User's Manual

Disk Media Management
394 C141-C013
(2) FORMAT UNIT command
Issue the FORMAT UNIT command in either of the following two formats and
initialize the entire disk media surface.
a) Specify "1" in the "FmtData" bit, "0" in the "CmpLst" bit and "000" in the
"Defect List Format" field. Also, prepare only a 4-byte header, specify "0" in
the "FOV," "DPRY," "DCRT" and "STPF" bits and zero in the "Defect List
Length" field.
− In this FORMAT UNIT command, the entire disk media surface is
initialized using the P List and the previously existing G List, then after
initialization, the data blocks are verified. If any defective blocks are
detected in the Verify operation, alternate blocks are allocated for those
data blocks. Also, the previously existing G List is saved, and the defect
position information for the defective data blocks detected in the Verify
operation is added to the G List. During initialization, alternate blocks
for which sector slip processing was applied for previously known
defects are reallocated, so optimization of the logical data block locations
on the disk media can be expected.
b) Specify "0" in the "FmtData" bit and in the "CmpLst" bit and "000" in the
"Defect List Format" field. In this case, specification of the format
parameters is not necessary.
− In this FORMAT UNIT command, the disk media is initialized using
only the P List, then after initialization, the data blocks are verified. If
any defective blocks are detected in the Verify operation, alternate
blocks are allocated for those data blocks. Also, the previously existing
G List is erased and defect position information for the defective data
blocks detected in the Verify operation is recorded in a new G List.