Fujitsu MAN3735 Manuale Utente

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C141-E124-01EN
5 - 27
5.3.3
Error recovery processing control
The INIT can, by specifying the MODE SELECT parameters, can control the error recovery
processing (retries) of the IDD with respect to each type of error related to the disk drive.
Table 5.5  shows the types of error and the method of specifying the number of retries for those
errors.  for those items where the INIT can specify the number of retries, normally, it is
recommended that the default value or a greater number of times be specified.  If a value smaller
than the default value is specified, and commands are terminated abnormally without error
recovery processing succeeding, the INIT should reset the corresponding MODE SELECT
parameters at the default value, then reexecute the original commands.
The MODE SELECT parameters related to disk drive error recovery processing which the INIT
can specify are shown below.  See the description of the MODE SELECT command (Section
3.1.5) concerning details of the functions of each parameter.  The INIT can issue the MODE
SELECT or MODE SELECT EXTENDED command as necessary and select the error recovery
flags and the number of retries.
a.
Read/Write Error Recovery Parameters (Page Code = 1)
AWRE (automatic write reallocation enabled)
ARRE  (automatic read reallocation enabled)
TB (transfer block)
EER (enable early recovery)
PER (post error)
DTE (disable transfer on error)
DCR (disable correction)
Number of retries during read (See Table 5.5)
Number of retries during write (See Table 5.5)
b. Verify Error Recovery Parameters (Page Code = 7)
EER
(enable early recovery)
PER
(post error)
DTE
(disable transfer on error)
DCR
(disable correction)
Number of retries during verify (See Table 5.5)