The hardware is ready, now you can access all this functionality from Raspberry Pi Zero. First, install the library associated with the control board, found at http://www.monkmakes.com/?page_id=698 and perform the following steps:
wget https://github.com/simonmonk/raspirobotboard2/raw/master/python/dist/rrb2-1.1.tar.gz. This will retrieve the library.
tar -xzf rrb2-1.1.tar.gz. This will unarchive the files.
cd rrb2-1.1. This will change the directory to the location of the files.
sudo python setup.py install. This will install the files.
Now you'll create some Python code that will allow you to access both the drive motor and the steering motor. The code will look similar to the following ...