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A comment on I Ported SAP to a 1976 CPU. It Wasn't That Slow. Parent comment

Re:I Ported SAP to a 1976 CPU. It Wasn't That Slow by michalpleban on Wednesday July 09, 2025 @05:45PM (#44515029)
Input and output are in a separate address space on the Z80. It's on the 6502 where they share space with code and data.
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Re:I Ported SAP to a 1976 CPU. It Wasn't That Slow by theamk on Friday July 11, 2025 @04:03PM (#44536317)
what do you mean?

Memory and i/o ports are in separate address spaces in Z80, but for use cases described in post ("dot product for 1536-bit vectors") i/o port space does not matter, it's all memory - and there is just a single address space there.

(Granted, some Z80-based systems had funky paging setup, but author makes no mention of those, they just say generic Z80 - and that means total 64KB for code, input data, cache and output data)

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