Hi guys. Here's a little experiment we did yesterday using Doug Weibel's spektrum-to-PPM substitute firmware for the APM's ATmega328P, an upcoming (now available here!) Spektrum Adapter accessory board, and an ArduCopter. Sorry about the lack of video, but I can assure you our resident quad pilot Jeff Taylor flew this here at the shop with good results (considering none of this is fully baked)!
The Spektrum Adapter accessory powers the Spektrum module with an on-board 3.3V regulator, takes care of level translation on the single serial line, and has an input pin to enable/disable the regulator (this is used for putting the satellite in bind mode). The four pins are GND, 5V, data, and regulator enable.
I wrote a (very) crude sketch to put the satellite in different bind modes, you can grab it here: https://gist.github.com/ef01907a5c90dd66f987. I've tested it with DSM2, DSMX, and Orange Rx satellites. I've found that "DSM2 1024/22ms" mode is the one that works with Doug's firmware. The sketch is meant to be used on any Arduino Mega style board, it uses Tx1 to enable the regulator and consequently the satellite at the right moment to then receive the bind mode pulses sent out through Rx1. Once the sat is in bind mode, Rx1 is configured as an input again to receive the serial data after binding.
The ATmega328P needs to be re-programmed with Doug's firmware. You can either Arduino-ify the chip with the right bootloader and load the sketch through an FTDI cable connected to IN1 and IN2, or take the easy way and verify the sketch, grab the .hex file, and load it with an AVR ISP programmer.
Once the sat is bound, I soldered the adapter board on to an APM as seen in the photo, directly on the three IN1 pins. IN1 is the 328's Rx and is the only pin needed to receive the satellite's channel data. The small blue wire in the photo is connecting the 5V and reg enable pins to keep the regulator on at all times. The 328's Tx line could also be set high at all times to do the same thing, maybe the binding modes can be integrated into the 328 firmware as well?
After this, all should be the same as when using the full Rx module with servo extension cables. We found no problems with this setup during the Mission Planner configuration steps.
The Spektrum Adapter boards are now in stock in the store! Feedback for future revisions is welcome, and happy hacking!
Comments
No light on satelite so turn tramsmitter on holding
Bind button after a few seconds
Orange light comes on on satelite
Constant
No ppm blue light on main board
Program spectrum toppm hex
Still no ppm light
Start flight planner and radio not picked up
But orange light on constantly
May be wrong spectrum to ppm hex
Should blue ppm light be on
Only time ppm light on flashing when i put original
Hex on main board
Help stu
The best thing to do is buy a cheap receiver (HobbyKing.com has some for around $6). Plug the satellite into the receiver and bind it as you would any other RC gear. Once bound, unplug it from the receiver and plug it into the Oilpan. There is no need to use different hex files with this method.
Do you have checked to bind it?
druckgott
hi managed to compile hex but it does not seam to put sat in bind mode any ideas regards stu
Do you have checkted that you have selectet the right board?
I used arduino v22 maybe it´s a problem with the new version.
Normaly this should work perfekt.
its the bind file im having probs with i get error when trie to verify the sketch so i need the bind file in hex format
stu
I can not exacty remember you have first upload the binding file to the chip and bind the sattelit and then the file which I have uploaded, but i´m not shure
You have to read the blog exactly and then it works.
start to flash to bind automatically do u have to wait or ?
As u gest im not to technally minded stu
Yes, this should work.
here is also a second one I think one is for the 1280 and the oterh for the 2560:
http://www.dateiupload.com/files/G7VL3vFaG0.zip
what do i do when flashed put two boards back together then ?
Help stu