Floating point hardware/software

[Steve Neighorn]

In article <682 at amelia.nas.nasa.gov> wgreene at amelia.nas.nasa.gov (William H. Greene) writes:
>
>                      Weitek 1167
>
>     A lot of companies are talking about this coprocessor board. Is
>there anyone out there actually using it under Unix/Xenix ? Are there
>versions of Unix/Xenix that support the 1167 available now ? I know
>that Microport 2.2 does not but I've heard rumors about it being 
>supported in the future. I saw an announcement from SCO about 1167
>support in an upcoming version of Xenix. Microway says that they are
>running the 1167 with a pre-release version of ATT Unix. I've heard
>rumors of overheating with the 1167 and when I look at Compaq's
>mechanical design of their board with the massive heat sink at the
>top, I tend to wonder more. Anyone have any experiences with this ?

Regarding the overheating of the 1167 chip : It can be a problem, and
those vendors who are not placing the 1167 chip set/80387 board in a
heavily heatsinked vertical arrangement may encounter serious heat
problems. A case in point : The Everex Step 386/20 machine uses one
of the familiar 1167/387 sockets (the kind where the 387 sits one
pin row in on every side) and places it directly below the left-hand
hard drive bay. I know one installation at Tektronix that installed
both the 387 and the weitek board, and the machine would work for
a few minutes before crashing. The kludge solution was to cut a hole
in the case and add a separate muffin fan blowing directly on the
coprocessor board. This solved the heat problem, made a mess of
the case, and proved that the 1167 is hot in more ways than one.

Rumor has it that Everex is changing their motherboard arrangement 
on the Step 386/20, and going with an arrangement similar to that
of Compaq.

Regarding 1167 support and 386 Unix:
The Green Hills C-386 C compiler has two flags referring to the 1167.

-X143 specifies the generation of Weitek floating point code instead
of 80387 code.

-X213 specifies using the Weitek software emulation library, and
requires -X143 to work. 

My GHC manual states that V/386 does not support the Weitek
math coprocessor at this time, but that it will be supported in
a future release. The version of C-386 I have is 1.8.3A.
-- 
Steven C. Neighorn            !tektronix!{psu-cs,reed,ogcvax}!qiclab!neighorn
Portland Public Schools      "Where we train young Star Fighters to defend the
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