ESP32 Forum

Posted: **Wed Oct 29, 2025 8:48 am**

Hi everyone,

I’m encountering a Watchdog Reset on my ESP32-S3 after 10-15 hours of working.
Here is the relevant part of the boot log:

Code: Select all

rst:0x8 (TG1WDT_SYS_RST),boot:0x9 (SPI_FAST_FLASH_BOOT)
Saved PC:0x42004bcf
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fce3810,len:0x164c
load:0x403c9700,len:0xbcc
load:0x403cc700,len:0x2e20
entry 0x403c9904
I (25) boot: ESP-IDF v5.0.1-dirty 2nd stage bootloader
I (25) boot: compile time 18:13:36
I (25) boot: chip revision: v0.2
I (27) boot.esp32s3: Boot SPI Speed : 80MHz
I (32) boot.esp32s3: SPI Mode       : DIO
I (37) boot.esp32s3: SPI Flash Size : 8MB
W (42) boot.esp32s3: PRO CPU has been reset by WDT.
W (47) boot.esp32s3: APP CPU has been reset by WDT.
I (53) boot: Enabling RNG early entropy source...
I (58) boot: Partition Table:

The reason of reboot is rst:0x8 (TG1WDT_SYS_RST) → Timer Group 1 Watchdog Timer triggered a system reset
But I have no backtrace or core dump to uart.
I don't use interrupt directly, and the esp32 is using wifi, uart, BLE, modbus.

Using xtensa-esp32s3-elf-addr2line -pfiaC -e build/gateway-esp32.elf 0x42004bcf I found the last line executed in panic_handler.c line 146.

Code: Select all

static void panic_handler(void *frame, bool pseudo_excause)
{
    panic_info_t info = { 0 };

    /*
     * Setup environment and perform necessary architecture/chip specific
     * steps here prior to the system panic handler.
     * */
    int core_id = esp_cpu_get_core_id();

    // If multiple cores arrive at panic handler, save frames for all of them
    g_exc_frames[core_id] = frame;

#if !CONFIG_ESP_SYSTEM_SINGLE_CORE_MODE
    // These are cases where both CPUs both go into panic handler. The following code ensures
    // only one core proceeds to the system panic handler.
    if (pseudo_excause) {
#define BUSY_WAIT_IF_TRUE(b)                { if (b) while(1); }
        // For WDT expiry, pause the non-offending core - offending core handles panic
        BUSY_WAIT_IF_TRUE(panic_get_cause(frame) == PANIC_RSN_INTWDT_CPU0 && core_id == 1);
        BUSY_WAIT_IF_TRUE(panic_get_cause(frame) == PANIC_RSN_INTWDT_CPU1 && core_id == 0);

        // For cache error, pause the non-offending core - offending core handles panic
        if (panic_get_cause(frame) == PANIC_RSN_CACHEERR && core_id != esp_cache_err_get_cpuid()) {
            // Only print the backtrace for the offending core in case of the cache error
            g_exc_frames[core_id] = NULL;
            panic_print_str("Guru Cache Error");
            while (1) {			//line 146!!!!!
                ;
            }
        }
    }

I can't replicate the error and i can't understand the state of esp32 before the panic handler.

I try :
- stack corruption
- while(1) inside main task
- division by 0
- memcpy to null position

What could cause the TG1WDT_SYS_RST at this early stage?
Could a peripheral (e.g., PSRAM, SPI, or power instability) trigger this WDT reset?

Posted: **Sun Nov 09, 2025 11:17 pm**

can't replicate the error and i can't understand the state of esp32 before the panic handler.

When a task watchdog alert or interrupt watchdog alert occurs, it will transition to Halt instead of Reset.

ESP32 Forum

Watchdog Reset (TG1WDT_SYS_RST)

Watchdog Reset (TG1WDT_SYS_RST)

Re: Watchdog Reset (TG1WDT_SYS_RST)