Simple APM / Telemetry / Arduino Connection

I am new to APM, and have what appears a simple use case. I just want a simple audible alarm for plane aerobatics training around wings level. At its simplest one beep for inside wing down more than x degrees, two beeps for up more than x degrees. Should be a simple interpretation of Roll axis data. Aim is to be independent of radio equipment so can be easily added to any plane - hence thinking Arduino Uno or similar at ground end for simple / robust interpretation and audio feedback.

Can anyone point me to any existing pieces of code or frameworks for capturing / parsing data into Arduino at ground end. Telemetry hasn’t turned up yet - can you also guide me on whether the bit stream is given (sends everything) or is it an API like call to just get what I need?


On further reading it seems I might be better to consider a Raspberry Pi at the ground end, as there appear to be better developed MavLink libraries and code bases to help with interpretation. Is that a better track?