[self-correction of terrible, embarrassing technical howler]

At 2026-10-26T13:55:20-0500, G. Branden Robinson wrote:
> Ease of understanding is not particularly correlated with creative
> effort.  Assembly language mnemonics are not readily understood by
> most people in the world, but they tend to perform operations so
> simple that they are not copyrightable.  If that weren't true,
> microprocessor architects could not clone another manufacturer's CPU.

<loud buzzer sounds>

This is of course not true.  Microprocessors decode instruction formats,
not assembly language mnemonics.

Microprocessor programmer's manuals invariably (in my experience) list
mnemonics alongside instruction formats.

Possibly the fact that assembly is useful primarily for human-to-human
communication is why Intel thought they could plant a stake in the
copyrightability of a set of mnemonics.

> For a time in the 1970s, Intel Corporation claimed copyright in
> assembly language mnemonics themselves, considered separately from the
> machine language instructions they represented.  That's why the Intel
> 8080-compatible Z80 microprocessor by Zilog used different mnemonics,
> such as "LD" and "ST" instead of "MOV".  However, Intel proved unable
> to sustain this position.[B]

I looked into this, and while not dispositive (nor likely the sole
factor), apparently Intel lost a lawsuit against NEC regarding its V20
(enhanced) clone of the 8086.

Maybe other folks can throw some light on the issue.

Regards,
Branden

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