rf communication pic
hi we developed our own RF protocol based on the free S.N.A.P protocol
w*w.hth.com/snap/
However i think is to big to fit in a pic it was designed to run on avr mega 323 and mega 128 the latter being for a pc link and the 323 used for a handheld monitor unit and a loadcell telemetry unit.
it uses a low level hard ware driver so we could drop in new radio technologies and when they become available so you should be able to adapt it to your device. it then has a link layer which holds the modified snap protocol and then a high level layer which supports our command structure and plug and play capabilities of the devices.
i could send you some of the code you may only need the lower 2 layers and a state machine for your app not sure what you wish it to do.