CHIP-8 (and Emulators) In Plain English
Let’s say you want to play an old game from the MS-DOS era. You have the DUKE3D.EXE file, you launch it and … nothing happens. But why?
Old systems had a different architecture from your PC. Loosely speaking, your PC doesn’t recognize the program and refuses to execute it. You have to find an adapter that can translate the program to something your PC can understand. And there you have it, emulators!
We will be writing a CHIP-8 emulator for the modern computers. It will take a binary file (aka ROM, Read Only Memory) that a CHIP-8 Virtual Machine (VM) could read and execute it as if your PC was a CHIP-8 machine.
Let’s take a look at the CHIP-8 itself. What exactly is it? A quick glance at the Wiki page tells us that it’s an interpreted programming language. Think of it as a super early version of Java. You could write a game for the CHIP-8 and run it everywhere. Everywhere the CHIP-8 Virtual Machine was implemented for, that is. We are going to re-implement the VM and run some CHIP-8 games as if it were 1970-s again.
A ROM is basically a binary program code with all the data we need to execute it. Your NES cartridge is a ROM. Your BIOS is a ROM. You cannot modify it, hence the name. ROM contains both the code and embedded data like icons, sprites and audio tracks.
