PC-DOS 720K format - Revision history

Jsummers: Category:MS-DOS

2017-03-29T16:30:47Z

Category:MS-DOS

Dan Tobias at 02:30, 22 April 2014

2014-04-22T02:30:09Z

Dan Tobias at 02:29, 22 April 2014

2014-04-22T02:29:18Z

Dan Tobias at 19:20, 9 May 2013

2013-05-09T19:20:33Z

Dan Tobias at 17:23, 7 May 2013

2013-05-07T17:23:32Z

Dan Tobias at 12:46, 7 May 2013

2013-05-07T12:46:44Z

Dan Tobias at 03:36, 7 May 2013

2013-05-07T03:36:43Z

Dan Tobias: Created page with "{{FormatInfo |formattype=physical |subcat=Floppy disk }} The '''PC-DOS 720K format''' (3 1/2", double sided, double density) was a very common floppy disk format in the late ..."

2013-05-07T03:32:06Z

Created page with "{{FormatInfo |formattype=physical |subcat=Floppy disk }} The '''PC-DOS 720K format''' (3 1/2", double sided, double density) was a very common floppy disk format in the late ..."

New page

{{FormatInfo
|formattype=physical
|subcat=Floppy disk
}}

The '''PC-DOS 720K format''' (3 1/2", double sided, double density) was a very common floppy disk format in the late 1980s and into the 1990s, used on IBM PCs and compatibles. It was the main 3 1/2" disk format for the PC platform until the high-density [[PC-DOS 1.44MB format]] was introduced. It had 80 tracks per side, with 9 sectors per track, and 512 bytes per sector. Data was stored with [[MFM encoding]]. The disk turned at 300 RPM.

These disks were generally used with [[FAT12]] file systems under the MS-DOS or PC-DOS operating system. The disks held exactly twice as much data as the earlier 5 1/4" [[PC-DOS 360K format]], even though the disks were smaller.

The [[PC-DOS 1.44M format]] later took over much floppy-disk usage, though the lower-density 720K disks remained in use as well, with the high-density drives supporting both formats (though there could be compatibility issues in reading 720K disks on low-density drives after they were written to with a high-density drive, even though the writing is done in an emulation of the old format, due to the different drive head on the newer drives).

[[Category:IBM]]
[[Category:Microsoft]]

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 |subcat=Floppy disk
 }}
 The '''PC-DOS 720K format''' (3 1/2", double sided, double density) was a very common floppy disk format in the late 1980s and into the 1990s, used on IBM PCs and compatibles. It was the main 3 1/2" disk format for the PC platform until the high-density [[PC-DOS 1.44M format]] was introduced. It had 80 tracks per side, with 9 sectors per track, and 512 bytes per sector. Data was stored with [[MFM encoding]]. The disk turned at 300 RPM.

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 These disks were generally used with [[FAT12]] file systems under the MS-DOS or PC-DOS operating system. The disks held exactly twice as much data as the earlier 5 1/4" [[PC-DOS 360K format]], even though the disks were smaller.
-The [[PC-DOS 1.44M format]] later took over much floppy-disk usage, though the lower-density 720K disks remained in use as well, with the high-density drives supporting both formats (though there could be compatibility issues in reading 720K disks on low-density drives after they were written to with a high-density drive, even though the writing is done in an emulation of the old format, due to the different drive head on the newer drives).
+The [[PC-DOS 1.44M format]] later took over much floppy-disk usage, though the lower-density 720K disks remained in use as well, with the high-density drives supporting both formats (though there could be compatibility issues in reading 720K disks on low-density drives after they were written to with a high-density drive, even though the writing is done in an emulation of the old format, due to the different drive head on the newer drives; this sort of incompatibility might, however, not have been as common as that between the high and low density 5 1/4" disks).
 In the late '80s and early '90s, it was common for desktop PCs to have both 5 1/4" and 3 1/2" disk drives in order to be compatible with all software and data, which might be distributed on either format. Often the 5 1/4" drive was drive A, and the 3 1/2" one was drive B. Later PCs, however, were more likely to have only a 3 1/2" drive, set up to respond to both drive letters. Eventually, PCs stopped having floppy disk drives altogether as other data storage and transfer media took over.

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 1/2" disks are actually 90 mm wide, but are almost universally referred to as "3 1/2 inch" disks even in countries that use the metric system.
 [[Category:IBM]]
 [[Category:Microsoft]]