Path: utzoo!attcan!uunet!zephyr.ens.tek.com!uw-beaver!ubc-cs!cheddar.cc.ubc.ca!panon
From: panon@cheddar.cc.ubc.ca (Paul-Andre Panon)
Newsgroups: comp.sys.amiga
Subject: Re: Non-Zorro slots in the Amiga 3000
Keywords: 3000 slots
Message-ID: <5951@ubc-cs.UUCP>
Date: 12 Dec 89 04:45:39 GMT
References: <5906@ubc-cs.UUCP> <3751@convex.UUCP> <5936@ubc-cs.UUCP> <3854@convex.UUCP>
Sender: news@cs.ubc.ca
Reply-To: panon@cheddar.cc.ubc.ca (Paul-Andre Panon)
Distribution: na
Organization: UBC Computing Centre, Vancouver, B.C., Canada
Lines: 38

In article <3854@convex.UUCP> swarren@convex.COM (Steve Warren) writes:
>In article <5936@ubc-cs.UUCP> panon@cheddar.cc.ubc.ca (Paul-Andre Panon) writes:
>>In article <3751@convex.UUCP& swarren@convex.COM (Steve Warren) writes:
>
> [discussion of how to get 32-bit connections while allowing zorro II
>  boards to plug into the same slots]
>
>>%This technique is already being used in "blue" land.  Yes, they do
>>%manage to do some things right out there, and I think this is a
>>%good example.
>
>>I guess you mean the EISA kludge. Sorry, I don't consider it "doing it right".
>
>Depends on what you mean by "it".
>
>--Steve

Sorry (again :-). You effectively said that you thought the two level connection
EISA uses is one of the things "they" managed to do correctly in Blue land. Most
of the reviews I'd heard about EISA weren't exactly-shall I say-raving. I can't
remember the exact points. One that occurs to me is that you would need extra
circuitry so that-should somebody not push in a card far enough so that, if the
lower level fingers are in contact with the higher level contacts, the board and
machine don't get fried from juice going the wrong way. If something can go
wrong, it will. I find the AT or MCA type extension more esthetic and less
mechanically error-prone, and the mechanics of the extension is, after all,
what's involved isn't it? You might have greater crosstalk at high frequencies
with the EISA design too, no? I seem to remember that was part of the reason
why so many of the lines in MCA are have to be ground.

Hopefully I haven't put my foot too far in my mouth and won't wind up saying
sorry in this thread again.

--
      Paul-Andre_Panon@cheddar.cc.ubc.ca      or      USERPAP1@UBCMTSG 
or    Paul-Andre_Panon@undergrad.cs.ubc.ca    or      USERPAP1@mtsg.ubc.ca
"What should the role of the University be? It should be to enlighten Society."
  -Luis Sobrino