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Re: /etc/disktab on vax

>> IIRC the Z80 required a 4x clock, so a 20MHz Z80 is about as fast as
>> a 5MHz 8080 or 8085.
> It's not that the Z80 "requires a 4x clock", but four T-states (clock
> cycles) make up one machine cycle.  [...]

Also - and this memory is seriously fuzzy, so it could be entirely
wrong - I think the 8080 required a two-phase clock, so that there are
four, not two, state changes on the clock pins per clock cycle.  This
could easily turn into "requires a 4x clock", so if my memory is right
and the Z80 copied that particular bit of design....

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