Optical Drive and Library SCSI-2 Command Reference

SCSI Command Overview
Drive Control Commands
Chapter 1 1-15
SCSI Command OverviewSCSI Command Overview
Busy 08H
A busy status is returned by the target during powerup until all poweron
diagnostic tests have been completed. A busy status is also returned
when multiple commands are outstanding in the target, and a media
access command is received with the DISC PRIV bit cleared in the
identify message.
Intermediate/Good 10H
Unless an error, exception, or abnormal condition causes a Check
Condition status or a Reservation Conflict status, the Intermediate Good
status is returned for every command in a series of linked commands,
excluding the last command. If this status is not returned, the chain of
linked commands is broken; no further commands in the series are
executed.
Intermediate Condition Met 14H
This status is the combination of the Condition Met and the
Intermediate statuses.
Reservation Conflict 18H
This status is returned when a SCSI device attempts to access a logical
unit that is reserved for another initiator.
Queue Full 28H
This status is returned when a Simple Queue Tag, Ordered Queue Tag,
or a Head of Queue Tag message is received and the command queue of
the drive is full. The I/O process is not placed in the command queue. The
drive can handle 32 I/O processes at a time.