Cloning a 6502 Apple-1 in just 930 logic gates

Re:Cloning a 6502 Apple-1 in just 930 logic gates by tyingq on Sunday May 10, 2020 @10:24AM (#23132792)

There were commercial computers that did. The PDP-8, as one example (not 74xx, but similar).

Edit: The Xerox Alto CPU was built with 74181 chips.

Cost, power consumption, space, etc, are all disadvantages. I assume the Gigatron is using modern 74HCxx CMOS chips, which consume less power than the original 74xx TTL chips.

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Re:Cloning a 6502 Apple-1 in just 930 logic gates by dboreham on Sunday May 10, 2020 @10:33AM (#23132881)

Yes HC didn't exist and 4000 CMOS was slow. Plus the pcb, assembly and test cost for 40 DIP packages is significant.

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Re:Cloning a 6502 Apple-1 in just 930 logic gates by ttldude on Sunday May 17, 2020 @02:46AM (#23210118)

Typical discrete logics designs were much larger than the Gigatron. So they're not the same. Using 74LS the single board draws 2.5 W.

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