[cctalk] Re: Z80 vs other microprocessors of the time.

[Paul Koning via cctalk]

> On Apr 22, 2024, at 4:21 PM, Mike Katz via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> Once CPUs became faster than memory the faster the memory the faster the CPU 
> could run.
> 
> That is where CACHE came in.  Expensive small high speed ram chips would be 
> able to feed the CPU faster except in case of a cache miss and then the cache 
> had to reload from slow memory.  That is why multiple cache buffers were 
> implemented so one could be filling (predicatively) while another buffer was 
> being used.

An early cache, though not called that, is the track buffer in the ARMAC, a 
1955 or so research computer built at CWI (then called MC) in Amsterdam.  Its 
main memory was a drum, like its predecessors, but it would keep the most 
recently accessed track in memory (core?) for fast access.  That was handled in 
hardware if I remember right, so it's exactly like a one-entry cache with a 
line size of whatever the track length is (32 words?).

        paul