README.md

Emulator 101

This project emulates the Intel 8080 CPU used to run Space Invaders. It also runs Space Invaders in a playable state (I will not be accepting comments about my gaming skills at this time):

Build

This project depends on SDL2 for rendering graphics. To install SDL2 on macOS with Homebrew:

brew install sdl2

Then, to build:

make

Or with another C compiler:

CC=clang make

With debug symbols:

make clean && make debug

Run

For the first argument, the executable takes the folder containing invaders.h, invaders.g, etc. So with the following folder structure,

├── intel8080
└── invaders
    ├── invaders.e
    ├── invaders.f
    ├── invaders.g
    └── invaders.h

the command would be:

./intel8080 invaders

To step through one instruction at a time (useful for debugging or as a reference), use the -s option:

./intel8080 -s invaders

Controls

Currently only single player mode is supported. The mappings are as follows:

Action	Button
Insert coin	C
Start	Enter
Left	←
Right	→
Fire	Space

Controls do not work in step mode.

References

• Computer Archeology
• 8080 opcodes
• 8080 assembly programming manual
• This JavaScript implementation
• superzazu's excellent C implementation