Fujitsu 80, Scsi Logical Interface Specifications

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Command Processing
1-24 C141-C010
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.).
Notes:
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.
1.7.2 Illegal LUN specification
The logical unit number (LUN) supported by the IDD is LUN = 0 only. If a LUN other than this
(1 to 7) is specified, the IDD performs one of the following operations, depending on the type of
command issued at that time.
1) The INQUIRY command is executed normally even if the LUN specification is illegal. However,
byte 0 of the “Standard INQUIRY Data” (“Qualifier” field and “Device Type Code” field) transferred
to the INIT for that command indicates X ‘7F.’
2) The REQUEST SENSE command is executed normally even if the LUN specification is illegal.
However, the sense data transferred to the INIT for that command indicates that the LUN
specification is illegal (ILLEGAL REQUEST [=5]/Logical unit not supported [=25-00]).
3) If an illegal LUN is specified for a command other than the INQUIRY command or REQUEST
SENSE command, that command is terminated abnormally with a CHECK CONDITION status. The
sense data generated at this time indicate that the LUN specification is illegal (ILLEGAL REQUEST
[=5] /Logical unit not supported [=25-00]).
1.7.3 Reserved operation code
Group 6 and Group 7 commands operation codes (X ‘C0’ to X ‘FF’) are reserved by Fujitsu. When any
command is issued which includes these operation codes, the IDD does not always respond with a
CHECK CONDITION status (ILLEGAL REQUEST [=5] / Invalid command operation code [=20-00].
The INIT should not issue commands which contain these operation codes.
1.7.4 Command processing in the not ready state
After the IDD’s power is switched on, the initial self-diagnosis is completed normally and the spindle
motor reaches the normal rotational speed, “system information,” which includes such information as
MODE SELECT parameters and disk media defect information is read from the system space on the disk
drive and each type of control information is initialized. When this operation is completed, the IDD is in
a state where it can be used (ready state). Furthermore, the not ready state is defined as the IDD being in
either of the following states.
•
When the spindle motor has not reached the normal rotational speed.
•
When reading of system information is not completed, or reading failed.