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Posting-Version: version B 2.10.2 9/17/84 chuqui version 1.7 9/23/84; site nsc.UUCP
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From: chuqui@nsc.UUCP (The Phantom)
Newsgroups: net.micro.16k
Subject: Re: Corrigenda
Message-ID: <2402@nsc.UUCP>
Date: Tue, 26-Feb-85 14:08:51 EST
Article-I.D.: nsc.2402
Posted: Tue Feb 26 14:08:51 1985
Date-Received: Wed, 27-Feb-85 06:19:40 EST
References: <2385@nsc.UUCP> <344@desint.UUCP>
Reply-To: chuqui@nsc.UUCP (The Phantom)
Organization: The Paradise
Lines: 48
Summary: 

In article <344@desint.UUCP> geoff@desint.UUCP (Geoff Kuenning) writes:
>(a) 32 bits is a bit less than five Eagles worth of byte-addressed data.  I
>    can easily concoct a microprocessor application where direct addressing
>    of that data space is desirable, if not necessary.  It won't be UNIX, of
>    course.
>(b) In any case, there are several address widths between 24 and 32.  What if
>    I need 17 megabytes of virtual space?  I just saw a thing go by on
>    unix-wizards that talked about running 60 MB processes - that takes 26
>    bits.

I think we're dropping down into nit-picking. I can easily come up with
microproccessor applications where the 1802 is better than the 68020, where
the 8088 is better than the 6502, where the Vax is better than an electric
toaster. It is easy to come up with a refutation for any hardware setup.

The reality of the situation is that it is hard to cost justify a system of
the power of a 32xxx with more than about 4megabytes of memory, simply
because the memory takes up board space, eats power, generates heat, and
generally costs a lot. Until the 256K chips come down in price to something
reasonable, megabyte memory boards are about the limit you'll see on most
systems, and you won't see more than a couple. When megabit chips show up,
you'll start seeing larger memory spaces available. The only systems today
that cost justify more than about 2 to three megabytes of memory are in the
100K and up cost (say, a Vax) and there are few running more than about 8
Megabytes of memory at all (a few vaxen and the mainframes). 

The 32032 has a full 32 bit data path. All internal paths are 32 bit. The
addressing is 24 bit, but it is handled as a 32 bit path internally so
there won't be any suprises in the software moving up to a full 32 bit
address path when it shows up, and it is on the drawing boards. The point
is, in the markets the 32000 series stuff is aimed at, the only real
advantage going to a 32 bit address path now would give us would be
marketing. The disadvantages include a larger package with more pins, a
more expensive part, using more board space, controlling logic, and power,
and increasing manufacturing costs both at the chip and the board level.
We'll have the addressing when we need it, but we don't really need it now.

sigh. Haven't we beaten this into the ground? Anyone got a new topic they
want to discuss?

chuq von rospach
national semiconductor, santa clara
(408) 733-2600 X242
-- 
From behind the eight ball:                       Chuq Von Rospach
{cbosgd,fortune,hplabs,ihnp4,seismo}!nsc!chuqui   nsc!chuqui@decwrl.ARPA

We'll be recording at the Paradise Friday night. Live, on the Death label.