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    As it stands the POWER ISA has a decently comprehensive ecosystem, with a reasonably wide ranging instruction set. I’m curious as to whether this includes some of the PowerPC stuff still used in embedded systems or whether that stuff is covered by FreeScale (Motorola) IP.

    I do think designing a POWER CPU would definitely be a fun exploratory project now that all of the stuff is openly available though.

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      My thinking is this is just OpenPOWER (i.e., POWER8 and up). But I’d be delighted to be wrong.

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        You mean cores or instructions? I haven’t been in PowerPC in over a decade, but I remember PowerPC being a subset of POWER in terms of ISA.

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          In the 32-bit era, yes. However, 64-bit PowerPC and Power ISA are pretty much synonymous. The classic example is the G5, which is truly a member of the PowerPC family (“PowerPC 970”), but is a 64-bit processor basically consisting of a POWER4 with an AltiVec unit bolted on. You can see this in the instructions, for example (no mcrxr, no dcba, 128-byte cache line behaviour with dcbz, exactly the same as this POWER9).

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            That makes a ton of sense. Thanks for the history lesson!

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            Instructions. AFAIR the embedded versions of PowerPC add a bunch of instructions and other architectural features to support hardware things, but you might be right.

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          This is really neat and kinda trippy. Perhaps I’m slightly unobservant, but I didn’t notice an explanation as to what the area (size) of the hexagons represented?

          I really liked the sounds though. I added a little reverb on my system while playing both this and some house music in the background and they really complemented each other.