DashBoard has a Midi Controller interface...It allows tieing of Midi commands to actions in DashBoard. We use a Midi USB Audio Controller to act as a hard panel for Graphite Audio Mixer.
Buttons fire off "notes" and you can link those to trigger events which would fire the button that you assign that trigger event to. I guess you could get a Serial to USB Midi cable and try that.
Or maybe do it with an Arduino if you can find example code for accepting Midi commands...I have seen making it send Midi so I am sure something is out there that would make it look like a USB Midi HID device.
#Carbonite