Write And Verify (2Eh); Figure 171. Write And Verify - IBM IC35L036UWDY10 - Ultrastar 36.7 GB Hard Drive Specifications

8.42 WRITE AND VERIFY (2Eh)

Byte
7 6
0
1 Reserved = 0
2 (MSB)
3
4
5
6
7 (MSB
8
9 VU = 0

Figure 171. WRITE AND VERIFY

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.
! 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.
! 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.
! 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.
! Relative Block Address is not supported. Must be set to zero.
Bit
5 4 3
Command Code = 2Eh
Reserved
DPO
= 0
Logical Block Address
Reserved = 0
Transfer Length
Reserved = 0
Ultrastar 146Z10 hard disk drive specifications
2 1 0
Byte RelAdr
Chk = 0
(LSB)
(LSB)
FLAG LINK
168