No PWM Outputs with Custom Breakout Board for Pixhawk Cube


I am creating my own custom carrier board for the Pixhawk cube. I am running into a problem. I flashed Ardupilot firmware to the Cube and installed it on the custom carrier board. I plug everything in and start up the flight controller. I cannot get the ESCs to initialize. I checked the PWM output on the scope and I get no output on the motor outputs

When I plug in to default Pixhawk Cube carrier board (made by ProfiCNC), the ESCs initialize. I check the PWM outputs on a scope and I see 900-1000us PWM signal @ 400 Hz, which is what I would expect.

With exception to the carrier boards, the two systems are equal. On my carrier board, I am not using the power selection PCB. Other than the PWM outputs, I do not see any errors in Mission Planner and the other outputs and status indicators appear to be identical.

Any help would be much appreciated. Thanks!

  • Firmware: ArduCopter 3.5.5
  • Frame Type: Quadcopter


Are you willing to post your schematics?


Yes, but it’s just a breakout board with jumpers and wires. I figured out the problem. The motor outputs are coming from the IO PWM outputs rather than the FMU PWM outputs, which is different from the px4-v4 board that I am accustomed to.

Thanks for your help.