Hello,
I would like to report a bug I discovered while using CUAV V5+ with SIYI UniGCS.
■ Environment
- Flight Controller: CUAV V5+
- Firmware: ArduRover v4.6.3 / v4.7.0 dev
- GPS: CUAV Neo 3 Pro (DroneCAN, connected to CAN1)
- RC System: SIYI UniRC7
- Connection: UniRC7 Airunit → SBUS + Telem (UART) → V5+
- GCS: SIYI UniGCS (UniRC7) + Mission Planner
■ Symptom
The following message appears repeatedly at approximately 1-second intervals in both Mission Planner and UniGCS message windows:
“Sending unknown message (39)”
MAVLink message ID 39 is MISSION_ITEM, which is deprecated in recent versions of ArduPilot. (Replaced by MISSION_ITEM_INT, ID 73)
■ Conditions that trigger the issue (ALL must be met simultaneously)
- ArduPilot parameter CAN_P1_DRIVER or CAN_P2_DRIVER = 1 (DroneCAN driver enabled)
- UniRC7 Airunit Telem port connected to V5+ Telem port via UART
- UniGCS app running and connected to the flight controller
■ Conditions where the issue does NOT occur (important)
- Using SiyiFPV app instead of UniGCS → does NOT occur
- Using ArduCopter firmware under the same conditions → does NOT occur
- Using a different flight controller with ArduRover under the same conditions → does NOT occur
- CAN_P1_DRIVER = CAN_P2_DRIVER = 0 → does NOT occur
- ArduRover with factory default parameters + UniGCS running → does NOT occur
■ Behavior after trigger
Once triggered, the message continues even after physically disconnecting the Telem cable or closing/restarting the GCS. It only stops after performing a Restart of ArduPilot (via Ctrl+F → Reboot in Mission Planner or Hard reset).
I reported this issue on SIYI as well, but since it only appears on CUAV V5+ and Ardurover firmware, I am reporting it on this forum as well.
Thank you.
