Andres_r35

New member
So I’m building a quad, and have gotten a Bn-880 and FrSky R9 mm. I was hoping someone could help connect the R9 mm to my Omnibus F4 Pro. I connected the GPS to UART 3/6 on J10 so that’s gone, and I was planning to connect the Sbus, Ground, and 5V to J7 on the Pinout, but where would I connect the smart port to? I was planning to use Inav with this. Here is a random pinout I found
https://img.banggood.com/file/products/20170619023446omnibus F4 Pro V3.pdf
 

ElectriSean

Eternal Student
Mentor
Your GPS requires one UART, both the Rx and Tx. The Magnetometer needs the SCL/SDA lines. I'm not intimate with the R9 stuff, but I think you may be out of luck for smart port, as it requires an inverted UART, and that FC only has one for SBUS. If your Rx supports FPORT, you can do telemetry and SBUS on one wire, but you may need to upgrade the firmware on the Rx.
 

Andres_r35

New member
Your GPS requires one UART, both the Rx and Tx. The Magnetometer needs the SCL/SDA lines. I'm not intimate with the R9 stuff, but I think you may be out of luck for smart port, as it requires an inverted UART, and that FC only has one for SBUS. If your Rx supports FPORT, you can do telemetry and SBUS on one wire, but you may need to upgrade the firmware on the Rx.
The R9mm receiver I am getting has an inverted S.port, but would that mean I would be able to use it on Rx1 on UART 1? Looking at this manual (https://www.frsky-rc.com/wp-content/uploads/Downloads/Manual/R9 MM/R9 MM-manual.pdf ) it does say it supports F.port.
 

ElectriSean

Eternal Student
Mentor
The R9mm receiver I am getting has an inverted S.port, but would that mean I would be able to use it on Rx1 on UART 1? Looking at this manual (https://www.frsky-rc.com/wp-content/uploads/Downloads/Manual/R9 MM/R9 MM-manual.pdf ) it does say it supports F.port.

Telemetry needs a Tx pad on the FC, and it can't be the same UART as your SBUS uses. Both need to be inverted. Major design flaw by FrSky IMO, as is the use of inversion at all. f.port does it all over 1 wire, that is what I'd recommend. You will need to update the firmware on the Rx, though it's pretty easy.