Article View: comp.sys.atari.st
Article #3380Re: HELP IDENTIFYING SEAGATE 296N WITH REV. 7 ROM
From: Stephen Jacobs
Date: Fri, 25 Aug 1989 14:05
Date: Fri, 25 Aug 1989 14:05
31 lines
2378 bytes
2378 bytes
In article <5440048@hplsla.HP.COM>, andyc@hplsla.HP.COM (Andy Cassino) writes:
(Replying to the statement: )
> |
> | My only comment about the Seagate 296N is that it was supposed to
> | be a 1:1 interleave drive, and people paid money for that spec.
> | As far as I know, Seagate has yet to deal fairly with its customers
> | who purchased the ROM8 version of the 296N.
> |
>
> Well, the ROM 8 does format 1:1, and an ST can read it, though it's doggo-slow.
> The optimum interleave for any computer/controller/disc combination is
> not always 1:1!
This is true, but cheating on meanings. When one says that a disk with
built-in controller can be formatted for 1:1 interleave, the normal expectation
is that this means the controller will be able to deliver consecutive sectors
to a DMA device without read errors. In other words, you can read a whole
track in one revolution if your computer is fast enough. The ST 296N can't
do this (Rev 8 ROM). It has nothing to do with the computer. The optimum
interleave for a single magnetic disk on a system is the tightest interleave
that doesn't give frequent failures (for small interleave ratios, at least:
note that I said for a single disk). The ST 296N gives something like 50%
failures when you try to read consecutive sectors consecutively, and a few
failures when you try to read alternate sectors consecutively (2:1 interleave)
Given the ordinary usages of words, that means it doesn't support 1:1
interleave.
All this is against the background that I have an ST 296N (formatted for
2:1 interleave), I like it very much, I recommend it as about the best buy
around in disk drives and I rescued a friend who was mad at his ST 296N (on
a PC compatible) with 1:1 interleave (he finds 3:1 better than 2:1).
Steve J.
Technical Details
Message-ID:
<9355@chinet.chi.il.us>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!uunet!wuarchive!brutus.cs.uiuc.edu!apple!amdahl!pacbell!att!chinet!sajReferences:
<2520@orion.cf.uci.edu> <5440048@hplsla.HP.COM>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!uunet!wuarchive!brutus.cs.uiuc.edu!apple!amdahl!pacbell!att!chinet!saj From: saj@chinet.chi.il.us (Stephen Jacobs) Newsgroups: comp.sys.atari.st Subject: Re: HELP IDENTIFYING SEAGATE 296N WITH REV. 7 ROM Summary: Let's play Humpty Dumpty with words Message-ID: <9355@chinet.chi.il.us> Date: 25 Aug 89 14:05:27 GMT References: <2520@orion.cf.uci.edu> <5440048@hplsla.HP.COM> Organization: Chinet - Chicago, Ill. Lines: 31