OberonEmulator

Wirth came up with a simple RISC architecture for his compiler book. There's an emulator[1] for it, written by Peter De Wachter. Michael Schierl adapted Peter's emulator code into Java and JS. You can run it here: http://schierlm.github.io/OberonEmulator/ I sent a bunch of patches to rework the in-browser emulator a couple weeks ago. If you don't know C, I recommend reading through the JS emulator's source. (View source should suffice—it's all unminified vanilla JS; there's no opinionated JS framework involved.) With it running in the browser, the emulator frontend treats the web platform as its widget toolkit. The code to interface with that is in webdriver.js[2] and takes about 1000 lines of code. The CPU and memory operations themselves are implemented in risc.js[3] and only take about 1/3 that. To follow along with instruction

Niklaus Wirth is an amazing engineer/computer scientist, unfortunately he is often unknown by new generations (especially later achievements, like Oberon). I was inspired by his work and never ending quest for simple and effective solutions. If enough people are interested in this project, I am planning to write a blog post series dissecting and explaining the code base (given the small size it should be feasible). Another idea is to port the whole Project Oberon to the JVM like this project https://github.com/schierlm/OberonEmulator, with the difference that the code will run at full speed since there is no emulation involved.