Cannot connect to pixhawk via HM-10 bluetooth (HC-06 ok)

I want to swap out the HC-06 for an HM-10 so that I can use my iPhone with QGC for some scenarios whilst still using mission planner on my windows 10 tablet in others.

Sticking with mission planner to begin with, it clearly tries to connect over the relevant comm port but something fails and it says it cannot connect.

Yes, the BT module has been configured for the correct speed (57800), rx/tx are correct, and the tablet can happily pair with it. When using some serial terminal apps I can happily send data between them.

With the HM-10 connected to the pix and then running a terminal app I get some data thru from the pix but it looks gibberish (although not sure what it should look like - I’m assuming nice readable mavlink messages of sorts). I guess I could repeat this but with the HC-06 to establish what I should be seeing.

Any obvious things I may have missed? Is there a way to get more useful info from mission planner on why it failed to complete the connection?



In case anybody else comes across this issue, I kind of resolved it, or at least understood why it will not work.

The HM-10 device is a bluetooth version 4 BLE device and doesn’t implement serial port communication with other devices in the same manner as the HC-06 or HC-05 devices which are Bluetooth version 2.

It won’t work without changes to mission planner.

The only other option might have been to use some software that emulated a com port from the HM-10. This sounded like the sort of thing that somebody might have written to provide legacy support on Arduino projects but I couldn’t find anything.

If I had time, then I could probably have a go at making the changes to mission planner to add support for this device, but that will have to wait for now.