Is there any possibility that MP could output certain data - for example: GPS position, Altitude, Battery volts, current, MODE -
to another device through a USB/serial connection? A simple comma delimited format with a “SYNC” byte at the start (0xFE,0xFE for example) would be fine. The user would be responsible for parsing. A simple bit mask would determine which items were sent. Nothing fancy.
MP has all those parameters decoded, and it would sometimes be nice to “grab” them for various uses by an external device.
you can use mavlink mirroring, (CTRL-F) and select mavlink. You will get everything, but you have to parse mavlink, which is not a big deal.
You can write a small plugin in c# to forward all those values to a serial or network connection. In this case you can define your own format.
You can also write a python script that runs in Mission Planner (check IronPython for info on serial ports) which forwards all values to a serial connection.