Pixhawk and DX18 - Only 12 channels detected

Hi ,

I have a DX18 TX with a 9 Channel AR9020 RX and have been able to bind the channels using the guide here :https://pixhawk.org/peripherals/radio-control/spektrum_dsm

I am able to bind 12 channels whether I set the TX to XPlus mode or not (note, I do not have an XPlus module, I just use the mode to set up the channels on the TX side). My question is two fold :

1) Why is the pixhawk not able to see all 18 channels? If its because I lack the XPlus module, then how am I able to see channels 10,11 and 12 (since my RX is only 9 channels)? 

2) I plan to use channels 13 and 14 as passthroughs and have tried to configure them as such in Mission Planner, but I can only ever see 12 channels irrespective of if I use PX4 firmware or ardupilot firmware. I have also tried to set up the bind process manually or via QGroundControl with no success. I have also tried to access hal.rcin object to see the value stored in the 13th and 14th channel. Both return a constant non-PWM number.

Thanks for your help. 

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Activity