** UNDER WORK **
Only attempt this modification if you know what you are doing and understand the risks.
Flashing this firmware is not reversible and will void your warranty. I'm not responsible for anything that happens. Use at your own risk!
The lack of PPM output on Hitec Optima receivers is disappointing. To fill the void I have written firmware that will work with the regular Optima series (Optima Lite not tested) with a combined PPM or SBUS output.
Optima-PPM-SBUS poject is created taking as a base the good work of https://github.com/zero3nna/Optima-PPM, but adding/changing the next features:
- FailSafe feature added. Official Hitech FailSafe Enable and Disable with button is working.
- Digital communication oputput can be selected between PPM or SBUS.
- Compilation migrated to Arduino IDE + MiniCore
There are three variations of the firmware:
- MIXED MODE SERIAL PPM
- Regular PWM is output on the lower channels of the receiver (1 to N-1) and combined PPM on the highest channel (N).
- MIXED MODE SERIAL SBUS
- Regular PWM is output on the lower channels of the receiver (1 to N-1) and SBUS on the highest channel (N).
- MIXED MODE SELECTABLE PPM/SBUS
- Regular PWM is output on the lower channels of the receiver (1 to N-2)
- Selected SBUS or PPM on the highest channel (N).
- Channel N-1 to select between PPM or SBUS, connect the signal pin to ground (with a bind plug) to select PPM, otherwise SBUS is selected.
All builds are available as .hex-file: TODO
If you want to build the firmware yourself, you will need to set up a proper build environment in Adduino:
- TODO
Make sure you flash the correct microcontroller. You want the slave, not the controller for wireless transfer. Optima 6 and 7 have the pads in similar locations.
Next step is to solder the corresponding cables to the Optima reciever pins.
OPTIMA 6 ICSP connections:
OPTIMA 7 ICSP connections:
I powered the reciever directly over the SPC-Pins with a lipo battery.
Thats it! We can now use our reciever in PPM-Mode.