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Steen Jensen skrev:
Jim Oksvold skrev:Den er påtrykt: "TDK Life on Record 8GB" men isat en PC (både windows og minMandriva Linux) viser den kun 8MB som devicets samlede størrelse.Hvilken Windows og hvilken Linux kjerne? Er det stoette for mere enn 4GB? Mvh Jim OksvoldFundet på nettet:FAT12: The oldest type of FAT uses a 12-bit binary number to hold the cluster number. A volume formatted using FAT12 can hold a maximum of 4,086 clusters, which is 2^12 minus a few values (to allow for reserved values to be used in the FAT). FAT12 is therefore most suitable for very small volumes, and is used on floppy disks and hard disk partitions smaller than about 16 MB (the latter being rare today.)
Wikipedia siger følgende: FAT12The initial version of FAT is now referred to as FAT12. Designed as a file system for floppy diskettes, it limited cluster addresses to 12-bit values, which not only limited the cluster count to 4078,[7] but made FAT manipulation tricky with the PC's 8-bit and 16-bit registers. (Under Linux, FAT12 is limited to 4084 clusters.[8]) The disk's size is stored as a 16-bit count of sectors, which limited the size to 32 MB[9]. FAT12 was used by several manufacturers with different physical formats, but a typical floppy diskette at the time was 5.25-inch, single-sided, 40 tracks, with 8 sectors per track, resulting in a capacity of 160 KB for both the system areas and files. The FAT12 limitations exceeded this capacity by a factor of ten or more.
By convention, all the control structures were organized to fit inside the first track, thus avoiding head movement during read and write operations, although this varied depending on the manufacturer and physical format of the disk. At the time FAT12 was introduced, DOS did not support hierarchical directories, and the maximum number of files was typically limited to a few dozen. Hierarchical directories were introduced in MS-DOS version 2.0.[10]
A limitation which was not addressed until much later was that any bad sector in the control structures area, track 0, could prevent the diskette from being usable. The DOS formatting tool rejected such diskettes completely. Bad sectors were allowed only in the file area, where they made the entire holding cluster unusable as well. FAT12 remains in use on all common floppy disks, including 1.44MB ones.
men det er da meget enkelt at henvende sig i den pågældende forretning og få den byttet, hvis ikke der er 8 GB på. Det plejer ikke at være noget problem i Dansk Supermarkeds forretninger.
-- Med venlig hilsen Steen Jensen * Registered Linux user #172489 on http://counter.li.org.* INTET er umuligt for den, der ikke selv skal gøre det!
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