[Ladyada] and [pt] had an old keyboard from NeXT, but since it used a custom protocol it wasn’t usable with modern hardware. So they built a custom device to convert the NeXT protocol to USB.

The last firmware update included an AT keyboard decoder library for both hardware versions. There’s a ton of old AT keyboards making their way to the landfill. We’ll show you how to recycle ...

If you don't want to toggle between your old keyboard layout and your new one, you can simply remove the old one after adding a new one. It's a fairly simple process. This will remove the keyboard ...