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When this bit is "1", it indicated that the IDD shall access the media in performing the command
prior to returning GOOD status. WRITE commands shall not return GOOD status until the
logical blocks have actually been written on the media (i.e., the data is not write cached).
3.2.5
WRITE AND VERIFY (2E
Bit
Byte
0
1
2
3
4
5
6
7
8
9
This command transfers the number of blocks of data specified in the "Transfer block count" field
from the INIT and writes them in continuous logical data blocks with the logical data block on the
disk media specified in the "Logical block address" field in the CDB as the top, then reads those data
and performs a Verify check.
The functions of this command related to write operations are the same as those of the WRITE
EXTENDED command (Section 3.2.4), with the exception that the write cache function cannot be
applied. When zero is specified in the "Transfer block count," this command is terminated normally
without performing seek or pre-fetch.
The specification in bit 4 of CDB byte 1 is disabled in the IDD and the specified value is
disregarded.
If "1" is specified in bit 1 of CDB, the BytChk bit, the IDD writes the transferred data (A) onto the
disk media, then compares the data read from the disk media with the data (A). If the data do not
match during this mode, the command is terminated with a CHECK CONDITION status
(MISCOMPARE [=E] / Miscompare during Verify Operation [=1D-00]).
The IDD does not support this bit. And if "1" is specified in this bit, the IDD reports CHECK
CONDITION status (ILLEGAL REQUEST [=5] / Invalid field in CDB [=24-00]).
The Verify check executed by this command is the ECC (data portion) normalcy check only. error
recovery processing when the verify check is executed is according to the mode specified by the
MODE SELECT parameters (Verify error recovery parameter). For example, if data correction
C141-E167
)
7
6
5
LUN
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
3.2 Data Access Commands
4
3
2
X'2E'
0
0
0
0
0
0
0
0
1
0
BytChk
0
0
0
0
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