Flying ELRS until a crash “damaged” rx2…..Was going to remap the SBUS pad to rx2, but noticed it already has the same resource value of A03. I’m now wired to TX2 and “RT2|”(SBUS -see image). FC won’t bind to rx in ELRS configurator. Is there some sort of remapping that needs to take place? Do I keep the CRSF protocol? 

# resource
resource BEEPER 1 B02
resource MOTOR 1 B04
resource MOTOR 2 B05
resource MOTOR 3 B06
resource MOTOR 4 B07
resource MOTOR 5 A00
resource MOTOR 6 B10
resource PPM 1 A03
resource LED_STRIP 1 A08
resource SERIAL_TX 1 A09
resource SERIAL_TX 2 A02
resource SERIAL_TX 11 A00
resource SERIAL_RX 1 A10
resource SERIAL_RX 2 A03

AFAIK UARTs have to work in a true pair format if connected.

Tx from Receiver into SBus remapped port without wireing FC board TX to Receiver Rx, you'll lose Tx telemetry but still have OSD???

RT2 is just RX2 going through an inverter. What is the light on the receiver doing? If the light is on solid with the TX turned off, that pad is being held low and putting the receiver into bootloader mode. Your options are to add a pull-up resistor between the RT2 pad and a 3v3 or 5v pad, or move to TX1/RX1. If you go the pull-up resistor route, you'll need to flash your receiver with the RCVR_INVERT_TX option checked in ELRS Configurator.

Rx light blinks when not connected and is solid when connected. Tx acknowledges a connection and disconnection as well. I flashed the rx on a different board, and thought I could simply transfer it over to the current FC. I'm getting no stick movements in the BF rx tab, and the rx won't flash in ELRS configurator ("cannot detect rx target, blindly flashing").

Am I still limited to the 2 options you mentioned, given the flashing light "normal" behavior when the TX is powered on and off?





RT2 is just RX2 going through an inverter. What is the light on the receiver doing? If the light is on solid with the TX turned off, that pad is being held low and putting the receiver into bootloader mode. Your options are to add a pull-up resistor between the RT2 pad and a 3v3 or 5v pad, or move to TX1/RX1. If you go the pull-up resistor route, you'll need to flash your receiver with the RCVR_INVERT_TX option checked in ELRS Configurator.

If the light on the RX blinks slowly when your TX is off then you don't need the resistor. Just flash your receiver with the "RCVR_INVERT_TX" option checked in ELRS Configurator. I don't think passthrough flashing works through an inverter, so flash via WiFi.

But why not move to UART1?

Edit: Can you show an actual photo of the FC and how everything is wired? If the R2 pad is severely damaged, maybe you've severed the trace between RT2 and the MCU.

Yes, light blinks slowly when Tx is off,  don't I need any resource re-mapping in BF? 
I've already tried flashing with the RCVR_INVERT_TX  box checked. I guess I'll try again with wifi.

(15-Jul-2022, 08:56 PM)V-22 Wrote: If the light on the RX blinks slowly when your TX is off then you don't need the resistor. Just flash your receiver with the "RCVR_INVERT_TX" option checked in ELRS Configurator. I don't think passthrough flashing works through an inverter, so flash via WiFi.

But why not move to UART1?

Edit: Can you show an actual photo of the FC and how everything is wired? If the R2 pad is severely damaged, maybe you've severed the trace between RT2 and the MCU.

Phew! it worked. Thanks!   ......As you suggested, I went back and flashed via wifi (very tedious, or I'm just a jackass!). It bound and I'm now getting stick movement in betaflight... To answer your question regarding UART 1, I need it for GPS. According to the manufacturer (geprc), placing the GPS on any other UART would effectively make it unreliable. Didn't want to take that chance since rescue has saved me loads of times already. 
My final question, how can I ensure my telemetry sensors won't be affected by wiring to SBUS? 

As long as you still have T2 on the FC wired to the RX pad on the receiver telemetry should still be working. Have you gone to your Model -> Telemetry page on your radio and verified you're seeing more than 10 sensors?

(16-Jul-2022, 12:07 AM)V-22 Wrote: As long as you still have T2 on the FC wired to the RX pad on the receiver telemetry should still be working. Have you gone to your Model -> Telemetry page on your radio and verified you're seeing more than 10 sensors?

Again, thanks dude! I just checked, and all former sensors are displaying(more than 10). I really appreciate all your assistance. 


Just out of curiousity, what do you fly mostly?

I fly a little bit of everything: smaller quads (whoops to 4"), fixed wing, and I dabble in helis. I spend more time building than flying, however.

(16-Jul-2022, 12:36 AM)V-22 Wrote: I fly a little bit of everything: smaller quads (whoops to 4"), fixed wing, and I dabble in helis. I spend more time building than flying, however.

Same here; 3 to 4inch, and in 2020, I swore I'd never again buy a bnf quad. The hobby is evolving at lightning speed and I wonder if governments around the world will tolerate it as it gets more and more sophisticated.

Anywayz, thanks again bro, and be safe.