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File Format
Name RockFAT
Released 2000

RockFAT ('Rock-solid diskettes with error correcting codes') by Thanassis Tsiodras stores a file with parity recovery data directly on a floppy with no filesystem in a way that maximizes the ability to recover from burst sector errors

The Linux version creates a floppy image that can be written with dd while the Windows version writes directly to the floppy

It only supports a single file with a filename of less than 16 chars.

Each block contains 232 bytes of data + 24 bytes of parity, allowing the recovery of 12 bytes of data per block

Then the data is interleaved such that

1st byte of stream first byte of first sector
2nd byte of stream first byte of Nth sector
... ...
(2880/N) byte of stream first byte of second sector
((2880/N)+1) byte of stream first byte of (2+N)th sector
... ...

(N=8 for this implementation)

Thus in the worst case, it can recover from 11 bad sectors and possibly more depending on how the damage is spread out

2880 sectors X 512 bytes X (232/256) = 1336320 bytes available - 4-byte stream length - 16-byte filename = 1336300 bytes per floppy


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