Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!bagate!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Either a really dumb or a really cool A3000 hack idea
Message-ID: <21602@cbmvax.commodore.com>
Date: 15 May 91 16:38:42 GMT
References: <1991May13.223251.29436@menudo.uh.edu>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Organization: Commodore, West Chester, PA
Lines: 21

In article <1991May13.223251.29436@menudo.uh.edu> jet@karazm.math.uh.edu (J Eric Townsend) writes:

>Why not have a Zorro III bus extension thingie?  Like a cable from 
>a ZIII slot to another cardcage (maybe stuck under a raised A3000 case).

That wouldn't work.  These things were reasonably doable with the original
PC-XT bus, but a Zorro III bus transaction may be going 5x-10x faster than 
an XT bus cycle.  That's not going to be too happy over ribbon cable.

Aside from speed issues, there are signal issues.  The XT bus is a "pure" bus;
each slot is like the next, all wires are shared (eg, bused) from one slot to
the next.  The Zorro III bus isn't purely bused.  There are three signals per 
slot that are unique to that slot and have to be managed by the bus controller, 
which on the A3000 is the Buster chip.  

>J. Eric Townsend - jet@uh.edu - bitnet: jet@UHOU - vox: (713) 749-2126

-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
      "That's me in the corner, that's me in the spotlight" -R.E.M.