3 ms·
I don’t think an unmodified 6502 would get faster; it assumes memory is fast enough for its clock speed, and won’t, for example, prefetch code or data. Also, i
by Someone 3y ago
I don’t think an unmodified 6502 would get faster; it assumes memory is fast enough for its clock speed, and won’t, for example, prefetch code or data.
Also, if you add a modern-sized cache, you won’t need the memory at all in a single-CPU system; the cache would easily be larger than the addressable memory.
- vidarh 3y agoIt'd only benefit if the latency of the external memory is bad enough to keep the cores waiting, sure, and certainly you're right regarding a single-CPU system. I think this fantasy experiment only "makes sense" (for low enough values of making sense) if you assume a massively parallel system. I don't think it'd be easy (or even doable) to get good performance out of it by modern standards - it'd be a fun weird experiment though.
- Someone 3y agoIf I were to build a system with lots of 6502s, I think I would build something transputer-like, so that each CPU has its own memory, and the total system can have more than 64 kB of RAM. The alternative of a massively parallel system with shared memory, on 6502, would mean all CPUs have 64 kB or memory, combined. I think that will limit what you can do with such a system too much.
- vidarh 3y agoSee: https://news.ycombinator.com/item?id=37011671 https://news.ycombinator.com/item?id=37011671 These were intended to get to 4k cores (but 32 bit), w/32K on-die memory, but the ability to read from/write to other cores. A 6502 inspired variant would be cool, but to not get killed on the cycle cost of triggering reads/writes you'd probably want a modified core, or maybe a 65C816 (16-bit mostly 6502 compatible).