Peter Fuss has informed me of a program which simplifies interfacing an Arduino display with Jeehell FMGS. The software by Peter Piper is designed to be used to simulate the ADIRS display panel by reading the data and sys switch from the avionics overhead panel and outputting appropriately.
More information available on the FlightX forum (German).
Software and direct download now available on the FMGS Forum. Resource section updated.