ProjectDMG is a C# coded emulator of the Nintendo Game Boy wich was originally codenamed Dot Matrix Game (DMG).
This is a personal project with the scope to learn about hardware and the development of emulators.
ProjectDMG dosn't use any external dependency and uses rather simplistyc C# code.
All the CPU opcodes are implemented and it passes Blaarg tests. The emulator have accurate cycle timings to the opcode degree. Including Game Boy related hardware design flaws/bugs as the HALT bug, as some software relies on this specific behaviour.
Note: This is not a M-Cycle or micro-ops accurate emulator. Accuracy and syncronization between the various hardware subsystems as the Pixel Processing Unit (PPU), the Memory Managemet Unit (MMU) or the Timer relies on hardcoded fixed values and varies from 4 to 24 CPU cycles depending on the executed Opcode or hardware interrupts.
Game Boy catalog compatibility should be around +95% as the support have focused on the most popular cartridges types (MBCs 1,2,3 and 5). The full list goes as follows:
| Supported Cartridge Types | Unsupported Cartridge Types |
|---|---|
| 00h ROM ONLY | 08h ROM+RAM |
| 01h MBC1 | 09h ROM+RAM+BATTERY |
| 02h MBC1+RAM | 0Bh MMM01 |
| 03h MBC1+RAM+BATTERY | 0Ch MMM01+RAM |
| 05h MBC2 | 0Dh MMM01+RAM+BATTERY |
| 06h MBC2+BATTERY | 1Ch MBC5+RUMBLE |
| 0Fh MBC3+TIMER+BATTERY | 1Dh MBC5+RUMBLE+RAM |
| 10h MBC3+TIMER+RAM+BATTERY | 1Eh MBC5+RUMBLE+RAM+BATTERY |
| 11h MBC3 | 20h MBC6 |
| 12h MBC3+RAM | 22h MBC7+SENSOR+RUMBLE+RAM+BATTERY |
| 13h MBC3+RAM+BATTERY | FCh POCKET CAMERA |
| 19h MBC5 | FDh BANDAI TAMA5 |
| 1Ah MBC5+RAM | FEh HuC3 |
| 1Bh MBC5+RAM+BATTERY | FFh HuC1+RAM+BATTERY |
Note: SRAM save files are not supported at the moment so your progress on games will be lost on exit.
Execute the emulator and drag and drop a valid Game Boy rom dump to the GUI. The Game Boy will power on and begin execution.
Note: A valid Game Boy BootRom/BIOS file is not needed anymore. The CPU and MMU defaults to post BootRom init values.
Once power on, Input is mapped as:
- D-Pad UP: Up or W
- D-Pad Left: Left or A
- D-Pad Down: Down or S
- D-Pad Right: Right or D
- A: Z or J
- B: X or K
- Start: V or Enter
- Select: C or Space
