I bought a T-100 class FPV-drone soldered in China with JHEMCU GHF405 AIO FC (https://images.app.goo.gl/mYG1Xfnp62FLTJDj7) and Crossover RX602-A (FlySky, AFHDS-2A) on it. They soldered only red/black/yellow but even though OSD ist fine, I want telemetry (battery and RSSI) on my TX for the alarms.
It is recommended to wire the RX602-A's telemetry cable to a free UART TX (https://www.mxo-rc.com/xr/6-xr602t-aafhd...fpvrx.html) But I inversed my i.Bus-TX (FS-i6X) and use S.Bus (Not only because of my Tarot Ironman 650 with DJI-NAZA M V2 FC but because of consistency I don't want to change when flying FPV). Does this inversion make a difference here, do I have to use UART RX instead? I am inexperienced in Betaflight, do I have to set the port for telemetry to i.Bus or SmartPort in the ports-tab or will something else appear after wiring and reconnection to Betaflght ?
Thanks for a helping advice.
propix357

I have 5+ XR602T-A FlySky receivers.

They have simple instruction card.

You either use the SBUS pin connected to FC RX
or
the FPORT pin connected to FC TX - this is how you get Telemetry.

When you have soldered the FPORT, 5V, GND. In BF Serial you select FPORT. Also make sure to run the settings for
rx_inverted and rx_halfduplex on the instruction card. Nothing else is required for Radio to see Telemetry.

There is an MXCO firmware update utility. It also allows you to change/configure the receiver.
There are "FAST" SBUS/FPORT setting, but they never work for me. I only use the default the receiver came with.

I understand what you pointed out. On my FlySky-i6X I see sensor IntV1 with e.g. 5.11 V or similar, but ExtV1 always showing 0.00 V. But I wanted to get an alarm sound for battery on my TX and not only figures among many others in OSD. - The drone was China-wired with a yellow signal-wire from the RC-solderpad right beside RC-5V to an unlabeled solderpad at the FC's side edge (must be SBUS, because I have SBUS). The vendors Illustration made me think, that I get telemetry only between FPORT and UART TX ?! Oviously, I assumed a false premise. I will not get battery ExtV1 at all ?!

I will dust off an old FlySky quad to show you FS-i6X cs Jumper TLite.