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Command Specifications
When the specifications in the "Logical block address" field and "Transfer block
count" field in the CDB exceed the maximum logical block address in the IDD,
that command is terminated with a CHECK CONDITION status (ILLEGAL
REQUEST [=5] / Logical block address out of range [=21-00]) and the reading of
data from the disk media is not executed.
Error recovery processing during execution of this command can be specified by
the MODE SELECT parameter. If retry processing and data correction
processing are not prohibited, when this command is completed normally, or
when it is completed with a "RECOVERED ERROR [=1]" sense key report, the
data transferred to the INIT by this command are error free. When a correctable
error check is detected, the IDD first corrects the data errors in the data buffer,
then transfers those data to the INIT.
If the Look-Ahead cache feature is permitted, a caching operation is performed
using the IDD's data buffer by this command. See Chapter 3, "Data Buffer
Management," concerning details of data buffer operation and the Look-Ahead
cache feature.
4.2.2 READ EXTENDED (28)
Bit
Byte
0
1
2
3
4
5
6
7
8
9
This command reads the number of blocks of data in continuous logical data
blocks specified in the "Transfer block count" field with the logical data block on
the disk media specified in the "Logical block address" field in the CDB as the
top.
4-144
7
6
5
0
0
0
Logical Block Address (MSB)
Logical Block Address
Logical Block Address
Logical Block Address (LSB)
0
0
0
Transfer Block Count (MSB)
Transfer Block Count (LSB)
0
0
0
4
3
2
X'28'
×
FUA
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
C141-C012
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