rustboy

A game boy emulator, written in rust!

Inspired by Ferris Makes Emulators

building and running

Right now, the only build requirement is rust

To run, the emulator expects a dmg_rom.bin with sha1 sum of 4ed31ec6b0b175bb109c0eb5fd3d193da823339f, and the included roms/test.gb

DEBUG=true cargo run --release

If you would like to try other roms, try

DEBUG=true cargo run --release -- roms/my_cool_rom.gb

thanks

• to Dissecting the Game Boy for an accessible visual overview
• Past Raiser's opcode chart for a succinct chart of all opcodes
• the gbdev wiki for bootstrap rom and other reference material
• mmuszkow's game boy disassembler for letting me understand and debug all the roms
• ASMschool for dev-oriented writing
• #rust-beginners for being friendly
• 8080, z80, gameboy~z80, and 6502 opcode comparison gameboy~z80 is funky

documentation

I am trying to verbosely write about the creation process. Please see the development log for a narrative, and notes for more of a scratchpad.

Some of the more interesting commits, due to documentation and understanding of the game boy, emulators, or rust:

• reading and printing a header from a rom
• implementing checksum for the game boy rom
• first multiline commit message
• what its like to stare at numbers for a long time
• how to model a virtual processor
• blindly copying ferris
• starting to understand differences between arrays, slices and vectors
• *memory mapping / difficulties implementing a trait in rust
• *the first version of the emulator that runs an emulated instruction!

using

To install dependencies

cargo install

Put some roms in roms/, then test their checksums with

cargo test

It should only show 1 passing test - if you want to see that it is testing your roms, try

cargo test -- --nocapture

To run a game

cargo run -- DMG_ROM.bin roms/Tetris\ \(World\).gb

Note, this requires the game boy boot rom, which I cannot distribute. You can google for it though.