SCSI Commands
Page
71
PREVENT ALLOW MEDIA REMOVAL
The Prevent Allow Medium Removal command requests that the target enable or
disable the removal of the medium from the drive. The drive will not allow medium
removal if any initiator currently has medium removal prevented.
If medium removal is prevented and the medium is in the loaded position, then:
•
Pressing the eject button on the front panel will be ignored.
•
The Load Unload command with the LOAD bit set to zero will result in a Check
Condition status. The sense code is set to Illegal Request and the Additional
Sense to Medium Removal Prevented (5302).
All initiators that have prevented medium removal must enable it before the medium
can be removed from the drive.
A bus reset, BDR message or power cycle will clear any previous medium removal
prevented setting and allow medium removal.
Command Descriptor Block
Byte
Bits
7
6
5
4
3
2
1
0
0
Operation Code (1Eh)
1
Ignored LUN Reserved
2
Reserved
3
Reserved
4
Reserved
Prevent
5
Control
Field Descriptions
Field
Bytes
Bits
Description
Operation
Code
0
The Operation Code for Prevent/Allow Medium Removal is 1Eh.
Ignored
Logical
Unit
1
5-7
The LUN field is residual from the SCSI-1 days and is ignored.
Prevent
4
0-1
00b = Medium removal allowed.
01b = Medium removal prevented.
10b = Not supported, no medium changer.
11b = Not supported, no medium changer.
Reserved
All reserved bits must be 0.
Control
5
See Control Byte Format on page 18.