Fujitsu M2488, Руководство по эксплуатации продукта

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SCSI MESSAGES M2488 PRODUCT GUIDE
3-10 CG00000-011503 REV. A April 1997
3-3 SCSI BUS STATUS
A status byte, Table 3-3, is sent from the target to the initiator during the STATUS phase at the termina-
tion of each command unless the command is cleared by:
An ABORT message,
A BUS DEVICE RESET message,
A “hard” RESET condition, or
An unexpected BUS FREE condition.
Table 3-4 describes the status byte codes:
3-3.1 Good Status
This status indicates the target has successfully completed the command.
3-3.2 Check Condition
Any error, exception, or abnormal condition that causes sense data to be set, causes a CHECK CON-
DITION status. The REQUEST SENSE command is issued following a CHECK CONDITION sta-
tus, to determine the nature of the condition.
3-3.3 Busy Status
The target is busy. This status is returned whenever a target is unable to accept a command from an
otherwise acceptable initiator. The normal initiator recovery action is to issue the command again at a
later time.
3-3.4 Intermediate Status
This status is returned for every command in a series of linked commands (except the last command),
unless an error, exception, or abnormal condition causes a CHECK CONDITION status or a RESER-
Table 3-3. Status Byte
BITS
BYTES 7 6 5 4 3 2 1 0
0
Reserved Status Byte Code Reserved
Table 3-4. Status Byte Code Bit Values
STATUS BYTE BITS
STATUS REPRESENTED
7 6 5 4 3 2 1 0
R R 0 0 0 0 0 R Good
R R 0 0 0 0 1 R Check condition
R R 0 0 0 1 0 R Condition met/good *
R R 0 0 1 0 0 R Busy
R R 0 1 0 0 0 R Intermediate/good
R R 0 1 0 1 0 R Intermediate condition met/good *
R R 0 1 1 0 0 R Reservation conflict
R R 1 0 0 0 1 R Command terminated *
R R 1 0 1 0 0 R Queue full *
All Other Codes Reserved
R- Reserved bit
*- Not supported by this controller