UART bitrate/speed

baud 115200 means 115200 bits per second only if each baud = 1 bit. If each baud is 5 bits, then having baud 115200 means a bit rate of 115200 * 5 bits per seconds.

source uart - Baud rate vs. Bit rate - Electrical Engineering Stack Exchange
I am trying to find out what bitrate is supported by NX UART

It seems that folks with TX2 got it more like 8Mbit/S, right? So will it be the highest possible bitrate for the NX devkit? Or even 1Mbit/S is problematic?

I have not done so personally, but I know people have:
A. Succeeded at this rate.
B. Not had this be useful unless using two stop bits (because the clock is not in spec).

Does the other end of the UART connection have the ability to use two stop bits? If it does, then I think you will succeed, but if not, then I think you will be frustrated even if you get that rate.

Per Xavier TRM, maximum baud rate is 12.5MHz and identical to TX2. There is a post about running at 12Mbps. Please refer to
Jetson AGX Xavier UARt at Higher Baudrate - #3 by JerryChang

Thank you for following up!
Can we use something similar to iperf to monitor the bandwidth capacity of UART ?

Sounds a good idea, but we don’t have tool, and need to to investigate. Sorry for that.

I suppose there might be some weird way to use netcat with iperf, and then the netcat destination is just localhost, whereby the destination is what talks to the UART (via another pipe). Loopback networking would be a bit of a penalty, but it would be trivial in comparison to UART speeds (the trick being you’d have to force ethernet to send immediately instead of waiting for MTU or delaying and sending on timeout if MTU is not reached).

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