Hitachi HUS154530VLF400 Manual De Usuario

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification

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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. If caching is enabled, an implied FUA (Force Unit Access) and an implied Synchronize 
Cache are performed before starting the operation.  This insures that data from the disk, not the cache, is verified.

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See the WRITE (10) command description for the definition of the WRPROTECT field. 

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Transfer Length is the number of contiguous blocks to to transferred.  If the transfer length is zero, the seek occurs, 

but no data is transferred.  This condition is not considered an error.

If caching is enabled, the command performs an implied FUA and an implied Synchronize Cache before starting the 
operation. This insures that the medium, not the cache, is being verified.

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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.

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DPO (Disable Page Out) bit of one indicates that the data written by this command is to be assigned the lowest prior-

ity for being written into or retained by the cache. A DPO bit of one overrides any retention priority specified in the 
Mode Select Page 8 Caching parameters. A DPO bit of zero indicates the priority is determined by the retention pri-
ority.

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.