Verify (12) Command - Seagate 77767496 Product Manual

12.55

Verify (12) command

The Verify (12) command requests that the target verify the data written on the medium. This command is
implemented with the disc drive specific parameters listed in Table 218. The drive disconnects while this com-
mand is being executed if the initiator supports disconnect/reconnect.
Table 218: Verify (12) command (AFh)
Bit 7
Byte
0 1
1 0
Logical Block Address (MSB)
2
Logical Block Address
3
Logical Block Address
4
Logical Block Address (LSB)
5
Verification Length (MSB)
6
Verification Length
7
Verification Length
8
Verification Length (LSB)
9
Reserved
10
Control
11
Field definitions (listed alphabetically)
Table
number
BytChk (Byte Check)
218
0 The verification will be a medium verification (CRC, ECC, etc.).
1 A byte-by-byte compare of data on the medium and the data transferred from the initiator. If the compare is unsuc-
cessful, the command terminates with a Check Condition status and the sense key is set to Miscompare.
Control
218
See Control Bytes in Section 11.2.1.6.
DPO (Disable Page Out)
218
The DPO bit is used to control replacement of logical blocks in the cache memory when the host has information on the
future usage of the logical blocks.
1 The target assigns the logical blocks accessed by this command the lowest priority for being fetched into or retained
by the cache. The logical blocks accessed by the command are not likely to be accessed again in the near future
and should not be put in the cache memory nor retained by the cache memory.
0 Logical blocks accessed by this command are likely to be accessed again in the near future.
Logical Block Address
218
The logical block at which the verify operation begins, if RelAdr is zero (0).
RelAdr (Relative Address)
218
This function is not supported by drives described in this manual.
318
AFh
6 5
0 1
0 0
Reserved
4 3
0 1
0 0
DPO
Fibre Channel Interface Manual, Rev. D
2 1
1 1
0
BytChk RelAdr
0
1