Invalid channel option (185)

ArduCopter Copter 4.6
1

Hello,

I am using a copter with ArduPilot and a Caddx GM3 gimbal.

I configured the gimbal according to the ArduPilot documentation CADDX Gimbals — Copter documentation

Most functions are working correctly, including yaw lock mode. However, I cannot configure pitch/roll lock using channel option 185.

When I assign RC7 option 163 (YAW Lock) it works, but when I change RC7 option to 185 (“Mount RP Lock”), ArduPilot shows the error:

“Invalid channel option (185)”

Screenshot 2026-05-14 141811
Screenshot 2026-05-14 141811726×463 136 KB

Details:

  • Flight controller MatekH743-slim, firmware: ArduPilot Copter v4.6.3

  • Gimbal: Caddx GM3 firmware v4.8

  • Yaw lock works correctly

  • Pitch/roll lock option 185 is rejected as invalid

Gimbal configuration:

Screenshot 2026-05-14 141834
Screenshot 2026-05-14 1418341919×1018 434 KB

Grateful for any thoughts on this!

2

The Mount RP Lock was added for the 4.7 release, it is not in 4.6.

1 Like
3

Is it still invalid after updating to 4.7 beta 4 firmware?

1 Like
4

I have updated to 4.7 beta 4 firmware and it works!

Thank you so much for your help!