ESP32 Interrupt Flags Incorrect for Use Case

In this tutorial, you'll learn about ESP32 Interrupt Flags Incorrect for Use Case. We cover key concepts, practical examples, and best practices.

The Problem

ESP32 interrupt does not fire or behaves unexpectedly due to wrong interrupt flags.

Quick Fix

Wrong

esp_intr_alloc(source, 0, isr, NULL, &h);  // No flags, low pri

Interrupt fires but latency is high or missed events occur.

Right

esp_intr_alloc(
  ETS_GPIO_INTR_SOURCE,
  ESP_INTR_FLAG_IRAM | ESP_INTR_FLAG_LEVEL3,
  isr,
  NULL,
  &h
);
// Level 1 = lowest priority (safe)
// Level 3 = medium priority
// Level 6 = highest (use with caution)

Interrupt with correct priority. Low latency. No missed events.

Prevention

Use lowest priority that meets latency requirement. Always add ESP_INTR_FLAG_IRAM for levels > 2. Use ESP_INTR_FLAG_SHARED for multiple sources. Check flag compatibility with interrupt source.

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

FAQ