I am running ubuntu 16.04 desktop and am trying to follow Geduino's guide to connect my udoo with an arduino: http://www.geduino.org/site/archives/284. The arduino serial pins are connected to UART pins 16 and 14 on expansion socket 4. I run the command line: "minicom -D /dev/ttyS5 -b 115200" And I get the following error "minicom: cannot open /dev/ttyS5: Permission denied" I added my user to dialout: "sudo adduser spencer dialout"but still no luck. Has anyone had any experience with this? Thanks!