Having just been given a Depraz mouse, I thought it would be fun to get it working on my modern computer. Since the DE9 connector is male rather than female as you usually see with serial mice, and given its age, I speculate that it might have a custom protocol; in any rate, plugging it into a USB-serial converter and and firing up picocom has given me nothing.

Does anyone have a copy of a manual for it, or more information on how to interface with it? If I knew how it was wired and what the protocol looked like, I expect I could make an adapter pretty trivially using a microcontroller.