Sony SDX-1100V Series, Руководство пользователя

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5.SCSI Interface
5-10 SONY AIT-5 drive SDX-1100V series Ver.1.0
5.3.6.
INITIATOR DETECTED ERROR (05h)
This message is sent from an initiator to inform a target that an error (e.g.: parity error) has occurred that does not
prevent the target from re-trying the operation. At this point, present pointer integrity is not assured. A RESTORE
POINTERS message or a disconnect followed by a re-selection, will cause the pointers to be restored to their
previously defined state.
This message will not be sent by the drive, when the drive is acting as an initiator. When received as a target the
unit will enter the status phase reporting CHECK CONDITION with the sense key set to COMMAND ABORTED.
5.3.7.
ABORT (06h)
This message is sent from the initiator to the target to clear the present operation. All pending data and status from
the affected logical unit is cleared, and the target goes to the BUS FREE phase. This message can be sent to a
logical unit that is not currently performing an operation for the initiator.
A transaction which has not yet been acknowledged with a good Status byte will cause the transaction to be
aborted. If a transaction has already been acknowledged, the abort will force a Write of any pending data. The
device will proceed directly to BUS FREE state.
5.3.8.
MESSAGE REJECT (07h)
This message is sent from either the initiator or target to indicate that the last message it received was
inappropriate or has not been implemented.
In order to indicate its intentions of sending this message, the initiator asserts the ATN signal prior to its release of
ACK for the REQ ACK handshake of the message that is to be rejected. Message Reject is issued in response to
any messages which the unit considers to be illegal or not supported. The illegal message will cause the current
command to be aborted and the unit will enter the status phase reporting CHECK CONDITION with the sense key
set to COMMAND ABORTED.
When received as a target, if the unit was previously in Message In phase (i.e.: sending messages to the host)
then MESSAGE REJECT will cause the unit to go straight to the Status phase with a CHECK CONDITION status
and a sense key of COMMAND ABORTED. If the unit was not previously in Message In phase then MESSAGE
REJECT will be handled as an illegal message.
If the initiator sends MESSAGE REJECT message in response to the units DISCONNECT message, the unit will
disable disconnects for the rest of the nexus and continue.
5.3.9.
NO OPERATION (08h)
This message is sent by an initiator in response to a target’s request for a message when the initiator does not
currently have any other valid message to send. This message is accepted when the drive is acting as a target,
and may be sent when it is an initiator. When a NO-OP is received during any phase, the unit will continue as
though nothing had happened.
5.3.10.
MESSAGE PARITY ERROR (09h)
This message is sent from the initiator to the target to indicate that one or more bytes in the last message it
received had a parity error.
To indicate its intentions of sending this message, the initiator will send the ATN signal prior to its release of 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.
This message will not be sent by the drive, when the drive is acting as an initiator. When received as a target, the
unit will enter the Status phase reporting CHECK CONDITION with the sense key set to COMMAND ABORTED.