[stephenboyd]

We covered it in the first quarter of the CS program at The Evergreen State College. After a few weeks of being introduced to digital logic, each student had to draw (with an application called Logisim) a simulated simple-as-possible Von Neumann machine up from logic gates and wires. Then we had to write short math programs for them directly into the RAM. Fortunately, Logisim lets you save components as something like functions or macros so it wasn't too repetitive. This project demo video by someone who took the same course shows what the result looks like:

https://www.youtube.com/watch?v=Z8qEz4DwFIg

It was challenging, but it was awesome (and finding that video to illustrate my comment is a blast of nostalgia). It wasn't any harder than most other CS or other sciences courses. And after digital logic, the other CS topics aren't really prerequisite or especially helpful in learning how simple processors work. I really appreciated getting straight to the foundations of how computers work and building up from there.

It wasn't like emulating x86 in javascript, but it was CPU internals. Up until I read your comment, I just assumed this was standard CS stuff.