Fujitsu MAN3184 User Manual

C141-E124-01EN

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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]).

Group 7 command operation codes (X ‘E0’ 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.

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.

Also, if initialization of the disk media (formatting) has not been completed normally, it will be
impossible to access data on the disk media.

Processing of and response to commands received by the IDD when it is in the not ready state or in
the initialization incomplete state are described below.  Furthermore, starting control of the spindle
motor when the power is switched on can be selected from either or two methods, through the
setting terminal (motor start mode) on the IDD, with rotation started at the same time as when the
power is switched on or through the START/STOP UNIT command.