http://fileformats.archiveteam.org/index.php?action=history&feed=atom&title=RockFAT 2026-04-21T14:04:34Z Revision history for this page on the wiki MediaWiki 1.19.2 http://fileformats.archiveteam.org/index.php?title=RockFAT&diff=46159&oldid=prev 2023-11-04T19:09:33Z

<p>Created page with &quot;{{FormatInfo |subcat=Error detection and correction |released=2000 }} &#039;&#039;&#039;RockFAT&#039;&#039;&#039; (&#039;Rock-solid diskettes with error correcting codes&#039;) by Thanassis Tsiodras stores a file w...&quot;</p> <p><b>New page</b></p><div>{{FormatInfo<br /> |subcat=Error detection and correction<br /> |released=2000<br /> }}<br /> <br /> '''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<br /> <br /> <br /> The Linux version creates a floppy image that can be written with dd while the Windows version writes directly to the floppy<br /> <br /> It only supports a single file with a filename of less than 16 chars.<br /> <br /> Each block contains 232 bytes of data + 24 bytes of parity, allowing the recovery of 12 bytes of data per block<br /> <br /> Then the data is interleaved such that<br /> <br /> {| class=&quot;wikitable&quot;<br /> |-<br /> | 1st byte of stream || first byte of first sector<br /> |-<br /> | 2nd byte of stream || first byte of Nth sector<br /> |-<br /> | ... || ...<br /> |-<br /> | (2880/N) byte of stream || first byte of second sector<br /> |-<br /> | ((2880/N)+1) byte of stream || first byte of (2+N)th sector<br /> |-<br /> | ... || ...<br /> |}<br /> <br /> (N=8 for this implementation)<br /> <br /> Thus in the worst case, it can recover from 11 bad sectors and possibly more depending on how the damage is spread out<br /> <br /> 2880 sectors X 512 bytes X (232/256) = 1336320 bytes available - 4-byte stream length - 16-byte filename = 1336300 bytes per floppy<br /> <br /> <br /> == Links ==<br /> * [https://www.thanassis.space/RockFAT.html Homepage]<br /> * [https://web.archive.org/web/20020107050802/http://www.softlab.ntua.gr:80/~ttsiod/RockFAT.html Older homepage (archived)]</div>

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