Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!zaphod.mps.ohio-state.edu!mips!dimacs.rutgers.edu!rutgers!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: <21743@cbmvax.commodore.com>
Date: 20 May 91 17:27:54 GMT
References: <1991May13.223251.29436@menudo.uh.edu> <21602@cbmvax.commodore.com> <1991May16.104804.30816@kuhub.cc.ukans.edu>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Organization: Commodore, West Chester, PA
Lines: 28

In article <1991May16.104804.30816@kuhub.cc.ukans.edu> markv@kuhub.cc.ukans.edu writes:
>> 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.  

>Thats a question I've had.  Is there any inherant limit on in Zorro
>III on the number of slots that can be addressed, 

In theory, the only limit is based on the bus loading.  Using F-series or
equivalent loading rules, a Zorro III backplane could theoretically have around 
30 slots, though I think in reality that many could run you into troubles with
the length of the backplane.  And some monster bus controller would be needed
for all those SLAVEn*, BRn*, and BGn* lines.  While Zorro II cards generally 
work in Zorro III backplanes, Zorro II was never required to use F-series 
loading rules, so the number of Zorro II cards that can be used in a Zorro III
backplane is probably somewhere between 5 and 10.  

>and is the A3000 Buster limited to 4 slots, or does it have the silicon to 
>deal with more slots given the right motherboard.

The A3000's Fat Buster can support 5 slots, as it does in the A3000T.  

>Mark Gooderum			Only...		\    Good Cheer !!!

-- 
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.