LL530 is an adapter that lets you connect Amiga Keyboard/Mouse and Atari controllers over USB.
This is the public repository for the LL530 project. Various firmware updates are in the Firmware directory, while schematics, and other documenation are in the Docs directory.
The original code for the first version of the keyboard interface can be found in the Reference folder in the Firmware directory. That code wasa retrieved from the forums at Arduino.cc