ESP32 Timer Group Conflict with Other Peripheral

In this tutorial, you'll learn about ESP32 Timer Group Conflict with Other Peripheral. We cover key concepts, practical examples, and best practices.

The Problem

ESP32 timer fails because the timer group is already in use by another peripheral.

Quick Fix

Wrong

timer_init(TIMER_GROUP_0, TIMER_0, &config);
// TIMER_GROUP_0 may conflict with PWM channel

ESP_ERR_INVALID_ARG. Timer group allocation fails.

Right

// Check which timer groups are available
// Group 0: timer 0-3 (shared with LEDC)
// Group 1: timer 0-3 (separate from LEDC)
timer_config_t config = { /* ... */ };
esp_err_t err = timer_init(TIMER_GROUP_1, TIMER_0, &config);
if (err == ESP_OK) {
  Serial.println("Timer group 1 initialized");
} else {
  Serial.printf("Failed: %s\n", esp_err_to_name(err));
}

Timer group 1 initialized
(Timer running without conflicts)

Prevention

Use TIMER_GROUP_1 if LEDC/PWM is using group 0. Check peripheral conflicts in the ESP32 technical reference manual. Free timer groups with timer_deinit(). Use different timers for different frequency domains.

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

FAQ