ESP8266 Button

This button library simplifies the implementation of GPIO based callbacks on the ESP8266. The button object is assigned to a GPIO. On assignment the object automatically detects and stores the resting state of the pin. Users can assign callbacks to be run when the button is pressed or held. The duration that distinguishes a press from a hold can be set by the user. Debouncing is handled by the library, with the debounce interval being user assignable.

Callbacks are run within an ISR, thus ISR best practices apply. Callbacks should be kept short, and volatile should be used when necessary.

Requirements

This library makes use of <FunctionalInterrupt.h> to attach std::function<void()> callbacks through attachInterrupt(). This is currently available only in the stage version of the ESP8266 Arduino framework.

Methods

Constructor

Button b(const gpio_num_t); // Construct a button on a given GPIO

Setting callbacks

Callbacks are passed as std::function<void()> objects and are copied into the Button object.

b.pressCallback([]() {
    // Do something on button press
});

b.holdCallback([]() {
    // Do something on hold
});

Setting timings

// Holding longer than 3000 ms will trigger a button hold callback
b.holdDuration(3000); // Default 5000

// Ignore button events less than 200 ms apart (debouncing)
b.refractoryPeriod(200);  // Default 100