trf24g RF module code

This is code for using an nRF2401-based transceiver module

Files:

trf24g.c -- Routines for using the device
trf24g.h -- Header file to include for using the device
trf24g_hw.h -- mcu-specific tweakable bits (seperated out to make porting easier)
spin_delay.h -- fairly accurate uS/mS busy-loop delay routines
rf_serial_test.c -- messy test example of using the comms (for example only; the UART routines it uses aren't included... really just to be used to understand how to use the interface)