Mission Planner Crashes When Connecting To Crossfire Over Bluetooth

Hi everyone,

I’m in the process of setting up my new Matek H743-Wing and am experiencing a crash when connecting to Bluetooth in Mission Planner.

Here is my setup/testing:

  • TBS Crossfire Nano receiver connected to Matek H743-Wing on UART7 (telem1/serial1). Note that this is the only connection from the receiver to the FC (aside from power and ground, of course).
  • Receiver set that the only two channels going to the FC on UART7 are both Mavlink Rx and Tx channels.
  • “RC by Mavlink” turned on on the receiver.
  • When connected to the FC in Mission Planner over USB, I see RC input from the transmitter, so I know the Mavlink connection is working.

Problem: When I attempt to connect to Bluetooth on COM5 Standard Bluetooth over serial (at 57600 baud), I get “Mavlink connecting”, which will almost always just freeze Mission Planner, rendering it unresponsive. Even if I leave it for a while:

Very occasionally, Mission Planner won’t freeze and I will instead get a “Connect Failed” with the following details:

Other Testing:

I believe this issue is specific to Mission Planner. If I instead open up QGroundControl, I can connect over Bluetooth and QGroundControl updates as I move the flight controller around:

Any thoughts or ideas?

Thanks in advance,

try going to MP settings, and disabling

Thanks for the response @Michael_Oborne. I was really excited about such a simple potential fix, but alas, this is already unchecked:


After I posted this, I disabled “RC By Mavlink” on the Crossfire Nano Receiver, and was able to connect in Mission Planner for about half an hour; all parameters were pulled and the built-in HUD had a decent refresh rate. Then, I lost connection and couldn’t get it back.

Now, I’m stuck in the same place again with Mission Planner freezing while attempting to connect over Bluetooth.


Periodically, I can get Mission Planner to start to connect again if I restart my transmitter, FC w/ receiver, and immediately launch Mission Planner. However, it still often hangs and freezes:

Please help! Ardupilot is my favorite firmware and there’s really no alternative to Mission Planner!

Pairing a serial BT device (like the the Crossfire Transmitter) in Windows 10 creates two COM-port’s.
Have you already tried to connect MP with the other COM-port.

Fixed similar issues for me.

Hi @VRquaeler,

I’ve noticed that too. (I actually end up with Crossfire showing up as two separate devices when in Bluetooth discovery mode in Windows; which one ends up being the luck of the draw).

COM5 - Crossfire 0851 ‘AMP-SPP’ seems to be the only one that “works” for me; and it usually doesn’t work very often, all the time, or very long.

Unfortunately, I’m becoming very concerned that Crossfire’s Bluetooth connection will just never work with Ardupilot/Mission Planner and that I’ve wasted $250, but sporadically I get reports of other people saying it works just fine for them that gives me hope. The fact that very occasionally, I can get Crossfire to connect over Bluetooth to Mission Planner and everything (parameters included) load perfectly is driving me insane; I wish I could make it work consistently.

Do you have Crossfire working with Mission Planner consistently?

I appreciate everyone’s help!

I also encountered the same problem, everything works fine with 1.3.70