RC8 - Chip-8 Emulator

A CHIP-8 implemented in Rust.

CHIP-8 is an interpreted language originally used in the COSMAC VIP, and made to make it easier to develop games and similar graphical applications. Technically, there was never a "hardware" implementation of CHIP-8, but since it was defined as a virtual machine (with registers, addresses, interrupts, etc), CHIP-8 "interpreters" are commonly refered as "emulators".

It is commonly used as the "hello world" for emulator enthusiasts. If you're curious, take a look at the technical reference to learn more.

Features / Roadmap

• All instructions implemented with test cases.
• Proper, "clipped" drawing.
• 100% pass on the CHIP-8 test suite.
• Sound (buzzer) support.
• Option to set background/foreground.
• Option to change the display size.
• Pause/continue.

Note that this aims to emulate the "normal" CHIP-8, and NOT its multiple variants, like S-CHIP8, CHIP-8C, M-CHIP8, etc. If you encounter "odd" behavir, please double-check if you're using a correct ROM file.

Building and running

Before building, make sure you have SDL2 headers available on your system. On most Linux distributions this is included on the sdl2, sdl2-devor similarly-named package. You will also need to install Rust.

Once everything is installed, just run cargo:

$ cargo build --release

# This will download all dependencies and compile a 'rc8' release binary.
# You can get it at target/release folder

To run with the default options, just provide the ROM name:

# Run the binary directly
target/release/rc8 some-rom-file.ch8

# If you want, you can run directly on cargo too
$ cargo run -- some-rom-file.ch8

To exit the emulator, type Esc. See Keyboard mapping for details.

Command-line options

Use --help to show the available command-line options:

rc8 0.1.0
Rafael Ibraim <[email protected]>
A simple Chip8 emulator

USAGE:
    rc8 [OPTIONS] <FILENAME>

ARGS:
    <FILENAME>    ROM file to load

OPTIONS:
        --bg <BG>                      Set the background color
    -f, --fullscreen                   Enable fullscreen
        --fg <FG>                      Set the foreground color
    -h, --help                         Print help information
    -V, --version                      Print version information
    -w, --window-size <WINDOW_SIZE>    Size of the window (WxH)

If no options are specified, you get a 640x320 black and white output:

You can change the colors to a specific hex value by using --fg and/or --bg. If only one one the values is specified, the system will pick the opposite value automatically.

For example, this was ran with --fg #00dead:

And this with --bg #cabeca:

You can also use -w/--window-size to change the window size, or just -f to make it full screen. In both cases, the aspect ratio is preserved and you will see black bars on the screen to account for the diferent ratio.

Keyboard mapping

 (Your keyboard)                     (CHIP-8 Keyboard)
,---,---,---,---,                    ,---,---,---,---,
| 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 |
'---'---'---'---'                    '---'---'---'---'

  ,-------------,
  |   Spacebar  |      >>>>>>>>      Pause/Resume
  '-------------'
          ,-----,
          | Esc |      >>>>>>>>      Quit
          '-----'

License

For details, please see LICENSE.

This project uses extra resources made by different people:

• Computer Speak v0.3 font, by Mcguy215.
• CHIP-8 Test suite rom, by Timendus.
• CHIP-8 Test ROM with audio, from NinjaWeedle.
• Additional roms for testing from this repository.