6.Command Specification

LOAD/UNLOAD

6.3.LOAD/UNLOAD 1Bh

Bit

7

6

 

5

4

 

3

2

1

0

Byte

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

Operation

Code (1Bh)

 

 

 

1

 

 

 

 

Reserved

 

 

IMMED

2

 

 

 

 

 

Reserved

 

 

 

3

 

 

 

 

 

Reserved

 

 

 

4

 

 

Reserved

 

 

HOLD

EOT (0)

RETEN

LOAD

5

 

 

 

 

 

Control

 

 

 

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 retention 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 shall be loaded and positioned to the beginning-of-partition zero. A LOAD bit of zero and a HOLD bit of zero indicates the medium in the drive shall be positioned for removal at the extreme position along the medium specified by the EOT bit.

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 shall be moved in but not positioned for access. The EOT and RETEN bits shall be set to zero. Following successful completion, the drive shall return GOOD STATUS. If both the medium and drive support MAM, the drive shall generate a unit attention condition for all initiators with the additional sense code and additional sense code qualifier 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 shall be unthreaded but shall not be ejected. Following successful completion, the drive shall return GOOD STATUS. If both the medium and drive support MAM, the drive shall generate a unit attention condition for all initiators with the additional sense code and additional sense code qualifier set to MEDIUM AUXILIARY MEMORY ACCESSIBLE.

RETEN: A RETEN bit of one indicates that the drive unit shall perform a retention function on the current medium. A RETEN bit of zero indicates that the drive shall not perform a retention function on the current medium.

EOT: An end-of-tape (EOT) bit of one and a Load bit of ZERO indicates that the medium shall be positioned at end-of-medium for removal from the peripheral device. Prior to performing the unload operation, any buffered data that is to be written shall be transferred to the medium. An EOT bit of ZERO and Load bit of ZERO indicates that the medium shall positioned at beginning-of-medium for removal etc. This drive does not support this bit. EOT bit of one shall cause the target to return CHECK CONDITION status. The sense key shall be set to ILLEGAL REQUEST and the additional sense code shall be set to ILLEGAL FIELD IN CDB. This field is not supported. This field should be set to 0.

HOLD: A HOLD bit of one indicates MAM shall be accessible upon completion of the command but the medium shall not be positioned for access. A HOLD bit of zero and a LOAD bit of one indicates the medium shall be positioned for access. A HOLD bit of zero and a LOAD bit of zero indicates MAM shall 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.

6-8

SONY AIT-3Ex drive SDX-800V series Ver.1.1

Page 66
Image 66
Sony SDX-800V/R manual LOAD/UNLOAD 1Bh, Immed, Hold, Reten Load