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

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SCSI Description
Quantum Atlas 10K II Ultra160/m SCSI Hard Disk Drives 5–213
5.45 VERIFY Command (2Fh)
The VERIFY command verifies the data on the medium for the Logical Block
Address range specified.
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (2Fh)
1 Reserved DPO Reserved BytChk RelAdr
2 - 5 Logical Block Address
6 Reserved
7 - 8 Verification Length
9 Control
Figure 5–105 VERIFY Command Descriptor Block — Data Format
Table 5–99 VERIFY Command — Field Descriptions
Field Description
DPO Disable Page Out. When the value of the field = 1, the device server shall
assign the logical blocks accessed by this command the lowest priority for
being fetched into or retained by the cache.
When DPO = 0, the priority shall be determined by fields in the Caching
page.
BytChk Byte Check. When the value is 1, the drive performs a byte-by-byte
comparison of the data on the medium with the data sent by the initiator
in the data-out buffer transfer.
When 0, the drive performs a medium verification with no data
comparison. In this case, no data is sent by the initiator.
RelAdr Relative Address. This feature is not supported; the field must be 0.
Logical Block Address The address of the first logical sector to be verified.
Verification Length The number of contiguous sectors that are to be verified. The drive returns
a CHECK CONDITION status with the correct sense data if the specified
transfer extends beyond out of the logical sector space.