I am trying to get UART working on my jetson nano. More specifically im seemingly not able to transmit anything over UART to some Sabertooth motor controllers. I have followed this guide: https://www.jetsonhacks.com/2019/10/10/jetson-nano-uart/ with regards to transmitting in python3 and entering the stop and disable commands. I’m using the older jetson nano with only one camera port if that’s any help.
My sabertooth code is here although I forgot to commit the latest code with the serial .write() method and will update it when i get on my laptop. It is copy and pasted the exact same settings from the jetson hacks demo example.
I have tried/tested:
tried communicating directly with the myRIO (jetson can recive myRIO transmissions, myRIO cannot read Jetson transmissions)
tried slower baud rates like 9600
tried a voltage level shifter (per documentation: sabertooth expects 5v signal, however will act on 3.3v; tested on myRIO which also outputs at 3.3V)
grounds are tied together
I suspect some kind of software issue as I’ve had this problem for a long time and tried it when I bought the nano brand new and it didn’t work. Asking on the forum now because I am fully lost as to what could be the issue, even though this seems like a hardware problem. My question then is: is there any way of confirming in software that it should be functional? I do not have access right now to an electronic testing equipment like an oscilloscope to electrically check the signal, but do measure 3.3v with a multi-meter on the tx pin.
I have not connected the Tx pin to anything else other than the myRIO and sabertooth, and tried to get it working when it was brand new which is why I don’t suspect a hardware issue but cannot be certain.