🚀 go-pugleaf

In <slrn5v252s.2o.jdege@jdege.visi.com>, jdege@jdege.visi.com (Jeffrey C. Dege) writes:
>On Tue, 12 Aug 97 08:05:15 -0400, Brandon S. Allbery KF8NH; to reply, change "void" to "kf8nh" <bsa@void.apk.net> wrote:
>>
>>The 68000 had 32-bit internal address and data, 24-bit external address, and
>>IIRC 16-bit external data.  The easiest way to deal with it was as a 16-bit
>>processor, although you could treat it as a 32-bit processor if you were
>>careful about the upper 8 address bits.  Early 68000 software used it as a
>>16-bit processor, later software generally ("pay no attention to that
>>TRSDOS-12 behind the curtain" --- nobody else did :-) used it as a 32-bit
>>processor.
>
>The 68000 moved data out to the bus 16 bits at a time, but all of the
>instructions were 32 bit, all of the addressing was 32 bit, etc.
>
>The 80386 was a 32-bit chip designed to be compatible with preceding
>16-bit chips, and was an ugly kludge.  The 68000 was a 16-bit chip
>designed to be compatible with a succeeding 32-bit chip, and as
>a result, the 68020 was very cleanly designed (and ran 68000 code
>with none of the ugly compromises that the 80386 resorted to to
>run 8086 code.)

The original 8086/88 was designed to be somewhat compatible with the
8085/8080.  In 1981, I had some 8085 assembler that I needed to
move to an 8086 base.  Intel had a program that did the majority
of the conversion.  Because of this compatibility, the 8086/88 was,
even for the time, an ugly processor.  However it was much better
than the awful RCA 1802(an UGLY architecture).  New Pentiums are
still ugly, architecture wise.

My favorite processor would have to be the National 16000/32000.
They took everything wrong with the 68000 architecture (and there
wasn't that much wrong with it), and cleaned it up.  I don't
even know if National makes it anymore, but, when I was working
in printers, they made a sales call, and had 320xx processors
optimized for laser printers, with hardware bit-blit among
other features.

Bob Plyler       IBM 3890/XP Engineering

not an official IBM spokesperson