I've got two way telemetry working on my Ardustation, talking to the ArduPilot Mega (APM) using the standard BinComm protocol (GCS_PROTOCOL_STANDARD). So far I can edit PID values and check essential mission following data, along with the standard summary of attitude, location and heartbeat data.
This should make life a lot easier, being able to tweak the plane whilst airborne and seeing what it's up to - without being required to sit down with the laptop.
To achieve this, I've modified the code in the ArdustationM branch that Michael Smith created. Michael has written an excellent bit of code here and already had the one way telemetry showing the main status page. I've also updated it to use the APM_BinComm library, keeping it in line with the latest APM code.
The APM code was also modified; I merged the 1.0 Beta with the relevant bits from the BinComm branch and coded up broadcasting of values and setting of PID values.
I hope to add more functionality in the future, but will wait until I have used it in the field before deciding on what features will take priority!
--- Update ---
Here's the code
Most of my additions won't work on the stock APM beta code as it doesn't receive data. Here are my additions to the APM BinComm code
Or download the whole of my directory, less your config file
--- Update 2 ---
I've now used the Ardustation in the field and it's everything I could have wanted. Had my plane flying a mission on repeat, the transmitter on my neck strap and the Ardustation to tune the PID values. No more landing to plug into the laptop. It's also great not guessing what waypoint its headed for and remembering what it's going to do next, just glance at the display!
Here's a picture of my enclosure. Not my neatest drilling, but works nicely :-)