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 76543210
010101110
1000000
BytChk RelAdr
Reserved DPO
2Logical Block Address (MSB)
3Logical Block Address
4Logical Block Address
5Logical Block Address (LSB)
6Transfer Length (MSB)
7Transfer Length
8Transfer Length
9Transfer Length (LSB)
10 Reserved
11 Control
AEh
Table
number
225
225
225
225
225