Because he's a Good Boy
GoodBoy is a (yet another) gameboy emulator. The goal of this project is to learn more about emulation and to (hopefully) learn how to write clean & modern C++ code.
Currently the CPU core passes all of blargg's CPU instruction tests. It can play Tetris, Dr. Mario, Kirby's Dream Land, Kirby's Pinball Land, Pokemon Red, Super Mario Land, Pokemon Gold, The Legend of Zelda - Link's Awakening, Donkey Kong & Warioland II. But those are the only games I've tried so it can likely play other games. Currently MBC1, MBC2, MBC3 & MBC5 ROMS seem to work. There is a pretty cool debugger mode; more details below.
The keyboard controller mappings are hardcoded for now: UP -> Up Arrow Key DOWN -> Down Arrow Key LEFT -> Left Arrow Key RIGHT -> Right Arrow Key A -> x Key B -> z key START -> Return Key SELECT -> Right Shift Key
cmake and sfml are required to build this project. To build, run the following commands:
mkdir build
cmake ..
make
To run a ROM:
./goodboy <rom file>
GoodBoy has a debugger mode and tracing mode. To enable CPU instruction tracing you can use the -t option:
./goodboy -t <rom file>
To run the debugger mode you can use the -d option:
./goodboy -d <rom file>
For help on more options, please use the -h option.
The GoodBoy debugger is an ncurses terminal app and supports the following features:
- Halting and resuming execution
- Single stepping through instructions
- Dumping register state
- Modifying and viewing single registers (8-bit and 16-bit registers are both supported)
- Modifying and viewing a single memory location
- Scrolling support to view complete trace in the terminal
- Breakpoints
- Watchpoints
- Saving trace to file
- Dumping OAM memory and viewing sprite tiles (from inside the terminal)
- Dumping background and window maps and viewing tiles (also from inside the terminal)
For command usage, type h in the debugger.