Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!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: HARDWARE HACK: 2630 accellerator card in a Zorro II slot
Message-ID: <21815@cbmvax.commodore.com>
Date: 22 May 91 21:38:01 GMT
References: <72302@microsoft.UUCP> <21607@cbmvax.commodore.com> <1991May16.063945.7032@Informatik.TU-Muenchen.DE> <21643@cbmvax.commodore.com> <1991May21.161508.7078@sagpd1>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Organization: Commodore, West Chester, PA
Lines: 51

In article <1991May21.161508.7078@sagpd1> monty@sagpd1.UUCP (Monty Saine) writes:
>In article <21643@cbmvax.commodore.com> daveh@cbmvax.commodore.com (Dave Haynie) writes:
>>A1000 or A500.  While these machines don't have the coprocessor interface, that
>>isn't an issue unless there's other DMA around.  So the CBR/CBG lines can go
>>directly to the BR/BG lines of the 86 pin edge (they naturally correspond,
>>anyway).  There is no /BOSS line on the 86 pin edge, but there is /BGACK, which
>>again, in the absense of any other 68000 style DMA, can be used.  This requires

>    Dave,
>    Does this mean a DMA device not on the accelertor, or no DMA at all? I guess
>    what I am asking is how the new GVP all in one '030/SCSI/RAM board would
>    adapt to this scheme. Is it possible with out major hacking? 

I don't know that much about how that did the GVP board, but I think that it 
pretty much has to resolve any bus mastering between 68030 and DMA controller
on-board.  That would imply that it should work just dandy hooked up in this
way.  That is, of course, only a guess, but I can't really see how they would
have done it differently, unless they're madmen or something.

>    So far all I've seen in this hack is some connectors and a minor bit of 
>    wiring. 

Careful building of connectors and wiring, I might add.  We're talking about
running most of the 68000 bus somewhere, and that bus doesn't want to go very
far, otherwise it picks up noise, capacitance, inductance, and all kinds of 
dirty, mean, nasty stuff that makes it not work any more.

>    This type of board would eliminate needing the expansion chassis in most 
>    cases. It might be an interesting exercise to hack the GVP board to an 
>    A500/A1000. 

Yeah, it might just work.  You know, technology does march on.  What used to
take a whole box could very well fit on a single card.  In fact, that's kind
of the idea of the A3000 in the first place.  We reached the point at which 
it made sense to integrate the whole 32-bit/68030 system, rather than provide
it as an add-on.  So the A3000 can handle more on the motherboard than most
people hooked up to their A2000 or A500.  The new GVP card probably isn't much
behind in levels of integration, I guess they do even offer memory over the
basic 8Meg expansion of the A2000/Zorro II setup.  Since you could build such
a connector without harming your A500 or GVP, it would be an interesting 
experiment.  I imagine you'd need a power supply improvement for an A500, but
probably not for an A1000 (though that guy at GVP still holds the record for
power consumption on 2Meg Zorro II RAM cards, and probably always will...).

>    Monty Saine


-- 
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.