Operating instructions

13-2
SCSI REFERENCE 1012975
CHAPTER 13—PREVENT/ALLOW MEDIUM REMOVAL (1Eh)
When the Prevent bit is set to 01b, an interlock mechanism on the cartridge
access port door activates to prevent the door from being opened until one of
the following occurs:
 All initiators that have issued PREVENT MEDIUM REMOVAL commands
issue ALLOW MEDIUM REMOVAL commands with the Prevent bit set to 0.
 The autoloader is reset (see Section 3.2 on page 3-2 for information about
autoloader resets).
13.3 COMMAND STATUS
The autoloader returns a status byte after processing the PREVENT/ALLOW
MEDIUM REMOVAL command. This section describes when each type of
status byte might be returned.
Good
The autoloader returns Good status when it is able to process the command
without errors.
Busy
The autoloader returns Busy status when it is processing a command for a
different initiator or when it is in the process of aborting a motion command.
Reservation Conflict
The autoloader returns Reservation Conflict status when it is reserved by a
different initiator and a request is made to prevent medium removal. See
Chapter 20 for more information about the RESERVE command.
Check Condition
The autoloader returns Check Condition status when:
 The message system is enabled and a message error occurs while the
autoloader is processing the command.
 The autoloader detects an unrecoverable parity error while receiving the
CDB.
 The command is issued to an invalid LUN.
 A Unit Attention condition is pending for the initiator.
 A reserved bit is set to 1 in the CDB.
Table 13-1 Invalid parameters in the PREVENT/ALLOW MEDIUM REMOVAL CDB
Sense
Key
ASC ASCQ
SKSV
Bit
C/D
Bit
BPV
Bit
Bit
Pointer
Field
Pointer
Error
5h 24h 00h 1 1 1 — —
A reserved bit is set in the CDB. The
pointers point to the bit in error.