Quantum LTO 4, Руководство пользователя

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SCSI Interface Overview Page 8
State or Phase Description
Arbitration Phase The drive does not detect nor react to parity errors on the SCSI bus while
arbitration is being performed.
Selection Phase The drive does not detect nor react to parity errors on the SCSI bus while
the drive is being selected.
Selection, Message Out
Phase (Identify Message) If the drive detects a parity error while the host is sending an Identify
message, the drive retries forever.
Reselection, Message In
Phase (Identify Message) If the drive is attempting to reconnect to the host and the host asserts ATN
because it detected an error, the drive:
Switches the host to the Message Out Phase.
Waits for the host to send a 09 (Parity Error Message)
The drive then performs the retry option by:
Switching the host to the Message In Phase.
Resending the Identify Message
Command Phase If the drive detects a parity error while the host is transferring a CDB, the
drive:
Switches the host to Message In phase
Sends Restore Data Pointers (03h) message
Switches the host to Command phase to retry the command.
If a parity error occurs on the retry the host:
Terminates the transfer.
Switches the host to the Status Phase and sends a Check Condition.
Switches the host to the Message In Phase and sends a Command
Complete.
Sets the Sense Key = B and ASC/ASCQ = 47-00 (SPI interface only).
Data In Phase If the host detects a parity error while data is being transferred from the
drive and asserts ATN, the drive:
Terminates the transfer of data.
Switches the host to the Message Out Phase.
Waits for the host to send a 05 (Host Detected Error).
Switches the host to the Status Phase and sends a Check Condition.
Switches the host to the Message In Phase and sends a Command
Complete.
Sets the Sense Key = B and ASC/ASCQ = 48-00 (SPI interface only).
Data Out Phase If the drive detects a parity error while the host is transferring data, the
drive:
Terminates the transfer of data.
Switches the host to the Status Phase and sends a Check Condition.
Switches the host to the Message In Phase and sends Command
Complete.
Sets the Sense Key = B and ASC/ASCQ = 47-00 (SPI interface only).
Status Phase If the host is in the Status phase and detects an error in the status byte
and asserts ATN, the drive:
Switches the host to the Message Out Phase and waits for the host to
send 05 (Initiator Detected Error).
Switches the host to the Status Phase and sends a Check Condition.
Target sends restore pointers and resends Status.
Message In Phase If the host is in the Message In Phase and detects an error on a message
bytes an asserts ATN, the drive:
Switches the host to the Message Out Phase.
Waits for the host to send 09 (Parity Error Message).
Switches the host to the Message In Phase and resends the message.
Message Out Phase If the host is in the Message Out Phase and sends a message bytes and
the drive detects a parity error, the drive retries forever.