Getting acquainted with the GPIO
Before we embark on connecting lots of things to our Pi board, it might be a good idea to just get acquainted with the GPIO through a couple of simple projects that will help us understand how to interact with the digital I/O pins using shell scripts.
Let there be light
This simple little project shows how to connect a GPIO output to an LED, and switch it on and off using shell commands.
The following diagram shows how to connect up the circuit using a breadboard:
The pretty diagram that you just saw was produced using a free software tool from fritzing, which is an open-source hardware initiative to make electronics ...