Technical information

HGST Ultrastar C15K600 Hard Disk Drive Specification
228
18.27
REASSIGN BLOCKS (07)
Table 204 REASSIGN BLOCKS (07)
Byte
Bit
7
6
5
4
3
2
1
0
0
Command Code = 07h
1
Reserved = 0
LONGLBA
Reserved = 0
2-4
Reserved = 0
5
VU = 0
Reserved = 0
FLAG
LINK
The REASSIGN BLOCKS command requests the drive to reassign a logical block to an available spare. The
REASSIGN BLOCKS command attempts to allocate spare blocks on a spare track. The LBA is transferred to the
drive during the DATA OUT phase. One to four blocks may be specified for relocation per REASSIGN BLOCKS
command.
Reassignment is complete upon the completion of the REASSIGN BLOCKS command. At this time, the defective
logical block address has been added to the Glist.
All data is preserved during a reassign command except for the target LBA data. The Mode Page 0h DRRT (Disable
Restore Reassign Target) bit determines if the reassign blocks command will attempt to recover the Target LBA data.
If the Target cannot recover the data at the Target LBA then the Initiator will have to restore the data after the
REASSIGN BLOCKS command completes successfully.
If the reassignment begins to move data and is interrupted or fails to complete successfully, the Target enters a
degraded mode of operation. In this mode data can be read but writing to the drive is prohibited.
Upon successful completion of this command, the location of the physical sectors reassigned during the command
are added to the Glist. The reassigned sectors are marked defective and cannot be accessed again until after a
format operation discards the Glist.
- LONGLBA bit of zero indicates that LBAs in the provided defect list are 4-bytes. A LONGLBA bit of one
indicates that the LBAs in the provided defect list are 8-bytes