Hitachi HUS154530VLF400 User Manual

                   

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

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The Verify recovery parameters are used by the Target when recovering from and reporting errors associated with the verifica-
tion of the Initiator's Data for the following commands:

• VERIFY

• WRITE AND VERIFY - the verify portion of the command only.

• EER.  This bit is 0 since the Target does not support early recovery.

• PER.  See below for description of bit values.

• DTE.  (Data Terminate on Error) bit set to one specifies that data transfer will be halted when the first recovered error is 

encountered.  PER must be set to one when DTE is set to one.  DTE set to zero will cause data transfer to continue 
when recovered errors are encountered.  

• DCR.  See below for description of bit values.

The PER, DTE, and DCR bit settings in mode page 7 override those of mode page 1 during VERIFY and the Verify portion of 
WRITE AND VERIFY.  The following combinations of PER and DCR are valid:
PER    DCR DESCRIPTION

Soft errors are not reported. ECC is applied to recover the data.

Soft errors are reported. ECC is applied to recover the data.

Soft errors are not reported. ECC is not used to recover the data.

Soft errors are reported. ECC is not used to recover the data.

• Verify Retry Count sets a limit on the amount of verify recovery procedure (VRP) passes the Target attempts when 

recovering verify errors. The Verify Retry Count of one causes the Target to attempt up to one VRP pass per com-
mand when a medium error occurs during a verify operation. Only values of 0h and 01h are valid. The value of 0h 
disables all recovery.

• Verify Recovery Time Limit indicates the period in 1 millisecond increments for the maximum recovery time of a sin-

gle LBA during the verify operation.  The value must be from 40 ms to 65535 ms (65.5 seconds).  The granularity of 
the timer is 50 ms.  If an LBA is not able to be recovered within the limit, a Check Condition will be returned.