This snippet is intended to be the hello world equivalent for working with the raspberry pi gpio with node.js. This simply flashes an LED connected to pin 7 based on the duration.

simple_gpio_with_javascript.js

/*
Requires:
- pi-gpio
- gpio-admin

This snippet is intended to be the hello world equivalent for working
with the raspberry pi gpio with node.js.  This simply flashes an LED
connected to pin 7 based on the duration.
*/

var gpio = require("pi-gpio");

function flashLED(pin, duration) {
    return setInterval(function() {
        gpio.open(pin, "output", function(err) {
            gpio.write(pin, 1, function() {
                setTimeout(function() {
                    gpio.write(pin, 0, function(err) {
                        gpio.close(pin);
                    });
                }, duration/2);
            });
        });
    }, duration);
}

var intervalID = flashLED(7, 500);

setTimeout(function() {
    clearInterval(intervalID);
}, 60000);

simple_gpio_with_python.py

# Requires: RPi.GPIO

import RPi.GPIO as GPIO

from threading import Event, Thread, Timer


class ImprovedThread(Thread):
    def __init__(self, *args, **kwargs):
        super(ImprovedThread, self).__init__(*args, **kwargs)
        self._stopEvent = Event()

    def stop(self):
        self._stopEvent.set()

    def is_stopped(self):
        return self._stopEvent.isSet()

    def wait(self, duration):
        self._stopEvent.wait(duration);


class LEDFlasher(ImprovedThread):
    def __init__(self, pin, duration):
        super(LEDFlasher, self).__init__(target=self._flashLED)
        self.setDaemon(True)

        self._pin = pin
        self._duration = duration
        self._state = False

        GPIO.setmode(GPIO.BOARD)
        GPIO.setup(self._pin, GPIO.OUT)

        self.start()

    def _flashLED(self):
        while not self.is_stopped():
            GPIO.output(self._pin, self._state)
            self._state = not self._state
            self.wait(self._duration/2)

flasher = LEDFlasher(7, 0.5)
Timer(60, flasher.stop).start()

flasher.join()

GPIO.cleanup()