From 'scratch' meaning 74 series LSI chips here. Similar in spirit perhaps to the mighty Magic-1 (http://magic-1.org/), albeit on breadboard (lots of breadboards) rather than wire-wrap. Kudos to everyone who build their own ALU ;-)
One of the most interesting parts I found was it's not created from a spec, but from scanning and etching an actual chip, useful work for all the chips without complete documentation.
Seems very sensational. Where in my 6 year old Core2Quad machine would I find these fabled chips? Or for that matter, where on a modern motherboard would I find one?
From the various articles in the thread it seems that these are single die computers, think something like bringing the cache on die from back in the day.
Judging from the small number of chips in the photograph, they used the higher integration 74 series logic rather than the lower level flip-flop/NAND type.
Interesting :-) I own several ceramic ones of those. But I'm not planning to use them in the near future, instead my next project will be to create my own ALU using solely with 7400 NAND chips.
The goop on the chips is the funniest part - I've taken apart various bits of equipment (mostly from China) and they often attempt to obscure the part numbers to obfuscate, but even they know to grind/laser them off instead of putting goop on top... and it's still possible to figure out what they are just by their package and pinouts.
The low integration of the design suggests that it's probably at least 5 or more years old; these days, all that functionality would fit in 3-4 tiny BGA ICs.
Looks like decent progress being made on cooking up modern replacements for some of the custom chips, too. The prospect of being able to make fully-populated logic boards from off the shelf parts is exciting!
Nice work. These things, and also PAL and/or GAL chips are in a lot of older computers, and have to be cannibalized from another computer to replace. For the PAL/GAL chips, an automated "fuzzer" type rig to reverse engineer them would be nice to have.
I've heard people have decapped these and even recreated (in some fashion) versions of the masks, or circuit layouts. I'd love to figure out how to start a project making actual chips.
The furthest I've seen publicly is the original Playstation ASICs. http://psxdev.ru/ [Russian Language]
Similar in time to the playstation ASICs (and similar design in sort of a soup of standard cells on a CMOS process), but at a gate count similar to Ken's fantastic work here on the 8086 is the work reversing the Gameboy SoC: https://github.com/furrtek/DMG-CPU-Inside
Chip manufacturers, professional chip reversers, and academic institutions have the tooling to take chips apart at varying levels of granularity all the way down to atom by atom if necessary.
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