Raspberry Pi 3 Starter Kit Hookup Guide

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Contributors: MTaylor
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Reading Inputs and Toggling the LEDs

This section contains instructions for getting the software necessary to compile programs that use the GPIO, then redirects to our Raspberry gPIo tutorial.

Getting WiringPi for Using C++

The WiringPi library is required to operate the GPIO with C++. There are two methods to get it, mentioned below. Either way, it will have to be built before use.

Get From the WiringPi

Note: Wiring Pi is now pre-installed with standard Raspbian systems. The instructions from the official WiringPi homepage are now depreciated. The original wiringPi source "git://git.drogon.net/wiringPi" is not available.

Wiring Pi is previously not included with early versions of Raspbian. This required users to download and install it. Luckily, Wiring Pi is included in standard Raspbian systems. If you are looking to update using a mirrored Wiring Pi with small updates to support newer hardware, we recommend checking out this GitHub repository.

You'll need git (may be installed by default). If git is not installed, enter the following into the command line.

language:bash
sudo apt-get install git-core

We highly recommend using Git to download the latest version. To check what version you have, enter the following command.

language:bash
gpio -v

If you receive an output similar to to the following with the Unknown17, you'll want to update WiringPi on a Raspberry Pi 4 or above.

language:bash
gpio version: 2.50
Copyright (c) 2012-2018 Gordon Henderson
This is free software with ABSOLUTELY NO WARRANTY.
For details type: gpio -warranty

Raspberry Pi Details:
  Type: Unknown17, Revision: 02, Memory: 0MB, Maker: Sony
    * Device tree is enabled.
    * --> Raspberry Pi 4 Model B Rev 1.2
    * This Raspberry Pi supports user-level GPIO access.

Enter the following to remove the wiringPi and configuration files.

language:bash
sudo apt-get purge wiringpi

Then type the following for the Pi to remove all locations that remember wiringPi.

language:bash
hash -r

As long as you have Git installed, these commands should be all you need to download and install Wiring Pi.

language:bash
git clone https://github.com/WiringPi/WiringPi.git

This will make a folder in your current directory called WiringPi. Head to the Wiring Pi directory.

language:bash
cd WiringPi

Then pull the latest changes from the origin.

language:bash
git pull origin

Then enter the following command. The ./build is a script to build Wiring Pi from the source files. This builds the helper files, modifies some paths in Linux and gets WiringPi ready to rock.

language:bash
./build

At this point, the library should work. Run the gpio command shown below to view some information about the wiringPi version and the Pi that it is running on.

language:bash
gpio -v

Entering the following command will draw a table illustrating the configuration for the pins in the 40-pin connector.

language:bash
gpio readall

Getting Python

Raspbian comes with Python pre-installed. Continue to the gPIo tutorial to find out how to use it.

Using the GPIO.

This excellent tutorial covers all the INs, OUTs, and PWMs of GPIO with the Pi platform.

Raspberry gPIo

October 29, 2015

How to use either Python or C++ to drive the I/O lines on a Raspberry Pi.