What is it with the firmware registration key? 

The firmware included in the download packages may be time limited and may need a registration key to remove this restriction.  This is because I want to prevent for-profit organisazions from taking advantage of the available resources. 

Any private person or non-profit organisation will get the registration key free of charge. If you plan to use the firmware in your company: we will need to talk.

To obtain the registration key, send me a message with the project’s name and the serial number of your device (displayed on the About screen or as part of the response to the *IDN? command).