ZBA (working title)

A Game Boy Advance Emulator written in Zig ⚡!

Scope

I'm hardly the first to write a Game Boy Advance Emulator nor will I be the last. This project isn't going to compete with the GOATs like mGBA or NanoBoyAdvance. There aren't any interesting ideas either like in DSHBA.

This is a simple (read: incomplete) for-fun long-term project. I hope to get "mostly there", which to me means that I'm not missing any major hardware features and the set of possible improvements would be in memory timing or in UI/UX. With respect to that goal, here's what's outstanding:

TODO

• Affine Sprites
• Windowing (see this branch)
• Audio Resampler (Having issues with SDL2's)
• Immediate Mode GUI
• Refactoring for easy-ish perf boosts

Usage

As it currently exists, ZBA is run from the terminal. In your console of choice, type ./zba --help to see what you can do.

I typically find myself typing ./zba -b ./bin/bios.bin ./bin/test/suite.gba to see how badly my "cool new feature" broke everything else.

Need a BIOS? Why not try using the open-source Cult-Of-GBA BIOS written by fleroviux and DenSinH?

Finally it's worth noting that ZBA uses a TOML config file it'll store in your OS's data directory. See example.toml to learn about the defaults and what exactly you can mess around with.

Tests

• jsmolka's GBA Test Collection
  • arm.gba and thumb.gba
  • flash64.gba, flash128.gba, none.gba, and sram.gba
  • hello.gba, shades.gba, and stripes.gba
  • memory.gba
  • bios.gba
  • nes.gba
• DenSinH's GBA ROMs
  • eeprom-test and flash-test
  • midikey2freq
  • swi-tests-random
• destoer's GBA Tests
  • cond_invalid.gba
  • dma_priority.gba
  • hello_world.gba
  • if_ack.gba
  • line_timing.gba
  • lyc_midline.gba
  • window_midframe.gba
• ladystarbreeze's GBA Test Collection
  • retAddr.gba
  • helloWorld.gba
  • helloAudio.gba
• armwrestler-gba-fixed.gba
• FuzzARM

Resources

• GBATEK
• TONC
• ARM Architecture Reference Manual
• ARM7TDMI Data Sheet

Compiling

Most recently built on Zig v0.10.0

Dependencies

• SDL.zig
  • SDL2
• zig-clap
• known-folders
• zig-toml
• zig-datetime
• bitfields.zig

bitfields.zig from FlorenceOS is included under lib/util/bitfield.zig.

Use git submodule update --init from the project root to pull the git submodules SDL.zig, zig-clap, known-folders, zig-toml and zig-datetime

Be sure to provide SDL2 using:

• Linux: Your distro's package manager
• MacOS: ¯\_(ツ)_/¯
• Windows: vcpkg (install sdl2:x64-windows)

SDL.zig will provide a helpful compile error if the zig compiler is unable to find SDL2.

Once you've got all the dependencies, execute zig build -Drelease-fast. The executable is located at zig-out/bin/.

Controls

Key	Button
X	A
Z	B
A	L
S	R
Return	Start
RShift	Select
Arrow Keys	D-Pad