Quantum DLT1/VS80 SCSI, Interface Manual

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DLT1/VS80 SCSI Interface Guide
81-81276-01 Rev A01 July 2004 4-85
‘T’ designates data type: ‘b’ specifies binary type, ‘A’ specifies string type, decimal data type if no
value is specified.
4.11 PREVENT/ALLOW MEDIUM REMOVAL (1Eh)
This command enables or disables the unloading of the data cartridge.
Figure 4-56. PREVENT/ALLOW MEDIUM REMOVAL (1Eh) Command Descriptor Block —
Data Format
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (1Eh)
1 Logical Unit Number Reserved
2 - 3 Reserved
4 Reserved Prevent
5 Unused Reserved Flag Link
Table 4-51. PREVENT/ALLOW MEDIUM REMOVAL (1Eh) Command Descriptor Block —
Field Descriptions
Field Name Description
LUN Logical Unit Number. The target ignores this field. Only an IDENTIFY message
can change the LUN.
Prevent When this bit is 1, the Unload button on the tape drive’s front panel is effectively
disabled and the UNLOAD command does not unload the media or the data
cartridge. The PREVENT/ALLOW status in the tape drive is maintained
separately for each initiator.
When the Prevent bit is 0, the Prevent state corresponding to that initiator is
cleared. When all initiators have cleared their Prevent state, the Unload button and
UNLOAD commands are enabled. By default, after power up, a hard reset, or a
BUS DEVICE RESET message, the Prevent Medium Removal function is
cleared.
If a Media Loader is present, the MOVE MEDIUM command is not allowed to
remove a cartridge if PREVENT has been selected. For more details, refer to
Section 5.3, “MOVE MEDIUM (A5h)” on page 5-4