72 Mz and ArducopterNG (1.54)

I've got a JR XP7202 which is a 7 channel 72MHz Tx.

On the 'copter, I've got a JR 790.  They talk using sPCM.


Works great in the CLI, but not in "flight" mode (whatever non-CLI mode is).

I've found a method/function call (APM_RC::GetState() ) which never seems to go non-zero with the FM setup.

So the call

if (APM_RC.GetState() == 1)

is never true.


Is this something I need to "tweak", or am I barking up the wrong tree here?


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  • Making progress here.


    It's not the radio.  Sorry, chaps.  I found a radio diagnostic and ran it, which worked fine.


    By adding various print statements, I see that what happens is that the main loop starts, reads the radio, reads the GPS and loops a few times (14 to 20) before stopping printing.


    So I think that something isn't working right (either because my hardware skills are poor -or- I've misconfigured something in the header file).  Somewhere there's a bit of code that thinks it is waiting for a device to come ready ...


    Time to start turning off things and seeing where I am going awry.

    Got it. 

    if I undefine the Magnetometer, then I'm looping successfully.   Now to go figure out what's what.


  • When in FLY-mode is the PPM Light on on the APM?  I just switched over to spektrum and Turnigy radios from the Jr 8303 8ch FM.  I used the  Jr 790 with my Trex 450 heli.  The 790 doesn't have a crystal right? just a little button?  I had a tough time setting mine up with my Tx radio.  Try another reciever first.    
  • 3D Robotics
    If your Rx puts out standard PWM it should work. Can you post the output of your radio test in the CLI?
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