Quantum DLT 2000, Руководство по эксплуатации продукта

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DLT2000 SCSI Interface
DLT2000/DLT2700 Cartridge Tape Subsystem 8-9
ABORT (06h)
This message is sent from the initiator to the target to clear, on the selected unit, the
current I/O process. Buffered (cached) write operations will be completed if possible.
The target goes directly to the BUS FREE phase after successful receipt of this
message. Current settings of Mode Select parameters and reservations are not affected.
Commands, data, and status for other initiators is not affected.
This message can be sent to a logical unit that is not currently performing an operation
for the initiator. If no unit has been selected, the target goes to BUS FREE and no
commands, data, or status on the target is affected.
ABORT TAG (0Dh)
This message is sent from the initiator to the target to clear, on the selected unit, the
current I/O operation only. The target goes directly to the BUS FREE phase after
successful receipt of this message. Current settings of Mode Select parameters and
reservations are not affected. The data on the cache will be flushed to the tape.
BUS DEVICE RESET (0Ch)
This message from an initiator clears all commands, data, and status in the tape
controller. When it recognizes this message, the drive flushes the cache to tape and
proceeds to the BUS FREE state. The drive then executes a hard reset which leaves it as
if a Bus Reset had occurred. All data in the write buffer will be flushed to the media.
CLEAR QUEUE (0Eh)
This message clears all I/O processes for all initiators. A Unit Attention condition will
be generated for all other initiators that had outstanding I/O processes, with Additional
Sense Code (ASC) of Command Cleared by Another Initiator. The target goes directly
to the BUS FREE phase after successful receipt of this message. Current settings of
Mode Select parameters and reservations are not affected. The data on the cache will be
flushed to the tape.
COMMAND COMPLETE (00h)
This message is sent from a target to an initiator to indicate that the execution of a
command (or a series of linked commands) has completed and valid status has been
sent to the initiator. After it has sent the message successfully, the target goes to the
BUS FREE phase by releasing BSY. If received by the tape unit, it is handled as an
illegal message; the drive returns MESSAGE REJECT and enters the STATUS phase
reporting CHECK CONDITION with the sense key set to COMMAND ABORTED.
DISCONNECT (04h)
A target sends DISCONNECT to tell an initiator that the present physical path is going
to be broken (the target intends to disconnect by releasing BSY). Later, reselection is
required in order to complete the current operation. This message does not cause the
initiator to save the Data pointer.