Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!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: A500 Exp. Slot VS A2000 CPU slot ??
Message-ID: <22711@cbmvax.commodore.com>
Date: 26 Jun 91 20:17:32 GMT
References: <1991Jun19.231808.7291@tplrd.tpl.oz.au>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Organization: Commodore, West Chester, PA
Lines: 17

In article <1991Jun19.231808.7291@tplrd.tpl.oz.au> paulg@tplrd.tpl.oz.au (Paul Gittings) writes:

>Looking at the pinouts of the A500 expansion edge connector and the
>A2000 CPU slot, there does not seem to be very much difference between the
>two (mainly an extra clock signal on the A2000).

And the coprocessor interface protocol.  That's essentially unnecessary if
you don't have additional DMA devices, and absolutely necessary if you do.
If you run the BGACK* line of a coprocessor card to +5V, and the BOSS* line
of the coprocessor card to BGACK* of the A500/A1000 edge, and of course make
sure the 68000 and coprocessor are the only two possible bus masters in 
the system, then all you usually have to do is worry about the 7MHz clock.

-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
	"This is my mistake.  Let me make it good." -R.E.M.