> You may be right.  I had thought that the console monitor and the PAL
> code were lashed together.  The whole thing is a mess.  I'd have
> preferred no PAL code and 001 console monitors.  It's not obvious to
> me that the whizzo VMS queue instructions are actually worth having.

I've got kind of mixed opinions on the subject of the PALcode.  The
multiple console monitors do seem a little pointless.  As near as
I can tell, the main motivation behind multiple PALcodes was to ease
porting VMS from the VAX and DigitalUNIX (or whatever it was called
that week) from the MIPS.  One had a lot of built-in assumptions about
the VAX MMU and the four VAX processor modes and the other assumed
a lot about MIPS.  That naturally led to the usual CS narcotic.  "We'll
just abstract it away with an interface layer."  In retrospect, it looks
to be an unnecessary bit of complexity.  But at least it's vaguely interesting,
unlike say the 7000 variations of how to specify which block you want
from an IDE drive.

BLS


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