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The IDD allocates alternate blocks to the specified data blocks in order from the
top of the defect descriptor list. When all the usable spare sectors have been used
up, and it is 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:
• Additional sense code/:
Additional sense code qualifier
• "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).
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 (Section 4.3.3).
C141-C009
4.3 Format Commands
4 = HARDWARE ERROR
32-00 = No defect spare location available
"1"
Logical block address specified in the defect
descriptor at the point when alternate block
allocation becomes impossible.
4-159
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