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Comment by loloquwowndueo | Hacker News Reader

So this was all just simulated? Where are the pictures of the build?

Back in the day i built a 4-bit CPU on a breadboard (it was huge actually spanned 3 breadboards). Programming the ROM by hand like cavemen (to be fair it was the cave ages). We didn’t carry cameras in our pockets so sadly we didn’t get a picture.

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My "back in the day" project, which everyone in class (could work in team up to 3) had to do was a wirewrapped breadboarded 8-bit CPU. We had to demonstrate it solving some problem. Extra points for doing something with an I/O channel.

At the end, my team drew straws to see who would get to keep it. Alas, I didn't win.

CMU in 1986.

I did the same (4-bit cpu, 11 instructions) in my Microprocessors class, out of 74-series logic, one GAL20V8 to handle the SLE instruction and an EPROM (not an EEPROM - one with the clear window you exposed to UV light to erase.

That was also where I learned about ground-bounce & dynamic IR-drop effects due to those long looping wires between breadboards.

That was a fun class.

Raise your hand if you still have a UV eraser at the bottom of a cabinet somewhere.

I always used the one in the school lab. Since that’s also the only place where I could program the eeprom :)

We actually made it on breadboards, since it was hardwired the bread-borad is now a sea of wires everywhere, and some things are not working too. I am thinking of getting a custom PCB just for the control unit to make it presentable.

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