Hacker Takes Original Game Boy Online

Retro gaming enthusiasts can now play the original "Tetris" for Game Boy over the internet thanks to modder stacksmashing. With a custom-made adapter and desktop client, YouTuber stacksmashing made it possible to essentially recreate the "Tetris 99" experience with the original game. 

In his video "Online Multiplayer on the Game Boy," stacksmashing details how he created online multiplayer for "Tetris," and how others can play too. He explains what tools he used to build his adapter and desktop client, how they work on a technical level, and other considerations.

"Tetris" multiplayer originally involved two Game Boy consoles connected by a link cable. So, stacksmashing needed to build an adapter and desktop client to mimic the link cable protocol, which allows a Game Boy to connect to another Game Boy. 

First, he needed to connect the Game Boy to his computer and use it to recognize another Game Boy, as if they were connected with a link cable. To do this, he reverse-engineered the Game Boy's link cable protocol. He created a custom PCB (printed circuit board) adapter to connect to the Game Boy and combined it with a Raspberry Pi Pico to plug into his computer via USB. Then, he used React to code his own desktop client, which players can access as a website. 

This setup also works with later releases of the Game Boy that use a link cable, like the Game Boy Advance, Game Boy Pocket, and Game Boy Advance SP.

So far, "Tetris" is the only game enabled for stacksmashing's online Game Boy multiplayer. He chose "Tetris" as the first game to play over Game Boy online multiplayer and reverse-engineered communication protocols for the hardware. 

In the video, stacksmashing explains that communication protocols differ depending on the game, so he only has "Tetris" for now. However, he encouraged others to use his source code and build off of it for manufacturing their own online multiplayer for other games. He even offered his custom PCBs for sale, though they're only available for pre-order at the moment. Buying the PCB would skip the need to pry open a link cable and cross wires on your own. However, people still need to separately buy a Raspberry Pi for the complete setup. If players don't have any friends invested in the project, they can match with others players in stacksmashing's new Discord server.

Stacksmashing's "Tetris" success follows a feat mining bitcoin on the Game Boy. His YouTube channel also features other hardware adventures with retro consoles and games.