On the Ardupilot Wiki it shows hooking a Pi up to telemetry 2. On the UAVmatrix site it shows hooking it up on telemetry 2 or the usb port. I’m currently using the usb port. Pixhawk is powered by a power module plus the servo rail is powered by 5.6 volts so the pixhawk could fail over to servo rail power if the power module fails. The Pi is also powered itself with a 10 amps BEC. I have done extensive bench testing using UAVcast, like probably 6 hours, and have also had the boat on the water for about 4 hours and all is well. Is there any disadvantage to using the usb port over telemetry 2? I’ll throw in a video for fun.https://www.youtube.com/watch?v=HdECap3BVTw
Please excuse the moaning while I’m putting the boat in the water. On my knees and lifting 20 pounds in an awkward position.