python-chip8-emu

CHIP-8 emulation in Python

Introduction

This interpreter aims to be compatible with the original CHIP-8 instruction set for the COSMAC VIP with no extensions, with the exception of the 0nnn instruction to execute a machine language subroutine. In total, 34 opcodes are supported. It was tested on Python 3.8 using pygame 2.0.0.dev10.

Usage

$ python3 main.py -h
usage: main.py [-h] [--scaling-factor n] [--cycles-per-frame n] [--starting-address n] rom

CHIP-8 interpreter

positional arguments:
  rom                   ROM file

optional arguments:
  -h, --help            show this help message and exit
  --scaling-factor n    Screen scaling factor (default: 8)
  --cycles-per-frame n  CPU cycles per frame (at 60 fps) (default: 10)
  --starting-address n  Starting address (default: 512)

The following keyboard mapping is used:

Keyboard:    CHIP-8:

1 2 3 4      1 2 3 C
Q W E R      4 5 6 D
A S D F      7 8 9 E
Z X C V      A 0 B F

Screenshots

$ python3 main.py "roms/games/Pong (alt).ch8"

$ python3 main.py "roms/games/Tetris [Fran Dachille, 1991].ch8"

test_opcode.ch8 results:

Resources

Opcode descriptions for method names are based on Cowgod's technical reference. Since this includes a few errors (for example with the description of opcodes 8xy6, 8xyE, Fx55 and Fx65), Matthew Mikolay's instruction set table and chip-8.github.io were used as the primary sources for the technical implementation.