Skip to main content

GPIO Driver

These functions allow you to configure and interact with GPIO pins on the ESP32 from within a WebAssembly module.

Set GPIO Level​

result = wasm_gpio_set_level(gpio_num, level);
  • Parameters:
    • gpio_num: GPIO pin number.
    • level: GPIO level (e.g., 0 for LOW, 1 for HIGH).
  • Returns: ESP_OK on success, or an error code on failure.
  • Description: Sets the output level of a GPIO pin.

Reset GPIO Pin​

result = wasm_gpio_reset_pin(gpio_num);
  • Parameters:
    • gpio_num: GPIO pin number.
  • Returns: ESP_OK on success, or an error code on failure.
  • Description: Resets the GPIO pin to its default state.

Set GPIO Direction​

result = wasm_gpio_set_direction(gpio_num, mode);
  • Parameters:
    • gpio_num: GPIO pin number.
    • mode: GPIO mode (e.g., GPIO_MODE_INPUT, GPIO_MODE_OUTPUT, GPIO_MODE_INPUT_OUTPUT).
  • Returns: ESP_OK on success, or an error code on failure.
  • Description: Configures the direction of a GPIO pin.

Example Usage​

Configure GPIO and Set Level​

// Set GPIO 2 as output
result = wasm_gpio_set_direction(2, GPIO_MODE_OUTPUT);
if (result != ESP_OK) {
    println("Failed to set GPIO direction");
    return;
}

// Set GPIO 2 to HIGH
result = wasm_gpio_set_level(2, 1);
if (result != ESP_OK) {
    println("Failed to set GPIO level");
    return;
}

// Reset GPIO 2 to its default state
result = wasm_gpio_reset_pin(2);
if (result != ESP_OK) {
    println("Failed to reset GPIO pin");
    return;
}

Explanation​

  1. Set Direction:

    • Configures GPIO 2 as an output pin using wasm_gpio_set_direction.

  2. Set Level:

    • Sets the GPIO pin to HIGH using wasm_gpio_set_level.

  3. Reset Pin:

    • Resets the GPIO pin to its default state using wasm_gpio_reset_pin.

This example demonstrates how to configure and control GPIO pins using the provided bindings.