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8-Bit Homebrew Processor


!retrocomputing
So, this isn't exactly retrocomputing and it looks like it's from four years ago, but I just found it and thought that many here may find it interesting.

This guy built a simple 8-bit CPU out of essentially discrete logic circuits (from what I've see so far, nothing more complex than a 4-bit adder chip) and explained the entire process.

youtube.com/playlist?list=PLowโ€ฆ

in reply to Jonathan Lamothe

1. extremely cool
2. The thing is, while rolling back experienced computer performance/degrowthing computing clearly has to happen
I think hand-wired 8 bit computing is an educational rather than practical thing. (Obviously 8 bit AVR MCUs are a practical thing). 32 bit physical lisp machines on fpgas! (Eventually)

retrocomputing reshared this.

in reply to screwlisp

@screwtape Tbh if youโ€™re gonna go FPGA, why not go 36-bit and keep the tag bits? (This is what I keep thinking of doing, anyway.)

reshared this

in reply to curtosis

Unlike me, you should talk to @amszmidt. What do you think about the existing port/emulation of the 1985 LM-3 #MITCADR to #HDL as a starting point for a modern lisp computer (instead of the scheme things that happen sometimes)? (I've tried and failed to get involved because of excuses. ;_;).

I forgot the LM discussion of Actually Using The Extra Bits Available.
@me @retrocomputing

This entry was edited (7 months ago)

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in reply to screwlisp

@screwtape @amszmidt I do vaguely recall it was an interesting question, though not the details. I will admit at least partial interest in the Because I Can factor of historical recreation. ๐Ÿ˜‰

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in reply to screwlisp

Oh yeah, I can't see any practical use outside of educational, but for that purpose, it's a fantastic resource.

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in reply to screwlisp

Silicon foundries use a lot of water and raw materials and contaminate the ground. Full degrowth may involve abandoning semiconductor technologies and making computers out of simpler parts, such as electromagnetic relays. Theyโ€™ll be a lot slower and simpler, but with the right knowledge, one can make them from raw materials without bootstrapping a complex technology chain.

don't like this

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in reply to AllNewTypeFace

@AllNewTypeFace I saw a little bit of research on this kind of thing about a decade ago at a few big universities. Has it gotten anywhere?
in reply to AllNewTypeFace

abandoning semiconductor technologies and making computers out of simpler parts


I remember reading an article a while back about basically computing using cards which block or allow light to flow as a series of logic gates. Another way to think of it is reinventing the punch card.

in reply to Jonathan Lamothe

I bought and built this kit a few years back. Super fun project!
in reply to Jonathan Lamothe

Oh Ben Eater? Heโ€™s got a fairly large following and his other 6502 breadboard computer series is super relevant to this forum
in reply to kalimari

Yeah, I found his videos by jumping down a 6502 rabbit hole.

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in reply to Jonathan Lamothe

Hmm, I can't remember now if I've linked the guy doing his own semiconductor etching in his garage. I definitely have elsewhere, and that's kind of similar.

Just in case: Sam Zeloof

This entry was edited (7 months ago)
in reply to CanadaPlus

He built his first etching setup when in high school,,, after graduating college a few years ago, he ended up starting a company with Jim Keller, the coauthor of x86-64

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