One thing that separates the Pi from other the rest of Single Board Computer is its ability to use the GPIO (General Purpose Input/Output) pins which can be switched as HIGH or LOW to control any external devices. All you will need is a GPIO breakout board and a few jumper cable to begin with. Here I’ve used a female-to-male connector to complete the job.
The quickest way to get started is to make use of python which comes pre-installed in all the OS images. Obtain the RPi.GPIO library and copy the gz tar ball to your SD card. Open the terminal and browse to the extracted directory containing the RPi.GPIO library.
$ sudo python setup.py install to install the library.
Note: As the OS is multitasking and not Real-time unlike Arduino there may possibly be jitters depending on CPU load.
Based on the library I have written a easy code to turn ON and turn OFF the light emitting diode after a delay of 1 sec (1000ms) each. The diode blinks 50 times.
You can use nano text editor to write the code on the console or copy paste the code and save it as a blink.py file and upload the file to your raspberry pi
import RPi.GPIO as GPIO import time # blinking function def blink(pin): GPIO.output(pin,GPIO.HIGH) time.sleep(1) GPIO.output(pin,GPIO.LOW) time.sleep(1) return # to use Raspberry Pi board pin numbers GPIO.setmode(GPIO.BOARD) # set up GPIO output channel GPIO.setup(11, GPIO.OUT) # blink GPIO17 50 times for i in range(0,50): blink(11) GPIO.cleanup()
One you have the file saved just run the python code as follows
sudo python blink.py