Reply to post: Re: What we need @PeterGathercole

ZX Spectrum reboot latest: Some Vega+s arrive, Sky pulls plug, Clive drops ball

ThomH Silver badge

Re: What we need @PeterGathercole

I think you're off by one; the shortest 6502 instructions take two cycles, and the most common ones — those which read from or write to the zero page — take three.

But the issue in a real machine is that a 6502 uses only half a clock cycle to perform an entire memory access whereas the Z80 uses at least two. So pick your clock speed as a function of those constraints and your memory speed.

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