Need docs on how to run Bridge and MAVLink comms on the same port

[hamishwillee]

It is possible to share a UART port with MAVLink. We need docs explaining how. Context was a discussion in the bridge docs - reproduced below.

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+> Note If the selected UART port is busy, it's possible that the MAVLink application is already being used. If it is the case, you can stop MAVLink from NuttShell by typing:

@hamishwillee Will this happen because MAVLink is being used by "accident" and should not be (e.g. it is a configuration issue and the port should be dedicated to the bridge), or will it happen because the port must be shared?

• If the former, then I'd say that is a bug, and in "real use" this should not happen as part of the normal flow. In this case would this not be a troubleshooting bug while we start moving from MAVLInk to RTPS where needed?
• If it is actually a shared port and this could happen intentionally then turning off MAVLink isn't really a solution - right?

@vilhjalmur89 It can be either of them.

• For first case you probably selected the wrong port for either the bridge or mavlink. So stopping mavlink is good enough for testing, but is not a real solution.
• For second case some documentation is needed for how to run the bridge and mavlink on the same port.