Write up of my homebrew CPU build

Hello! This is the third part of the series about WCPU-1, my homebrew 8-bit computer. Check out Part 1 and Part 2!

Let’s just get this over with:

Don't look it directly in the eye!

So in Part 2 I simulated the whole design in Logisim-Evolution and tweaked it until I was happy. I was emboldened, and felt pretty confident that I wasn’t going to make any Big Mistakes with the real hardware…

Maybe...

This post covers what actually happened when I started building the physical thing. Spoiler: it was humbling. There are backwards LEDs, floating address lines, cursed EEPROMs, and at one point I just learned to read binary by staring at some blinking lights because I’ve been too lazy or distracted to build an output register yet.

This build of WCPU-1 should be seen as a prototype to validate the design and wiring before moving to the “real” PCB design.

I’ve written this in a sort of “don’t make my mistakes, kid” war-story style, so it’s a little crazed at times and probably a little embarrassing, but here we are.

Also it’s very, very long. Sorry.

You already saw the “hero shot” of the build with all the red lights looking like something out of the Upside-Down, but here’s another shot in the light of day:

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