Caranado C-172 key assignments

I've recently begun my RW flight training in a C-172, and it's been wonderful having the Carenado 172N at home for lesson reviews.There are a few functions I'd like to map to my keyboard, but haven't been been able to figure out how.Does anyone know how I can map the following key commands in FSUIPC or the sim itself:- Transponder selection (off, standby, on, alt) - COM1 off/on volume control- COM1 squelch controlThanks for any help,Charlie