Seagate ST3285N, Product Manual

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3.4.4.3 Defect list header and defect list
The defect list, shown below, contains a 4-byte header, followed by one
or more defect descriptors. Byte 1 of the defect list header determines
whether the P and C defects are reallocated.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 0
1 FOV DPRY DCRT STPF 0 0 0 0
2–3 Defect list length
4–n Defect descriptor
Byte 1 If the
FOV bit is 1, the DPRY, DCRT and STPF bits are
interpreted. If the FOV bit is 0, the DPRY, DCRT and STPF
bits are checked for zeros.
If the DPRY bit is 1, the defects described in the P-list are
not reallocated during formatting. This means existing real-
locations of the P-list are canceled and no new reallocations
are made during formatting. The P-list is retained. If the
DPRY bit is 0, the defects described in the P-list are
reallocated during formatting. A check condition status is
sent if the P-list cannot be found.
If the DCRT bit is 1, the drive does not verify the data written
during the format. Therefore, no C-list for this format is
created or reallocated. If the DCRT is 0, the drive verifies
the data written during the format, creates a C-list and
reallocates sectors that were incorrectly formatted.
If the STPF bit is 1, the drive stops formatting if it encounters
an error while accessing either the P or G defect list. If the
STPF bit is 0, the drive continues formatting even though it
has encountered an error while accessing either the P or G
defect list.
Bytes 2–3 The
defect list length is the length, in bytes, of the defect list
that follows the header. For each sector to be reallocated,
the defect list contains 1 defect descriptor containing
8 bytes in either the bytes-from-index format or the physical
sector format. These formats are explained in Sec-
tions 3.4.4.4 and 3.4.4.5, respectively.
Bytes 4–n The two types of defect descriptors are described in Sec-
tions 3.4.4.4 and 3.4.4.5.
ST3655 Family SCSI Drives Product Manual, Rev. A 39