Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: are all memory boards compatible with 68020 boards?
Message-ID: <10267@cbmvax.commodore.com>
Date: 20 Mar 90 18:32:13 GMT
References: <6691@ncar.ucar.edu>
Reply-To: daveh@cbmvax (Dave Haynie)
Distribution: usa
Organization: Commodore, West Chester, PA
Lines: 29

In article <6691@ncar.ucar.edu> sitongia@hao.ucar.edu (Leonard Sitongia) writes:
>I'm thinking about getting either the Microbotics 8-UP! or SupraRam2000
>memory boards.

I'm pretty sure either board works just fine.  I've seen a SupraRam2000 used
with some of the 32 bit systems, and I have an 8-UP in the lab which runs like
a champ.

>Are they compatible with the A2620 board?  What are the constraints on
>memory not on the coprocessor board, that allow the 68020 to use the
>memory.  

Almost all of the constraints are on the Coprocessor board.  The Coprocessor
board must fully emulate a 68000 for any off-board memory cycles.  As long as
an expansion card is designed to the actual bus specifications (rather than
the observed behavior of the bus, eg, what just happens to work) the expansion
card should work in all Amiga backplanes with all Amiga coprocessors.

>I guess the memory has to be faster than some rate.

No, the Coprocessor card inserts wait states to access the expansion bus 
memory.

>-Leonard E. Sitongia    System Manager		 (303) 497-1509

-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
                    Too much of everything is just enough