Because this cable uses a unique 5-pin Lemo-to-USB connection, it requires a specific to help your computer recognize the instrument as a communication port. The Story of the GEV189: "The Missing Link"
If you don't have the CD, look for the "Leica USB Download Cable driver for GEV189" online, often provided by engineering surveyors' forums . gev189 driver
If you provide more context (e.g., “It’s part of a high-voltage system for HPGe detectors” or “It’s from a 1990s nuclear instrument module”), I can help find the actual technical note or internal report that describes that driver. Alternatively, if you need a generic paper on drivers for germanium detector bias supplies , I can provide relevant citations. Because this cable uses a unique 5-pin Lemo-to-USB