Multiple SBUS RCIN/MAV inputs to implement C2 rendundancy & failover, possibile?

Hi all,

since i’m experimenting long range flights (on theory, for now) i’m wondering on how to manage multiple SBUS inputs or MAV overrides, to better implement failovers and have “step by step” range approach, experimenting different concurrent datalinks. That’s my idea:

  • FC would accept multiple SBUS inputs, to be configured on SerialXX as sbus (apart RCIN which has it by design) or mav overrides
  • Arducopter firmware would read them all, creating a priority list with a given fall-back order, for example:
    • RCIN is on top
    • (implicit) SerialXX would be second, third etc depending on reverse order (e.g. serial2 is over serial3 which is over serial4, etc. Of course, serials not configured for C2 would be skipped). Alternatively, it could be defined an explicit priority list through purpose made new params.
  • user should be informed on which C2 channel the FC is using, in real time

Then i would put different SBUS compatible receivers, for example, a Frsky X8R, a RFD900, Crossfire on mav override, etc). At startup every datalink is working with RSSI 100%.
While flying, system relies on the RCIN input (or mav override, if configured to do so) until its signal is lost, then switched seamlessly (with a notification of course) to the first working input following the priority list. This is a proposal, for sure it’s not the only or the best failover law.
Let me know if ardupilot can/could do it already (even with LUA), or maybe i can open a PR.

EDIT: i just found this: