Book Image

BeagleBone Essentials

By : Rodolfo Giometti
Book Image

BeagleBone Essentials

By: Rodolfo Giometti

Overview of this book

Table of Contents (18 chapters)
BeagleBone Essentials
About the Author
About the Reviewers

Managing an LED in PHP

Now it's time to see how to manage our LED using the PHP language.

There are two different possibilities to do this: the first one is to use the LAMP (Linux-Apache-MySQL-PHP) system we set up in The LAMP suite section of Chapter 1, Installing the Developing System, while the second one is to use the PHP built-in web server.

The LAMP solution

This is the easiest and most classic way to implement a common web application. We just need a PHP script where we can implement our LED management. So let's start with writing some code!

In the first step, we must create a file named turn.php in the /var/www/ directory of the BeagleBone Black with the following content:

        # 1st part - Global defines & functions
        define("value_f", "/sys/class/gpio/gpio66/value");

        # 2nd part - Get the current led status
        $led_status = intval(file_get_contents(value_f));

        # 3rd part - Render the led status by HTML code