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From: jlg3@uafhcx.uucp (Jennifer L. Garner)
Newsgroups: comp.sys.amiga
Subject: Re: A2630 questions (for Dave Haynie this time) [REPOST]
Summary: DMA disk speeds...
Keywords: A2630
Message-ID: <3716@uafhp.uark.edu>
Date: 17 Feb 90 01:01:31 GMT
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Dave:

I'm sure you've been asked this a zillion times, but maybe you could be 
patient with a hardware neophyte. Why does the jump from a straight 2000
to a 2500 (2620 or 2630) represent such an incredible increase in the disk
operating speed? I guess I always assumed that the DMA speeds were constant
regardless of processor speed (fixed bus speed). 

I am working on an application that requires the absolute maximum speed on 
reads and writes, regardless of hardware configuration. What methodologies, 
particularly in software, can be used within CBM guidelines to guarantee
full advantage of DMA disk transfers?

We are working on real-time transfer of stereo audio to HD. This will    
require ~100k/sec transfer rate @ 16 bit words (48k per channel). Is this
reasonable to expect from an unexpanded system, or should we demand the use
of a speed up card?

						Don Kennedy 
						Vision Quest