IBM DDRS-39130 - Ultrastar 9.1 GB Hard Drive, Технические характеристики

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occurred, then normal D R P could result in considerable recovery action, including proceeding through
all levels of D R P .
R C set to 0 indicates normal interpretation of PER, DTE, DCR, and TB values. The R C bit setting is
used by the Target when reporting errors associated with the transfer of the Initiator's data for the fol-
lowing commands:
−
Read(6)
−
Read(10)
For all other commands, the R C bit setting is unused and treated as 0.
EER,An enable early recovery bit. Must be set to zero , indicating that the file shall use an error
recovery procedure that minimizes the risk of mis-detection or mis-correction during the data transfer.
Data shall not be fabricated.
PER, Post Error bit, is set to one to indicate that the file reports recovered errors.
DTE, Disable Transfer on Error bit, is set to one to indicate that the file terminates the DATA phase
upon detection of a recovered error .
DCR, Disable Correction bit, is set to one to indicate that Error Correction Code is not used for data
error recovery.
A D C R bit of zero indicates that ECC is applied to recover the data.
Read Retry Count sets a limit on the amount of D R P passes that the Target attempts to recover read
errors. A value of zero disables all data recovery procedures always. When AVERP bit (Mode Page 0
Byte 6 Bit 6) is zero, a value of non-zero in Read Retry Count enables all steps of D R P . When
AVERP bit is one, the number in Read Retry Count sets the maximum retry count of D R P .
Correction Span field specifies the size, in bits, of the largest data error burst for which data error cor-
rection may be attempted. Any value may be set into this field, including zero. The file will always use
it's default correction capabilities.
Head Offset Count is not supported by the file.
Note: Head Offset is implemented in the read error recovery routine. The user can not modify the
offset value.
Write Retry Count sets a limit on the amount of D R P passes that the Target attempts to recover write
errors. A value of zero disables all data recovery procedures always. When AVERP bit (Mode Page 0
Byte 6 Bit 6) is zero, a value of non-zero in Write Retry Count enables all steps of D R P . When
AVERP bit is one, the number in Write Retry Count sets the maximum retry count of D R P .
Recovery Time Limit will be ignored when AVERP bit (Mode Page 0 Byte 6 Bit 6) is zero. When
AVERP bit is set to 1, Recovery Time Limit sets the maximum command execution time with incre-
ment factor of 1 msec. If a command is not able to be completed within the limit, a check condition
will be returned. The Recovery Time Limit should be between 40 msec and 1600 msec, or this function
is ignored.
SCSI C O M M A N D SET
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