I am currently trying to implement a bi-directional communication between Arduino and Edison. While it was easy to send commands from Edison to Arduino, the direction from Arduino to Edison seems to be a big problem. So my robot does exactly what it should if I send "movement commands" to the Arduino so this way seems to work nicely. On the Arduino I echo each command and this echo doesn't reach the Edison.
So I hooked up my logic analyzer and all I get are frame errors.
I changed the Arduino sketch to send "Hello Chris" when turning it on. If I have a look at the Serial port without the Edison all is good and it correctly decodes the "Hello Chris". If however I plug in the UART connection, I only record frame errors.
What could be the problem?