If your TX is using the square 6-pin plug for trainer port, you can use the undocumented BUS-out pin, which will deliver all Channel-Info AND S.BUS-2 Info in consecutive data-packets.

Advantage of this method

  • you get Channel information aswell (all stick and switch positions)
  • you get the "cleaned" values from the TX, if you modified the sensors in the TX (such as pressing RESET, or defining RPM ratio etc.)

Drawbacks

  • you must alsways have your TX and PC connected on the flying field, which keeps the pilot's position limited
  • the S.BUS-2 signals are modified and the TX will still deliver the last values received, when the connection to the UAV is lost (only the Slot-0 RX-Volt will be 0 to indicate this state)

Creating the plug

Take a PWM cable, cut off one end, leaving the Male plug on the other end. The cable can be longer, or you can work with PWM extension cables to widen the distance between the pilot and the computer. 1.5 Meters worked for me.

Remove the middle (red) cable from the PWM cable - it is not used and therefore should be carefully removed.

Next you require the 6-pin plug which will fit on the back of your Futaba TX. Your model-shop should have them.
Futaba trainer-port pin-layout.png

The pin layout is as follows:
  1. Input trainer signal
  2. Input trainer power
  3. Output trainer power
  4. Output SBUS signal
  5. Ground
  6. Output trainer signal

You must use pin 1 and 2 as shown on the picture.
plug-open.jpg

Now plug the PWM cable into the SIU2 adapter and you are all set!

Last edited Apr 26, 2015 at 3:25 PM by uTILLIty, version 7