Write And Verify Command - Seagate ST11200 Product Manual

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5.2.2.5 Write and Verify Command (2Eh)
Bit 7
Byte(s)
0 0
1 Logical Unit No.[1]
0
2
3
4
5
6 0
7
8
9 0
The WRITE AND VERIFY 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 transfered once from the initiator to
the drive.
Notes.
[1] The LUN must be zero.
[2] A disable page out (DPO) bit of one indicates that the target shall assign the logical blocks accessed by
this command the lowest priority for being fetched into or retained by the cache.
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. If the DPO bit is set to one, 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. If the DPO bit is zero, that logical blocks accessed
by this command are likely to be accessed again in the near future.
[3] A byte check (BytChk) bit of zero causes the verification to be simply a medium verification (ECC) with
no data comparison. A BytChk bit of one causes 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 shall be
terminated with a CHECK CONDITION status and the sense key shall be set to MISCOMPARE.
[4] RelAdr. See Description of RelAdr bit for the Write Extended Command.
[5] The logical block address specifies the logical block at which the write operation shall begin if RelAdr bit
is zero. (see description of RelAdr bit for the Write Extended Command).
[6] The transfer length specifies the number of contiguous logical blocks of data that shall be transferred. A
transfer length of zero indicates that no logical blocks shall be transferred. This condition shall not be
considered as an error and no data shall be written. Any other value indicates the number of logical
blocks that shall be transferred.
For Systems that support disconnection, the disc drive disconnects during the execution of this com-
mand.
[7] See "Control Byte" paragraph 4.2.6.
Product Manual - Disc Drive SCSI-2/SCSI-3 Interface (Vol. 2; Ver. 2), Rev. E
Table 5.2.2-5b. Write and Verify Command
6 5
0 1
0 0
0 0
0 0
4 3
0 1
DPO
0 [2] 0
Logical Block Address (MSB)
Logical Block Address
Logical Block Address
Logical Block Address (LSB)
0 0
Transfer Length (MSB)
Transfer Length (LSB)
0 0
2 1
1 1
BYT RelAdr
0 CHK [3]
0 0
0 Flag Link [7]
0
0
[4]
[5]
0
[6]