FailSafe on AUX pins

Its possible to move FailSafe pin on AUX pins ?

If yes, how ?

Thanks in advance,

Have a nice week-end.

Maybe others do, but I’m not sure I understand your question. What do you mean by “FailSafe pin”?

I would like that when I send a pwm signal to an pwm input aux the controller turn into failsafe mode

That behavior is not directly supported by the FailSafes as described in the linked documentation.

However, here is a workaround that might suit you: Configure your Transmitter with a throttle shut-off switch, which drives your throttle PWM signal BELOW 0% throttle. Thus when you flip that TX switch, the TX sends a throttle value below 0%, and trigger’s the Throttle Failsafe as configured in ArduPlane.

(For example: My 0% throttle is around PWM 1100. I set my throttle FailSafe parameter at 975, and have my shut-off switch send ~950 corresponding to less than 0% throttle. This activates my Throttle FailSafe behavior.)

In fact, I’m using an ppm encoder and failsafe doesn’t work, that its why
I’m trying to set failsafe on an aux pin

Maybe someone else can think of a clever workaround? I don’t know one.

The ppm encoder should just pass through the failsafe behavior of your receiver, so if you can, change your receiver settings. You need it to output a low ch3 signal on loss of link, not no signal or hold last signal, then set your throttle failsafe value a little above what your receiver outputs on link loss.

Thanks for help, but I can’t change receiver settings.

My remote is radiolink AT10, receiver r9d

Google suggests this could help. I don’t know radiolink gear.



Thanks for your help, but I use an arduino nano on one of the pwm receiver output I can’t use SBUS, I must use ppm encoder

You could use sbus, and connect the arduino to a pass through channel on the Pixhawk

Could you explain how to do the passthrough ? (Patameters)

Just set the servo output param to match the input channel you want to use.

Have you tried to set the failsafe on your Rx rather than through your Arduino Nano? Here’s a link you can try:

I have tested the procedure post 5

The procedure works with AT10 and ppm encoder (not only with Sbus receiver)


  • Turn on transmitter and go to failsage options
  • Select throttle, next select failsafe
  • One time you have selected failsafe, lower down the thottle, then long press on Ok (push buttom), it will shows you 15%

Your failsage is set to 15% signal before send the failsage signal to FC
When failsage is set on transmitter with S-BUS, even if you lower down throttle you will always get signal and a higher value than transmitter turned off, so you can not set a PWM value with the 10 unit above the throttle lower and 10 unit lower that the value when transmitter is off.
So I only set it when transmitter is turned off

*Connect drone to MissionPlanner
*Go to Failsafe settings
*Play with throttle if everything is fine you will see it moving
*Turn transmitter off and copy the throttle value when it is off to the failsafe value panel and always enabled RTL or continue mission if you want…


My transmitter allow to send RSSI value on CH 6 to 10.

Could you say if its possible to select CH used by failsafe mode… ?