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Product Manual - Disc Drive SCSI-2/SCSI-3 Interface (Vol. 2; Ver. 2), Rev. E
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Only one logical unit number or target routine number shall be identified per I/O process. The initiator may
send one or more IDENTIFY messages during a connection. A second IDENTIFY message with a different
value in either the LUNTAR bit or LUNTRN field shall not be issued before a BUS FREE phase has occurred;
if a target receives a second IDENTIFY message with a different value in either of these fields, it shall go to
BUS FREE phase (unexpected BUS switch to another I/O process. (See the DTDC field of the disconnect-
reconnect page (5.2.1-23) for additional controls over disconnection.)
An implied RESTORE POINTERS message shall be performed by the initiator prior to the assertion of the
ACK signal on the next phase for an IDENTIFY message sent during reconnection.
Initiator Detected Error(05h)
The INITIATOR DETECTED ERROR message is sent from an initiator to inform a target that an error has
occurred that does not preclude the target from retrying the operation. The source of the error may either be
related to previous activities on the SCSI bus or may be internal to the initiator and unrelated to any previous
SCSI bus activity. Although present pointer integrity is not assured, a RESTORE POINTERS message or a
disconnect followed by a reconnect, shall cause the pointers to be restored to their defined prior state.
Linked Command Complete (0Ah)
The LINKED COMMAND COMPLETE message is sent from a target to an initiator to indicate that the execu-
tion of a linked command has completed and that status has been sent. The initiator shall then set the
pointers to the initial state for the next linked command.
Linked Command Complete (with Flag) (0Bh)
The LINKED COMMAND COMPLETE (WITH FLAG) message is sent from a target to an initiator to indicate
that the execution of a linked command (with the flag bit set to one) has completed and that status has been
sent. The initiator shall then set the pointers to the initial state of the next linked command.
Message Parity Error (09h)
The MESSAGE PARITY ERROR message is sent from the initiator to the target to indicate that the last
message byte it received had a parity error.
In order to indicate its intentions of sending this message, the initiator shall assert the ATN signal prior to its
release of the ACK signal for the REQ/ACK handshake of the message that has the parity error. This pro-
vides an interlock so that the target can determine which message has the parity error. If the target receives
this message under any other circumstance, it shall signal a catastrophic error condition by releasing the
BSY signal without any further information transfer attempt (see 3.1.1).