I'm working to integrate controls from a homemade cockpit by outputting the desired PPM stream to my Devo10 which runs Deviation. (I'll want the Devo10 to just send the PPM I send to it to the RX, no post processing, etc.)
I'm debugging and am trying to narrow down which aspects of my code (and my custom hardware) are working, and which aren't.
Before I try to send PPM to my Devo10 via the trainer cable, I'd like to output the PPM from the Devo10 and examine it on my oscilloscope to make sure what I'll be sending seems reasonable.
I was a little surprised that the Devo10 uses a 2-pin (Signal + GND) trainer plug with the signal wire apparently switching from input to output based on software configuration. Additionally, I see references to it also being used as a data connection between master and trainer to synchronize settings, etc. Since this is my first interfacing with this style of trainer port, I want to set up testing with test I know will work.
Test 1: Put trainer port in output mode, and monitor the output with oscilloscope
Test 2: Put trainer port in input mode, and monitor servo response.
What I need help with:
1) Precisely what Deviation settings do I need to set to put the trainer port in output mode? (IOW, Generating signal on the trainer port) If I see nothing, I'd like to not worry about if I have Deviation configured properly
2) Precisely what Deviation settings do I need to set to put the trainer port in input mode? (IOW, sending input from the trainer port to the servos.)
3) Is my assumption correct that the trainer port signal is simply PPM? (Obviously, Test 1 can confirm or deny this) If it ISN'T, what protocol is used for the trainer cables?
4) Are their times when the trainer port requires a secondary protocol? (E.G. Do I have to send something to let the Devo10 know to start reading the input?)
5) Anyone know the proper signal level for the trainer port? 3.3V? 5V? (If not, I'll reverse engineer from test 1)
Thanks for any help!
(FWIW, I don't mind reading source code. If the answers are in the code somewhere, you can just point me to the relevant files.)
