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From: whitewolf@gnh-starport.cts.com (Tae Song)
Newsgroups: comp.sys.apple2
Subject: Re: My DMA SCSI question
Message-ID: <0093B284FE618EA0.00000111@dcs.simpact.com>
Date: 14 Aug 90 08:01:16 GMT
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X-Unparsable-Date: Sun Aug 12 90 at 05:08:48 (EDT)

Although I could be wrong, I don't think 1:1 interleave is the best for Apples
DMA SCSI card.  It's probablely best to try out different interleaves though.

MFM has 17 sectors per track, RLL has 28 (normally) and up to 34 sectors track
and there's one drive with 47 sectors per track.  Now, RAMFast is the only
controller that can handle that much data that fast.  I know Apples DMA can't
do 1:1 on RLL drives.  MFM drives maybe 1:1 or 2:1.

I don't think the DMA SCSI cards come with low-level formatting programs, so
you might have to dig out that old rev C card and low-lwvwl format starting
from, I would guess 8:1 and go down to 1:1 and testing it with the DMA SCSI
card.  I know it's a pain, but it's the only way I can think of finding the
ACTUAL optiunim interleave.