B. Format parameter page code =, FORMAT UNIT command

b.Format parameter (page code = 3)

Specify the number of spare sectors for each cylinder in the "alternate sectors/zone" field and specify the number of tracks for alternate cylinders (= number of alternate cylinders × number of disk drive heads) in the "alternate tracks/zone" field. It is recommended not to specify values smaller than the IDD default value in this field.

c.Drive parameter (page code = 4)

To explicitly specify the number of cylinders in the user space, specify the number in the "number of cylinders" field. Note that the number of alternate cylinders specified by the format parameter (page code = 3) is included in the number of cylinders in the user space. When the number of cylinders need not be specified, specify 0 or the default value in the "number of cylinders" field. In this case, either of the smaller value between the number of cylinders to allocate the number of logical data blocks specified in the "number of data blocks" field of the block descriptor or the maximum number of cylinders that can be used as the user space on the disk drive is allocated in the user space. When 0 is specified both in the "number of cylinders" field and the "number of data blocks" field of the block descriptor, the maximum number of cylinders that can be used as the user space on the disk drive is allocated in the user space.

(2)FORMAT UNIT command

Initialize all sides of the disk with the FORMAT UNIT command. The FORMAT UNIT command initializes all sides of the disk using the P lists, verifies data blocks after initialization, and allocates an alternate block for a defect block detected with verification. With initialization, the value "00" is written into all bytes of all logical data blocks. Only the position information of defect blocks detected with verification is registered in the G list. The specifications are as follows:

a.Specifying CDB

Specify 0 for the "FmtData" bit and the "CmpLst" bit on CDB, 000 for the "Defect List Format" field, and data pattern written into the data block at initialization for the "initializing data pattern" field.