Floppy driver broken on 8.1-PRERELEASE?

perryh at pluto.rain.com perryh at pluto.rain.com
Sat Jul 24 00:14:00 UTC 2010


Holm Tiffe <holm at 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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