If you have any questions, or just want to chat, join us on Discord

Standing on the shoulders of giants, this is a fun project to create, yet another, GameBoy emulator. Checkout TESTS.md for the ever growing tests GoBC passes.

Supported Features

• CPU
• Sound
• Interrupts
• Joypad
• Serial
• Cartridges
  • Cartridge RAM_ONLY
  • Cartridge MBC1
  • Cartridge MBC2
  • Cartridge MBC3
    • RTC
  • Cartridge MBC5
  • Cartridge HuC1
  • Cartridge HuC3
  • Cartridge MMM01
  • Cartridge Pocket Camera
  • Cartridge Bandai TAMA5
  • Cartridge Hudson HuC-1
  • Cartridge Hudson HuC-3
• Graphics
• Timers
• CGB Mode
• Save States
• Load States
• Debugger
  • VRAM
  • Disassembler
  • IO
  • TileMaps
  • Tile Data
• Shaders

Future Features

List is in no particular order and is subject to change. Take a stab at any of them if you feel like it.

• Sound
• Use real Cartridges (via Arduino)
• Implement all MBCs

Known Issues

• Fix Links Awakening DMG (Menu is broken)
• Pokemon Crystal - Battle Scenes Not animating
• Pokemon Crystal - Character is split upon battle entry

Installing GoBC

You need the following dependencies installed:

• Go
• OpenGL

Building from source

go build -o bin/gobc cmd/gobc/gobc.go

Or Install latest binary

go install github.com/duysqubix/gobc/cmd/gobc@latest

Usage

NAME:
   gobc - A Gameboy emulator written in Go

USAGE:
   gobc ROM_File [options] 

VERSION:
   0.0.1

AUTHOR:
   duys <[email protected]>

COMMANDS:
   help, h  Shows a list of commands or help for one command

GLOBAL OPTIONS:
   --debug              Enable debug mode (default: false)
   --breakpoints value  Define breakpoints
   --force-cgb          Force CGB mode (default: false)
   --force-dmg          Force DMG mode (default: false)
   --no-gui             Run without GUI (default: false)
   --panic-on-stuck     Panic when CPU is stuck (default: false)
   --randomize          Randomize RAM on startup (default: false)
   --help, -h           show help
   --version, -v        print the version


Examples:

gobc roms/cpu_instrs.gb --debug --breakpoints 0x100,0x200,0x300 # Run with debug mode and breakpoints
gobc roms/cpu_instrs.gb --force-cgb # Force CGB mode on DMG rom
gobc roms/cpu_instrs.gb --force-dmg # Force DMG mode on CGB rom
LOG_LEVEL=debug gobc roms/cpu_instrs.gb # Set Log level to debug
LOG_LEVEL=info gobc roms/cpu_instrs.gb # Set Log level to info

Key Bindings

Main Window

Key	Description
F1	Toggle Grid
F2	Toggle Debug Information
F3	Change Pallete (DMG Only)
F4	Save Cartridge SRAM
F5	Save State
F6	Load State
A	Button B
S	Button A
Enter	Start
Shift	Select
Up	D-Pad Up
Down	D-Pad Down
Left	D-Pad Left
Right	D-Pad Right
DEBUG ON - Space Bar	Game Pause
DEBUG ON - N	Step N Cycles
DEBUG ON - M	Increase Cycles Per Frame 10x
DEBUG ON - B	Decrease Cycles Per Frame 10x
DEBUG ON - F	Step Frame

VRAM Window

Key	Description
T	Toggle Tile Addressing Mode
B	Toggle TileMap Addressing Mode
G	Toggle Grid
V	Toggle VRAM bank 0/1

Memory Window

Key	Description
Right	Page Down
Left	Page Up
Up	Scroll Up
Down	Scroll Down
Mouse Wheel Up	Scroll Up
Mouse Wheel Down	Scroll Down

Cart Window

Key	Description
Right	Page Down
Left	Page Up
Up	Scroll Up
Down	Scroll Down
Mouse Wheel Up	Scroll Up
Mouse Wheel Down	Scroll Down

Contributors

Thanks to all the people who have contributed to the project and we welcome anyone to join and help out!

Original Developers

• Duan Uys- duysqubix

Contribute

Any contribution is appreciated. The currently known problems are tracked in the Issues tab. Feel free to take a swing at any one of them.

If you want to implement something which is not on the list, feel free to do so anyway. If you want to merge it into our repo, then just send a pull request and we will have a look at it.

Resources and References

Pan Docs

GBEDG

Instruction Set

PyBoy <-- Huge Inspiration

Test Roms Archive