Path: utzoo!attcan!uunet!convex!killer!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!ncar!tank!nic.MR.NET!shamash!raspail!bga
From: bga@raspail.UUCP (Bruce Albrecht)
Newsgroups: comp.sys.nsc.32k
Subject: Re: The 'cost' of a '532 system (Long).
Keywords: cheap nsc 532
Message-ID: <1054@raspail.UUCP>
Date: 23 Nov 88 22:01:39 GMT
References: <433@sdrc.UUCP> <2659@sultra.UUCP> <1041@raspail.UUCP> <2677@sultra.UUCP>
Distribution: eunet,world
Organization: Control Data Corporation, Arden Hills, MN
Lines: 50

In article <2677@sultra.UUCP>, dtynan@sultra.UUCP (Der Tynan) writes:
> Hmm.  Amusing comment at best.  Check the original reference.  *I* was the one
> pushing for an *inexpensive* machine.  I *still* am.  But, one has to look at
> the price/performance curve as well.  On top of that, if there is already an
> organization in place (the '532 Manifesto) to build a '532 system, why go
> in competition to that effort.  What I would like to see, is an overall vote
> or consensus of opinion as to a CPU type.  I am open to comment.  I happen
> to have a 6MHz 32032 chipset in my desk, which is slowly ageing.

If we purchase 532DKs, we can get the '532 and all the necessary support chips
for $532.  It's a 25Mhz '532, which would need approximately 80-100 nsec RAM
for zero wait states.  If the code is tight, we could have a lot run within
the internal cache, which lessens the need for zero-wait state memory.

> > The 532 cost big $$$, the memory to feed the 532 cost big $$$, and the
> > IO capacity to feed the 532 costs, you guessed it, big $$$.  Like the National
> > Semi guys have been saying, if you want a 532, talk to Heurikon, they did it
> > right.
> 
> This is not true.  It may be safe to say that the '532 chip is expensive.
> However, what kind of extortion can we pull on NSC?  On the other hand,
> whether you use a Mips processor or a Z80, the DRAM will be 150ns SIMMS.
> This is fixed.  Nothing to do with the CPU speed.  If you want to avoid
> wait-states, just use the "paging scheme" hinted at by Steve Wilson.  This
> should give you the 50ns eaten by the MMU at least.  And this is without
> using 15ns cache chips.  Furthermore, since when did I/O feed the CPU.
> The '332 and '532 (and maybe even the '032 -- Steve??) allow dynamic
> resizing of the bus.  In this way, the CPU could access a vanilla IBM-PC
> bus, without major surgery.

Do you lose 50 ns with the '532's internal MMU?  I won't be getting a copy of
the new databook with the '532 specs for a couple weeks, so I can't check it
out.  My local 32k specialist said that a 25 Mhz 532 should be able to get by
with fairly slow speed RAM.

If we make a decision to use the 532, we can get the designer's kit for $532
through February.  A well designed board should allow either you to start
with 256K or 1M SIMMs, so the people who can afford more can buy them.
If we were interested in providing ECC, we could use the NS ECC chip, and
use 5 (256K/1M)x8 SIMMs, and have a spare bit.

I, for one, would not even consider building a 32016/32 system, even though
it was cheap.  I think we could build a high-performance '532 system for about
$1k more than the ultra-low end machine, depending on how much memory and other
"frills" like big disks get added.  If the box with a '532, 1M of memory, and
40M disk drive costs about $2k, then we've got a system competitive with the
'386 machines in performance and '286 machines in price, and for half the
cost of a Mac II.

Bruce