Fujitsu MBC2073RC Manual Do Utilizador

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Sense Data and Error Recovery Methods 
 
386 
C141-C013 
If error recovery is completed by rewriting the data to the data block, alternate 
block allocation is not performed for this data block.  The data block is removed 
as the target of AWRE processing. 
(3)  Auto alternate block allocation processing during a write operation 2 (servo auto 
alternate)  
This function is enabled by specifying "1" in the AWRE flag in the MODE 
SELECT parameters. Furthermore, this function is applicable to the following 
commands only. 
• 
WRITE command 
• 
WRITE EXTENDED command 
• 
WRITE AND VERIFY command 
When this function is permitted, if, during WRITE/WRITE EXTENDED 
command detects any Servo error (e.g. Write offtrack error) and cannot be 
recovered within pre-determined retry number (specified in Mode Parameter).  
For the sectors around defective Servo, alternate blocks are allocated and the data 
of this WRITE commands are re-written. 
Sectors to be made AWRE shall be following: 
• 
the sector where the error occurs and the latter sectors and, 
• 
the sectors whose data are logically continual and stored in Cache, 
• 
the sectors which will be processed in this Write command and, 
• 
the sectors which locate between erroneous Servo -1 and +1 (including Split 
sector) 
This function is also applied for the sector which has already been re-assigned. 
6.3.3  Error recovery processing control 
The INIT can, by specifying the MODE SELECT parameters, can control the 
error recovery processing (retries) of the HDD with respect to each type of error 
related to the disk drive. 
Table 6.7 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 4.1.4) concerning details of the functions of each 
parameter.  The INIT can issue the MODE SELECT or MODE SELECT