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From: jwl@Feanor.Stanford.EDU (John Lockhart)
Newsgroups: comp.sys.amiga
Subject: Re: GVP 68030 reviewed in Sentry
Summary: A2090 controller and the 030 cache (...?)
Keywords: A2090, hard drive, DMA, 68030, cache
Message-ID: <9831@polya.Stanford.EDU>
Date: 8 Jun 89 22:59:59 GMT
References: <2461@van-bc.UUCP> <7069@cbmvax.UUCP>
Sender: USENET News System <news@polya.Stanford.EDU>
Reply-To: jwl@Feanor.Stanford.EDU (John Lockhart)
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In article <7069@cbmvax.UUCP> daveh@cbmvax.UUCP (Dave Haynie) writes:
>DMA into CHIP memory is a very losing proposition.  The data cache is your
>choice.  I'd recommend keeping it off in a DMA system until you get a
>device driver that definitely supports cache flushing.  Programmed I/O
>with an '030 isn't much slower than DMA if it's over the bus, and if it's
>on a magic 32 bit bus like GVP's on-card controller, it's probably about as 
>fast as 16 bit DMA currently is.
>
>Note that, chances are, you'll get away with DMA and the data cache MOST of
>the time.  Of course, Murphy will tell you the times you won't....
>Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"

Um, Dave, I have a CBM A2090 with two ST506 hard drives.  I'm also
interested in putting a GVP '030 or CBM A2630 on my system to improve
performance.  Do you know when Commodore will be revising the 2090
driver to deal with the 68030 cache?

Or, :-(, should I wait for the Amiga 3000?  [I'll probably get one
eventually anyway...  What will the 3000 have for specs?]

  -- John

-------------------------------------------------------------------------------
                         -- John Lockhart
               jwl@feanor.stanford.edu  BIX: jlockhart