As follow up from previous posting, some information about how to read out and change values in EEPROM:

I issued following commands:
* M501 to read from the EEPROM
* M92 command from above, verified with the
* M503 command to verify the settings
* M500 to write settings to EEPROM.

Since (Ubuntu linux) minicom does not support serial speeds higher than 115200, I had to use following solution for the communication with Linux:

Download mysetbaud script from the Stackexchange forum, (search for mysetbaud and 250000) and set speed for ttyUSB0 accordingly to 250000

Then I opened two terminal windows:

# Window 1:
Code:
tail -F /dev/ttyUSB0
# Window 2:
Code:
cat > /dev/ttyUSB0
In Window 2 I was able to issue the commands. Interestingly I noticed that before issuing any command from above, I had to start Cura at least once shortly. Otherwise the 3d printer would not accept the commands. It looked like Cura initializes the 3d printer somehow for serial communication. Something I do not understand fully yet.