Radio channels 1-4 are not moving


I think i’ve seen this issue before but I cannot find any documentation about it.

I’m having a usual setup. Matek H743-slim + frsky r9mm receiver.
The receiver is connected to TX6(Serial7) and is operating with Fport.

After installing Arducopter 4.0.7, I’m seeing that fport is working and all of the channels are moving except for Channels 1-4.
When I’m mapping THR, YAW, PITCH and ROLL to a different channel, that channel will not work as well after a reboot.

I saw the same results after swapping the receiver to frsky rx4r with sbus. same, Channels 1-4 are not moving.

Any help would be appreciated, thanks!


any help would be appreciated :slight_smile:

still didnt figure it out. channels 1-4 are always on 1500 pwm. if I assign the, pitch, roll or yaw to a different channel with rcmap, the new channel will be stuck at 1500 pwm after a reboot

I have a Matek H743-Mini and a R9MM on Fport so same configuration. Post your parameter file.

thanks for the reply @dkemxr.

attaching below the params file. changed it to .txt so I can upload it. I can share any other piece of data that may help


current_params.txt (32.1 KB)

That file format is a pain. From Mission Planner’s Full Parameter List use Save To File.

ok just resolved this issue. it was a problem with qgroundcontrol…
the first line in the changelog here is “Fix Parameter Map RC”.

it seemed connected. once I installed the new version, the issue stopped occurring.
Should I begin using mission planner instead? the UI of it made me look away :slight_smile:

Use whichever you like. Mission Planner is better for configuration and tuning of Ardupilot, both make fine Ground Stations. The device you run it on may decide the choice.