HP 2600fx - Optical Disk Drive Command Reference Manual page 178

DPO A Disable Page Out bit of 1 instructs the target not to
retain the data in the cache after it has been verified.
A DPO bit of 0 instructs the target to retain the data in
the cache after it has been verified.
This bit is ignored.
Blk Vfy A Blank Verify bit of 1 indicates the drive verifies that
sectors are erased.
A Blk Vfy bit of 0 indicates the drive verifies written
data integrity.
Rel Adr A relative address bit of one indicates that logical block
address specified is a two's complement offset from the
last logical block address accessed.
A value of 0 indicates that the logical block address is an
absolute address.
Verification
Length Specifies the number of contiguous logical blocks of data
to be verified. A value of 0 indicates that no blocks will
be verified and is not considered an error.
Chapter 2
SCSI-2 Drive Command Set
Verify (Group 5) Command (AFH)
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