You should watch the video at the bottom, it shows you how to set up the tech in the game. Up to 255 I/O blocks, monitors, and disk drives are addressable on one ribbon cable bus. You can save your programs to floppies, and trade floppies with other players by copying files from a folder on your host computer.
This is a 6502 emulator written in Java and embedded in Minecraft. It's neat, but not as impressive as a 6502 built using the in-game logic gates, which is what the title implies.