gbemu-rs - A Game Boy emulator written in Rust for fun and learning

gbemu-rs is a toy Game Boy emulator written in Rust with the purpose of learning about writing emulators and Rust at the same time. It's pretty rudimentary but it can run (at least) Tetris and Super Mario Land.

gbemu-rs.webm

Getting started

1. Clone the repo

git clone https://github.com/iaguis/gbemu-rs

2. Build

cargo build --release

3. Run

./target/release/gbemu-rs $GAME_BOY_ROM

Keybindings

Key	Game Boy button
A	B
S	A
G	Start
H	Select
Up/Down/Left/Right	Up/Down/Left/Right

Implemented

• CPU
  • All instructions correct (Passes Blargg cpu_instrs tests)
  • Timings are not accurate
• GPU
  • Background
  • 8x8 sprites
• Keypad
• Timer
• MMU
  • Games with no MBC (e.g. Tetris)
  • Games with MBC1 (e.g. Super Mario Land)
• Serial
• Rudimentary debugger (gbdb)

TODO

• Refactor and clean up the code
• Audio
• GPU
  • Window support
  • 8x16 sprite support
• Savegames
• MBC2+
• Game Boy Color support
• Fix some bugs

References

• https://media.ccc.de/v/33c3-8029-the_ultimate_game_boy_talk
• https://imrannazar.com/GameBoy-Emulation-in-JavaScript:-The-CPU
• https://github.com/mvdnes/rboy/
• https://gbdev.io/pandocs/
• https://gbdev.gg8.se/files/roms/blargg-gb-tests/