I’m not quite sure why anyone would want to use the sort-of Arduino-compatible HamStack — billed as a microcontroller platform especially for amateur radio operators —in preference to developing amateur radio applications for Arduino, but chacun à son thingy. The PIC-based [I'd link to the PIC info page, but Microchip is giving me an internal server error] platform may have a few more IO pins than the stock Arduino, but:
- development tools are expensive
- there’s no cross-platform support
- no direct USB support, either.
Some folks may already have gone to the expense of a PIC-based toolchain, but for beginners, it could be prohibitive. Maybe better to develop and improve radio applications for Arduino.