Reserve Command; Rezero Unit Command - Sony CDU-541 Interface Manual

CDU-541 CD-ROM DRIVE SCSI INTERFACE MANUAL
An
initiator that holds a current reservation may modify that reservation by
issuing another RESERVE command to the same logical unit. The superseding
RESERVE command will release the previous reservation when the new reservation
~equest is granted. The current reservation will not be modified if the new
~eservation
request cannot be granted. If the superseding reservation cannot
be granted because of conflicts with a previous active reservation (other than
the reservation being superseded), then the controller will return RESERVATION
CONFLICT status.
5.2.29.
REZERO UNIT Command
==============================================================================
Bitl
Byte
I
7
6
5
4
3
2
1
o
==============================================================================
o
I
Operation Code (Olh)
I
-----1-----------------------------------------------------------------------1
1
I
Logical Unit Number
i
Reserved
I
-----1-----------------------------------------------------------------------1
2
1
Reserved :
-----1-----------------------------------------------------------------------1
3 1
Reserved
1
-----1-----------------------------------------------------------------------1
4
1
Reserved
1
-----1-------------------------:---------------------------------------------1
5 I
Control Byte
I
============================================================================::
The REZERO UNIT command requests that the controller position the optical
pick-up at logical block address zero and enter the hold track state for the
duration of the inactivity time.
If the disconnect privilege is granted the controller will disconnect before
performing the seek operation.
If the ready condition does not exist a CHECK CONDITION status will be
~eturned
and the appropriate additional sense code set.
The MODE SELECT parameters will not be changed.
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