Fujitsu MAN3735 Manuale Utente

C141-E124-01EN

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If the following state occurs, the IDD recognizes that overlapping commands have been generated
and the command is terminated abnormally.

1) During the IDD is executing or queuing an untagged command, the INIT that issued that

command before the completion of the command execution issues either an untagged
command or a tagged command.

2) If the IDD is executing or queuing a tagged command, the INIT that issued that command

before the completion of the command execution issues another tagged command with the
same tag specified as the previous command or an untagged command.

Normally, completion of a command execution is at the point when the TARG notifies the INIT of
the TASK COMPLETE message.  Execution of a command can also be terminated by the RESET
condition, a TARGET RESET message, CLEAR TASK SET message, ABORT TASK SET
message or ABORT TASK message.

The IDD abnormally terminates all the commands (commands being executed or queued) received
from an INIT which is overlapping commands and the command that generated the overlap
condition by the procedure described below.

1) If the command received form the INIT is being executed, the IDD stops execution of the

command.  If the command is still in the queue and execution has not been started, the IDD
clears that command.

2) The IDD reports a CHECK CONDITION status for a command that generates an overlap.  At

this time, the sense data generated by the IDD indicates ABORTED COMMAND
[=B]/Overlapped commands attempted [=4E-00], or Tagged Overlapped [=4D-nn] (nn: tag
No.).

1)

In order for the INIT to stop processing of a command during a disconnect, it is
permitted to send an ABORT TASK message, ABORT TASK SET message,
CLEAR TASK SET message or TARGET RESET message with specifying the
logical unit (see Section 1.7.6).

2)

Specification of overlapping commands applies without dependence upon the type of
command that is issued second.  For example, even if the command issued second is
the INQUIRY or REQUEST SENSE command, the IDD reports the CHECK
CONDITION status and terminates both the first command and the second command
abnormally.