Telemetry via FrSky R-XSR TX to a Cube Orange

I have a EDU450 with a Cube Orange. The Tx is a R-XSR from FrSky but I am unable to get the telemetry through. I have flown it so no issues to get the tx to communicate.

I have connected the Tx to the RCIN with GND - Black, 5V - Red and Green - SBUS (signal pin). Is this correct?


Use the search function on the forum here for “frsky telemetry orange”

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It kind of don’t answer my issue… beyond seen that there is many that see the same issue.

But using a 10K resistor between Signal and GND is a solution that work if you use X8R etc and have a separate S.Bus to Telemetetry2 wire. On the R-XSR you have 5 wires…

I did test it just now, but it do not work. Can anyone say I am on the right track with this wiring?

Beginning to think that I am on the wrong track and all i need is this: SP2UARTConverter - FrSky - Lets you set the limits

Do you have these parameters?


The R-XSR works exactly the same as the X8R except all pins are in one interface instead of two.
I’ve used one in exactly the configuration you are trying.
If using an earlier Pixhawk1 type flight controller THEN you need the UART converter and a diode.

Thanks, good to hear that you’ve done the same. Did you wire it up as I have illustrated?

Will check if I have set the Serial2 as mentioned. I tried to edit some yesterday. But may not have done these…


For what it’s worth, if you are using the ACCESS protocol, I found it easier to use FPort with the R-XSR and simply use a UART for all receiver communication (with a 10k pulldown resistor on the signal line).

ACCST presents some unique problems with FPort due to a bug in the released firmware.

Regardless of SPort vs FPort, if after setting the SERIAL parameters correctly, you still have trouble, try a 4k7 resistor in place of the 10k. Some have reported that the 10k value does not hold the signal low enough for reliable communication.

Thanks Yuri. Will give it a shot. As mentioned, the above wiring didn’t work, so a little at loss at the mom… Also with the proposed Serial2_ settings input.

Could anyone say if the wiring make sense or not… :roll_eyes:

The wiring looks like it should work for SPort telemetry, but I cannot confirm that it works with the R-XSR because I’ve always used the FPort protocol with that particular receiver.

I put the R-XSR on an oscilloscope this morning and confirmed that with my Cube Orange and receiver, the 10k pulldown is adequate. Another user reported otherwise and claimed a 4k7 resistor worked for him - I cannot explain why there was an observed difference with supposedly identical hardware.

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Awsome, thanks for confirming that I am at least on the right track…

Dumbass question alert, but what would you wire differently on the RXSR to get FPORT?

You ignore the RCIN port and run everything over the UART via the receiver’s data pin.

You’ll also need to make sure the receiver is in FPort mode, which is done via the transmitter on the same page as the register/bind menu (using ACCESS).

Just realized, the RXSR (that I got) is ACCST and have S.Port and CPPM… no F.Port. :roll_eyes:

Any suggestion what to do then?

You can flash ACCESS or ACCST Fport firmware to that Rx. Did you review the Frsky Download page for the R-XSR?