Subject: Re: Floppy driver (was: Re: This week's NetBSD/amiga changes)
To: None <>
From: Michael L. Hitch <>
List: amiga-dev
Date: 04/11/1994 16:21:08
On Apr 11,  2:59am, Ty Sarna wrote:
> Also, I'd have to look at the fd.c source again, but I don't think it
> does HD mode correctly right now. It needs to re-read the ID whenever
> the disk changes (which isn't detected, so I guess it has to be done on
> every track read or write? ewww... Actually, maybe it only needs to be
> checked on open. Hmm... yeah I think that would work.) Applogies if the
> driver already does that.

  I think it does.  The open routine calls fd_probe, which re-reads the
ID.  It also sets the current cylinder to -1, which forces a recalibrate
on every open (it took me a while to figure out why the drive recalibrated
every time ran dd on it).  A rather nasty thing that can happen is that
when the ID is read, the drive gets deselected, but doesn't update the
drive tables.  If the drive motor was turned off, the recalibrate works
fine, but if you access the drive before the motor-off timeout occurs,
the fd_probe deslects the drive and when the recalibrate tries to seek
to track 0, it never sees it because no drive is selected.


Michael L. Hitch			INTERNET:
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