Optical Drive and Library SCSI-2 Command Reference
SCSI-2 Drive Command Set
Verify (Group 5) Command (AFH)
Chapter 2 2-141
SCSI-2 Drive Commands
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.










