For nearly 5 years, I've been trying to figure out what this adapter is supposed to connect to. It's still a mystery. Someday, the right person is going to see this post and they'll finally solve this puzzle.
For nearly 5 years, I've been trying to figure out what this adapter is supposed to connect to. It's still a mystery. Someday, the right person is going to see this post and they'll finally solve this puzzle.
When you add @paulrickards' photos as related, it overwhelmingly leans towards a mouse utilizing device, like a digitizer.
I've labeled Paul's 4 quadrant picture. Theory follows:
A - PC side serial port to Sun serial port
B - Mac side mouse port to Sun serial port
C - Used in conjunction with A to make PC side PS/2 port to Sun serial port
D - Sun serial port to Sun serial port
They unified a bunch of host mice ports into the Sun serial port.