ESP32 WDT Interrupt Handler Not Registered

In this tutorial, you'll learn about ESP32 WDT Interrupt Handler Not Registered. We cover key concepts, practical examples, and best practices.

The Problem

ESP32 watchdog timer interrupt handler is not called before system reset.

Quick Fix

Wrong

// No WDT handler registered
// System just resets without warning

Sudden reboot. No debug information about WDT trigger.

Right

void IRAM_ATTR wdtISR(void* arg) {
  // Save reset reason to RTC memory
  RTC_DATA_ATTR int wdtCount;
  wdtCount++;
  esp_default_wdt_handler(arg);
}
timer_config_t config = { /* ... */ };
timer_isr_register(TIMER_GROUP_0, TIMER_0, wdtISR, NULL, 0, NULL);

WDT triggered. Count saved to RTC memory. System restarts with reason code.

Prevention

Register ISR before WDT timeout. Save debug info to RTC memory before reset. Use panic handler to capture backtrace. Set esp_task_wdt_config.trigger_panic=true for crash dump. Analyze serial output for WDT reason.

DodaTech engineers apply these same patterns across Doda Browser, DodaZIP, and Durga Antivirus Pro for production IoT reliability.

FAQ