SLAU923B June   2025  â€“ April 2026 MSPM0H3215 , MSPM0H3216 , MSPM0H3216-Q1

 

  1.   1
  2.   Read This First
    1.     About This Manual
    2.     Notational Conventions
    3.     Glossary
    4.     Related Documentation
    5.     Support Resources
    6.     Trademarks
  3. 1 Architecture
    1. 1.1 Architecture Overview
    2. 1.2 Bus Organization
    3. 1.3 Platform Memory Map
      1. 1.3.1 Code Region
      2. 1.3.2 SRAM Region
      3. 1.3.3 Peripheral Region
      4. 1.3.4 Subsystem Region
      5. 1.3.5 System PPB Region
    4. 1.4 Boot Configuration
      1. 1.4.1 Configuration Memory (NONMAIN)
        1. 1.4.1.1 CRC-Backed Configuration Data
        2. 1.4.1.2 16-bit Pattern Match for Critical Fields
      2. 1.4.2 Boot Configuration Routine (BCR)
        1. 1.4.2.1 Serial Wire Debug Related Policies
          1. 1.4.2.1.1 SWD Security Level 0
          2. 1.4.2.1.2 SWD Security Level 1
          3. 1.4.2.1.3 SWD Security Level 2
        2. 1.4.2.2 SWD Factory Reset Commands
        3. 1.4.2.3 Flash Memory Protection and Integrity Related Policies
          1. 1.4.2.3.1 Locking the Application (MAIN) Flash Memory
          2. 1.4.2.3.2 Locking the Configuration (NONMAIN) Flash Memory
          3. 1.4.2.3.3 Static Write Protection NONMAIN Fields
        4. 1.4.2.4 Fast Boot
      3. 1.4.3 NONMAIN Layout Types
      4. 1.4.4 NONMAIN_TYPED Registers
    5. 1.5 Factory Constants
      1. 1.5.1 FACTORYREGION Layout Types
      2. 1.5.2 FACTORYREGION_TYPEA Registers
  4. 2 PMCU
    1. 2.1 PMCU Overview
      1. 2.1.1 Power Domains
      2. 2.1.2 Operating Modes
        1. 2.1.2.1 RUN Mode
        2. 2.1.2.2 SLEEP Mode
        3. 2.1.2.3 STOP Mode
        4. 2.1.2.4 STANDBY Mode
        5. 2.1.2.5 SHUTDOWN Mode
        6. 2.1.2.6 Supported Functionality by Operating Mode
        7. 2.1.2.7 Suspended Low-Power Mode Operation
    2. 2.2 Power Management (PMU)
      1. 2.2.1 Power Supply
      2. 2.2.2 Core Regulator
      3. 2.2.3 Supply Supervisors
        1. 2.2.3.1 Power-on Reset (POR)
        2. 2.2.3.2 Brownout Reset (BOR)
        3. 2.2.3.3 POR and BOR Behavior During Supply Changes
      4. 2.2.4 Bandgap Reference
      5. 2.2.5 Peripheral Enable
        1. 2.2.5.1 Automatic Peripheral Disable in Low Power Modes
    3. 2.3 Clock Module (CKM)
      1. 2.3.1 Oscillators
        1. 2.3.1.1 Internal Low-Frequency Oscillator (LFOSC)
        2. 2.3.1.2 Internal System Oscillator (SYSOSC)
          1. 2.3.1.2.1 SYSOSC Gear Shift
          2. 2.3.1.2.2 SYSOSC Frequency
          3. 2.3.1.2.3 SYSOSC Frequency Correction Loop
            1. 2.3.1.2.3.1 SYSOSC FCL in External Resistor Mode (ROSC)
            2. 2.3.1.2.3.2 SYSOSC FCL in Internal Resistor Mode
          4. 2.3.1.2.4 SYSOSC User Trim Procedure
          5. 2.3.1.2.5 Disabling SYSOSC
        3. 2.3.1.3 Low Frequency Crystal Oscillator (LFXT)
        4. 2.3.1.4 LFCLK_IN (Digital Clock)
        5. 2.3.1.5 High Frequency Crystal Oscillator (HFXT)
        6. 2.3.1.6 HFCLK_IN (Digital clock)
      2. 2.3.2 Clocks
        1. 2.3.2.1  MCLK (Main Clock) Tree
        2. 2.3.2.2  CPUCLK (Processor Clock)
        3. 2.3.2.3  ULPCLK (Low-Power Clock)
        4. 2.3.2.4  MFCLK (Middle Frequency Clock)
        5. 2.3.2.5  MFPCLK (Middle Frequency Precision Clock)
        6. 2.3.2.6  LFCLK (Low-Frequency Clock)
        7. 2.3.2.7  HFCLK (High-Frequency External Clock)
        8. 2.3.2.8  HSCLK (High Speed Clock)
        9. 2.3.2.9  ADCCLK (ADC Sample Period Clock)
        10. 2.3.2.10 CANCLK (CAN-FD Functional Clock)
        11. 2.3.2.11 RTCCLK (RTC Clock)
        12. 2.3.2.12 External Clock Output (CLK_OUT)
        13. 2.3.2.13 Direct Clock Connections for Infrastructure
      3. 2.3.3 Clock Tree
        1. 2.3.3.1 Peripheral Clock Source Selection
      4. 2.3.4 Clock Monitors
        1. 2.3.4.1 LFCLK Monitor
        2. 2.3.4.2 MCLK Monitor
        3. 2.3.4.3 Startup Monitors
          1. 2.3.4.3.1 LFOSC Startup Monitor
          2. 2.3.4.3.2 LFXT Startup Monitor
          3. 2.3.4.3.3 HFCLK Startup Monitor
          4. 2.3.4.3.4 HSCLK Status
      5. 2.3.5 Frequency Clock Counter (FCC)
        1. 2.3.5.1 Using the FCC
        2. 2.3.5.2 FCC Frequency Computation and Accuracy
    4. 2.4 System Controller (SYSCTL)
      1. 2.4.1  Resets and Device Initialization
        1. 2.4.1.1 Reset Levels
          1. 2.4.1.1.1 Power-on Reset (POR) Reset Level
          2. 2.4.1.1.2 Brownout Reset (BOR) Reset Level
          3. 2.4.1.1.3 Boot Reset (BOOTRST) Reset Level
          4. 2.4.1.1.4 System Reset (SYSRST) Reset Level
          5. 2.4.1.1.5 CPU-only Reset (CPURST) Reset Level
        2. 2.4.1.2 Initial Conditions After Power-Up
        3. 2.4.1.3 NRST Pin
        4. 2.4.1.4 SWD Pins
        5. 2.4.1.5 Generating Resets in Software
        6. 2.4.1.6 Reset Cause
        7. 2.4.1.7 Peripheral Reset Control
        8. 2.4.1.8 Boot Fail Handling
      2. 2.4.2  Operating Mode Selection
      3. 2.4.3  Asynchronous Fast Clock Requests
      4. 2.4.4  SRAM Write Protection
      5. 2.4.5  Flash Wait States
      6. 2.4.6  Shutdown Mode Handling (if present)
      7. 2.4.7  Configuration Lockout
      8. 2.4.8  System Status
      9. 2.4.9  Error Handling
      10. 2.4.10 SYSCTL Events
        1. 2.4.10.1 CPU Interrupt Event (CPU_INT)
        2. 2.4.10.2 Nonmaskable Interrupt Event (NMI)
    5. 2.5 SYSCTL_H3215_H3216 Registers
    6. 2.6 Quick Start Reference
      1. 2.6.1 Default Device Configuration
      2. 2.6.2 Leveraging MFCLK
      3. 2.6.3 Optimizing Power Consumption in STOP Mode
      4. 2.6.4 Optimizing Power Consumption in STANDBY Mode
      5. 2.6.5 Increasing MCLK Precision
      6. 2.6.6 High Speed Clock (SYSPLL, HFCLK) Handling in Low-Power Modes
      7. 2.6.7 Optimizing for Lowest Wakeup Latency
      8. 2.6.8 Optimizing for Lowest Peak Current in RUN/SLEEP Mode
  5. 3 CPU
    1. 3.1 Overview
    2. 3.2 Arm Cortex-M0+ CPU
      1. 3.2.1 CPU Register File
      2. 3.2.2 Stack Behavior
      3. 3.2.3 Execution Modes and Privilege Levels
      4. 3.2.4 Address Space and Supported Data Sizes
    3. 3.3 Interrupts and Exceptions
      1. 3.3.1 Peripheral Interrupts (IRQs)
        1. 3.3.1.1 Nested Vectored Interrupt Controller (NVIC)
        2. 3.3.1.2 Interrupt Groups
        3. 3.3.1.3 Wake Up Controller (WUC)
      2. 3.3.2 Interrupt and Exception Table
      3. 3.3.3 Processor Lockup Scenario
    4. 3.4 CPU Peripherals
      1. 3.4.1 System Control Block (SCB)
    5. 3.5 Read-Only Memory (ROM)
    6. 3.6 CPUSS Registers
    7. 3.7 WUC Registers
  6. 4 SECURITY
    1. 4.1 Overview
      1. 4.1.1 Secure Boot
      2. 4.1.2 Customer Secure Code (CSC)
    2. 4.2 Boot and Startup Sequence
      1. 4.2.1 CSC Programming Overview
    3. 4.3 Secure Key Storage
    4. 4.4 Flash Memory Protection
      1. 4.4.1 Bank Swapping
      2. 4.4.2 Write Protection
      3. 4.4.3 Read-Execute Protection
      4. 4.4.4 IP Protection
      5. 4.4.5 Data Bank Protection
      6. 4.4.6 Hardware Monotonic Counter
    5. 4.5 SRAM Protection
    6. 4.6 SECURITY Registers
  7. 5 Direct Memory Access (DMA)
    1. 5.1 DMA Overview
    2. 5.2 DMA Operation
      1. 5.2.1  Addressing Modes
      2. 5.2.2  Channel Types
      3. 5.2.3  Transfer Modes
        1. 5.2.3.1 Single Transfer
        2. 5.2.3.2 Block Transfer
        3. 5.2.3.3 Repeated Single Transfer
        4. 5.2.3.4 Repeated Block Transfer
        5. 5.2.3.5 Stride Mode
      4. 5.2.4  Extended Modes
        1. 5.2.4.1 Fill Mode
        2. 5.2.4.2 Table Mode
      5. 5.2.5  Initiating DMA Transfers
      6. 5.2.6  Stopping DMA Transfers
      7. 5.2.7  Channel Priorities
      8. 5.2.8  Burst Block Mode
      9. 5.2.9  Using DMA with System Interrupts
      10. 5.2.10 DMA Controller Interrupts
      11. 5.2.11 DMA Trigger Event Status
      12. 5.2.12 DMA Operating Mode Support
        1. 5.2.12.1 Transfer in RUN Mode
        2. 5.2.12.2 Transfer in SLEEP Mode
        3. 5.2.12.3 Transfer in STOP Mode
        4. 5.2.12.4 Transfers in STANDBY Mode
      13. 5.2.13 DMA Address and Data Errors
      14. 5.2.14 Interrupt and Event Support
    3. 5.3 DMA Registers
  8. 6 NVM (Flash)
    1. 6.1 NVM Overview
      1. 6.1.1 Key Features
      2. 6.1.2 System Components
      3. 6.1.3 Terminology
    2. 6.2 Flash Memory Bank Organization
      1. 6.2.1 Banks
      2. 6.2.2 Flash Memory Regions
      3. 6.2.3 Addressing
        1. 6.2.3.1 Flash Memory Map
      4. 6.2.4 Memory Organization Examples
    3. 6.3 Flash Controller
      1. 6.3.1 Overview of Flash Controller Commands
      2. 6.3.2 NOOP Command
      3. 6.3.3 PROGRAM Command
        1. 6.3.3.1 Program Bit Masking Behavior
        2. 6.3.3.2 Programming Less Than One Flash Word
        3. 6.3.3.3 Target Data Alignment (Devices with Single Flash Word Programming Only)
        4. 6.3.3.4 Target Data Alignment (Devices With Multiword Programming)
        5. 6.3.3.5 Executing a PROGRAM Operation
      4. 6.3.4 ERASE Command
        1. 6.3.4.1 Erase Sector Masking Behavior
        2. 6.3.4.2 Executing an ERASE Operation
      5. 6.3.5 READVERIFY Command
        1. 6.3.5.1 Executing a READVERIFY Operation
      6. 6.3.6 BLANKVERIFY Command
        1. 6.3.6.1 Executing a BLANKVERIFY Operation
      7. 6.3.7 Command Diagnostics
        1. 6.3.7.1 Command Status
        2. 6.3.7.2 Address Translation
        3. 6.3.7.3 Pulse Counts
      8. 6.3.8 Overriding the System Address With a Bank ID, Region ID, and Bank Address
      9. 6.3.9 FLASHCTL Events
        1. 6.3.9.1 CPU Interrupt Event Publisher
    4. 6.4 Write Protection
      1. 6.4.1 Write Protection Resolution
      2. 6.4.2 Static Write Protection
      3. 6.4.3 Dynamic Write Protection
        1. 6.4.3.1 Configuring Protection for the MAIN Region
        2. 6.4.3.2 Configuring Protection for the NONMAIN Region
    5. 6.5 Read Interface
      1. 6.5.1 Bank Address Swapping
    6. 6.6 FLASHCTL Registers
  9. 7 Events
    1. 7.1 Events Overview
      1. 7.1.1 Event Publisher
      2. 7.1.2 Event Subscriber
      3. 7.1.3 Event Fabric Routing
        1. 7.1.3.1 CPU Interrupt Event Route (CPU_INT)
        2. 7.1.3.2 DMA Trigger Event Route (DMA_TRIGx)
        3. 7.1.3.3 Generic Event Route (GEN_EVENTx)
      4. 7.1.4 Event Routing Map
      5. 7.1.5 Event Propagation Latency
    2. 7.2 Events Operation
      1. 7.2.1 CPU Interrupt
      2. 7.2.2 DMA Trigger
      3. 7.2.3 Peripheral to Peripheral Event
      4. 7.2.4 Extended Module Description Register
      5. 7.2.5 Using Event Registers
        1. 7.2.5.1 Event Registers
        2. 7.2.5.2 Configuring Events
        3. 7.2.5.3 Responding to CPU Interrupts in Application Software
        4. 7.2.5.4 Hardware Event Handling
  10. 8 IOMUX
    1. 8.1 IOMUX Overview
      1. 8.1.1 IO Types and Analog Sharing
    2. 8.2 IOMUX Operation
      1. 8.2.1 Peripheral Function (PF) Assignment
      2. 8.2.2 Logic High to Hi-Z Conversion
      3. 8.2.3 Logic Inversion
      4. 8.2.4 SHUTDOWN Mode Wakeup Logic
      5. 8.2.5 Pullup/Pulldown Resistors
      6. 8.2.6 Drive Strength Control
      7. 8.2.7 Hysteresis and Logic Level Control
    3. 8.3 IOMUX Registers
  11. 9 General-Purpose Input/Output (GPIO)
    1. 9.1 GPIO Overview
    2. 9.2 GPIO Operation
      1. 9.2.1 GPIO Ports
      2. 9.2.2 GPIO Read/Write Interface
      3. 9.2.3 GPIO Input Glitch Filtering and Synchronization
      4. 9.2.4 GPIO Fast Wake
      5. 9.2.5 GPIO DMA Interface
      6. 9.2.6 Event Publishers and Subscribers
    3. 9.3 GPIO Registers
  12. 10ADC
    1. 10.1 ADC Overview
    2. 10.2 ADC Operation
      1. 10.2.1  ADC Core
      2. 10.2.2  Voltage Reference Options
      3. 10.2.3  Generic Resolution Modes
      4. 10.2.4  Hardware Averaging
      5. 10.2.5  ADC Clocking
      6. 10.2.6  Common ADC Use Cases
      7. 10.2.7  Power Down Behavior
      8. 10.2.8  Sampling Trigger Sources and Sampling Modes
        1. 10.2.8.1 AUTO Sampling Mode
        2. 10.2.8.2 MANUAL Sampling Mode
      9. 10.2.9  Sampling Period
      10. 10.2.10 Conversion Modes
      11. 10.2.11 Data Format
      12. 10.2.12 Advanced Features
        1. 10.2.12.1 Window Comparator
        2. 10.2.12.2 DMA and FIFO Operation
        3. 10.2.12.3 Analog Peripheral Interconnection
      13. 10.2.13 Status Register
      14. 10.2.14 ADC Events
        1. 10.2.14.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 10.2.14.2 Generic Event Publisher (GEN_EVENT)
        3. 10.2.14.3 DMA Trigger Event Publisher (DMA_TRIG)
        4. 10.2.14.4 Generic Event Subscriber (FSUB_0)
    3. 10.3 ADC12 Registers
  13. 11VREF
    1. 11.1 VREF Overview
    2. 11.2 VREF Operation
      1. 11.2.1 Internal Reference Generation
      2. 11.2.2 External Reference Input
      3. 11.2.3 Analog Peripheral Interface
    3. 11.3 VREF Registers
  14. 12UART
    1. 12.1 UART Overview
      1. 12.1.1 Purpose of the Peripheral
      2. 12.1.2 Features
      3. 12.1.3 Functional Block Diagram
    2. 12.2 UART Operation
      1. 12.2.1 Clock Control
      2. 12.2.2 Signal Descriptions
      3. 12.2.3 General Architecture and Protocol
        1. 12.2.3.1  Transmit Receive Logic
        2. 12.2.3.2  Bit Sampling
        3. 12.2.3.3  Majority Voting Feature
        4. 12.2.3.4  Baud Rate Generation
        5. 12.2.3.5  Data Transmission
        6. 12.2.3.6  Error and Status
        7. 12.2.3.7  Local Interconnect Network (LIN) Support
          1. 12.2.3.7.1 LIN Responder Transmission Delay
        8. 12.2.3.8  Flow Control
        9. 12.2.3.9  Idle-Line Multiprocessor
        10. 12.2.3.10 9-Bit UART Mode
        11. 12.2.3.11 RS-485 Support
        12. 12.2.3.12 DALI Protocol
        13. 12.2.3.13 Manchester Encoding and Decoding
        14. 12.2.3.14 IrDA Encoding and Decoding
        15. 12.2.3.15 ISO7816 Smart Card Support
        16. 12.2.3.16 Address Detection
        17. 12.2.3.17 FIFO Operation
        18. 12.2.3.18 Loopback Operation
        19. 12.2.3.19 Glitch Suppression
      4. 12.2.4 Low Power Operation
      5. 12.2.5 Reset Considerations
      6. 12.2.6 Initialization
      7. 12.2.7 Interrupt and Events Support
        1. 12.2.7.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 12.2.7.2 DMA Trigger Publisher (DMA_TRIG_RX, DMA_TRIG_TX)
      8. 12.2.8 Emulation Modes
    3. 12.3 UART Registers
  15. 13SPI
    1. 13.1 SPI Overview
      1. 13.1.1 Purpose of the Peripheral
      2. 13.1.2 Features
      3. 13.1.3 Functional Block Diagram
      4. 13.1.4 External Connections and Signal Descriptions
    2. 13.2 SPI Operation
      1. 13.2.1 Clock Control
      2. 13.2.2 General Architecture
        1. 13.2.2.1 Chip Select and Command Handling
          1. 13.2.2.1.1 Chip Select Control
          2. 13.2.2.1.2 Command Data Control
        2. 13.2.2.2 Data Format
        3. 13.2.2.3 Delayed data sampling
        4. 13.2.2.4 Clock Generation
        5. 13.2.2.5 FIFO Operation
        6. 13.2.2.6 Loopback mode
        7. 13.2.2.7 DMA Operation
        8. 13.2.2.8 Repeat Transfer mode
        9. 13.2.2.9 Low Power Mode
      3. 13.2.3 Protocol Descriptions
        1. 13.2.3.1 Motorola SPI Frame Format
        2. 13.2.3.2 Texas Instruments Synchronous Serial Frame Format
      4. 13.2.4 Reset Considerations
      5. 13.2.5 Initialization
      6. 13.2.6 Interrupt and Events Support
        1. 13.2.6.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 13.2.6.2 DMA Trigger Publisher (DMA_TRIG_RX, DMA_TRIG_TX)
      7. 13.2.7 Emulation Modes
    3. 13.3 SPI Registers
  16. 14I2C
    1. 14.1 I2C Overview
      1. 14.1.1 Purpose of the Peripheral
      2. 14.1.2 Features
      3. 14.1.3 Functional Block Diagram
      4. 14.1.4 Environment and External Connections
    2. 14.2 I2C Operation
      1. 14.2.1 Clock Control
        1. 14.2.1.1 Clock Select and I2C Speed
        2. 14.2.1.2 Clock Startup
      2. 14.2.2 Signal Descriptions
      3. 14.2.3 General Architecture
        1. 14.2.3.1  I2C Bus Functional Overview
        2. 14.2.3.2  START and STOP Conditions
        3. 14.2.3.3  Data Format with 7-Bit Address
        4. 14.2.3.4  Data Format with 10-Bit Address
        5. 14.2.3.5  Acknowledge
        6. 14.2.3.6  Repeated Start
        7. 14.2.3.7  SCL Clock Low Timeout
        8. 14.2.3.8  Clock Stretching
        9. 14.2.3.9  Dual Address
        10. 14.2.3.10 Arbitration
        11. 14.2.3.11 Multiple Controller Mode
        12. 14.2.3.12 Glitch Suppression
        13. 14.2.3.13 FIFO operation
          1. 14.2.3.13.1 Flushing Stale Tx Data in Target Mode
        14. 14.2.3.14 Loopback mode
        15. 14.2.3.15 Burst Mode
        16. 14.2.3.16 DMA Operation
        17. 14.2.3.17 Low-Power Operation
      4. 14.2.4 Protocol Descriptions
        1. 14.2.4.1 I2C Controller Mode
          1. 14.2.4.1.1 Controller Configuration
          2. 14.2.4.1.2 Controller Mode Operation
          3. 14.2.4.1.3 Read On TX Empty
        2. 14.2.4.2 I2C Target Mode
          1. 14.2.4.2.1 Target Mode Operation
      5. 14.2.5 Reset Considerations
      6. 14.2.6 Initialization
      7. 14.2.7 Interrupt and Events Support
        1. 14.2.7.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 14.2.7.2 DMA Trigger Publisher (DMA_TRIG1, DMA_TRIG0)
      8. 14.2.8 Emulation Modes
    3. 14.3 I2C Registers
  17. 15CRC
    1. 15.1 CRC Overview
      1. 15.1.1 CRC16-CCITT
    2. 15.2 CRC Operation
      1. 15.2.1 CRC Generator Implementation
      2. 15.2.2 Configuration
        1. 15.2.2.1 Bit Order
        2. 15.2.2.2 Byte Swap
        3. 15.2.2.3 Byte Order
        4. 15.2.2.4 CRC C Library Compatibility
    3. 15.3 CRCP0 Registers
  18. 16Temperature Sensor
  19. 17Timers (TIMx)
    1. 17.1 TIMx Overview
      1. 17.1.1 TIMG Overview
        1. 17.1.1.1 TIMG Features
        2. 17.1.1.2 Functional Block Diagram
      2. 17.1.2 TIMA Overview
        1. 17.1.2.1 TIMA Features
        2. 17.1.2.2 Functional Block Diagram
      3. 17.1.3 TIMx Instance Configuration
    2. 17.2 TIMx Operation
      1. 17.2.1  Timer Counter
        1. 17.2.1.1 Clock Source Select and Prescaler
          1. 17.2.1.1.1 Internal Clock and Prescaler
          2. 17.2.1.1.2 External Signal Trigger
        2. 17.2.1.2 Repeat Counter (TIMA only)
      2. 17.2.2  Counting Mode Control
        1. 17.2.2.1 One-shot and Periodic Modes
        2. 17.2.2.2 Down Counting Mode
        3. 17.2.2.3 Up/Down Counting Mode
        4. 17.2.2.4 Up Counting Mode
        5. 17.2.2.5 Phase Load (TIMA only)
      3. 17.2.3  Capture/Compare Module
        1. 17.2.3.1 Capture Mode
          1. 17.2.3.1.1 Input Selection, Counter Conditions, and Inversion
            1. 17.2.3.1.1.1 CCP Input Edge Synchronization
            2. 17.2.3.1.1.2 CCP Input Pulse Conditions
            3. 17.2.3.1.1.3 Counter Control Operation
            4. 17.2.3.1.1.4 CCP Input Filtering
            5. 17.2.3.1.1.5 Input Selection
          2. 17.2.3.1.2 Use Cases
            1. 17.2.3.1.2.1 Edge Time Capture
            2. 17.2.3.1.2.2 Period Capture
            3. 17.2.3.1.2.3 Pulse Width Capture
            4. 17.2.3.1.2.4 Combined Pulse Width and Period Time
          3. 17.2.3.1.3 QEI Mode (TIMG with QEI support only)
            1. 17.2.3.1.3.1 QEI With 2-Signal
            2. 17.2.3.1.3.2 QEI With Index Input
            3. 17.2.3.1.3.3 QEI Error Detection
          4. 17.2.3.1.4 Hall Input Mode (TIMG with QEI support only)
        2. 17.2.3.2 Compare Mode
          1. 17.2.3.2.1 Edge Count
      4. 17.2.4  Shadow Load and Shadow Compare
        1. 17.2.4.1 Shadow Load (TIMG4-7, TIMA only)
        2. 17.2.4.2 Shadow Compare (TIMG4-7, TIMG12-13, TIMA only)
      5. 17.2.5  Output Generator
        1. 17.2.5.1 Configuration
        2. 17.2.5.2 Use Cases
          1. 17.2.5.2.1 Edge-Aligned PWM
          2. 17.2.5.2.2 Center-Aligned PWM
          3. 17.2.5.2.3 Asymmetric PWM (TIMA only)
          4. 17.2.5.2.4 Complementary PWM With Deadband Insertion (TIMA only)
        3. 17.2.5.3 Forced Output
      6. 17.2.6  Fault Handler (TIMA only)
        1. 17.2.6.1 Fault Input Conditioning
        2. 17.2.6.2 Fault Input Sources
        3. 17.2.6.3 Counter Behavior With Fault Conditions
        4. 17.2.6.4 Output Behavior With Fault Conditions
      7. 17.2.7  Synchronization With Cross Trigger
        1. 17.2.7.1 Main Timer Cross Trigger Configuration
        2. 17.2.7.2 Secondary Timer Cross Trigger Configuration
      8. 17.2.8  Low Power Operation
      9. 17.2.9  Interrupt and Event Support
        1. 17.2.9.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 17.2.9.2 Generic Event Publisher and Subscriber (GEN_EVENT0 and GEN_EVENT1)
        3. 17.2.9.3 Generic Subscriber Event Example (COMP to TIMx)
      10. 17.2.10 Debug Handler (TIMA Only)
    3. 17.3 TIMx Registers
  20. 18Low Frequency Subsystem (LFSS_B)
    1. 18.1 Overview
    2. 18.2 Clock System
    3. 18.3 LFSS Reset
    4. 18.4 Real Time Counter (RTC_x)
    5. 18.5 Independent Watchdog Timer (IWDT)
    6. 18.6 Lock Function of RTC and IWDT
    7. 18.7 LFSS Registers
  21. 19RTC
    1. 19.1 Overview
      1. 19.1.1 RTC Instances
    2. 19.2 Basic Operation
    3. 19.3 Configuration
      1. 19.3.1  Clocking
      2. 19.3.2  Reading and Writing to RTC Peripheral Registers
      3. 19.3.3  Binary vs. BCD
      4. 19.3.4  Leap Year Handling
      5. 19.3.5  Calendar Alarm Configuration
      6. 19.3.6  Interval Alarm Configuration
      7. 19.3.7  Periodic Alarm Configuration
      8. 19.3.8  Calibration
        1. 19.3.8.1 Crystal Offset Error
          1. 19.3.8.1.1 Offset Error Correction Mechanism
        2. 19.3.8.2 Crystal Temperature Error
          1. 19.3.8.2.1 Temperature Drift Correction Mechanism
      9. 19.3.9  RTC Prescaler Extension
      10. 19.3.10 RTC Timestamp Capture
      11. 19.3.11 RTC Events
        1. 19.3.11.1 CPU Interrupt Event Publisher (CPU_INT)
        2. 19.3.11.2 Generic Event Publisher (GEN_EVENT)
    4. 19.4 RTC Registers
  22. 20IWDT
    1. 20.1 542
    2. 20.2 IWDT Clock Configuration
    3. 20.3 IWDT Period Selection
    4. 20.4 Debug Behavior of the IWDT
    5. 20.5 IWDT Registers
  23. 21Window Watchdog Timer (WWDT)
    1. 21.1 WWDT Overview
      1. 21.1.1 Watchdog Mode
      2. 21.1.2 Interval Timer Mode
    2. 21.2 WWDT Operation
      1. 21.2.1 Mode Selection
      2. 21.2.2 Clock Configuration
      3. 21.2.3 Low-Power Mode Behavior
      4. 21.2.4 Debug Behavior
      5. 21.2.5 WWDT Events
        1. 21.2.5.1 CPU Interrupt Event Publisher (CPU_INT)
    3. 21.3 WWDT Registers
  24. 22Debug
    1. 22.1 DEBUGSS Overview
      1. 22.1.1 Debug Interconnect
      2. 22.1.2 Physical Interface
      3. 22.1.3 Debug Access Ports
    2. 22.2 DEBUGSS Operation
      1. 22.2.1 Debug Features
        1. 22.2.1.1 Processor Debug
          1. 22.2.1.1.1 Breakpoint Unit (BPU)
          2. 22.2.1.1.2 Data Watchpoint and Trace Unit (DWT)
        2. 22.2.1.2 Peripheral Debug
        3. 22.2.1.3 EnergyTrace Technology
      2. 22.2.2 Behavior in Low Power Modes
      3. 22.2.3 Restricting Debug Access
      4. 22.2.4 Mailbox (DSSM)
        1. 22.2.4.1 DSSM Events
          1. 22.2.4.1.1 CPU Interrupt Event (CPU_INT)
        2. 22.2.4.2 Reference
    3. 22.3 DEBUGSS Registers
  25. 23Revision History

2.3.2.6 LFCLK (Low-Frequency Clock)

LFCLK provides a continuous 32kHz clock to a variety of peripherals on the device. After a BOOTRST, LFCLK is initially sourced by the internal 32kHz oscillator (LFOSC). After boot, LFCLK can be switched by software to either the low-frequency crystal oscillator (LFXT) or the low-frequency digital clock input (LFCLK_IN). See the respective oscillator section for instructions on switching the LFCLK source. When the LFCLK source is changed, the change is locked and LFOSC is disabled to save power. It is not possible to again select LFOSC as the LFCLK source without executing a BOOTRST.

Note: If LFCLK is to be selected as the MCLK source, and LFXT or LFCLK_IN are to be used as the LFCLK source, configure the LFXT or LFCLK_IN as the LFCLK source before selecting LFCLK as the source for MCLK.

LFCLK is active in RUN, SLEEP, STOP, and STANDBY power modes. It is possible to disable both ULPCLK and LFCLK together to most peripherals in STANDBY mode to achieve the lowest possible STANDBY mode power consumption (STANDBY1). To do so, set the STOPCLKSTBY bit in the MCLKCFG register in SYSCTL before entering STANDBY. In this state, the RTC and a few times are the only clocked peripherals.

LFCLK is a synchronized clock. All LFCLK edges are synchronized to the main system clocks (MCLK and ULPCLK), meaning that the registers of peripherals clocked by LFCLK can be read or written to at any time without any special handling. The RTC is the only exception to this rule, as the RTC receives RTCCLK which is the asynchronous LFCLK.
Note:

When MCLK/ULPCLK are not sourced by LFCLK (for example, when they are sourced by SYSOSC) there is a 5 ULPCLK cycle synchronization delay between the low frequency clock source's clock edge and the corresponding LFCLK edge as seen by peripherals running from LFCLK. When the MCLK/ULPCLK frequency is constant, this delay is constant and it does not add jitter to LFCLK. If the MCLK/ULPCLK frequency changes, the synchronization delay changes proportionally and this results in a small single-cycle LFCLK jitter at the MCLK/ULPCLK frequency transition point. This jitter changes the duty cycle of one LFCLK period, but there is no accumulation of error (there is never a change in the number of LFCLK periods, ensuring an accurate LFCLK time base for peripherals).

Peripherals can select LFCLK as their functional clock source through their respective CLKSEL mux. Not all peripherals support running from LFCLK. It is possible to run the main clock (MCLK) from LFCK, in which case the entire device runs at the LFCLK rate (32kHz).