4 format unit initialization pattern descriptor – Quantum 10K II User Manual

Page 97

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SCSI Description

5–30

Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives

FORMAT UNIT Command (04h) (continued)

5.10.2.3 FORMAT UNIT Defect Descriptor — Physical Sector and Bytes From

Index Format

The Physical Sector defect descriptor specifies the location of a defect that is the
length of a sector. The Bytes From Index defect descriptor specifies the location of a
defect that is no more than eight bytes long.
Each descriptor is comprised of the bytes shown in Figure 5-8. The Cylinder Number
of Defect is the most significant part of the address, and the Defective Sector
Number or Defect Bytes From Index is the least significant part of the address. A
value of FFFFFFFFh in bytes 4 to 7 is ignored.

Bit

Byte

7

6

5

4

3

2

1

0

0 - 2

Cylinder Number of Defect

3

Head Number of Defect

4 - 7

Defective Sector Number

or

Defect Bytes from Index

Figure 5–8 FORMAT UNIT Defect Descriptor — Physical Sector and Bytes

From Index Format

5.10.2.4 FORMAT UNIT Initialization Pattern Descriptor

The Initialization Pattern option specifies that the logical blocks on the drive
medium shall contain a specified initialization pattern. The Initialization Pattern
descriptor is sent to the drive as part of the FORMAT UNIT parameter list. The
contents of the descriptor fields are described in Table 5-10.

Bit

Byte

7

6

5

4

3

2

1

0

0

IP Modifier = 0

Reserved

1

IP Type

2 - 3

IP Length

4 - n

IP

Figure 5–9 FORMAT UNIT Initialization Pattern Descriptor — Data Format

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