gs-arduino/BlinkPlugin.php

<?php

if (!defined('GNUSOCIAL')) {
    exit(1);
}

require_once("util/arduino.php");

class BlinkPlugin extends Plugin
{
    const VERSION = '0.0.1';


    public function onPluginVersion(array &$versions)
    {
        $versions[] = ['name' => 'Blink',
            'version' => self::VERSION,
            'author' => 'Hackers at Porto',
            'homepage' => 'https://notabug.org/',
            'description' => _m('Plugin that switches a led when a note asks for it.')];
        return true;
    }

    public function onStartNoticeSave(Notice $notice)
    {
        $on  = preg_match(".*light.*", notice.getContent());
        $off = preg_match(".*darkness.*", notice.getContent());
        arduino.send($on << 1 | $off << 2);
    }
}