Saturday, September 28, 2019
FAT file systems Essay Example | Topics and Well Written Essays - 1000 words
FAT file systems - Essay Example File Allocation Tables (FAT) is of huge significance to the users of Compact Flash (CF) because the requirement of FAT type is different for the devices that are optimized with over 2.14 gigabytes (GB) of storage capacity unlike those that require only 2.13 GB. This topic has gained huge importance specifically after the hard diskââ¬â¢s application into the personal computers. This paper tends to create awareness among the camera users regarding the FAT through a comprehensive discussion of its history. Introduction: The subject of this white paper is the illustration of FAT File Systems. This white paper is directed at creating an understating among the users of camera regarding the File Allocation Tables, which are generally referred to as FAT. Because of the disparity between the need of FAT type among different devices, Compact Flash (CF) users need to be given a thorough understanding of the FAT so that they may be able to make the right choice as per their device. The scope of this white paper is limited to the discussion of history of FAT File Systems along with a brief review of the relation of FAT with the Compact Flash (CF) devices which generate files with sizes up to 5+ mega pixels. This white paper first gives a comprehensive account of the historical background of FAT. This is followed by a review of the use of FAT File Systems in CF. Finally, the findings are concluded in the last section. History of FAT File System: Development of FAT File System: In February, 1976, during his stay at the Albuquerqueââ¬â¢s Hilton Hotel spanning five days, a child known as Bill Gates who has gained immense fame for his contributions in the world of computer developed and coded FAT (Gilbert). ââ¬Å"FAT was designed for small disks and simple folder structuresâ⬠(Microsoft). Replacement of floppy disks with double-sided diskettes: The original Personal Computers made use of floppy disks for carrying the data whose capacity usually used to be 180 kilobyt es. After the floppy disks, use of double-sided diskettes increased. The double-sided diskettes used to be double the capacity of the floppy disks and were up to 5 ? inches in size. The initial DOS developers indicated the relation of sectors to individual files as well as identified the vacant tables by creating tables with a view to organizing the data. As a result of this, the Operating System (DOS) was able to use the limited space on the double-sided diskettes to the maximum limit. There was no more the need of availability of a continuous series of sectors for saving the files. It was possible to break up the data for the files and distribute that everywhere in the double-sided diskette in an increasingly organized and sequenced fashion; a process that is frequently referred to as fragmentation. Nevertheless, it was fortunate in those times to be able to keep the data in one diskette because one would not need to switch the diskettes in and out alternately time and again while the programââ¬â¢s operation would continue. Selection of table length: There are 768 sectors upon a diskette with a capacity of 360 KB. This required the table to be large enough in order to determine every single sector of the total of 768. There was also the requirement of some room for expansion because the developers were aware of the on-going creation of larger diskettes. Number of possible values permitted by the use of one byte per table did not exceed 512, so that would not practically serve the purpose. On the other hand, two bytes would waste the disk space by permitting 16384 entries. Thus, decision had to be made somewhere in between one and two bytes. So finally, table with the length of 12 bits that were equal to 1.5 bytes were chosen so that the usage of sectors on the first double-sided diskettes could be traced. As a result of this, 4096 possible values were permitted. Such a FAT table was able to deal with storage devices with the capacity as large as 2 GB prov ided that each entry
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