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FutureOS

116 bytes added, 23:48, 8 January 2010
/* File system */
Filenames can use all 256 different characters and user areas from 0 to 254 (except for &E5, which is reserved for deleted files). Unlike Amsdos, a file that is erased under FutureOS is not shifted to user &E5, but is physically removed from the directory. File headers are displayed as AmsDOS files or the icon-like file-header of a FutureOS program. An AmsDOS file header has 128 bytes of which are unused. FutureOS makes use of those unused bytes so that files have a length definition of 24 bit (16 MB file length) and can have a physical RAM select. Therefore a file can be defined to be loaded everywhere in the external RAM. Also a FutureOS file-header can contain a graphical icon, a textual icon or a short description of the file.
FutureOS includes the fastest FDC-based disc- and file-reading and writing routines for the CPC. This is possible by ignoring the interleave factor, reading one physical sector directly after each other to the correct position in memory but also by just starting with the first appearing sector of every new track. In addition the DIRectory is buffered in RAM, the head of the floppy must not step back to look for the next block. With an increased track step rate it's even faster than optimized copy programs like Crowns' [[Crime|Crime]].
== Implementation of Hardware ==
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