Seagate ST3285N, Руководство по эксплуатации продукта

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3.4.5 Reassign Blocks command (07
H
)
When the drive receives the Reassign Blocks command, it reassigns
defective logical blocks to available spare sectors. Use this command
when the AWRE and ARRE bits are set to 0, which means that automatic
reallocation is disabled. These bits are contained in byte 2 of the Error
Recovery page, which is described in Appendix C.1.
If the system supports disconnection, the drive disconnects while exe-
cuting this command. The initiator uses this command to immediately
reallocate any block (sector) that requires the drive to recover data using
ECC if the automatic reallocation feature is not enabled.
Note. Before sending this command, the initiator should recover the data
from the logical blocks to be reassigned. After completing this
command, the initiator can write the recovered data to the same
logical block addresses.
After sending the Reassign Blocks command, the initiator transfers a
defect list containing the logical block addresses to be reassigned. The
drive reassigns the logical blocks. The data contained in the logical
blocks is not preserved.
The drive can repeatedly assign a logical block to multiple physical
addresses until there are no more spare locations available on the disc.
If the drive does not have enough spare sectors to reassign all of the
defective logical blocks, the command terminates with a check condition
status and the sense key is set to media error. The logical block address
of the first logical block not reassigned is returned in the information bytes
of the sense data.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 0 1 1 1
1 LUN 0 0 0 0 0
2 0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 0 0 0 0 0 0 0 0
5 0 0 0 0 0 0 Flag Link
42 ST3655 Family SCSI Drives Product Manual, Rev. A