The Raspberry Pi RP2040 Runs Doom on a Keycap

Raspberry Pi
(Image credit: Bob, TheKeebProject)

There’s seemingly no end to the number of gadgets in the world that are able to run Doom, and thanks to the Raspberry Pi RP2040 microprocessor, this number keeps growing. Today we’re sharing another fascinating Doom port, this one put together by Bob from TheKeebProject who’s managed to successfully run Doom inside of a custom keycap.

The project is built around a tiny custom PCB that features the RP2040 microprocessor. It’s small enough to fit inside of a keycap and is sealed within clear resin. The port is a customized fork of an existing RP2040 Doom port originally created by Graham Sanderson. A few modifications were made to enable support for both SPI and I2C display modules.

According to Bob, the goal of this project was to emulate Doom with as much of its original functionality as possible. Bob wanted to ensure stereo sound, the ability for network multiplayer, save/load functions and any other feature you’d expect from the original game including the original resolution of 320 x 200px.

Is it practical to play Doom on a keycap? We would argue that's subjective. Is it fascinating and worth creating a keycap that can play Doom? We think so and the end result is certainly worthy of a few bragging rights.

The only way to get the Doom experience he wanted in the form factor of a keycap was to create a PCB from scratch. It’s made just small enough to fit inside the keycap alongside a display module capable of supporting the 320 x 200px resolution. A USB port is included to allow for input as well as power to the Doom key.

Bob was kind enough to make the project open source for anyone interested in checking it out in greater detail. You can find his RP2040 Doom fork source code over at GitHub. There you can also check out the original RP2040 code it was forked from by Graham Sanderson to see how it works, as well.

If you want to see this Raspberry Pi project in action, the best place to see it is over at Instagram where Bob has shared a demo video of the keycap running Doom. You can also follow him for more updates and cool projects.

Ash Hill
Freelance News and Features Writer

Ash Hill is a Freelance News and Features Writer with a wealth of experience in the hobby electronics, 3D printing and PCs. She manages the Pi projects of the month and much of our daily Raspberry Pi reporting while also finding the best coupons and deals on all tech.