IBM IC35L018UCDY10, Specifications

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8.28 REQUEST SENSE (03h)
LINK FLAG Reserved = 0 VU = 0 5
Allocation Length 4
Reserved = 0
2
3
Reserved = 0 Reserved = 0 1
Command Code = 03h 0
0 1 2 3 4 5 6 7
Bit
Byte
Figure 151. REQUEST SENSE
The REQUEST SENSE command requests the drive to transfer sense data.
The sense data shall be available under the following conditions:
!
The previous command to the specified I_T_L nexus
4
terminated with CHECK CONDITION status. All
other information (e.g. medium position) is available in any fields.
!
The previous command to the specified I_T_L nexus ended unexpected BUS FREE error.
If REQUEST SENSE command with an invalid LUN is received, the drive returns GOOD status and
reports a sense key of ILLEGAL REQUEST and an additional sense code of LOGICAL UNIT NOT
SUPPORTED.
If the drive has no sense data available to return, it shall return a sense key of NO SENSE and an addit-
ional sense code of NO ADDITIONAL SENSE INFORMATION.
The sense data shall be preserved by the drive for the initiator until retrieved by the REQUEST SENSE
command or until any other command for the same I_T_L nexus. Sense data shall be cleared upon re-
ceiving a subsequent command including REQUEST SENSE to the same I_T_L nexus.
Separate sense data is maintained by the device for each initiator. Therefore, there is no requirement for
an initiator to expeditiously clear a CHECK CONDITION as this will not affect other initiators in a multi-
initiator system.
The drive will return the number of bytes in the allocation length or 32 bytes whichever is less.
The contents of the sense data is defined in Section 12.0, "SCSI Sense Data" on page 215.
Ultrastar 146Z10 hard disk drive specifications
151
4
A nexus which exists between an initiator, a drive, and a logical unit.