[comp.arch] Is the 80960 a supercharged 432?

jimv@radix (Jim Valerio) (04/17/88)

In article <953@ima.ISC.COM> marc@ima.UUCP (Marc Evans) writes:
>it seems to me that the 80960 is just a repackaged, supercharged version
>of the 432. Can anybody comment on this?

This comparison is far from the truth, and yet....

The architecture spec for what is now called the 80960MC was written in
1984 and was based on revision 3.0 of another spec.  Version 0.1 of that
latter spec had a strong 432 influence.  Significant changes were reflected
between major revisions of the specification, and merged into all the
specifications of the instantiations of the architecture.  If you're curious,
revision 7.0 exists, though this one is a less significant difference from
it's predecessor than previous revisions were.

I would be surprised if anyone thinks they see the 432 in the 960KA or 960KB.

What is now called the 80960KA was the next instantiation of the architecture
after the 80960MC, and was written in 1985 and based on the revision 5.0 spec
(if I recall correctly).  Oddly enough, the processor being made available
first (80960KB) was the last architectural family member to be specified (thus
far), and was based on the revision 6.0(?) spec.  This was the first
instantiation that required no reworking of portions of the architecture; it
was truly a hybrid between the 960KA and 960MC.  Given the hints Intel is
dropping at this point, it seems clear that yet another instantiation is in
the works.


And a few miscellaneous tidbits that may as well go here as elsewhere:
(a) Glen Myers did not work on the 432, although Konrad Lai did.  
(b) Konrad Lai is probably the "unsung hero" architect of the 80960.
(c) Reinhold Weicker developed the often-quoted Dhrystone benchmark when he
    was a member of the 80960 architecture group.  (You might think that
    the implementation would be tailored to perform better than it does on it,
    given this. :-)
(d) Another unsung architect is Karl Heinz-Kraus.
(e) I find the tendency towards revisionist history irritating.  Mine
    included.
--
Jim Valerio	jimv%radix@omepd.intel, {verdix,omepd}!radix!jimv