I'm putting this here since I'm unclear where this question would belong.
I want to build a ground station around a Raspberry Pi that can display basic telemetry.
Initially at least, I want to read only a minimal set of attributes, essentially what comes in the VFR_HUD, ATTITUDE and GLOBAL_POSITION_INT messages.
I understand that the MAVLINK data looks similar to what I find in a .tlog file. I think I understand MAVLINK message structure. I can parse these files enough to understand the basic structure of the protocol. I have a generator to construct packet types from the XML specifications.
What I'm missing is an understanding on the higher-level (session-level) protocol. Is there a message the ground station needs to send to APM to initiate a session? What does it need to tell APM? I'm entirely unclear on where I can find documentation that describes all this. I appreciate your pointers.
Ari.
Replies
So now I'm reading MALINK from APM, and I'm parsing out the telemetry, and the CRCs I calculate match what's coming though the serial (wow the extra CRC nonsense). Thank you for your pointers guys!
Now I want to drive my UAV from the ground station. I send RC_CHANNELS_OVERRIDE, but see no visible effect from that. I wonder if I need to say a special please (like, "I'm going to start sending you rc override commands now") or if I'm expecting some type of ACK or NACK from APM.
Ari.