User's Guide

Page 104 DDS-4 SCSI Interface Manual, Rev. B
PREVENT/ALLOW MEDIA REMOVAL (1Eh)
If the Prevent/Allow Media Removal command is sent, the cartridge cannot be
ejected using the Eject button on the front of the drive. After a Reset, the default
state of the drive is in the ALLOW command mode. An UNLOAD command ejects
the cartridge even after a PREVENT command.
PREVENT/ALLOW MEDIA REMOVAL Command Descriptor Block
The following table shows the layout of the CDB.
Byte
Bits
7 6 5 4 3 2 1 0
0 0 0 0 1 1 1 1 0
1 0 0 0 0 0 0 0 0
2 0 0 0 0 0 0 0 0
3 0 0 0 0 0 0 0 0
4 0 0 0 0 0 0 0 PRVNT
5 vendor unique* 0 0 0 0 Flag Link
* This vendor-unique field is reserved and must be set to zero.
Command Descriptor Block Field Description
If the prevent (PRVNT) bit (byte 4, bit 0) is 1, the cartridge cannot be ejected using
the front-panel Eject button. If the PRVNT bit is 0, the Eject button is enabled.
Completion Status
The Completion Status for the PREVENT/ALLOW MEDIA REMOVAL command is
shown in the following table.
Code Message Description
00h Good Status • The drive is ready to perform any appropriate command.
• The drive remains in any previously set mode.
• The tape position is not changed.
• If a PREVENT command was issued, the amber drive LED is always
ON. The cartridge cannot be removed.
• If an ALLOW command was sent, the drive LED is ON only when the
tape is accessed. The tape can be removed at BOT without setting
Unit Attention Condition.
02h Check Condition Extended Sense Byte 02h:
Code Message Description
04h Hardware Error Drive hardware failure detected.
05h Illegal Request The CDB or Parameter List contains an
invalid bit.
06h Unit
• Cartridge was changed prior to
Attention accepting this command.
• The drive was reset prior to this
command.