Serial port (UART0) spews garbage. How to use it correctly?

I’m trying to connect to the TX2 serial port / terminal / console using minicom. I’ve set baud rate to 115200, 8N1, no flow control, and connected RX / TX and GND. I am able to connect to the TX2, but when I start it up, I just get a bunch of diamonds with question marks and Chinese characters spewing out in my terminal. What am I doing wrong?

Using screen command or picocom gave the same results, and trying with different baud rates also gives same results. I know the Jetson is working, because I’m able to connect over SSH, but the serial console is not working. What am I doing wrong?

It sounds like what you’re doing “should work.” (This is, assuming that you connected RX on your port to TX on the Jetson, and vice versa.)

The next step in debugging would be to hook up an oscilloscope or logic analyzer to look at the waveform that comes out of the port.
Also, what adapter are you using for the minicom port? What computer do you run the minicom on?

[Whoops. deleted.]

Yes, I’ve quadruple confirmed that RX and TX are not incorrectly swapped (I’ve made that mistake enough times to make it the first thing I check :-)

Running minicom on an Ubuntu 16.04 machine, over an FTDI 3.3V USB/TTL adapter cable. I also tried it on a mac, with the same results.

solved. Looks like there’s something wrong with the serial cable I was using. Switching cables fixed the issue.