Hacker News new | ask | show | jobs
by klelatti 1581 days ago
Do you know if Federico Faggin copied the logic design of the 2200 or implemented the ISA using his own design?
2 comments

The implementation of the 8008 is completely different from the 2200 (as is Texas Instruments' forgotten TMX 1795 implementation). It would be extremely inefficient to copy the TTL implementation, since that depended on what chips were available. But the biggest difference is that the Datapoint 2200 was a serial machine that used serial shift-register memory while the 8008 had a "normal" 8-bit datapath.
Thanks - even in 1972 we had multiple radically different implementations of the same ISA!
His own. There would have been no way to fit the logic design of the 2200 on a chip, both because of lack of metal layers, and because the 2200 was designed to be frugal in how many chips it used, using off-the-shelf chips, which is very different from being frugal in the amount of transistors you use when you have freedom to lay out each one by hand.