Mcu

GPIO initialization on the ESP32 in ESP-IDF

Electronics

This is just a quick post on how not to initialize a GPIO in ESP-IDF. A tutorial on Embedded Explorer discusses GPIO use in ESP-IDF and suggests initialization in this way:

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"

#define LED_PIN     GPIO_NUM_32
#define BUTTON_PIN  GPIO_NUM_36

void app_main(void)
{
   gpio_set_direction(LED_PIN, GPIO_MODE_OUTPUT);   
   gpio_set_direction(BUTTON_PIN, GPIO_MODE_INPUT);
   
   while(1) {       
      if (gpio_get_level(BUTTON_PIN) == 0) {  // If button is pressed
         gpio_set_level(LED_PIN, 1);         // Turn the LED on
      } else {
         gpio_set_level(LED_PIN, 0);         // Turn the LED off
      }
      
      vTaskDelay(1); // Add 1 tick delay (10 ms) so that current task does not starve idle task and trigger watchdog timer
   }
}

This of course works, but I wanted to clear up matters because I think this takes some major shortcuts. Here is what I would suggest instead:

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