Quantum Quantum Atlas 10K II 9.2/18.4/36.7/73.4 GB, Product Manual

Page: 214 / 371

SCSI Description
Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives 5–147
5.25 READ DEFECT DATA Command (12) (B7h)
The READ DEFECT DATA (12) command directs the drive to report defect
information about the drive’s medium. Refer to the FORMAT UNIT command for
information about defects. The data sent to the host in the command’s data-in buffer
transfer consists of a four-byte Defect List header (Figure 5-68), followed by any
Defect Descriptors (Figures 5-66 and 5-67).
The READ DEFECT DATA (12) Command Descriptor Block is shown in Figure 5-
65; the data fields are described in Table 5-69.
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (B7h)
1 Reserved Plist Glist Defect List Format
2 - 5 Reserved
6 - 9
(MSB)
Allocation Length
(LSB)
10 Reserved
11 Control
Figure 5–65 READ DEFECT DATA (12) Command — Data Format
Table 5–69 READ DEFECT DATA (12) Command — Field Description
Field Description
PList When the value is 0, the returned data does not include the Primary Defect
List.
When the value is 1, the returned data includes the Primary Defect List. The
defects are returned in ascending order.
GList When the value is 0, the returned data does not include the Grown Defect
List.
When the value is 1, the returned data includes the Grown Defect List. The
defects are returned in order of occurance.
When both PList and GList are set to 1, the Primary Defect List and the
Grown Defect List are returned. The Plist is returned followed by the Glist
(the lists are not merged). When both are set to 0, only the Defect List
Header (Figure 5-68) is reported to the initiator.
( continued )