Problems to get DMX to work

[ole]

All current devices share the same base board with one RS485 and one combined RS485/RS242 port. If loop test script does not work then port might be damaged physically. Do you have any plugins like ekey installed? These might use one of RS485 ports by default.

Not that I'm aware of, I have done a factory reset and uploaded a new firmware before starting testing. 
But why does not the port RS485-3 show in the system listing? 
Tried to run the DMX trough port 3, but get an error in the error log