Wondering if anyone has experienced this before.

I have changed my sysid (MAVLink's way of distinguishing different vehicles) in the APM_Config.h file for a multiple UAV mission (The other a/c need to be able to identify who's sending them messages).

When I go to connect to APM Mission Planner to use HIL Sim, the MAVLink connection freezes getting the sysid and compid parameters. I know the connection is going through, because I can see the changes in attitude of my board on the HUD in the background. However, after a certain amount of time, I get an error screen and "Connect Failed".

I poked around in the sourcecode a bit, but, although I am not very familiar with C#, I was unable to locate where there might be an error reading in a sysid other than 1 (2 in this case).

Any help is much appreciated.




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  • Routing your xbee data through mavproxy to APM or qGCS would remove your 'MAVLink connection fails "Getting Params...(sysid 2 compid 1)"' error. The thing is, for some reason Misiion Planner does not handle API trash in the MAVlink data well(unlike qgcs which has no problem), but MAVproxy cleans the data and just sends the MAVLink packets to APM (or qgcs or both), removing the error. Despite that, APM still wouldn't connect if its receiving MAVLink data from multiple SISID's while its trying to connect, it gets all confused, so if you are using just one xbee at ground station for multiple aircrafts, choose one to be displayed on Mission planner and connect it 1st, then switch the others ON. Meanwhile, MAVproxy would be forwarding all the packets to qgcs port too and he would be silently displaying all the aircrafts!

  • As a follow up to the previous post, I toggled back to sysid=1, and i still have an issue as it reads the parameters. It just gets stuck on different ones. 

    So, perhaps the modifications I have made have somehow interfered with the parameter read-in process... I am not sure how to verify this. I saw in an earlier post that it is possible to connect without loading parameters, and from the sourcecodes, it looks like that is still possible, but how? ctrl-r was mentioned earlier, but that does not seem to work.



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