IBM Ultrastar 36LZX, Технические характеристики

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11.7 Write Cache
If the WCE (Write cache enable) bit is 1, the drive returns Good Status and Command Complete
message and goes to Bus Free immediately after receiving the data of the last sector before actually
writing the data onto the media.
If the drive detects an error after it returns a Good Status, the drive sets a Deferred Error (Error Code of
sense data = 71h) and a following command will be returned with Check Condition and the Contingent
allegiance condition is established. Under the Contingent allegiance condition all queued processes
including commands from other initiators are suspended.
11.8 Automatic Rewrite/Reallocate
The target supports Auto and Recommended Reallocate for READ, WRITE, WRITE VERIFY, and
VERIFY.
Automatic and Recommend Reallocate operate from within the read/write command. When an automatic
reallocation occurs, the read or write command takes longer to complete.
This operation is sometimes referred to as auto-reassignment due to its similarity to the operation per-
formed by the reassign command.
Following is a description of the target behavior for each setting of ARRE. ARRE setting affects all data
errors. (No Sector Found, Data Sync Byte Errors and Data ECC Errors.)
ARRE=1: An error site determined to need rewriting or reallocation during a read is automatically
rewritten or reallocated at the conclusion of the read and prior to the sending of the
status. The site will be automatically rewritten or reallocated only if the data has been
successfully read.
ARRE=0: An error site determined to need rewriting or reassignment during a read is recom-
mended for rewriting or reassignment at the conclusion of the read.
The setting of the ARRE bit is checked and the target will automatically rewrite/reallocate or recommend
rewrite/reassign for the following commands.
Ÿ
Read(6)
Ÿ
Read(10)
Ÿ
Verify
Ÿ
Verify Portion of Write and Verify
For all other commands the ARRE setting is ignored and the target will not automatically rewrite/
reallocate or recommend rewrite/reassign.
Following is a description of the target behavior for each setting of AWRE. AWRE setting effects only No
Sector Found Errors on writes.
AWRE=1 : An error site determined to need reassignment during a write is automatically reallocated
at the conclusion of the write and prior to sending the status. The site will be auto-
matically reallocated only if the write recovery succeeded at the conclusion of the write.
AWRE=0 : An error site determined to need reassignment during a write is recommended for
reassignment at the conclusion of the write.
The setting of the AWRE bit is checked and the target will automatically reallocate or recommend
reassign for the following commands.
Ÿ
Write(6)
Ultrastar 36LZX hard disk drive specifications
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