Sbus flags for failsafe

[flyingw (Paul)]

Does copter use the sbus failsafe flag to identify a a failsafe condition?

Please advise.

Thanks,

Paul

[LuisVale (Luís Vale Gonçalves)]

No.

Currently the lack of signal on CH3 is considered to trigger the failsafe

[larsks (Lars Kellogg Stedman)]

@LuisVale

No.

Currently the lack of signal on CH3 is considered to trigger the failsafe

I think that is incorrect.

The underlying PX4 firmware obviously has support for the SBUS failsafe signal:

• archived-PX4Firmware/src/lib/rc/sbus.c at a6205e6ec8767024e1c47128641b60ef841972ce · ArduPilot/archived-PX4Firmware · GitHub

The ArduPilot PX4 HAL explicitly checks for a failsafe reported by the firmware:

• https://github.com/ArduPilot/ardupilot/blob/master/libraries/AP_HAL_PX4/RCInput.cpp#L30

So it looks like the answer is “yes, copter uses the sbus failsafe flag”.

…but I am not an expert on the ardupilot code, so it’s entirely possible I’m misreading things.

[LuisVale (Luís Vale Gonçalves)]

Check radio.cpp for copter

[flyingw (Paul)]

Thanks all for your help with this, I figured out with my system that my receiver turns off the signals output to the Navio2. As a consequence failsafe gets triggered because of the low-throttle rule.

Do you have to tell ArduPilot whether you are using SBUS or PPM? I cannot find any parameter in which you select SBUS or PPM.

Thanks,

Paul