Seagate ST3285N, Руководство по эксплуатации продукта

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3.4.3 Request Sense command (03
H
)
The Request Sense command requests that the drive transfer sense data
to the initiator in the additional sense data format. The additional sense
format is described in Appendix C.
The sense data applies to the previous command on which a check
condition status was returned. This sense data is saved for the initiator
until:
•
The initiator requests the sense data using the Request Sense com-
mand, or
•
Another command is received from the initiator that issued the com-
mand, resulting in the check condition status.
If any of the following fatal errors occur during a Request Sense com-
mand, the drive sends a check condition status and the sense data may
be invalid.
•
The drive receives a nonzero reserved bit in the CDB.
•
An unrecovered parity error occurs on the data bus.
•
A malfunction prevents return of sense data.
If any other error occurs during the Request Sense command, the drive
returns sense data with good status.
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 1 1
1 LUN 0 0 0 0 0
2 0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 Allocation length
5 0 0 0 0 0 0 Flag Link
Byte 4 The allocation length specifies the maximum number of bytes
the initiator has allocated for returned sense data. The drive
returns up to, but no more than, 22 bytes of sense data. There-
fore, if you want the initiator to receive all of the sense data, set
the allocation length to 22 bytes or more. If you set the allocation
length to zero, no sense data is returned.
ST3655 Family SCSI Drives Product Manual, Rev. A 35