ADB Devices: Don‘t Connect/Disconnect while Computer Is On

I usually run my AppleShare servers without attached keyboards. When a
keyboard is needed, I simply connect it. Recently, I've noticed that if the
keyboard is plugged in after the machine is booted, the keyboard doesn't
work. This problem seems to happen with newer machines and/or the newer
versions of the system software.

The Apple Desktop Bus (ADB) was never intended to allow power-on configuration changes. This is a dangerous practice, as the ADB fuse is a soldered component on the logic board: if the fuse blows from connecting or disconnecting keyboards (or mice, trackballs, etc.) -- the logic board will need to be replaced. The owner's manuals have always made this clear.

Published Date: Feb 18, 2012