Book Image

Raspberry Pi Zero Cookbook

Book Image

Raspberry Pi Zero Cookbook

Overview of this book

The Raspberry Pi Zero, one of the most inexpensive, fully-functional computers available, is a powerful and revolutionary product developed by the Raspberry Pi Foundation. The Raspberry Pi Zero opens up a new world for the makers out there. This book will give you expertise with the Raspberry Pi Zero, providing all the necessary recipes that will get you up and running. In this book, you will learn how to prepare your own circuits rather than buying the expensive add–ons available in the market. We start by showing you how to set up and manage the Pi Zero and then move on to configuring the hardware, running it with Linux, and programming it with Python scripts. Later, we integrate the Raspberry Pi Zero with sensors, motors, and other hardware. You will also get hands-on with interesting projects in media centers, IoT, and more.
Table of Contents (17 chapters)
Raspberry Pi Zero Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Interfacing any resistive sensor on GPIO


Resistive sensors are devices whose resistance changes when the sensor's input is altered. A photoresistor will change based on the amount of light, and a thermistor's resistance changes with temperature. With a simple circuit, you can configure your GPIO to read changes in a resistive sensor's values.

Getting ready

For this recipe, I used a photoresistor as they are the easiest ones to change values on. Any two-lead resistive sensor will work for this recipe. You'll also need a 1uF electrolytic capacitor.

How to do it...

  1. Configure the following circuit and wire it to the Raspberry Pi:

  2. Using RPi.GPIO again, we can put together a simple program that tracks our sensor. Create photoresitor.py in the ch9 directory with the following code:

        #!/usr/bin/env python 
        # Raspberry Pi Zero Cookbook 
        # Chapter 9 - Analog Sensors 
        import RPi.GPIO as GPIO 
        import sys 
        import time 
        import os 
        #GPIO.setwarnings(False) 
        GPIO.setmode(GPIO...