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Date:      Sun, 27 Aug 1995 22:27:12 -0700 (PDT)
From:      sos@freebsd.org
To:        jdl@chromatic.com
Cc:        freebsd-current@freebsd.org, joerg_wunsch@uriah.heep.sax.de
Subject:   Re: That IDE CD ROM thang again...
Message-ID:  <199508280527.WAA01708@freefall.FreeBSD.org>
In-Reply-To: <199508261347.IAA25153@chrome.onramp.net> from "Jon Loeliger" at Aug 26, 95 08:47:50 am

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In reply to Jon Loeliger who wrote:
> 
> > I think it's in error to byte-shuffle only the ID string.  Everything
> > from the drive must be byte-swapped, including the ID word and all
> > data.

Ahem, my own obseravtions suggests that it is only "some" fields
that require swapping, depending on model...
 
> Oh my!  OK, I'll give this a hack attack and see what I get.  Any chance
> you can give me a one minute pointer to *where* that might take place?
> Like, where the buffers coming back from the drive are filled?  I see
> the one in _probe() that's obtained with the insw().  Will they all
> look like that?
> 
> >  (Of course, you have to make a distinction whether to swap or
> > not before.)
> 
> Yea, this is curious.  I get the feeling that some people are able
> to get the IDE CD drives to work and others aren't.  Is there some
> reasonable distinction separating the two camps?  Do we need to start
> a collection of working/not-working drives and form the basis of a
> boot time lookup table (ick) to determine byte-swapping needs?

Yep, we need a table of known drives...

(Actually this is a case where the DOS'mers have an advantage -
they get a driver with the drive, that knows its little secrets :)


-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Soren Schmidt  (sos@FreeBSD.org | sos@login.dknet.dk)  FreeBSD Core Team
               So much code to hack -- so little time



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