System reset after Soft device assert

RE: System reset after Soft device assert

davidz — Wed, 07 Oct 2020 14:32:46 GMT

Thank you very much. It is clear now :)

RE: System reset after Soft device assert

run_ar — Wed, 07 Oct 2020 11:12:54 GMT

This function will prepare the error messages and Branch to the function app_error_fault_handler (The bl instruction at line 19)

Error handler documentation for reference: Error module

RE: System reset after Soft device assert

davidz — Tue, 06 Oct 2020 16:13:30 GMT

Thank you very much. I am using nrf52840 dk and project in release mode. I would like to double-confirm this, since I found that the code that forward the error to app_error_fault_handler is greyed out in app_error_handler_gcc.c. Instead, the following assembly code is used:

void app_error_handler(ret_code_t error_code, uint32_t line_num, const uint8_t * p_file_name)
{
    __ASM volatile(

    "push {lr}                      \n"

    /* reserve space on stack for error_info_t struct - preserve 8byte stack aligment */
    "sub sp, sp, %0                 \n"

    /* prepare error_info_t struct */
    "str r0, [sp, %1]               \n"
    "str r1, [sp, %3]               \n"
    "str r2, [sp, %2]               \n"

    /* prepare arguments and call function: app_error_fault_handler */
    "ldr r0, =%4                    \n"
    "mov r1, lr                     \n"
    "mov r2, sp                     \n"
    "bl  %5                         \n"

    /* release stack */
    "add sp, sp, %0                 \n"

    "pop {pc}                       \n"
    ".ltorg                         \n"

    : /* Outputs */
    : /* Inputs */
    "I" (APP_ERROR_ERROR_INFO_SIZE_ALIGNED_8BYTE),
    "I" (APP_ERROR_ERROR_INFO_OFFSET_ERR_CODE),
    "I" (APP_ERROR_ERROR_INFO_OFFSET_P_FILE_NAME),
    "I" (APP_ERROR_ERROR_INFO_OFFSET_LINE_NUM),
    "X" (NRF_FAULT_ID_SDK_ERROR),
    "X" (app_error_fault_handler)
    : /* Clobbers */
    "r0", "r1", "r2"
    );
}

RE: System reset after Soft device assert

run_ar — Tue, 06 Oct 2020 08:15:45 GMT

app_error_handler will forward the error to app_error_fault_handler, unless the app_error_fault_handler is redefined. Depending on the preprocessor flags this will either halt (in debug mode) or reset:

#ifndef DEBUG
    NRF_LOG_WARNING("System reset");
    NVIC_SystemReset();
#else
    app_error_save_and_stop(id, pc, info);
#endif // DEBUG