I have a spare arduino mega in the home office for this task. You don’t need a motor shield or anything else attached to it. A small edit in the firmware before you upload it to the mega and you can run GC. Be aware that the Arduino IDE stores that change without asking, so I don’t do this in the workshop. Just to make sure that I’m not wondering for hours why the Maslow is not working 
The top terminal is the command window GC is started from. The second is a ‘tail’ on the log file (Linux). I use vlc to record my desctop 12f/sec.