Quantum ATL SuperLoader ATL, User Manual

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Chapter 2 Messages
Supported SCSI Messages
Quantum ATL SuperLoader Software Interface Guide 19
Linked Command
Complete, Flag
(0Bh)
2
This 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, is
complete and that status has been sent.
Message Parity
Error (09h)
2
This message is sent from the initiator to tell the SuperLoader that
the last message byte the SuperLoader passed on to the initiator
contained a parity error.
To indicate that it intends to send the message, the initiator sets the
ATN signal before it releases ACK for the REQ/ACK handshake of
the message that has the parity error. This provides an interlock so
that the target can determine which message has the parity error. If
the target receives this message under any other condition, it
proceeds directly to the BUS FREE state by releasing the BSY
signal, signifying a catastrophic error.
The target’s response to this message is to switch to the MESSAGE
IN phase and re-send from the beginning all the bytes of the
message that precipitated the MESSAGE PARITY ERROR
message.
Message Reject
(07h)
2
This message is sent from the initiator or target to indicate that the
last message received was inappropriate or has not been
implemented.
To indicate its intention to send this message, the initiator asserts
the ATN signal before it releases ACK for the REQ/ACK
handshake of the message that is to be rejected. MESSAGE REJECT
is issued in response to any message the SuperLoader considers to
be illegal or not supported. When sending to the initiator, the
SuperLoader does so before requesting any additional message
bytes.