Monday, May 11, 2015

FrSky SBus to CPPM Converter install on X8R to APM 2.5

Since I need some channels for my gimbal, I finally installed my FrSky SBus to CPPM Converter.

This is how you connect it. It goes from X8R's SBus port to APM's first channel (marked A on this FC). Watch orientation of yellow signal wire and you should be fine. You also install a standard jumper on SIGNAL PINS 2 & 3 of the Flight-Controller. The X8R now uses this single cable to communicate to FC for RC-Channels 1-8.

It also powers the Flight-Controller (this is how the FC gets power now). The only other X8R-RX cable pictured here (black-red-white) is BEC+5v input power from PowerBoard.

Radio Re-Binding:

Since my Nova (Model #1) was previously Bound in Mode-1(D8), I needed to re-Bind X8R to Taranis in Mode-4(D16). The 8 physical ports on the X8R will now become RC-Channels 9-16.

Follow X8R binding procedures in manual sheet. Basically, you need 2 jumpers installed and be carefully pressing F/S button (behind tiny sticker-cover) BEFORE you connect battery to X8R. After it powers-up, you can release F/S button. X8R should now be in Binding Mode.

At the Taranis TX radio, you access your aircraft's Model Setup (mine is Model #1 called Nova).
- Internal RF
- Mode: D16
- Channel Range: CH1-16
- Receiver No: 01

Then, you select BIND menu option on Taranis. The Taranis will chirp. The LEDs on X8R might change. It should now be Bound. Exit Taranis menu. Power down X8R and remove jumpers. Power-up everything again and it should be working like before.

Model #2 will use Receiver No: 2, and so on.

The green LED on X8R should be on (and maybe flickering). If basic FrSky Telemetry is working, that's a good sign. The props were off so I tested Arming and it worked fine. Taranis programming it still there.

While I haven't flown it, I re-connected to MissionPlanner and there doesn't seem to be any missing programming or re-calibration needed. The Binding seems to be completely separate from all that. The one exception is FailSafe Mode. Either using OpenTX Companion (or conventional way at RX itself) you need to set FS Mode from "Hold" back to desired "No Pulses". Then, re-test Fail-Safe with FC.

In retrospect, I should have done this in the beginning or sooner. Not only does it simplify FC-RX wiring, the suggested Binding Mode-4(D16), enables a whole set of new channels.


  1. Hi, are you able to have a Telemetry on Taranis ?

    1. Yes. It is very cool. Just use X8R or I think also X6R.

    2. can you help me to have the telemetry? i not use the SBus, is mandatory ? it's necessary other component ? can you show me the connections?

      Many Thanks

    3. As long as RX and TX are bound-together, you get FrSky Telemetry.

      To get APM Flight Controller Telemetry, you need 3DR-Radios.

  2. mmm sorry but i do not understand, you have Taranis or 3DR-Radios?

    1. I have both. And no, SBus Converter is not required. It just simplifies wiring and ends up allowing more channels.


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