The mega processor is one of my all-time favorite computers, along with the Magic-1 <a href="https://homebrewcpu.com/" rel="nofollow">https://homebrewcpu.com/</a><p>The megaprocessor is just absolutely wonderful in how it bridges from 'here is a transistor, it lights an LED' to 'here is a computer, it plays tetris'. I always struggled to unwind the layers of abstraction in a modern computer from atoms in the CPU to running python, but being able to just look at a bunch of literal transistors (with LEDs on each gate!) wired up playing tetris shows how a computer really works in such a profound and awe inspiring fashion.<p>Magic-1 is sort of the next level higher complexity, where it is made out of very simple TTL (most complicated chip function is the ALU--a circuit I had to build as an EE undergrad out of or- and and- gates) and it hosts a webpage. It currently seems to be down, but you can see it on the wayback machine
<a href="https://web.archive.org/web/20210815180101/http://www.magic-1.org/" rel="nofollow">https://web.archive.org/web/20210815180101/http://www.magic-...</a><p>I will never forget when I came across that site and realized that I was interacting with a wirewrapped pile of ram and nor gates over the internet. There was even a time when you could telnet in and play some retro text-based adventure games, To this day, the only time I have played Adventure was on Magic-1.