NoobBoy - GameBoy Emulator

NoobBoy is a simple gameboy emulator that I'm writing to learn more about the world of emulation. This emulator has nothing special and has no extra features compared to other DMG emulators.

Usage

To build the project, cmake, SDL3 and SDL3 ttf are required. The emulator was tested on Linux and MacOS.

Building

To build the desktop version, run the following command in your terminal:

$ make desktop

Running

usage: ./build/desktop/NoobBoy --rom <rom_file> [--bootrom <bootrom_file>] [--load-save <save_file>] [--debug] [--sound] [--no-bootrom]

arguments:
  --rom                     Standard GameBoy rom
  --bootrom                 Load a custom DMG bootrom
  --debug                   Enable the debugger
  --load-save               Save file to load
  --sound                   Enable experimental sound
  --no-bootrom              Start without bootrom

Input

Gameplay

Debug

Action	Key
UP	`↑`
DOWN	`↓`
LEFT	`←`
RIGHT	`→`
B	`x`
A	`z`
START	`Space`
SELECT	`Enter`

Action	Key
Save game	`s`
Toggle color palette	`c`
Pause/Resume	`p`
CPU step	`n`
Toggle sound	`m`
Exit	`Escape`

Features

Sound (WIP)
Correct instructions
Sprites with correct row limitations
Correct sprite, window and background pixel priority
VRAM rendering with X/Y scroll overlay
Memory Bank Controller (MBC)
Debug mode
Save states (dump of external RAM banks)
Custom bootrom (Based on ISSOtm/gb-bootroms work)

Currently, the halt bug is missing because of some incorrect interrupt timings.

Test Suite

Run the test suite with:

$ make test                                 # run all tests
$ make test SUITE=blargg                    # run one test suite
$ make test SUITE=mooneye/acceptance/timer  # runs one test suite
$ python3 tests/run_tests.py                # run all tests
$ python3 tests/run_tests.py --help         # show all options

Results are written to tests/TESTS.md after each run.