• umbraroze@lemmy.world
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    7 months ago

    NOP is $EA, of course, and… um…

    …sorry, I’m just a Commodore 64 scrub, I don’t know nothing about this high and mighty Intel 8086 nonsense.

    [looking up]

    …it’s 0x90 on IA-32? WHAT? Someone told me every processor used 0xEA because that was commonly agreed and readily apparent. …guess I was wrong

    • Flying Squid@lemmy.world
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      7 months ago

      My daughter told me the other day, “I bet I could figure out a Commodore 64 if I had one.”

      Good luck figuring out LOAD “*”,8,1 by yourself, kid.

    • palordrolap@kbin.social
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      7 months ago

      Someone told me every processor used 0xEA

      Not sure if this is a riff on the joke or not.

      Back in the day I dabbled in 6510 code, and up until today hadn’t even bothered to look at a chart of opcodes for any of its contemporaries. Today I learned that Z80 uses $00 for NOP.

      Loth as I am to admit it, that actually makes sense. Maybe more sense than 65xx which acts more like a divide-by-zero has happened.

      The rest of the opcode table was full of alien looking mnemonics though, and no undocumented single byte opcodes? Freaky, man.

      But the point is that not even Z80 used $EA. If the someone was real they probably meant every 65xx processor.