Originally published at: SmartPort Telemetry Via SoftSerial (BetaFlight)
Smart port telemetry requires an inverted serial signal, but many flight controllers only include hardware inversion on the SBUS connector. So if you want to use SmartPort telemetry on your Frsky receiver it can sometimes be a pain. The easiest way to overcome this is to simply use soft serial which emulates the inverter via software. This guide will show…
I have ordered the omnibus f4v6 and i want to use it with INAV. I Want to know if I can use smart port telemetry and how? I have R9mm receiver Thanks
On inav its abit different as I don’t think it supports softserial at the moment. But the good thing is that you have an r9mm recover which actually outputs an uninverted serial signal… so you just need to connect the smartport from your Rx directly to a spare UART TX pad on the FC 
Oh I didn’t know that. As the schematic on the manual of R9mm says ''inverted S.Port" I was little bit confused. But in fact is uninverted. So I will be able to solder the uninverted s.port of R9mm to the TX1 of omnibus f4v6 and it will works with no softserial needed. Is that right? Thank you so much.
Yes that is correct and it is very confusing. Frsky gear usually outputs inverted serial signal… so when they say inverted s.port it is like saying they inverted the already inverted s.port signal so it’s just a normal serial connection! Next question is why did they call it the r9 mm? What is the mm for?