Following are the parameters stored in a PC's BIOS setup memory that describe the configuration of the hard disks in the system. SCSI hard disks are usually not identified in the setup memory.
Hard Disk Types
There are 46 hard disk types, numbered 1 to 46, that include all the required parameters below. Since they cover earlier drives that only go up to 152MB, the user-configurable Type 47 is usually chosen and the remaining parameters are entered manually or are automatically detected (all new drives are detected).
CYLINDERS Number of cylinders.
HEADS Number of read/write heads.
WPCOM Write precompensation track.
LANDING
ZONE Cylinder for parking heads.
SECTORS Sectors per track.
CAPACITY Total capacity derived from
above parameters (heads X
cylinders X sectors X 512)