Just to be clear, INS is National Semiconductor a.k.a. "NS". I
don't recall NEC (Nippon Electric Corp) being a big player in the
U.S in the late 70's, but maybe they were. I would expect that NS
could easily have been an official second-source (often a
requirement for Military/Government contracts), and thus the chip
was likely identical to Intel's. Conjecture, of course.
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