Game Bub

Game Bub is the first fully open-source FPGA retro-emulation handheld. Game Bub plays your collection of physical Game Boy and Game Boy Advance cartridges, and supports link cables for multiplayer gaming with other Game Bub devices or original Game Boy and Game Boy Advance systems.

Play It Again

Game Bub modernizes the classic handheld experience with detailed stereo speakers and a vivid backlit IPS screen. You won’t need to hunt down AA batteries, either—Game Bub has 14+ hours of battery life and is rechargeable over USB Type-C. A durable transparent enclosure shows off the electronics inside, 90’s style.

Game Bub is easy to use: no need to fiddle around with setup or configuration to play your games. Just pop in a game cartridge and go!

The emulation cores are custom-built from scratch with accuracy and hardware compatibility in mind. With Game Bub, you’ll benefit from ultra-low input latency and compatibility with a wide array of original accessories.

No Flash Cart Needed

Game Bub can play more than just original cartridges: enjoy the thriving Game Boy homebrew and romhack scene by loading ROMs you own from a microSD card— no separate flash cart needed!

Game Bub has capabilities unmatched by even the fanciest flash carts, at no additional cost. With built in rumble, real-time clock, accelerometer, and gyroscope, most games, no matter how unique, will work the way you expect.

Fully Open and Hackable

Game Bub is fully open source: the hardware, firmware, and gateware are licensed under GPLv3 (software) and CC BY-SA 4.0 (hardware), ensuring that modifications are shared back into the community so that everybody can benefit.

Just like other emulators, Game Bub is built upon decades of hard work and research by the emulation community. With Game Bub, we’re contributing back to the vibrant open-source video game emulation community, through our own original research and open software.

We firmly believe that openness, not secrecy, is essential to video game preservation: all of our research is published via our source code and other documentation. We respect our users, too: Game Bub is not locked down to make you buy more products, or to prevent you from building or modifying your own device.

Game on the Big Screen

Want to play on a larger screen? No problem! With the Game Bub Dock (a separate accessory), you can connect your Game Bub handheld to a TV or monitor.

The Dock also adds Bluetooth controller support: it’s compatible with Xbox, DualShock/DualSense, Switch Pro, 8BitDo, and others! Xbox-compatible wired controllers can be used through one of the USB ports on the rear, and more wired controllers may be supported in future software updates.

We wanted to make Game Bub as useful as possible, so for maximum utility, we also built cartridge backup and restore functionality into Game Bub!

Using the popular open-source FlashGBX software, Game Bub can back up and restore save files from your Game Boy, Game Boy Color, and Game Boy Advance cartridges: never lose a save file again. Game Bub can also back up the cartridge ROM, reflash external (rewritable) cartridges for use with other devices, and even save photos from a Game Boy Camera!

Limitless Expansion Potential

Game Bub is more than just an FPGA Game Boy emulator. It’s fully open source and fully hackable, so you can use it as a portable, self-contained AMD Artix 7 FPGA development platform. Game Bub is not locked down in any way: custom software gets unrestricted access to all on-board hardware.

The Artix XC7A100T FPGA is super powerful, allowing for numerous possibilities. As a point of comparison, the Game Boy Advance FPGA core consumes less than a third of its logic resources!

Game Bub is built with future extensibility in mind, with built-in Wi-Fi and Bluetooth, extra memory, peripherals, and a PMOD expansion slot for custom accessories. Batteries are included, literally and figuratively! Develop your own FPGA game cores, or use it to build other interactive FPGA experiences with its suite of I/O, peripherals, and features.

Features & Specifications

Classic System Compatibility

• Game Boy-compatible cartridge slot for Game Boy, Game Boy Color, and Game Boy Advance games
• Custom FPGA cores designed for high accuracy and physical hardware compatibility
• Built-in ROM loading and backup
• GBA-type multiplayer link port (also compatible with Game Boy Color)
• Rumble motor for games with force feedback
• Accelerometer and gyroscope for compatible games
• Real-time clock

Modern System Specs

• Enclosure: Transparent plastic
• FPGA: Built around the powerful AMD (Xilinx) XC7A100T FPGA, with 101,400 logic cells and 607.5 KiB of block RAM
• MCU: ESP32-S3 microcontroller for auxiliary tasks
• Wireless: 2.4 GHz Wi-Fi and Bluetooth LE
• Memory: 64 MiB of SDRAM and 512 KiB of SRAM connected to the FPGA
• Display: 4.0-inch 720 x 480, 24-bit color IPS LCD
• Audio: Stereo 1 W speakers, TRS headphone jack
• Input: 12 buttons for the FPGA, 4 additional system buttons for the MCU only
• Expansion: PMOD header
• Storage: microSD card slot
• Power: USB Type-C charging, 3000 mAh battery with 14+ hour in-game time
• Optional Dock: Digital video output and wireless controller compatibility, simultaneous charging
• Dimensions: 85 x 174 x 19 mm (3.35 x 6.85 x 0.75 in)
• Weight: 250 g (8.82 oz)

Block Diagram

Comparisons

Support & Documentation

Game Bub is fully open source! All hardware, firmware, and gateware source files are available on the GitHub repository.

The repository contains a detailed architecture document. Other documentation, including a full user guide, will be made available by the time products ship.

Manufacturing Plan

We’re partnering with Elecrow for the mass production run.

Fulfillment & Logistics

After the devices are manufactured by Elecrow, they’ll be packaged up and sent to Crowd Supply’s fulfillment partner, Mouser Electronics, who will handle distribution to backers worldwide. You can learn more about Crowd Supply’s fulfillment service under Ordering, Paying, and Shipping in their guide.

Risks & Challenges

Game Bub has been in active development for more than three years, and the software is stable and essentially feature complete. Testers have used prototype devices for hundreds of hours, and the emulation cores are stable and have high compatibility. However, there will still undoubtedly be compatibility issues and inaccuracies. As these issues are discovered, we’ll be updating the emulation cores and publishing new software updates.

Game Bub is a complicated product, involving a lot of different components, and we don’t have mass manufacturing experience. This is why we’ve chosen to partner with Elecrow, who will be able to use their manufacturing expertise to help with production challenges.

Component shortages could cause delays, but Game Bub is designed with widely available components to help mitigate this. Additionally, tariffs could cause price volatility.