Flysky receiver not seen in Betaflight

[drifting willow]

I’m trying to get my betaflight configurator to see the receiver in the desktop app. I’ve been able to bind the receiver, and can detect that it’s outputting a signal (when connecting to the ppm pin with a scope) when I twiddle the sticks on the radio.

I’m working with a generic F4 clone from AliExpress. I’ve tried a few different firmwares, including omnibusv4 and a few other ‘v4’ marked firmwares.

Nowhere in the UI does it show any response from the inputs. I’ve tried reflashing with ppm, SBus as well as iBus as radio type to no avail. I thought maybe my UI was being weird because I was following older tutorials, but even with my receiver configured I see nothing on the inputs in the receiver tab.

I’ve tried setting modes as well as using each available serial RX. I’ve got a wire available on RX1, RX6 as well as the receive pin on top right (inverted iirc). I’ve tried bridging the ppm pad next to radio in, as well as removing the jumper and trying the pad set marked sbus.

I am going to try a different board soon, but will probably get away from cheap clones in favour of a more supported fc.

Any suggestions of things to try or common pitfalls someone who thinks they know what they’re doing may fall into?

[sick robin]

✨AI-Generated response✨

It sounds frustrating to have your receiver signal not recognized! Let's try a few things.

First, double-check the Receiver Mode in the Betaflight Configurator Configuration tab. If you're using iBUS, it should be set to Serial-based receiver, and the Serial Receiver Provider should be IBUS. If you’re using PPM, it should be PPM receiver (https://betaflight.com/docs/wiki/configurator/receiver-tab#receiver).

Next, ensure Serial RX is enabled for the UART you're using in the Ports tab. Often it's UART1 or UART6, but verify for your board (https://betaflight.com/docs/wiki/configurator/ports-tab). Make sure you're connecting the receiver's TX wire to the FC's RX pin, and RX to TX.

Also, for iBUS, SBUS, and Spektrum, the Serial Receiver Provider setting in the Receiver tab must match your receiver type (https://betaflight.com/docs/wiki/configurator/receiver-tab#receiver-configuration).

If you're still stuck after checking these basic settings, it might be helpful to reset your Betaflight configuration to defaults in the Setup tab, in case there's a conflicting setting (https://betaflight.com/docs/wiki/configurator/setup-tab#reset-settings). Occasionally, flashing the firmware again using "Full Chip Erase" in the Firmware Flasher tab can also resolve some issues if the firmware installation was corrupted.

If none of this helps, please head over to the #1052457584772255784 channel; there are many experienced users there who can help troubleshoot further!

[drifting willow]

I’ve tried several clean starts without any change in outcome. I can scope the signal all the way up to the fc but from there I can’t seem to detect anything in software.

It appears that the radio and receiver are working fine, but somewhere in my configuration (likely hardware) I’ve missed something or made a mis step.

[gilded ridge]

The various aliexpress no-name boards re-using targets from other manufacturers are often quite hard to diagnose, mainly from the complete lack of any useful info, but also the fact that they often just... Don't work properly from the factory

What receiver do you have?

[drifting willow]

The ppm/sbus pads mentioned can be seen top right next to the pins I’m referring to as radio input; which I believe is the inverted sbus pin.

[drifting willow]

Flysky fs-i6x with a few fs-IaXb receivers

Osd works and other features seem to be well implemented, but the radio simply won’t show up. I’ll keep trying different targets tonight and see if that does something. I’ve messaged the vendor for information as well.

[drifting willow]

I appreciate the bad news. Thank you for confirming my suspicions.

[gilded ridge]

When I'm home I can take a closer look, though FlySky is unfortunately well beyond my time in the hobby

[drifting willow]

I even went as far as running two receivers and trying both signals simultaneously.

I don’t think it’s a Flysky issue which is why I’m asking here

I can clearly see the PPM signal and PWM if I scope those pins. The issue is in my FC and its ability to digest the signal.

Orange wire is a single pin to try to get the serial signal uninverted to rx1, white is supposed to be connected to rx6 and the earlier photo shows the pin top right that is connected rx1 and supposedly inverted. From my reading soldering the sbus or ppm pad to center changes which uart the rx1 pin connects.

Also, I had solder bridged the ic directly above the boot button for a short while across the top left pair of legs. I fixed it, but could that be the source of my missing receiver signals?

[gilded ridge]

So from what I remember, you'd have the highest success using this port to output IBUS, and connect it to any free RX pad

then you might need to set the receiver to output IBUS in the handset/transmitter settings, but I have no idea how to get to that

[drifting willow]

I've got that set up, and was able to verify the radio is outputting PPM on channel 1 and a digital signal is on the S-Bus/iBus port. I was getting conflicting information about which to select in the UI (S/iBus). The issue is in having the radio signals received. I'll continue reading and share if I find anything.