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The logical block address of defective data blocks is described in 4-byte format in the defect
descriptor. When multiple defect descriptors are specified, it is best for the INIT to describe
defect descriptors in the ascending order of the logical data block addresses.
Furthermore, if the addresses of logical data blocks specified in the defect descriptor list
overlap each other, This command is terminated with a CHECK CONDITION status
(ILLEGAL REQUEST [=5] / Invalid field in parameter list [=26-00] and none of the alternate
block allocation processing in that command is executed.
The IDD allocates alternate blocks to the specified data blocks in order from the top of the
defect descriptor list.
impossible to allocate alternate blocks, execution of this command is terminated at that point
and a CHECK CONDITION status is reported. The sense data at this time indicate the
following contents.
• Sense key:
• Sense code/Sub-sense code: 32-00 = No defect spare location available
• "VALID" bit:
• Information field
• Command inherent information field
Also, when this command is terminated abnormally with a CHECK CONDITION status due
to any one of several other types of error besides the above error, the logical block address
specified in the first defect descriptor which did not undergo alternate block allocation is
reported in the "Command inherent information" field in the sense data. However, if alternate
block allocation processing of the defect descriptors for which alternate block allocation has
not been implemented cannot be specified, or if alternate block allocation of all the specified
defect descriptors has been completed, the "Command inherent information" field indicates X
'FFFFFFFF.'
When alternate block allocation processing is successful, the defect position information on
the disk media related to the data blocks specified in the defect descriptor list is recorded on
the disk media as the defect list (G List). The INIT can read the contents of the G List using
the READ DEFECT DATA command. Also, this command has no influence on the contents
of the primary defect list (P List).
Note:
The defect position information in the G List is physical block addresses (logical data
block addresses are allocated when no defect exists on the disk media). Therefore, the
values specified in this command's defect descriptor list (logical block addresses) may not
necessarily be the same as the contents of the G List read by the READ DEFECT DATA
command after this command is terminated. For details, see the description of the READ
DEFECT DATA command (item 3.3.3).
3 - 106
When all the usable spare sectors have been used up, and it is
4 = HARDWARE ERROR
"1"
Logical block address specified in the defect
descriptor at the point when alternate block
allocation becomes impossible.
C141-E039-01EN
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