FIXED DISK CONTROLLERS— Fixed disk
controllers control the disk drive. The controller can
determine what encoding method is used, what the
interleave factor of the disk is, and what interface is used
to communicate with the host computer. It is very
important that the disk drive and controller are
compatible with each other. Some disk controllers are
located on the drive logic boards, while other disk
controllers are on a separate circuit board with the
interface.
FIXED DISK INTERLEAVE FACTOR—
Interleaving is a method for logically numbering sectors
to allow time for the controller to process data. The
fastest drive/controller combinations can support a 1:1
interleave.
FIXED DISK INTERFACES— Fixed disk
interfaces determine how the disk controller
communicates with the host computer. In some cases
the disk controller is on the same circuit board as the
interface. The most common interfaces in use are the
ST-506/412, the Integrated Drive Electronics (IDE)
Interface, the Enhanced Small Device Interface (ESDI),
and the Small Computer Systems Interface (SCSI).
FORMATTING FIXED DISKS— Before a fixed
disk can be used in a personal computer, it must be
formatted. Total formatting consists of a low-level
format, making a disk partition, and a high-level format.
RECOVERING DATA FROM FIXED DISK
DRIVES— Most of the time data can be recovered from
a fixed disk. Accidentally erased files can be recovered.
If your computer is infected by a virus, it is sometimes
possible to recover files and get rid of the virus. Broken
drives can be revived long enough to get important files
off them. The best protection from data loss is regular
and complete backups of your data files.
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