Re: [PATCH] zip drives

From: Manfred Spraul (
Date: Wed Mar 15 2000 - 15:25:34 EST

From: "James Sutherland" <>
> > Gadi Oxman writes:
> >
> > > Another point to add is that some (newer?) ZIP drives have a jumper
> > > on them which enables some cheat mode for MSDOS which actually hides
> > > some sectors from the device driver.

Both WinNT and Windows 95 need the cheat mode: IIRC they don't analyze the
partition table if the device reports itself as ATAPI FLOPPY.

> > > That is, block 0 on the drive
> > > actually moves along with the partition table, and perhaps also the
> > > reported capacity.
Fixed 32 blocks, they don't analyze the partition table.

> [...]
> Load first sector. Is it an MBR/partition table, or a boot sector?
> If the former, add an offset of 32 sectors to all subsequent accesses.
> This way, we get consistent behaviour from both types of drive.
> You then always mount /dev/sda (or whatever).

What if you have a partition table with != 32 sectors? Just try to mount an
hfs formatted disk, the lenght of the partition table depends on the version
of the formatter :-(

But it possible to disable this mode with some special ATAPI commands, IIRC
my brother told me that he send them to a linux developer a few months ago.


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