RC pass through for landing gear

Hi there,
I have a Tarot landing gear which should either retract or deploy.
If I connect it to the radio receiver it works fine.
However, if I connect it to one of the output channels on the Navio,
and set at APM Planner for this channel a RC pass through nothing happens.
Does someone has a clue whats the problems?
I think, I will check, whether I get a signal from the output at all, if I set it to pass through.

Best, Daniel

Okay, I tested it, I get on all channels:

Switch down: 1:0971 2:1499 3:0900 4:1499 5:1553 6:1498 7:1499
Switch up: 1:1972 2:1498 3:0900 4:1498 5:1553 6:1498 7:1499

The same signals I get if I connect a usual radio, which is working.
Weird.

Could it be not so happy about 400Hz PWM from Navio+ instead of 50Hz from Rx?

I think this would make sense. Otherwise I cannot explain this behavior.
Is it possible to change this? Well I can try to put an Arduino in between an override the signal.
If this is really the reason one should prepare a patch for ArduCopter :smiley:

Daniel, unfortunately you can only control frequency of all channels simultaneously. Which means that if you set RC_SPEED at 50Hz, your motors will also get updates at 50Hz. This is a pwm generator limitation. The only solution that I see would be to put something between output of Navio+ and input of the servo, that will lower the frequency.

As a work around, I use two receivers now.
One for the Navio and one for the FPV/Landing gear.
The Channels on the Navio, are anyway better used for something else.