Quantum DLTtape DLT 7000, Product Manual

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Messages
Quantum DLT 7000 Tape System 4-7
4.2.5 IDENTIFY Message (80h - FFh)
The IDENTIFY message is sent by either the initiator or the drive to establish or
re-establish the physical connection path between an initiator and target for a
particular logical unit under the conditions listed below. Figure 4–2 shows the
format of the IDENTIFY message and Table 4–5 describes the data field
contents.
Bit
Byte
7 6 5 4 3 2 1 0
Identify DiscPriv LUNTAR Reserved LUNTRAN
Figure 4–2 IDENTIFY Message - Data Format
Table 4–5 IDENTIFY Message - Field Description
Field Description
Identify The Identify bit must be set to 1. This identifies the message as an IDENTIFY
message.
DiscPriv Disconnect Privilege. The DiscPriv can be 0, provided that no other I/O process
is currently active in the drive. If not set to 1 and other I/O processes are
currently active in the drive, the drive returns BUSY status.
LUNTAR The Logical Unit/Target Routine (LUNTAR) field must be set to zero. The drive
supports a single Logical Unit Number (LUN 0). A LUNTAR bit of one causes
the drive to send a MESSAGE REJECT message and switch to the BUS FREE
phase.
Reserved The Reserved bits must be zero. If a Reserved bit is non-zero, the drive returns
a MESSAGE REJECT message and switches to the BUS FREE phase.
LUNTRN Logical Unit Number.