BlockBoy V3 *Not for sale yet*

What makes BlockBoy unique

What sets the BlockBoy V3 apart is the obsessive attention to detail. The PCB has been redesigned from the ground up to make the BlockBoy as clean and authentic as possible, with as few visible changes to the exterior as possible.

The 2.8-inch IPS display is software-adjusted to perfectly match the shape and format of the LEGO® Game Boy™ screen window, providing a full and crisp image.

The battery is now mounted directly on the PCB instead of inside the cartridge, allowing the LEGO® cartridges to remain in place and become fully functional. A small magnet is placed inside each LEGO® cartridge, and its position can be assigned to a ROM through the menu. By placing magnets at different positions, multiple cartridges can be uniquely identified and linked to different games. Once configured, the magnetic sensor detects the magnet's position inside the cartridge and automatically launches the ROM linked to that position.

An onboard RTC keeps track of real time, allowing day/night cycles and time-based events to work correctly. Volume and brightness are controlled via custom rotary dials positioned in the correct locations to match the original LEGO controls, while the original LEGO power switch turns the BlockBoy on and off. The D-pad and A/B buttons use membrane switches, just like the original Game Boy, while Start and Select use tactile clicky buttons.

The red battery indicator is now a fully functional LED, replacing the printed battery indicator on the original LEGO set. It glows softly while charging and brightly when fully charged. During play, the LED gradually becomes dimmer as the battery drains, just like the original Game Boy.

Showcase Mode has also been expanded. You can create a favorites list, set a play duration for each game, and use an RTC-linked timer. The BlockBoy automatically cycles through your selected games, with a subtle loading screen between titles. The rear USB-C port allows the BlockBoy to be powered while on the stand, with the cable routed neatly out of sight.

The V3 also introduces Game Link: wireless play between two BlockBoys over a range of up to approximately 5 meters, for example Tetris multiplayer or trading in Pokémon games. Support is still being developed and is not yet available for every game.

WiFi allows the BlockBoy to synchronize its time and manage files on the MicroSD card through your browser when connected to your local network. Software updates can also be installed over the air (OTA), keeping the BlockBoy up to date without requiring a wired connection. External Bluetooth Low Energy (BLE) controllers are supported as well.

The Game Boy Advance emulator has been heavily optimized to make the most of the ESP32-S3's available resources. Stable GBA emulation on the ESP32-S3 is extremely challenging, but these optimizations have improved Pokémon games from around 30 FPS to nearly 60 FPS, with only a few occasional hiccups. Some other GBA games may also run well, but compatibility and performance vary greatly between titles. Other games remain experimental and may run poorly or not at all. To make this possible, Bluetooth, WiFi and USB audio are disabled while playing GBA games to free up as much memory as possible.

Technical Specifications

• Processor: ESP32-S3 N16R8
• Display: 2.8-inch IPS display, software-adjusted to match the LEGO Game Boy screen window
• Battery: 500mAh rechargeable battery (Nintendo Joy-Con HAC-006), mounted directly on the PCB, approximately 2 hours of playtime
• Speaker: Mono 15x24mm
• RTC: Onboard real-time clock
• Audio: USB-C audio output
• Controls: Membrane switches for D-pad and A/B buttons, tactile clicky buttons for Start and Select, rotary dials for volume and brightness
• Battery indicator: Functional red LED for charging, full charge and battery level
• Rear USB-C: Power input, ideal for use with Showcase Mode on the stand
• Side USB-C: Charging and data transfer, located at the EXT. CONNECTOR position
• Wireless: WiFi + Bluetooth Low Energy (BLE)
• Game Link: Wireless play between two BlockBoys, up to approximately 5m range
• MicroSD: Accessible via USB Mode or through your browser on your local network
• Software updates: OTA (over-the-air)

USB-C audio compatibility: Audio devices must support 3.3V to 3.7V operation. 5V-only audio devices are not supported. Compatibility may vary between devices.

Supported Systems

• Game Boy (GB)
• Game Boy Color (GBC)
• Game Gear (GG)
• Game & Watch (GW)
• Nintendo Entertainment System (NES)
• Mega Drive (MD)
• Sega Master System (SMS)
• ColecoVision (COL)
• Native Doom support
• Game Boy Advance (GBA): limited support, with Pokémon titles optimized for improved performance

Note: The BlockBoy V3 is primarily designed to provide an authentic Game Boy experience. While additional systems are supported, compatibility and performance may vary between titles. Bluetooth, WiFi and USB audio are unavailable while playing GBA games.

In the Box

• PCB with display
• 3D-printed parts
• 3x button PCB
• 3x flat cables
• USB-A to USB-C cable
• Screwdriver
• Rear USB port adapter (for Showcase Mode)
• 2x magnets for LEGO cartridges
• 1x dark gray 1x2 brick
• 3x light gray 1x1 tile
• 2x black 2x2 tile
• 1x 1x1 battery brick

Software 

The BlockBoy runs on a custom fork of Retro-Go, an open-source firmware originally created by ducalex and licensed under GPLv2.

The BlockBoy source code is available on GitHub.

MicroSD Requirements

The BlockBoy supports MicroSD cards for storing games and other files.

USB Mode can be enabled from the menu to manage the MicroSD card through a USB connection. Alternatively, when the BlockBoy is connected to your local network, you can manage files directly through your browser via blockboy.local.

Note: No MicroSD card or games/ROMs are included with the kit. You will need to provide your own MicroSD card and legally obtained game files.

Installation

To install the BlockBoy kit, some original LEGO bricks are replaced or moved. The kit includes all necessary replacement bricks and custom 3D-printed parts to complete the build and fill any gaps.

For detailed installation instructions, please see the BlockBoy Instruction Manual.