Quantum LTO 4, User Manual

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SCSI Commands: 24BPARK UNPARK Page 113
3.12 PARK UNPARK
The PARK UNPARK command with the park bit set requests that the drive park the
load arm in preparation for transport.
The PARK UNPARK command with the park bit not set requests that the drive load
arm be unparked. This is not usually necessary as the drive automatically unparks
on power up.
In either case, attempting to issue this command while the medium is present will
result in a vendor specific check condition of MEDIUM_IS_PRESENT (09/80/80).
The PARK UNPARK command is a vendor unique command.
3.12.1 PARK UNPARK Command Descriptor Block
Byte
Bits
7 6 5 4 3 2 1 0
0 Operation Code (06h)
1 Ignored LUN Reserved
2 Reserved
3 Reserved
4 Reserved Park
5 Control
3.12.1.1 PARK UNPARK Command Field Descriptions
Field Bytes Bits Description
Operation
Code 0 The Operation Code for PARK UNPARK is 06h.
Ignored
Logical
Unit 1 5-7 The LUN field is vestigial from the SCSI-1 standard and is
ignored.
Park 4 0 0b = Requests the drive to be unparked.
1b = Requests the drive to be parked.
Reserved All reserved bits must be 0.
Control 5 See SCSI Command Control Byte Format on page 25.
3.12.2 PARK UNPARK Completion Status
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.
02h Check Condition Use the REQUEST SENSE command to retrieve status information.
Possible Sense Keys are:
Code Message Description
04h Hardware Error Drive hardware failure.
05h Illegal Request The Command Descriptor Block is invalid.
06h Unit Attention The cartridge was changed, or the drive
was reset prior to this command.
09h Medium Present Cannot park drive with medium present.