PLaying with Raspberry Pi GPIOs + LED

demo.php

<?php
namespace PhpGPioDemo;

require(__DIR__.'/vendor/autoload.php');

use PhpGpio\Gpio;
use PhpGpio\GpioInterface;

$mapping = [
    4 => 'red',
    17 => 'yellow',
    27 => 'red',
    5 => 'yellow',
    6 => 'red',
    13 => 'yellow',
    19 => 'red',
    12 => 'yellow',
    16 => 'red',
];

$gpio = new Gpio($pins = array_keys($mapping));

foreach ($pins as $pin) {
    $gpio->setup($pin, GpioInterface::DIRECTION_OUT);
}

$effects = [
    // 0 Blink
    function() use ($gpio, $pins, $mapping) {
        for ($i = 0; $i < 9; $i++) {
            foreach ($pins as $pin) {
                $gpio->write(
                    $pin,
                    $i % 2 ? GpioInterface::IO_VALUE_ON : GpioInterface::IO_VALUE_OFF
                );
            }
            usleep(100000);
        }
    },

    // 1 Blink alternate colors
    function() use ($gpio, $pins, $mapping) {
        $cColor = 'red';
        for ($i = 0; $i < 9; $i++) {
            $cColor = $i % 2 ? ($cColor == 'yellow' ? 'red' : 'yellow') : $cColor;
                foreach ($mapping as $pin => $color) {
                if ($color == $cColor) {
                    $gpio->write(
                        $pin,
                        $i % 2 ? GpioInterface::IO_VALUE_ON : GpioInterface::IO_VALUE_OFF
                    );
                }
            }
            usleep(200000);
        }
    },

    // 2 Chaser
    function() use ($gpio, $pins, $mapping) {
        for ($i=0; $i<2; $i++) {
            foreach ($pins as $pin) {
                $gpio->write($pin, GpioInterface::IO_VALUE_ON);
                usleep(50000);
                $gpio->write($pin, GpioInterface::IO_VALUE_OFF);
            }

            $pin = end($pins);
            do {
                $gpio->write($pin, GpioInterface::IO_VALUE_ON);
                usleep(50000);
                $gpio->write($pin, GpioInterface::IO_VALUE_OFF);
            } while ($pin = prev($pins));
        }
    },

    // 3 Beginning to end, then back to begining
    function() use ($gpio, $pins, $mapping) {
        foreach ($pins as $pin) {
            $gpio->write($pin, GpioInterface::IO_VALUE_ON);
            usleep(50000);
        }

        $pin = end($pins);
        do {
            $gpio->write($pin, GpioInterface::IO_VALUE_OFF);
            usleep(50000);
        } while ($pin = prev($pins));
    },

    // 4 Long chaser
    function() use ($gpio, $pins, $mapping) {
        foreach ($pins as $pin) {
            $gpio->write($pin, GpioInterface::IO_VALUE_ON);
            usleep(50000);
        }

        foreach ($pins as $pin) {
            $gpio->write($pin, GpioInterface::IO_VALUE_OFF);
            usleep(50000);
        }
    },

    // 5 Random on/off
    function() use ($gpio, $pins, $mapping) {
        $on = [];
        for ($i=0 ; $i < 10 ; $i++) {
            $pin = mt_rand(0, count($pins)-1);

            if (($index = array_search($pin, $on)) !== false ){
                unset($on[$index]);
                $newState = GpioInterface::IO_VALUE_OFF;
            } else {
                $newState = GpioInterface::IO_VALUE_ON;
                $on[] = $pin;
            }

            $gpio->write($pins[$pin], $newState);
            usleep(50000);
        }
        clear();
    }
];

function clear() {
    global $pins, $gpio;
    foreach ($pins as $pin) {
        $gpio->write($pin, GpioInterface::IO_VALUE_OFF);
    }
}

function effect($id) {
    global $effects;
    call_user_func($effects[$id]);
}

$unexport = function () {
    global $gpio;
    $gpio->unexportAll();
    exit;
};

declare(ticks=1);
pcntl_signal(SIGINT, $unexport);
pcntl_signal(SIGTERM, $unexport);

if (isset($argv[1]) && is_numeric($argv[1]) && $argv[1] >= 0 && $argv[1] < count($effects)) {
    do {
        effect($argv[1]);
    } while (true);
} else {
    do {
        effect(mt_rand(0, count($effects) - 1));
    } while (true);
}