Esc configuring error with 9XR/FrSky and APM 2.6

I have a 9XR radio with a FrSky DJT module. I have the APM 2.6 Mega and when I run the Mission Planner with my tx/rx ready, and go into the initial setup-radio calibration, my sticks are all messed up (technical term). The throttle makes the pitch, throttle and roll move, yawl is good, roll makes the pitch and throttle go opposite directions and pitch works like throttle, except that roll is reversed. I’m not sure what I’ve done wrong. I have the 3 wire servo cables running straight from the receiver to the inputs of the APM with no jumpers. I read something about if the radio is PPM, I would need to jump the ‘s’ pins on inputs 1 and 2 (which I have not done). Any ideas? Thanks.
btw, I’m kind of new to most of this stuff. It’s my first time building my own quad.

Sorry, the ‘ESC’ part of the title is misleading. I’m sure once the stick overlap issues are solves, my ESC’s will calibrate fine. The beep tones with them went on forever and although they did power up with the throttle, they also powered up with the pitch (just like the Radio Calibration screen showed). And the configuration once done, would not save. When I powered it down and back up again, nothing saved.
One problem at a time. :slight_smile:

Hi Dave,

A couple of things pop out.

  1. It sounds like you might have some kind of programmed mixing taking place in your transmitter.
    I am pretty sure you don’t want that.
    You should program your transmitter for straight normal airplane acro mode.
    Even for a copter: throttle - rudder - aileron - elevator operation, no elevons, flaperons or mix or any of that stuff.

  2. You need to have 4 servo signal cables for channels 1 through 4 for Throttle, aileron, rudder and elevator.
    Plus one more (Channel 5) for mode select hooked to a 3 position switch if possible.

  3. On the APM you are not set up to run PPM without specially binding your transmitter for it so the 5 cable setup will work just fine. On the receiver side it is perfectly fine to run all the 3 wire cables with signal, power and ground. But you can also run signals only for four of the channels and power and ground on the fifth one (it normally doesn’t matter which one).

  4. Alternatively you can on some FRSky receivers use PPM-Sum if you want but you have to bind the receiver as specified in the FRSky manual especially for it with the correct jumper in the receiver.
    Then you run a single 3 wire (power signal ground) cable from the channel specified for PPM-Sum in the FRSky receiver to the PPM-Sum input on the APM.

From a practical standpoint, for the time being it is probably easier to run all 5 signals in normal PWM mode.

Best Regards, :slight_smile:


That was spot on Gary. Took me a bit to get the servo cables in the right spots, but after a few tries, I had everything ready. Now, of course, the esc’s calibrated great and all is well. Now I just have to wait for lunch tomorrow to give this copter a try. Thanks again for the amazingly quick response.