SWRU622 August   2024 AWRL1432 , AWRL6432 , IWRL1432 , IWRL6432 , IWRL6432AOP

 

  1.   1
  2.   Trademarks
  3. 1Introduction
  4. 2Basic Bootloader Flow
    1. 2.1 Programming Serial Data Flash Over UART (Bootloader Service)
    2. 2.2 Binary File Format
    3. 2.3 Flash Programming Sequence
    4. 2.4 Supported UART Commands/Response and Format
    5. 2.5 Flashing Sequence
    6. 2.6 ROM-Assisted Image Download Sequence
    7. 2.7 Booting Application Image
      1. 2.7.1 Booting From Serial Flash
      2. 2.7.2 Bootmode – SPI
      3. 2.7.3 Bootmode - UART
  5. 3Secondary Bootloader
    1. 3.1 SBL Execution Flow
      1. 3.1.1 Flash Memory Partitioning for SBL Execution
      2. 3.1.2 SBL Feature Modifications
      3. 3.1.3 SBL Development Considerations
  6. 4Warm Reset
    1. 4.1 Integrity Verification
    2. 4.2 LSTC/PBIST
    3. 4.3 Watchdog Timer
    4. 4.4 Reset-Triggered Flash Reload of Application
      1. 4.4.1 Hardware Solutions
        1. 4.4.1.1 PMIC I2C Messaging
        2. 4.4.1.2 External Watchdog Timer
        3. 4.4.1.3 External Voltage Monitoring or Voltage Supervisors
      2. 4.4.2 Software Solutions
        1. 4.4.2.1 Setting Boot Vector to 0x0
  7. 5Relevant Registers
    1. 5.1 Reset Registers
    2. 5.2 PC Registers
      1. 5.2.1 Addresses

4.3 Watchdog Timer

A watchdog timer module is available on the xWRLx432 device. A watchdog timer can act as a last method of defense against runaway code or infinitely looping code. This can prevent the device from entering an unknown state and can result in unknown power draw or loss of communication within a larger system.

xWRLx432 WDT Coverage Figure 4-1 xWRLx432 WDT Coverage.

The WDT does not provide coverage when the device is in low power/deep sleep mode

The internal watchdog is not meant to cover all failure modes on the device, which includes but is not limited to random bit flips or transient faults. An appropriate functional safety assessment must be taken by the system integrator to determine if the internal watchdog is sufficient for the use-case.