mtools: more sectors
2.7.1 More sectors
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The oldest method of fitting more data on a disk is to use more sectors
and more cylinders. Although the standard format uses 80 cylinders and
18 sectors (on a 3 1/2 high density disk), it is possible to use up to
83 cylinders (on most drives) and up to 21 sectors. This method allows
to store up to 1743K on a 3 1/2 HD disk. However, 21 sector disks are
twice as slow as the standard 18 sector disks because the sectors are
packed so close together that we need to interleave them. This problem
doesn't exist for 20 sector formats.
These formats are supported by numerous DOS shareware utilities such
as 'fdformat' and 'vgacopy'. In his infinite hubris, Bill Gate$
believed that he invented this, and called it 'DMF disks', or 'Windows
formatted disks'. But in reality, it has already existed years before!
Mtools supports these formats on Linux, on SunOS and on the DELL Unix
PC.