Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications page 148

Command Specifications
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Immed (Immediate)
"1" : If "1" is specified in the Immed (immediate) bit, at the point when the CDB's legality is
confirmed, or at the point when transfer of the defect list is completed, a "GOOD" status
is reported.
"0" : If "0" is specified in the Immed (immediate) bit, the specified operation is executed and
the status is reported at the point when that operation is completed, then the command is
terminated.
•
Defect list length
This field specifies the total number of bytes in the "Defect list" transferred from the INIT
following the header. The byte length of the "Defect descriptor" which configures the defect
list differs depending on its format and the value specified by this field must be a multiple of 4
when the defect descriptor is in the block address format, and must be a multiple of 8 when the
defect descriptor is in the byte distance from the index format or the physical sector address
format. When zero is specified in this field, it indicates that the defect list is not transferred.
Note:
The disk media defect processing method implemented during FORMAT UNIT command
execution is specified by the CDB and by header of the format parameters transferred from
the INIT. By specifying zero in the "Defect list length" field in the Format parameter
header, the INIT can specify the control flags related to formatting processing without
transferring the defect list (D List).
b. Defect list (D List)
The defect list (D List) contains defect position information about the disk media specified by the
INIT and is configured from one or more "Defect descriptors." "Defect descriptors must be
described in the format specified in the "Defect List Format" field of the CDB.
The configurations which it is possible to specify for the "Defect descriptors" in the defect list (D
List), and their description formats, are shown below. Furthermore, it is possible only to specify
User Space address information on the disk media in the Defect list (D List).
•
Byte distance from the index format defect descriptor
Figure 3.24 shows this description format of the defect descriptor. Defect descriptor in this
format specifies the cylinder number, head (track) number and byte distance to the top byte of
those data (8 bytes), of the data which includes defective bits, on the disk media. One defect is
treated as a defect with a length of 8 bytes (64 bits length). Therefore, for defects with a length
which exceeds 8 bytes, 2 or more defect descriptors must be specified. When multiple defect
descriptors are specified, the cylinder number must be specified in the top position, the byte
distance from the index in the bottom position, and the defect positions listed in ascending
order.
3-86 C141-C010