This guide will show you how to turn your PiFace CAD into a random number generator. First download the randomCAD files from github by opening a Terminal and typing
git clone https://github.com/thomasmacpherson/randomCAD.git
Move into the newly created folder
Run randomCAD with the command
You will see the PiFace CAD's backlight come on and text saying "Random number from 000 > 000→"
Flick the rocker switch to select the number in the range you wish to change, once there press in the rocker switch and flick it to the number you want. To accept this number press in the rocker switch again. Repeat this until you have set the range of your random number, eg:256 > 512. Then flick the rocker switch so the cursor is under the
→. Press in the switch a final time and your random number will appear on the second line of the LCD screen.