PX4 throttle on aileron channel problem

I have a PX4 hooked up, calibrated, and sitting on my bench behind me.

I’ve got the ESC signal on the M1 pin of the PDB. I have the I/O in and out plugged into the PX4 and the PDB.

I have a couple servos connected to the FMU out, but they are unresponsive. I don’t have the FMU in/out going from the PX4 to the PDB, so that’s probably why. But for now these aren’t my problem.

The receiver is a futaba SBUS receiver, I’ve got the SBUS plug plugged into the receiver port and the PX4’s SBUS port. In GroundControl, I can see my radio responding properly, the channel sliders move appropriately for each channel on the radio. The transmitter itself also shows those same channels moving, so everything is coordinated between the two systems!

When I push the safety switch on the GPS, the motor beeps a few times and if I do both sticks bottom left on the transmitter, it arms the motor. The problem is that some how, my motor responds to roll inputs (channel 1 on the transmitter.) I can’t figure out why and it’s really frustrating. I have RC_MAP_THROTTLE set to Channel 3, I don’t know where else to look.

Maybe if you could provide some details of the following:

  • Pixhawk make and model
  • PX4 version?
  • Airframe type chosen?
  • Is SBUS from Rx connected to Pixhawk RC IN?
  • Do you have a BEC to power the servo rail?