Writing an Emulator in JavaScript

Interfacing with multiple platforms to create a web, CLI, and native app

Hey there,

It’s been a while since I’ve sent out a message, but I like to make sure I have a good amount of content or something really cool before I send out a message.

Recently, I took on a big project and I wrote an emulator in JavaScript for a system called Chip-8. Here’s a demo of the project. I finally got around to documenting the whole process, so please check it out here:

Writing an Emulator in JavaScript

Chip-8 is the simplest emulator project you can take on, so it’s the starter project for people who want to learn how to develop emulators. However, it’s useful for more than just that niche interest - if you have any interest in learning low-level programming, how a CPU works, what memory and stack mean, I would highly recommend checking out the project. These concepts also apply to working with JavaScript in general.

But that’s just part one of the project - in the second part, I write interfaces that allow me to use the same CPU as the source of a web app, CLI app, and native app, which makes this emulator unique.

These are some of the topics covered:

  • Memory

  • Stacks

  • Input/Output

  • CPU instructions

  • Working with bits, bytes, and bitwise operators

  • Buffers

  • Interfaces

  • Working with the DOM (Canvas API) and the terminal

I’ve written one other article since I sent out a message, part of the Advanced JavaScript series for DigitalOcean.

Understanding Default Parameters in JavaScript

Have a good weekend!