4 ms·
And had much larger "nodes", given that those tubes are much, much larger and farther apart than the SMT transistors on this 6502 replica. It's not even close.
by anyfoo 3y ago
And had much larger "nodes", given that those tubes are much, much larger and farther apart than the SMT transistors on this 6502 replica. It's not even close.
But I think IBM's SLT from the 1960s might come close: https://en.wikipedia.org/wiki/Solid_Logic_Technology https://en.wikipedia.org/wiki/Solid_Logic_Technology
Those little square "chips" are not actually integrated circuits, but effectively small PCBs with surface mounted discrete components (including transistors).
- NikkiA 3y agoThe early PDPs used discrete CPUs, so they'd probably be the closest examples, the 12-bit PDP-5 is the smallest those CPUs went though, which isn't hideously more complex than a 8-bit CPU.
- anyfoo 3y agoI thought about CPUs with either discrete transistors, or with e.g. 74xx ICs. But the former intuitively seemed too big to me (because I was assuming they use large transistor packages instead of SMT), and the latter too small (because a single 74xx logic chip can pack a lot of transistors). So this “hybrid” of having SMT components in a can by IBM seemed close. Happy to learn more!