prop chip and R/C PPM

madmike8

I want to use the prop chip as the basis for a programmable R/C transmitter. I want to use it with an ASSAN X8D transmitter trainer port hack module. That way I can just purchase a their R/C receivers for my planes etc. The module requires a PPM signal from a normal R/C Transmitter trainer port. Truthfully, I'm completely clueless on how to encode a PPM signal. Can anyone point me in the right direction.

Thanks

Mike

madmike8

Ok, found this link

www.hooked-on-rc-airplanes.com/servo-tutorial.html#ppm

That explained ppm to where i can understand it. (sorry, I'm ignorant )

Now I just need to get a chip in so I can start playing with the programming.

Jay Kickliter

The timing is slow enough that it could probably be done completely in Spin. I'm pretty sure someone has already done it actually, but I can't remember who.

I was trying to do the same thing, when I realized that it might be possible to forgo traditional RC electronics altogether. I got a couple long-range 900 MHz XBees. I have another project that I'm wrapping up at the moment, so that is on the back-burner right now. But 2 low-latency XBee's and a Prop on both ends might work.

Erik Friesen

Here is some explanation

www.embeddedrelated.com/usenet/embedded/show/57698-1.php

www.aerodesign.de/peter/2000/PCM/PCM_PPM_eng.html

It is not that hard. Just make sure you have it well tested before trying it on any aircraft. JR compatible uses negative pulses and futaba compatible uses positive pulses. An easy way to see what you are doing is to download one of the many sound card oscilliscopes available for free and plug your output( at least with a jr radio training cord) into the high level input. Once you get the scope set you can view what you are doing quite easily.