IBM Ultrastar 36LZX, Технические характеристики

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8.41 WRITE AND VERIFY (2E)
LINK FLAG Reserved = 0 VU = 0 9
(MSB Transfer Length
(LSB)
7
8
Reserved = 0 6
(MSB)
Logical Block Address
(LSB)
2
3
4
5
RelAdr
= 0
Byte
Chk
Reserved
= 0
DPO Reserved = 0 1
Command Code = 2Eh 0
0 1 2 3 4 5 6 7
Bit
Byte
Figure 159. WRITE AND VERIFY (2E)
WRITE AND VERIFY command requests that the drive writes the data transferred from the initiator to
the medium and then verify that the data is correctly written.
Ÿ
Transfer Length of zero indicates that no data is transferred.
If caching is enabled, the command performs an implied Force Unit Access (FUA) and an implied
Synchronize Cache before starting the operation. This insures that the medium, not the cache, is
being verified.
Ÿ
ByteChk bit set to zero indicates that the data is read back from the disk and verified using ECC
after the successful write operation. If an ECC error is detected in the verify process, CHECK
CONDITION status is returned with sense key set to MEDIUM ERROR. ByteChk bit set to one
indicates that byte-by-byte comparison is performed between data on the disk starting the block
specified in LBA field and data transferred from the initiator.
If the comparison is unsuccessful, the command is terminated with CHECK CONDITION status and
the sense key is set to MISCOMPARE.
Ÿ
DPO (Disable Page Out) bit of one indicates that the data written by this command is to be assigned
the lowest priority for being written into or retained by the cache. A DPO bit of one overrides any re-
tention priority specified in the Mode Select Page 8 Caching parameters. A DPO bit of zero indicates
the priority is determined by the retention priority.
The initiator should set the DPO bit when the blocks written by this command are not likely to be
read again in the near future.
Ÿ
Relative Block Address is not supported. Must be set to zero.
Ultrastar 36LZX hard disk drive specifications
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