An Intel 8080 assembler and online simulator

While going through Charles Petzold's "Code" book again, I was looking for an easy-to-use online assembler and simulator for the classic Intel 8080 CPU , but couldn't find anything that fit my needs exactly. There are some well-done tools out there, but they seem to be more geared to running game ROMs and earge programs on an emulator; my need was different - I just wanted something to play with, to practice 8080 assembly programming.

So I ended up rolling my own, and the js-8080-sim project was born. The project has three main parts:

• An assembler for the 8080: translating assembly language code into 8080 machine code. I wrote a custom assembler for this.
• A CPU simulator: simulating 8080 machine code. For this purpose I cloned the maly/8080js project into my repositoryand tweaked it a little bit.
• A simple web UI for writing 8080 assembly code, running it and observing the results (as changed values in memory and registers). I wrote a basic UI in JS:

If you want to play with the simulator, a live version is available online at https://eliben.org/js8080

The UI is purely client-side; it makes no requests and just uses your browser as a GUI. It does use the browser's local storage to save the last program you ran.

Issues and PRs on Github welcome!