I’m a bit stuck here. I can’t get my F765/R9MM to send telemetry to my transmitter. SmartPort is connected to SERIAL1, protocol is Frsky SPort (4). I’ve tried it with Plane 4.0.5 and 4.1.0_dev. Tried using both the uninverted and inverted SmartPort connection, but since it’s an F7 this shouldn’t matter anyway. Tried manually setting the SERIAL1 options to inverted Tx, no luck.
We can exclude any wiring or hardware issues, since it works without issue with iNav. I’ve got a similar configuration (different FC though) on a quad where it works as well.