See https://github.com/paparazzi/paparazzi/blob/master/conf/modules/rssi.xml#L14
I need a module that can:

1. send an extra telemetry stream
2. receive and parse datalink messages

It is used for:

1. HITL
2. data logging with off-board datalogger
3. communication with payload computer

This was just a simple solution leveraging existing constructs. If you have a better idea how to do it please let me know.