6.Command Specification | LOAD/UNLOAD |
6.3.LOAD/UNLOAD 1Bh
Bit | 7 | 6 |
| 5 | 4 |
| 3 | 2 | 1 | 0 |
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0 |
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| Operation | Code (1Bh) |
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1 |
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| Reserved |
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| IMMED | ||
2 |
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3 |
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4 |
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| HOLD | EOT (0) | RETEN | LOAD | |
5 |
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| Control |
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The LOAD/UNLOAD command requests that the drive enable or disable the media for further operations. This command may also be used to request a retension function.
IMMED: If this bit is set, status is returned as soon as the load or unload operation is initiated. Otherwise, the status is returned after the operation has completed.
LOAD: A LOAD bit of one and a HOLD bit of zero indicates the medium in the drive will be loaded and positioned to the
A LOAD bit of one and a HOLD bit of one indicates if the medium has not been moved into the logical unit, the medium will be moved in but not positioned for access. The EOT and RETEN bits will be set to zero. Following successful completion, the drive will return GOOD STATUS. If both the medium and drive support MAM, the drive will generate a unit attention condition for all initiators with the ASC and ASCQ set to MEDIUM AUXILIARY MEMORY ACCESSIBLE.
A LOAD bit of zero and a HOLD bit of one indicates if the medium is in the drive, the medium will be unthreaded but will not be ejected. Following successful completion, the drive will return GOOD STATUS. If both the medium and drive support MAM, the drive will generate a unit attention condition for all initiators with the ASC and ASCQ set to MEDIUM AUXILIARY MEMORY ACCESSIBLE.
RETEN: A RETEN bit of one indicates that the drive unit will perform a retension function on the current medium. A RETEN bit of zero indicates that the drive will not perform a retension function on the current medium.
EOT: An
HOLD: A HOLD bit of one indicates MAM will be accessible upon completion of the command but the medium will not be positioned for access. A HOLD bit of zero and a LOAD bit of one indicates the medium will be positioned for access. A HOLD bit of zero and a LOAD bit of zero indicates MAM will not be accessible upon completion of the command.
If the drive has received an UNLOAD command with the Immediate bit set and then receives either another command which would involve tape motion or TEST UNIT READY, the drive will return a CHECK CONDITION status with a NOT READY sense key set.
SONY |