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Tom Jennings, the creator of fidenet, is producing a nice modern Z80 computer[0] 0. https://www.ebay.ie/itm/206496219323
Why I have not picked one up yet… I think I just have a sweet spot for the 6502 and keep putting together KIM-1 kits.
(EDIT: Finally after years, I just pulled the trigger on their Classic II kit.)
A paragrap from the linked articale Z80 was the choice of a microprocessor for then home computers such as Radio Shack TRS-80, SORD M23P, M5, Sinclair ZX81, ZX Spectrum, KayPro II, and many other manufacturers.3 It was capable of running the CP/M operating system in most Z80-based PCs. Z80 had a reasonable share in the PC market until Intel revealed its 16-bit microprocessor in the mid-1980s. Z80 was very popular as…
Tom Jennings, the creator of fidenet, is producing a nice modern Z80 computer[0] 0. https://www.ebay.ie/itm/206496219323
Ironically (and sadly) the Z80 was discontinued not very long after this piece was published.
This sentence threw me a little bit. Which mainframes were based on the Z80? I'd love to know more about that.
Due to its simplicity it's a fun little processor to program. Hacking on some assembly on a ZX spectrum emulator is a nice way to stay sane in this high abstraction LLM age.
"Simple" is really not a word I would associate with the Z80 ;) The ISA is quite messy because of the backward compatibility requirement with the Intel 8080 (e.g. the Z80 had to fill undocumented gaps in the 8080 opcode encoding map with new instructions, four of which were prefix instructions to unlock additional instruction 'subsets' (DD/FD for replacing instructions involving the HL register pair with indexed addr…
That's an interesting idea. They were previously part of the team that designed the 8080 so they must have been very familiar with the ISA and the design philosophy.
I'm sure they'd be able to come up with improvements but how much more elegant it would have been is hard to say.
interesting to be reminded that an 8080 (8 bit datapath) took 4,800 transistors an Apple M5 Max is 100,000,000,000 transistors (ok it’s 18 CPU + 40 GPU cores) by comparison so 17 million 8080 equivalents
At, ballpark, 1000 times the clock frequency. It’s a pity we do not how to connect such a large number of tiny cores in a way so that it can perform meaningful work. One hurdle is that, even ignoring the insane amount of connections needed, it would not be possible to connect each of those cores to each other one because their address spaces are so tiny.
> Then, as a young engineer, I worked in a large mainframe computer system based on Z80. This sentence threw me a little bit. Which mainframes were based on the Z80? I'd love to know more about that.