In article <·····················@cs.rochester.edu> ······@CS.ROCHESTER.EDU (Brad Miller) writes:
>2) The Sparcstation-1 has NO bus whatsoever. Where would you plug an
>embedded Ivory in? The serial port? :-)
>
No bus? This is going to come as a *big* surprise to an awful lot of
people. I wonder where they've been connecting their color
framebuffers...
The SPARCstation 1 has a perfectly good bus. It's called the S-bus.
There are three connectors inside the box for S-bus cards. These
cards need to be roughly 3" by 5", so fitting a Lispm onto one would
be a pretty impressive feat of engineering.
Yep, I misspoke on this one; I just found out there is a proprietary bus for
I/O devices. (Which of course one *could* treat the ivory as, but it would
lose performance wise). I'm amazed; the physical dimensions of the
Sparcstation don't look like it could handle anything of the sort... On it
being proprietary; has Sun published it's specs yet? Anyway, as Hank points
out, obviously existing technology would make a 3"x5" card hard to do, esp.
since one would either have to have local 40bit memory, or a cache to allow
the local processor to get 40bits doing 32bit fetches over the S-bus. I
don't think it would fit but maybe next generation :-)
From: Barry Margolin
Subject: Re: Symbolics co-processor board for the Sparcstation-1 ?
Date:
Message-ID: <28945@news.Think.COM>
Regarding a Symbolics co-processor that fits on the Sparcstation-1's S-bus:
In article <·····················@cs.rochester.edu> ······@CS.ROCHESTER.EDU (Brad Miller) writes:
>obviously existing technology would make a 3"x5" card hard to do, esp.
>since one would either have to have local 40bit memory, or a cache to allow
>the local processor to get 40bits doing 32bit fetches over the S-bus. I
>don't think it would fit but maybe next generation :-)
It shouldn't be TOO long before it's possible. That's only about a
third the size of a Macintosh II NuBus card, and Symbolics has an
Ivory card that fits there. And they've already dealt with the
problem of accessing memory in 48-bit chunks (don't forget the ECC)
over a 32-bit bus in the MacIvory.
Barry Margolin
Thinking Machines Corp.
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