INAV 8.0.0 Peripherals DJI FPV VTX does not work with Receiver SBUS (DJI RC)

[keefo]

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Hi @mmosca

Please give me chance to provide more info.

I am unable to set UART5 to Serial RX, because the Serial RX and Peripherals are exclusive. When I turn on Serial RX on UART 5, the Peripherals set to Disabled.

I have tried to set other UART1, 2, 3, 4, 6 to Serial RX, and none of them helps with DJI RC.

I also tried just set UART5 to Serial RX and set Peripherals to Disabled. and it still does not work.

Current Behavior

I am using caddx vista VTX and DJI goggle and RC v2. I have 2 drones.

a FPV with Betaflight (caddx vista air unit)
a Fix wing with INav (caddx vista air unit)
The DJI goggle and RC works on my Betaflight FPV. I can connect air unit with Goggle and RC.
In the Betaflight receiver panel I can see all the bars react to my RC control.
This can tell me that my air unit, goggle and RC are not faulty.

For my fix wing, which use Speedybee f405 Wing FC, it flush with INav FIRMWARE 8.0.0 and I am using INav configurator Version 8.0.0 (8.0.0)
This FC has a dedicated Digital VTX plugin-play port (6pins), it has Positive, 2 ground, RX5, TX5, SBUS.
https://www.speedybee.com/speedybee-f405-wing-app-fixed-wing-flight-controller/

After connect them to Inav, I set UART5 Peripherals column to DJI FPV VTX.
Save reboot, at this stage, Goggle works, it can see caddx vista video feed through Goggle.

However, when I go to receiver, it show Receiver Mode as "None" and even if I select SERIAL -> SBUS and click Save and Reboot.

After reboot, the Receiver Mode become "None" again. and my DJI RC unable to control any bar in the Receiver page. The DJI RC light show as green as it does linked to my air unit for sure.

Further more, When I do RC calibration in my Goggle, and it also show that bar react to my gimbal move.

I also checked the continuity of the 6 pin wires, they are all good. So no wiring issue as far as I can tell.

Steps to Reproduce

Expected behavior

Suggested solution(s)

Additional context

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• FC Board name and vendor:
• INAV version string:

[keefo]

Thank you @mmosca for moving my post to discussion board.

[mmosca]

SBUS is not connected to UART 5.
According to the manual, SBUS is connected to UART 2.

DJI FPV VTX is a OSD protocol, not a receiver protocol.

[keefo]

SBUS is not connected to UART 5. According to the manual, SBUS is connected to UART 2.

DJI FPV VTX is a OSD protocol, not a receiver protocol.

After only set UART2 to Serial RX it works.

Thank you @mmosca so much.

I think my test was not working, because I tried to set Serial RX on multiple UARTs at the same time.

[keefo]

Hi @mmosca
I've sent you a sponsor gift to buy you a coffee.
Thank you.