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.
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.
Configure the following circuit and wire it to the Raspberry Pi:
Using
RPi.GPIO
again, we can put together a simple program that tracks our sensor. Createphotoresitor.py
in thech9
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...