Frsky R-XSR with Matek F405-VTOL

Hello. I’m trying to get my Frsky R-XSR to work with a Matek F405 VTOL and when I set the Serial6_protocol, I noticed that when using Frsky hardware, there are modifications necessary. Does anyone know where/how to find a how to about it?

Thanks

Or… Can someone recommend a different receiver that will work with a Taranis X9+?

If you’re using serial 6 (TX2/RX2), you should be able to go directly to the s-bus pad from the R-XSR.

SERIAL6_PROTOCOL,23

The modifications are only needed if you want to use the FrSky telemetry for Yaapu (worth it!) Here’s a description of how to access that extra port: Uninverted SBUS and Smart Port on Frsky Receivers - Oscar Liang

If you do that, you’ll connect the extra data line to another UART and configure it as per the Matek website. Flight Controller F405-VTOL – Matek Systems

Frsky Smartport Telemetry

non-inverted (hacked) S.Port signal

any spare Uart_TX
SERIALx_BAUD 57
SERIALx_OPTIONS 7
SERIALx_PROTOCOL 4 or 10(for yaapu)

Its nearly worth just using f7 based flight controllers for the selectable inverters on the serial interfaces, yaapu is very good

If you have a newer receiver there is an un-inverted S.Port pad on the receiver that you can solder a wire to. If you then use the second-most-recent firmware (not the most recent, it has telemetry bugs) you can get F.Port working with Yaapu under ArduPilot.

This gives you both RC control and telemetry over a single UART.