You can try running sudo npi-config.

In that program you will find Advanced Options -> Serial -> serial2 Enable/Disable

By default it is disabled, so this may be causing your error.

Upbumping this topic as I too can't communicate with ttyUSB0 on nanoPi Neo. I am using the same ubuntu image as you guys (The one the pamphlet recommends that comes with the NEO)

Hi Friendly folks, I have a problem that has had me bogged down for 3 full days now and I'm beginning to hallucinate wild friendly creatures. :evil: :mrgreen: :geek: Im using the NanoPi NEO Linux nanoPi 4.11.2 #1 SMP Wed May 31 15:47:40 CST 2017 armv7l armv7l armv7l GNU/Linux to communicate over UAR...