mika412 / noobboy

A simple GameBoy emulator written in C++

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, SDL2 and SDL2 ttf are required. The SDL2 cmake files are already included, as in some systems cmake can't find the packages. The emulator was tested on Linux and MacOS.

Building

$ cmake .
$ make

Running

usage: ./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 and PPU timings
• Correct scanline timing
• 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.

Game Screenshots

Blargg's CPU Instructions Test	Tetris
The Legend of Zelda - Link's Awakening	Pokemon Blue
Donkey Kong Land	Castlevania

NOTE: Some games may not work due to some missing MBC features.