onoff/examples/wait-for-interrupt.js

GPIO access and interrupt detection with Node.js

'use strict';

const Gpio = require('../onoff').Gpio; // Gpio class

// Export GPIO4 as an interrupt generating input with a debounceTimeout of 10
// milliseconds
const button = new Gpio(4, 'in', 'rising', {debounceTimeout: 10});

console.log('Please press the button on GPIO4...');

// The callback passed to watch will be invoked when the button connected to
// GPIO4 is pressed
button.watch((err, value) => {
  if (err) {
    throw err;
  }

  console.log('Button pressed!, its value was ' + value);

  button.unexport(); // Unexport GPIO and free resources
});