Translations:Manuals:BXFbl:Radio Setup:FRSKY/17/en
S.Port (inv.)
When it comes to sending telemetry data back to the radio it get's more complicated. There is an older system called S.PORT that allows to send telemetry data using a second line. This was firstly introduced for RC drones. One problem here is that the signal is electricaly inverted similar as it is done with Futaba SBUS. But as most controllers do not have signal inverters by default, FRSky did add an inverted S.Port signal to some of their receivers. So that protocol can be read as "normal" UART. If you've got one of those receivers you can use it in combination with MICROBEAST PLUS / ULTRA and NANOBEAST. Please note that you need to add an additional 10k resistor between signal line and ground/minus in order to stabilize the signal!