Fujitsu 600C manual Message types, COMMAND COMPLETE X00 MESSAGE IN phase target → initiator

Models: 600C

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4.6.2Message types

Messages provide information consisting of one or more bytes that are transferred in the MESSAGE IN and MESSAGE OUT phases. These messages are used to control the bus phase sequence.

The initiator creates an ATTENIION condition for the target, indicating that it has a message to be reported to the target Only then the target switches to the MESSAGE OUT phase to receive the message.

If the target has completed the SELECTION phase, it can execute the MESSAGE IN phase at any time to send the message to the initiator.

The messages that can be communicated with this scanner are listed on the following table.

 

Table 4-24

 

 

Code

Message

 

 

00

COMMAND COMPLETE

05

INIATIATOR DETECTED

 

ERROR

06

ABORT

 

 

07

MESSAGE REIECF

 

 

08

NO OPERATION

 

 

09

MESSAGE PARITY ERROR

 

 

0C

BUS DEVICE RESET

 

 

8O TO FF

IDENTIFY

 

 

4.6.2.1COMMAND COMPLETE (X'00'): MESSAGE IN phase (target initiator)

This message indicates that a command has been terminated and a valid status has been reported to the

initiator.

The target always reports the COMMAND COMPLETE message after the STATUS phase at the completion the input/output operation. (This requirement also applies if the COMMAND phase is not executed because command cannot be received.)

Upon receiving the COMMAND COMPLETE message, the initiator knows that a command has terminated.

After sending the COMMAND COMPLETE message, the target switches into the BUS FREE phase.

If the COMMAND COMPLETE message is rejected with the MESSAGE REJECT message, this scanner switches into the BUS FREE phase.

4.6.2.2INITIATOR DETECTED ERROR (X'05'): MESSAGE OUT phase (initiator target)

This message indicates that the initiator detected a retriable error and intends to request the target for retry.

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Fujitsu 600C manual Message types, COMMAND COMPLETE X00 MESSAGE IN phase target → initiator