Fujitsu MAP3147 Computer Drive User Manual


 
Command Specifications
3 -
86
C141-E167
Note:
Copying of the contents of data in the logical data blocks specified in the “Defect data” list to
alternate blocks allocated by this command is attempted, but in some cases, copying cannot be
done. Confirmation of the contents of the data in allocated alternate blocks, saving of data
before issuing this command and restoring of data after this command is executed are the
responsibility of the INIT.
The format of the “Defect Data” list transferred from the INIT by this command is shown in Figure
3.16.
Bit
Byte
76543210
0 X‘00’
1 X‘00’
2 Defect List Length (m) (MSB)
3 Defect List Length (m) (LSB)
4 Defective Block Logical Block Address (MSB)
5 Defective Block Logical Block Address
6 Defective Block Logical Block Address
7 Defective Block Logical Block Address (LSB)
8
Defective Block Logical Block Address
n+3
Figure 3.16 REASSIGN BLOCK command: defect data list configuration
The “Defect data” list is configured from a 4-byte header and one or more defect descriptors which
follow it. One defect descriptor has a length of 4 bytes.
The “Defect list length” field in the header indicates the total number of bytes (m) of the defect
descriptor list transferred after the header, and must be a multiple of 4. Also, when zero is specified
in this field, this command is terminated without transfer of the defect descriptor list and allocation
processing of alternate blocks.
Note:
The Defect list length that can be specified for the IDD is 2,044 (X ‘7FC’) bytes or less.
Therefore, a maximum of 511 defective blocks can be specified in the REASSIGN BLOCKS
command.
~
~
~
~
Header
Defect
Descriptor
List
~
~