Seagate ST3285N, Product Manual

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3.5.6 Verify command (2F
H
)
When the drive receives the Verify command, it verifies the data on the
disc. If the host adapter supports disconnection, the drive disconnects
while it is executing this command.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 1 0 1 1 1 1
1 LUN 0 0 0
BYT
CHK
REL
ADR
2–5 Logical block address
6 0 0 0 0 0 0 0 0
7–8 Verification Length
9 0 0 0 0 0 0 Flag Link
Byte 1 If the BYT CHK (byte check) bit is zero, the drive verifies
the media without performing a byte-by-byte comparison of
the stored data. If the BYT CHK bit is one, the drive verifies
the media and performs a byte-by-byte comparison of the
stored data.
A REL ADR bit of zero means that the logical block address
field specifies the first logical block of the range of logical
blocks to be written by the drive. If the REL ADR bit is one,
the logical block address field is a two’s complement dis-
placement. This displacement is added to the logical block
address last accessed on the drive to determine the logical
block address for this command. The REL ADR bit should
only be one if linked commands are used.
Bytes 2–5 The
logical block address field specifies the logical block
where the drive begins verifying the data.
Bytes 7–8 The
verification length field specifies the number of contigu-
ous logical blocks to be verified. If the verification length is
zero, the drive does not verify any logical blocks although
an implied seek is still performed. This condition is not
considered an error.
ST3655 Family SCSI Drives Product Manual, Rev. A 67