Raspberry PI and capacitive sensor example
In this example we will connect a capacitive sensor to a GPIO pin on our Raspberry PI, when we touch the sensor we will display a message to the user. A practical use may be a touch activated lamp.
This is the sensor we used which is low cost and available from multiple places
Here is a schematic representation, fairly straightforward
Lets look at the code, this is written in python and requires the RPi library to be installed, I recently downloaded NOOBs, installed RAspbian and python and this library were available by default.
Open the terminal and type in the following
Wait for IDLE to open, then click File > New to open a new window. Or you can use CTRL + N.
Now enter the following code
import time import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setup(23, GPIO.IN) while True: pressed = GPIO.input(23) if padPressed: print "cap pressed" time.sleep(0.5)
Click File > Save when you are finished (Ctrl + S).
To run your program, click Run > Run (Ctrl + F5), your should output like the following