SCSI Commands
5-188
Quantum DLT 8000 Tape System
REQUEST SENSE Command (03h) (continued)
The REQUEST SENSE command causes the tape drive to transfer detailed sense data to
the initiator.
The sense data is valid for a CHECK CONDITION or RESERVATION CONFLICT
status returned on the previous command. The sense data bytes are preserved by the tape
drive until retrieved by a REQUEST SENSE command, or until the receipt of any other
command from the same initiator, though some commands, such as INQUIRY, do not
change sense data.
If the tape drive receives an unsolicited REQUEST SENSE, it returns sense data with
the appropriate values in the End of Media (EOM), Sense Key, Additional Sense Code,
and Additional Sense Code Qualifier. The positional information provided reflects the
logical position of the tape drive. The tape drive returns information based on the non-
diagnostic data in its buffer as well as the data on tape medium. Additionally, bytes 25
through 28 contain the amount of tape to be written in 4 KB blocks.
REQUEST SENSE does not cause the drive to flush its buffered data to tape. Therefore,
if the host requires the exact physical positioning of the tape medium, it should precede
the REQUEST SENSE command with a WRITE FILEMARKS command with length 0
(Immed=0) specified. This forces the tape drive to flush any currently-buffered data to
tape. A subsequent REQUEST SENSE command returns the actual physical (and
logical) position of the tape drive to the initiator.
The following illustration portrays the format of REQUEST SENSE DATA.
Summary of Contents for DLTtape DLT 8000
Page 1: ...DLTTM 8000 Tape System Product Manual Nov 10 2003 81 60118 06...
Page 5: ...USER MANUAL STATEMENTS FOR CLASS B EQUIPMENT continued...
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Page 26: ...Table of Contents xxiv Quantum DLT 8000 Tape System...
Page 36: ...About This Manual Quantum DLT 8000 Tape System xxxii...
Page 54: ...General Description and Specifications 1 18 Quantum DLT 8000 Tape System...
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Page 376: ...Appendix A Definition of Vendor Unique Sense Data Information A 4 Quantum DLT 8000 Tape System...
Page 386: ...Appendix C Updating the Firmware C 6 Quantum DLT 8000 Tape System...
Page 396: ...Appendix E Visual Inspection Procedure for DLTtape Cartridges E 8 Quantum DLT 8000 Tape System...
Page 406: ...Appendix G DLT 7000 Emulation Feature G 8 Quantum DLT 8000 Tape System...
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