Unlock the full potential of your Game Boy's link port with GBLink! Designed for developers, retro gamers, and hobbyists, this compact device bridges the gap between your PC and your classic handheld console. On one end, a Micro USB port connects seamlessly to your computer, while the other end features a standard Game Boy link connector. The GBLink adapter shows up as a standard UART serial device and translates UART packets to the Gameboy's serial protocol both to and from the Game Boy, enabling direct interaction with your favorite games and custom ROMs from your computer.

Whether you're trading Pokémon in the original Game Boy games, developing custom software to interact with multiplayer titles, or experimenting with homebrew ROMs, this adapter provides endless possibilities. Its plug-and-play design makes it easy to set up, while its versatility makes it an essential tool for anyone passionate about retro gaming or Game Boy development.

Key Features:

• USB UART Serial: Communicate your PC and Game Boy using the common UART protocol and the GBLink translates to/from a connected Game Boy console bi-directionally.
• Compatibility: Supports original Game Boy, Game Boy Color, and Game Boy Advance/SP consoles. Other Game Boy clones like the Analogue Pocket and Mod Retro probably work too.
• Versatile Use Cases: Trade Pokémon, develop multiplayer tools, or interact with homebrew software.

Software

The firmware for the onboard ATTiny412 microcontroller as well as a sample program to communicate with a Game Boy ROM are available in this repo

Firmware

The firmware for the ATTiny412 implements the serial protocol described here, letting your computer behave as the master Gameboy. It will initiate a transfer to the Game Boy when it receives a byte from your computer through UART and forward it to the Gameboy, while simultaneously receiving a byte from the Game Boy and then forwarding it to your computer over UART. The GBLink comes pre-flashed with its firmware, but it can be modified using a UPDI programmer.

Serial Communication

You can write programs to communicate with Game Boy ROMs that use the Link Port by writing to the USB UART device. There is an example program for communicating with Pokemon Gen I games in the GBLink Repo

Bring your retro gaming projects to life and rediscover the magic of your Game Boy with this adapter! Link cable and Micro USB cable not included.