Hi there Embedddev & welcome.
Can you give a little more information, ie. like a RS-232 data or a GPIO?
I like the Nvidia stuff, I have a rock64 with linux on it…
that carrier board looks nice. I have seen this:
The Jetson-IO tool currently supports pinmux setting for groups of pins related to a function, but not for the individual pins. or
maybe https://forum.seeedstudio.com/t/jetson-nano-with-a203-v2-carrier-board-gpio-not-working/266427/3?u=pj_glasso
HTH
GL 
PJ