Minor crash and now my quad gets no input.

Techinator

New member
So I powerlooped on an extremely flat battery (stupid) and couldn't pull out, so I plopped down relatively lightly in the grass. I didn't lose telemetry (lua, voltage, ex.), but the fc is getting no sbus signal. Connections are all good. I tried a different receiver, no luck. I also tried to move the rx to a different uart by moving the smart audio to the tx of the uart the receiver was on. All that did was screw up smart audio, which I thought was the answer, uart 1 was broken, but then why did the sbus still not work. When in the lua for smart audio all the values are 0, rather than the 3 dashes. Is it possible that 2 receivers (r-xsr) and both the rx and tx of a uart on my fc (dys f4) are broken?

Thanks for the help!
 

ElectriSean

Eternal Student
Mentor
The SBUS has to be on an inverted UART on F4 based boards, that's probably why switching to your smart audio UART didn't work.
 

Techinator

New member
Thank you that worked!!! So it looks like uart 1 is broken. Can I use rx3 for sbus and tx3 for smart audio, or does it have to be on a separate uart?
 

ElectriSean

Eternal Student
Mentor
Thank you that worked!!! So it looks like uart 1 is broken. Can I use rx3 for sbus and tx3 for smart audio, or does it have to be on a separate uart?

They have to be separate unfortunately. I'm not finding a lot of info on that board, do you have a manual? It should specify which UARTs are inverted - some boards have 2. How are you connecting your telemetry? Smart Port is also an inverted protocol, but it's fairly easy to do the uninvert hack on them. If you can post a link to the correct manual and a screenshot of your ports tab I'm sure we can get something figured out.
 

Techinator

New member
I figured it out! I have 3 uarts... only rx1 has a hardware inverter. So I put sbus with the uninverted signal on rx3, smart audio on tx2 (which was labeled rx2!!!!!), and s.port with the un-invert hack on tx1. It's all working perfectly now, but I still don't understand why smart audio won't work on uart 1. (not that it really matters--it works)

Thanks for your help!!!:)