Media Defect Management
Embedded SCSI Disk Drives
The FORMAT UNIT command formats the media so that all data
blocks can be accessed. The following lists are used during the
defect management process.
Primary, or Manufacturer's, Defect List (P list)
The P list supplied by the manufacturer is resident on the disk
drive. The initiator can reference this list with the READ DEFECT
DATA command. The initiator cannot change or erase the Primary
list.
Certification Defect List (C list)
The C list is the position information of defective data blocks
detected during data block verification after initialization when the
FORMAT UNIT command is issued. These defects are added to
the Grown list.
Data Defect List (D list)
The D list is the defect position information transferred from the
initiator upon execution of the FORMAT UNIT command. These
defects are added to the Grown list.
Grown Defect List (G list)
The G list includes defects identified to, or by, the drive. It does
not include the P list. These defects are classified as flaws
appearing after the media is formatted. The initiator may request
that the current G list be used during formatting, or that the current
G list be erased and a new list begun. Entries to the G list include:
- Defects provided to the drive in D lists during previous
FORMAT UNIT commands.
- Drive C list defects detected during previous FORMAT
UNIT commands.
- Defects appended by successful completion of the
REASSIGN BLOCKS command.
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