DLT1/VS80 SCSI Interface Guide
81-81276-01 Rev A01
July 2004
4-13
4.5
LOAD/UNLOAD (1Bh)
The LOAD/UNLOAD command tells the target to load or unload the media in the data cartridge. If no
cartridge is present in the tape drive, both LOAD and UNLOAD return CHECK CONDITION status
with a NOT READY Sense Key set. If the tape drive has received an UNLOAD command with the
Immed bit set, and then receives another command involving medium motion or TEST UNIT READY,
the tape drive returns a CHECK CONDITION status with a NOT READY Sense Key set.
Operation of the UNLOAD version of this command is different if a media loader is present.
Two modes of operation are possible when a media loader is attached. If the media loader has issued
no media loader-specific commands, the tape drive operates in the sequential mode of operation. When
a media loader has issued a media loader-specific command and the tape drive has accepted it, the tape
drive disables the sequential mode of operation and the UNLOAD command becomes a NO–OP.
If the tape drive is in the default sequential mode of operation and the subsystem receives an
UNLOAD command, the tape drive unloads the current data cartridge and the media loader
automatically moves it to the magazine slot from which it originated. The media loader automatically
moves the data cartridge from the next slot in the magazine, if not empty, from the magazine into the
tape drive, which loads it and prepares it for use. If the next magazine slot is empty, no CHECK
CONDITION status is created.
When the media loader moves an unloaded data cartridge into the last magazine slot), the subsystem
does not cycle back to slot 0. This prevents accidental overwriting of data when using the subsystem in
the sequential auto-loading mode. The user must manually select and load the next data cartridge or
use a SCSI MOVE MEDIUM command.
You can modify EEPROM parameters ENALDRAUTOLD and DISLDRAUTOLDMC to enable or
disable the sequential loading feature (see
Section 4.10.10, “EEPROM Vendor Unique Page (3Eh)”
).
Содержание DLT1/VS80 SCSI
Страница 1: ...DLT1 VS80 SCSI Interface Guide...
Страница 5: ...DLT1 VS80 SCSI Interface Guide 81 81276 01 Rev A01 July 2004 v Taiwan Statement Japanese Notice...
Страница 6: ...DLT1 VS80 SCSI Interface Guide vi July 2004 81 81276 01 Rev A01 Notes...
Страница 12: ...Table of Contents xii July 2004 81 81276 01 Rev A01 Notes...
Страница 16: ...List of Figures xiv July 2004 81 81276 01 Rev A01 Notes...
Страница 20: ...List of Tables xviii July 2004 81 81276 01 Rev A01 Notes...
Страница 24: ...Chapter 1 Introduction 1 4 July 2004 81 81276 01 Rev A01 Notes...
Страница 32: ...Chapter 2 General SCSI Bus Operation 2 8 July 2004 81 81276 01 Rev A01 Notes...
Страница 42: ...Chapter 3 SCSI Messages 3 10 July 2004 81 81276 01 Rev A01 Notes...
Страница 181: ......
Страница 182: ...4001 Discovery Dr Ste 1100 Boulder CO 80303 720 406 5700 July 2004 81 81276 01 Rev A01 81 81276 01 81 81276 01...
