Raspberry Pi Cookbook, 4th Edition

Chapter 11. Controlling Hardware

11.0 Introduction

In this chapter, you come to grips with the control of electronics through the Raspberry Pi’s general-purpose input/output (GPIO) connector.

Most of the recipes require the use of a solderless breadboard and male-to-female and male-to-male jumper wires (see Recipe 10.9). To maintain compatibility with older 26-pin Raspberry Pi models, all the breadboard examples here use only the top 26 pins common to both GPIO layouts (see Recipe 10.1).

For a kit of parts, and breadboard, that are suitable for many of the recipes in this chapter, take a look at the Project Box 1 kit for Raspberry Pi.

11.1 Connecting an LED

Problem

You want to know how to connect an LED to the Raspberry Pi.

Solution

Connect an LED to one of the GPIO pins using a 470Ω or 1kΩ series resistor to limit the current. To make this recipe, you will need the following:

• Breadboard and jumper wires (see “Prototyping Equipment and Kits”)

• 470Ω resistor (see “Resistors and Capacitors”)

• LED (see “OptoElectronics”)

Figure 11-1 shows how you can wire this LED using a solderless breadboard and male-to-female jumper leads. The LED has positive and negative leads. The positive lead is the longer and will be the one on the same row as the resistor in Figure 11-1.

The resistor shown is a 470Ω resistor, which will make the LED shine brightly without drawing so much current that the Raspberry Pi could be damaged.

Figure 11-1. Connecting an LED to a ...