HIL setup with APM firmware on PX4FMU?

I'm trying to setup HIL testing with a PX4FMU and APM firmware.  

If I understand correctly, the HIL setup documented on the pixhawk site is using the default PX4FMU firmware, with a different set of installed apps than those installed by the APM firmware.  

I have qGroundControl talking to the PX4FMU over USB, and I have UART1 connected via FTDI (I can interact with nsh).

However, when I try to start FlightGear HIL with qGroundControl, qgc spews this message over and over:

src/uas/UAS.cc 2905 HIL is onboard not enabled, trying to enable.

Is there a recommended guide to running HIL with APM firmware on PX4FMU? Note that I do not have a PX4IO connected.

BTW I ran into problems getting qGroundControl to launch FlightGear on Mac OSX, so I modified qGroundControl and am sharing my changes on github here:



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  • I had run APM HITL on PX4IO (probably on FMU standalone too, I don't remember :P). 

    First of all, to run APM on px4, do not direct your APM makefile to use the standard px4 firmware, rather, use the diydrone's forked copy of that firmware (this one, although, by the looks of it, it seems they haven't updated it for a while, but this is what that worked for me a couple of months ago! If it doesn't work, try the standard px4 firmware too.).

    Now, as to running the Flightgear simulator. I've not had success running FGFS with qGCS, but it always works fine with Missionplanner. So, what I do is, I use MAVproxy to receive packets from PX4 and send them over through separate network ports to MissionPlanner(that connects to FGFS just the same way you'd do for APM) and qGCS (for anything else you might want to do with it). You could also connect to qGCS by starting MAVlink telemetry on a 2nd UART in APM.rc startup script and then connect to qGCS on it. 

    PX4 Autopilot Software. Contribute to PX4/Firmware development by creating an account on GitHub.
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