- Makefile: removed limitation to Ben and added host build
- atusb.c: atusb-specific acquisition and calculations
- atrf-xtal.h (do_atusb): interface to atusb.c
- atrf-xtal.c (atben, atusb, main): added switch to board-specific driver
- atrf-xtal.c (usage, main): added support for atusb
- Makefile (DIRS): added atrf-xtal
- atrf-xtal/Makefile: build atrf-xtal for the Ben or do nothing elsewhere
- atrf-xtal/atrf-xtal.h, atrf-xtal/atrf-xtal.c: diagnostic utility to
determine the transceiver's crystal frequency
- atrf-xtal/atben.c: dirty low-level driver for ATBEN