Trackball as mouse

[hellothere123]

I know the trackball works as a mouse, but do you have to install buttons for the select function?

[Blanka]

It depends on the controller used.
I use a Minipac for wiring a 2.25 inch ball, and with the new iPac you have to move 2 pins from the harness to another position as the mouse-button pins are empty by default. But this is a very easy mod. Just use a very small screwdriver to release the pin from the plastic.