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    I have always enjoyed the retroactive mnemonic naming of the registers EAX-EDX (accumulator, base, count, data). It almost makes you believe that the whole thing was actually planned, and not a complete mess of gradual evolution.

    An interesting side note is the Z80, which was basically an evolution of the 8008. It had the exact same basic register names of A, B, C, D, E, H, and L. But they extended the 8008’s idea of pairing H and L to create addresses, much as the 8086 did, and combined six of the 8-bit registers to make three 16-bit registers – so they had the registers BC, DE, and HL. As with the 8086, these were not truly generic, but had different specializations. HL and DE were used and source and destination registers in copy operations, and BC was used as an implicit loop counter. So BC and DE were naturally given the retroactive mnemonics of Byte Counter register and DEstination register, respectively. Almost as if they had planned it that way all along.

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      This was absolutely fascinating to read. More of this, please!