62 write and verify (12) command, Write and verify (12) command – Seagate Fibre Channel Interface User Manual
Page 345
Fibre Channel Interface Manual, Rev. D
331
12.62
Write and Verify (12) command
The Write and Verify (12) command requests that the target write the data transferred from the initiator to the
medium and then verify that the data is correctly written. The data is only transferred once from the initiator to
the drive.
Field definitions (listed alphabetically)
BytChk (Byte Check)
0
Verification will be a medium verification (ECC) with no data comparison.
1
A byte-by-byte compare of data written on the peripheral device and the data transferred from the initiator. If the
compare is unsuccessful, the command terminates with a Check Condition status and the sense key is set to Mis-
compare.
Control
See Control Bytes in Section 11.2.1.6.
DPO (Disable Page Out)
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
The logical blocks accessed by this command are likely to be accessed again in the near future.
Logical Block Address
The logical block at which the write operation begins if RelAdr bit is zero (see RelAdr bit definition).
RelAdr (Relative Address)
This function is not supported by drives described in this manual.
Table 225: Write and Verify (12) command (AEh)
Bit
Byte
7
6
5
4
3
2
1
0
0
1
0
1
0
1
1
1
0
1
0
0
0
0
0
0
BytChk
RelAdr
Reserved
DPO
2
Logical Block Address (MSB)
3
Logical Block Address
4
Logical Block Address
5
Logical Block Address (LSB)
6
Transfer Length (MSB)
7
Transfer Length
8
Transfer Length
9
Transfer Length (LSB)
10
Reserved
11
Control
AEh
Table
number