QR Codes Using Onion Omega

QR Codes are two dimensional barcodes that can easily be scanned by smartphones.

In this tutorial, we'll go through how you can use Python to encode text into a QR Code and display it on your OLED Expansion.

Overview

Tutorial Difficulty: Beginner

Time Required: 10 minutes

Required Materials:

• The Omega

• The Expansion Dock

• OLED Expansions

Useful Experience:

• Using the OLED Expansion

• Using Python

Installing Required Packages

We will need to have support for git, Python, and the Onion OLED Expansion Python Module.

opkg update
opkg install git git-http python-light python-codecs pyOledExp

Downloading the Code

Now we need to download the Python code that actually does all the work:

cd /root
git clone https://github.com/OnionIoT/oledQrCodeGenerator.git

Running the Code

Finally, we get to make some QR codes! Navigate into the repo directory:

cd oledQrCodeGenerator

And run the program, the argument to the script is the text that will be encoded in the QR code pattern:

root@Omega-18C2:~/oledQrCodeGenerator# python main.py 'Wow, my first QR Code'
> Encoding 21 characters
> Generated QR Code: 31x31 pixels
> Doubled QR Code size: 62x62
> Initializing display
> Setting display mode to inverted
> Writing buffer data to display

This will encode the data and display the resulting QR code on the OLED Expansion:

Using the code as a Python Module (Optional)

You can use the oledQrCodeGenerator module in your own Python projects!

Example Code

import oledQrCodeGenerator
oledQrCodeGenerator.dispQrCode('Hello!')

Note that your Python script will have to be in the same directory as oledQrCodeGenerator in order for it to work properly.

Reading QR Codes

You can now use a smartphone to read the QR code on the OLED:

• On Android, we've used the QR Code Reader and QR Barcode Scanner apps successfully

• On iOS, we've had success with the QR Reader App

Happy hacking!

Acknowledgements

The code in the qrcode directory is a stripped-down version of lincolnloop's python-qrcode repo:

https://github.com/lincolnloop/python-qrcode

The rest of the code is home grown by the Onion team :)

Original Wiki Page

The original guide page is available at:

https://wiki.onion.io/Projects/OLED-QR-Code-Generator