No PWM Servo (AUX OUT 1) Movement on Cube Orange


Today I switched to 4.2.0rc1 firmware to use the PLND_XY_DIST_MAX parameter during my precision landings. On my hex, I use AUX OUT 1/SERVO9 to control a servo that tilts my camera via PWM. The servo is powered from a 5v BEC plugged into AUX OUT 6. During missions, it is controlled by Drone kit. Currently, I can move the servo freely by hand, whereas previously I couldn’t move it because of the PWM signal “locking” it in place.

On 4.1.5 I had full control of the servo in mission planner “Servo/Relays” (PWM range 825-1825), but since upgrading I cannot move the servo in mission planner. I read the note on the “common-servo” page in but I still could not remedy the issue. Other posts in the 4.2 section seem to have to do with relays, not servo PWM control.

Attached is my current parameter list.
4.2rc1 noservomove.param (18.2 KB)

Any help would be appreciated.


Hi @FrozenAtlas,

One thing that looks suspicious in the parameter file is that the MOT_PWM_TYPE has been set to “5” (DShot300) but the motors are connected to servo1 to servo6. I think this is a CubeBlack (or similar) which has an IOMCU meaning the DShot only works on the auxiliary outputs (see wiki here).

I’m still investigating why this would stop the PWM outputs on ch9 from working…

… I’ve reproduced the issue and added it to our 4.2 issues list. Thanks very much for finding this!

What is the API on mission planner to switch between video inputs

Thanks for pointing out the MOT_PWM_TYPE issue in my parameters list, I am using a CubeOrange.

Because I am only using motors out 1-6 I might try using motor out 8 to control a servo if possible, the theory being it’s only broken on AUX ports.

If I don’t find any solution I will have to revert to 4.1.5 and code something similar to PLND_XY_DIST_MAX.


Edit: Didn’t work, seems that for SERVOx_Function 0 servos nothing happens when given a PWM command. Rolling back to 4.1.5


Txs again for the report. This is definitely a bug in 4.2 and we’re working on a fix. Hopefully that will be fixed for -rc2 or -rc3.

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