Description

This adapter goes between an Apple M0100 mouse and an Apple IIc computer to workaround an hardware incompatibility. Your Macintosh M0100 mouse refuses to cooperate with your Apple IIc? This adapter is the answer!

Background:
The first Macintosh computers, before the ADB bus was introduced, were equipped with a DE-9 connector reserved for a mouse. The Apple IIc, released a few months later, used the same port for an optional mouse. However, the port now also supported joysticks.

Due to the changes that were made to add joystick support, the original M0100 mouse does not work correctly on the Apple IIc. The symptoms are: Buttons working, but movement in some directions not possible and/or jerky. This incompatibility is specific to the Apple IIc. This adapter is not necessary for other Apple II computers.

Not all M0100 mice have this issue. In fact, Apple made a number of changes over the years, but kept the same model number! As a result, some units actually work correctly when connected to an Apple IIc.