Why did I fail to change flight mode like this?

[EliotBR (Eliot)]

@robotmark

I went to the reading I copy down the code from Pymavlink · GitBook, found that function there is a cycle.Am I stuck in a loop?

@EliotBR

@MokhtarYahia

if ack_msg['command'] != mavutil.mavlink.MAVLINK_MSG_ID_SET_MODE: continue

Looking more into this, the SET_MODE message is deprecated, and shouldn’t be used anymore. The new approach uses the MAV_CMD_DO_SET_MODE command instead (which is what is sent by master.set_mode(mode_id) ), so the acknowledged command check should be for mavutil.mavlink.MAV_CMD_DO_SET_MODE .

I’m unsure whether this is actually what’s causing your issue(s), but without looking further into ArduSub’s codebase my understanding is it’s at least possible.

Would you be able to try changing that check to see if it fixes the issue?

You can also try checking for both, like in this example.

@robotmark

Another question is how do I switch to another flight mode when I’m in depth hold mode?

I’m not sure what you mean by this. Depth hold is a flight mode. If you have a mode change function that allows you to change into it, you should be able to use the same function to change into a different mode

---

By the way, you seem to have print(<number>) calls littered throughout your code, including re-using the same numbers in multiple files. I’d recommend instead using the logging module, which comes with Python.