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Date:      Fri, 23 Jul 2010 17:12:35 -0700
From:      perryh@pluto.rain.com
To:        holm@freibergnet.de
Cc:        freebsd-stable@freebsd.org
Subject:   Re: Floppy driver broken on 8.1-PRERELEASE?
Message-ID:  <4c4a2ff3.t5Wfu61In0E4%2BQtF%perryh@pluto.rain.com>
In-Reply-To: <20100723101924.GB96573@pegasus.freiberg-net.de>
References:  <20100723101924.GB96573@pegasus.freiberg-net.de>

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Holm Tiffe <holm@freibergnet.de> wrote:
> Why I can't read 1440K blocks from the floppy anymore?

Perhaps something changed in the DMA driver, such that it is
no longer able to handle a request exceeding 65K (which was
the hardwired limit of the "original" PC DMA controller).

I've long used bs=120b for floppies, and never had a problem.
Why 120?

# 120*512 = 61440, which is less than 65K.

# For both 1.2MB and 1.44MB floppies, 120 sectors is a multiple
  of the track length.



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