right-Justified (RJF)
        1. 22.4.4.1 Register Configuration
      5. 22.4.5 DSP
        1. 22.4.5.1 Register Configuration
      6. 22.4.6 Clock Configuration
    5. 22.5  Memory Interface
      1. 22.5.1 Sample Word Length
      2. 22.5.2 Padding Mechanism
      3. 22.5.3 Channel Mapping
      4. 22.5.4 Sample Storage in Memory
      5. 22.5.5 DMA Operation
        1. 22.5.5.1 Start-Up
        2. 22.5.5.2 Operation
        3. 22.5.5.3 Shutdown
    6. 22.6  Samplestamp Generator
      1. 22.6.1 Samplestamp Counters
      2. 22.6.2 Start-Up Triggers
      3. 22.6.3 Samplestamp Capture
      4. 22.6.4 Achieving constant audio latency
    7. 22.7  Error Detection
    8. 22.8  Usage
      1. 22.8.1 Start-Up Sequence
      2. 22.8.2 Shutdown Sequence
    9. 22.9  I2S Configuration Guideline
    10. 22.10 I2S Registers
  24. 23Pulse Density Modulation (PDM)
    1. 23.1  Introduction
    2. 23.2  Block Diagram
    3. 23.3  Input Selection
      1. 23.3.1 PDM Data Mode
      2. 23.3.2 Manchester Input Mode
    4. 23.4  CIC Filter
      1. 23.4.1 Filter Design
      2. 23.4.2 Digital Filter Output
      3. 23.4.3 Offset Binary Mode
      4. 23.4.4 Twos-Complement Mode
    5. 23.5  FIFO Organization in Different Modes
      1. 23.5.1 Single Mono Microphone Configuration
        1. 23.5.1.1 24-bit Sample Size
          1. 23.5.1.1.1 32-bit Data Read
        2. 23.5.1.2 16-bit Sample Size
          1. 23.5.1.2.1 32-bit Data Read
          2. 23.5.1.2.2 16-bit Data Read
        3. 23.5.1.3 8-bit Sample Size
          1. 23.5.1.3.1 32-bit Data Read
          2. 23.5.1.3.2 16-bit Data Read
          3. 23.5.1.3.3 8-bit Data Read
      2. 23.5.2 Stereo or Dual Mono Microphone Configuration
        1. 23.5.2.1 24-bit Sample Size
          1. 23.5.2.1.1 32-bit Data Read
        2. 23.5.2.2 16-bit Sample Size
          1. 23.5.2.2.1 32-bit Data Read
          2. 23.5.2.2.2 16-bit Data Read
        3. 23.5.2.3 8-bit Sample Size
          1. 23.5.2.3.1 32-bit Data Read
          2. 23.5.2.3.2 16-bit Data Read
          3. 23.5.2.3.3 8-bit Data Read
      3. 23.5.3 FIFO Threshold Setting
      4. 23.5.4 Reset FIFO
    6. 23.6  Automatic Gain Control (AGC)
      1. 23.6.1 Operation in 2's Complement Format
      2. 23.6.2 Operation in Offset Binary Format
    7. 23.7  Interrupts
    8. 23.8  Clock Select and Control
    9. 23.9  DMA Operation
    10. 23.10 Samplestamp Generator
      1. 23.10.1 Samplestamp Counters
      2. 23.10.2 Start-Up Triggers
      3. 23.10.3 Samplestamp Capture
      4. 23.10.4 Achieving Constant Audio Latency
    11. 23.11 Debug‑Mode Flag Behavior
    12. 23.12 Software Guidelines
    13. 23.13 PDM Registers
  25. 24Analog to Digital Converter (ADC)
    1. 24.1 Overview
    2. 24.2 Block Diagram
    3. 24.3 Functional Description
      1. 24.3.1  ADC Core
      2. 24.3.2  Voltage Reference Options
      3. 24.3.3  Internal Channels
      4. 24.3.4  Resolution Modes
      5. 24.3.5  ADC Clocking
      6. 24.3.6  Power Down Behavior
      7. 24.3.7  Sampling Trigger Sources and Sampling Modes
        1. 24.3.7.1 AUTO Sampling Mode
        2. 24.3.7.2 MANUAL Sampling Mode
      8. 24.3.8  Sampling Period
      9. 24.3.9  Conversion Modes
      10. 24.3.10 ADC Data Format
      11. 24.3.11 Status Register
      12. 24.3.12 ADC Events
        1. 24.3.12.1 Generic Event Publishers (INT_EVENT0 & INT_EVENT1)
        2. 24.3.12.2 DMA Trigger Event Publisher (INT_EVENT2)
        3. 24.3.12.3 Generic Event Subscriber
      13. 24.3.13 Advanced Features
        1. 24.3.13.1 Window Comparator
        2. 24.3.13.2 DMA & FIFO Operation
          1. 24.3.13.2.1 DMA/CPU Operation in Non-FIFO Mode (FIFOEN=0)
          2. 24.3.13.2.2 DMA/CPU Operation in FIFO Mode (FIFOEN=1)
          3. 24.3.13.2.3 DMA/CPU Operation Summary Matrix
        3. 24.3.13.3 Ad-hoc Single Conversion
    4. 24.4 ADC Registers
  26. 25Controller Area Network (CAN)
    1. 25.1 Introduction
    2. 25.2 Functions
    3. 25.3 DCAN Subsystem
    4. 25.4 DCAN Functional Description
      1. 25.4.1 Operating Modes
        1. 25.4.1.1 Software Initialization
        2. 25.4.1.2 Normal Operation
        3. 25.4.1.3 Restricted Operation Mode
        4. 25.4.1.4 Bus Monitoring Mode
        5. 25.4.1.5 Disabled Automatic Retransmission
          1. 25.4.1.5.1 Frame Transmission in DAR Mode
        6. 25.4.1.6 Power Down (Sleep Mode)
          1. 25.4.1.6.1 DCAN clock stop and wake operations
          2. 25.4.1.6.2 DCAN debug suspend operation
        7. 25.4.1.7 Test Modes
          1. 25.4.1.7.1 External Loop Back Mode
          2. 25.4.1.7.2 Internal Loop Back Mode
      2. 25.4.2 Timestamp Generation
        1. 25.4.2.1 Block Diagram
      3. 25.4.3 Timeout Counter
      4. 25.4.4 Rx Handling
        1. 25.4.4.1 Acceptance Filtering
          1. 25.4.4.1.1 Range Filter
          2. 25.4.4.1.2 Filter for specific IDs
          3. 25.4.4.1.3 Classic Bit Mask Filter
          4. 25.4.4.1.4 Standard Message ID Filtering
          5. 25.4.4.1.5 Extended Message ID Filtering
        2. 25.4.4.2 Rx FIFOs
          1. 25.4.4.2.1 Rx FIFO Blocking Mode
          2. 25.4.4.2.2 Rx FIFO Overwrite Mode
        3. 25.4.4.3 Dedicated Rx Buffers
          1. 25.4.4.3.1 Rx Buffer Handling
        4. 25.4.4.4 Debug on CAN Support
          1. 25.4.4.4.1 Filtering for Debug Messages
          2. 25.4.4.4.2 Debug Message Handling
      5. 25.4.5 Tx Handling
        1. 25.4.5.1 Transmit Pause
        2. 25.4.5.2 Dedicated Tx Buffers
        3. 25.4.5.3 Tx FIFO
        4. 25.4.5.4 Tx Queue
        5. 25.4.5.5 Mixed Dedicated Tx Buffers / Tx FIFO
        6. 25.4.5.6 Mixed Dedicated Tx Buffers / Tx Queue
        7. 25.4.5.7 Transmit Cancellation
        8. 25.4.5.8 Tx Event Handling
      6. 25.4.6 FIFO Acknowledge Handling
      7. 25.4.7 DCAN Message RAM
        1. 25.4.7.1 Message RAM Configuration
        2. 25.4.7.2 Rx Buffer and FIFO Element
        3. 25.4.7.3 Tx Buffer Element
        4. 25.4.7.4 Tx Event FIFO Element
        5. 25.4.7.5 Standard Message ID Filter Element
        6. 25.4.7.6 Extended Message ID Filter Element
      8. 25.4.8 Interrupt Requests
    5. 25.5 DCAN Wrapper
    6. 25.6 DCAN Clock Enable
    7. 25.7 DCAN Registers
  27. 26Revision History

5.1.2 Exception Types

The exception types are:

  • Reset: The exception model treats reset as a special form of exception. When reset is asserted, the operation of the processor stops, potentially at any point in an instruction. When either power-on or warm reset is de-asserted, execution restarts from the address provided by the reset entry in the ROM vector table. Execution restarts as privileged execution in Secure state in Thread mode. This exception is not banked between security states.
  • NMI: A Non-Maskable Interrupt (NMI) can be signaled by a peripheral or triggered by software. It is permanently enabled and has a fixed priority of -2. NMI can only be preempted by reset and, when it is Non-secure, by a Secure HardFault. If SCB.AIRCR[13] BFHFNMINS = 0, then the NMI is Secure. If SCB.AIRCR[13] BFHFNMINS = 1, then NMI is Non-secure.
  • HardFault: A HardFault is an exception that occurs because of an error during normal or exception processing. HardFaults have a fixed priority of at least -1, meaning they have higher priority than any exception with configurable priority. This exception is not banked between security states

    If SCB.AIRCR[13] BFHFNMINS = 0, HardFault handles all faults that are unable to preempt the current execution. The HardFault handler is always Secure.

    If SCB.AIRCR[13] BFHFNMINS = 1, HardFault handles faults that target Non-secure state that are unable to preempt the current execution.

    HardFaults that specifically target the Secure state when SCB.AIRCR[13] BFHFNMINS is set to 1 have a priority of -3 to ensure they can preempt any execution. A Secure HardFault at priority -3 is only enabled when SCB.AIRCR[13] BFHFNMINS is set to 1. Secure HardFault handles Secure faults that are unable to preempt current execution.

  • MemManage: A MemManage fault is an exception that occurs because of a memory protection violation, compared to the MPU or the fixed memory protection constraints, for both instruction and data memory transactions. This fault is always used to abort instruction accesses to Execute Never (XN) memory regions. This exception is banked between security states.
  • BusFault: A BusFault is an exception that occurs because of a memory-related violation for an instruction or data memory transaction. This might be from an error that is detected on a bus in the memory system. This exception is not banked between security states.

    If SCB.AIRCR[13] BFHFNMINS = 0, BusFaults target the Secure state.

    If SCB.AIRCR[13] BFHFNMINS = 1, BusFaults target the Non-secure state.

  • UsageFault: A UsageFault is an exception that occurs because of a fault related to instruction execution.

    This includes:

    • An undefined instruction
    • An illegal unaligned access
    • Invalid state on instruction execution
    • An error on exception return The following can cause a usage fault:
    • An unaligned address on word and halfword memory access
    • Division by zero

    This exception is banked between security states.

  • SecureFault: This exception is triggered by the various security checks that are performed. It is triggered, for example, when jumping from Non-secure code to an address in Secure code that is not marked as a valid entry point. Most systems choose to treat a Secure fault as a terminal condition that either halts or restarts the system. Any other handling of the SecureFault must be checked carefully to make sure that it does not inadvertently introduce a security vulnerability. SecureFaults always target the Secure state.
  • SVCall: A Supervisor Call (SVC) is an exception that is triggered by the SVC instruction. In an OS environment, applications can use SVC instructions to access OS kernel functions and device drivers. This exception is banked between security states.
  • DebugMonitor: A DebugMonitor exception. If halting debug is disabled and the debug monitor is enabled, a debug event causes a debug monitor exception when the group priority of the debug monitor exception is greater than the current execution priority.
  • PendSV: PendSV is an asynchronous request for system-level service. In an OS environment, use PendSV for context switching when no other exception is active. This exception is banked between Security states.
  • SysTick: A SysTick exception is an exception the system timer generates when it reaches zero. Software can also generate a SysTick exception. In an OS environment, the processor can use this exception as a system tick. This exception is banked between Security states.
  • Interrupt (IRQ): An interrupt, or IRQ, is an exception signaled by a peripheral, or generated by a software request. All interrupts are asynchronous to instruction execution. In the system, peripherals use interrupts to communicate with the processor. This exception is not banked between security states. Secure code can assign each interrupt to Secure or Non-secure state. By default, all interrupts are assigned to Secure state.

For an asynchronous exception, other than reset, the processor can execute extra instructions between the moment the exception is triggered and the moment the processor enters the exception handler. Privileged software can disable the exceptions that have configurable priority, as shown in the table above. An exception that targets Secure state cannot be disabled by Non-secure code.

Table 5-1 Exception Types
Exception Number IRQ Number Exception Type Priority Vector Address Activation
1 - Reset -4, the highest 0x00000004 Asynchronous
2 -14 NMI -2 0x00000008 Asynchronous
3 -13 Secure HardFault when SCB:AIRCR.BF HFNMINS is 1 -3 0x0000000C Synchronous
Secure HardFault when SCB:AIRCR.BF HFNMINS is 0 -1
HardFault -1
4 -12 MemManage Configurable 0x00000010 Synchronous
5 -11 BusFault Configurable 0x00000014 Synchronous
6 -10 UsageFault Configurable 0x00000018 Synchronous
7 -9 SecureFault Configurable 0x0000001C Synchronous
8-10 - Reserved - - -
11 -5 SVCall Configurable 0x0000002C Synchronous
12 -4 DebugMonitor Configurable 0x00000030 Synchronous
13 - Reserved - - -
14 -2 PendSV Configurable 0x00000038 Asynchronous
15 -1 SysTick Configurable 0x0000003C Asynchronous
16 and above 0 and above Interrupt (IRQ) Configurable 0x00000040 and above (increasing in steps of 4) Asynchronous
Note: To simplify the software layer, the CMSIS only uses IRQ numbers. It uses negative values for exceptions other than interrupts. The IPSR returns the Exception number.