smith@umn-cs.UUCP (Richard Smith) (11/29/83)
#R:sri-arpa:-1389400:umn-cs:6900021:000:1068 umn-cs!smith Nov 28 13:50:00 1983 Hard Sectored vs Soft Sectored Diskettes: The older Heathkit 5.25" systems use hard sectored diskettes; most popular systems these days use soft sectored diskettes. The major difference is that hard sectored diskettes have physical holes in the disk itself that the hardware can use to locate the approximate boundaries of sectors. Generally, a disk controller uses the 'formatting' data to find specific sectors on a track. The formatting data consists of a sector header containing the sector address and often the track number as well. This information is stored magnetically, of course, and thus must be written onto the diskette via some kind of formatting program. This is true for both hard and soft sectored diskettes. Owners of the old Heathkit drives have to run a formatting program on every diskette before being used in the drive. The Heathkit controller uses a combination of sector hole detection and sector header data checking to reliably locate a given sector on the diskette. Rick. [smith.umn-cs@CSNet-Relay] [...ihnp4!umn-cs!smith]