I have been thinking about interfacing with my gameboy for a while via the link cable but had no way, other than destroying a cable, to connect it to an arduino or raspberry pi.

Eventually I stumbled upon a blog post where someone had written about the creation of a link cable breakout board. Unfortunately they didn't distribute their CAD file but I figured now would be a good time for me to learn how to create a PCB too.

This is my result, it's very basic but after sending the gerbers to OSHPark I got some boards back which work great.

More about how I made it can be found on my blog: https://palmr.co.uk/posts/26-gameboy-link-cable-breakout/