Getting Started Example with the Onion Omega & Python

In this quick tutorial you’ll learn how to control the in-built LED in the expansion dock using Python.

Time required: < 5 minutes

Python Example


First you’ll need to install python & also git for this example. To do this run the following commands from the console

opkg update
opkg install python-light git git-http

This will take a few moments, once complete let’s grab the example code from GitHub by running these commands:

cd /root
git clone

Running the Example

Excellent, let’s now change directories and run the example python script.

cd OmegaGPIO 

The RGB LED on your expansion dock will now be rotating through red, green & blue.

Neat eh?

Using the GPIO Functions

Take a look at file to see the available functions that can be used in your own Python projects.

Using a GPIO as Output

Here is a small sample of code that sets GPIO13 to HIGH and then LOW 5 seconds later:

import omega_gpio
import time

# initialize the pin
gpioNum = 13

# set the pin to HIGH
omega_gpio.setoutput(gpioNum, 1)

# wait 5 seconds and set to LOW
omega_gpio.setoutput(gpioNum, 0)

# release the pin

Using a GPIO as Input

This sample of code shows how to read and print the input value of a GPIO every 5 seconds for a minute:

import omega_gpio
import time

# initialize the pin
gpioNum = 26

# perform 12 reads, each 5 seconds apart
for i in range (0, 12):
	print 'GPIO%d value: %d'%(gpioNum, omega_gpio.readinput(gpioNum) )

# release the pin

Further Reading

A huge hat-tip to Brian Piersel for posting this example code in the community forums.

And a thank you from Onion to Matthew Ogborne for writing this tutorial.

More details on the Onion Omega GPIO Pins can be found here.