Command Processing

(1) HARD RESET

HARD RESET is used to abort all commands and to initialize the HDD to restore it to the same state as at the time of power-on.

After this reset operation, the UNIT ATTENTION condition with SCSI Reset Occurred [= 06-29-02] is generated for all the INITs.

(2) LOGICAL UNIT RESET

LOGICAL UNIT RESET TASK can be used to abort an L nexus command specified by an INIT and to initialize TARG to restore it to the same state as at the time of power-on. However, it must be noted that commands that have been issued by other initiators are also cleared in a multi-initiator environment.

After this task is performed, the unit attention condition for Target Reset Function Occurred [= 06-29-03] is generated for all the INITs.

(3) CLEAR TASK SET

CLEAR TASK SET is used to abort processing of the L nexus commands specified by an INIT. Environment settings and conditions, such as MODE SELECT parameters, that have been specified in advance are not changed.

After this task is performed, the unit attention condition for Command Cleared by Another INIT [= 06-2F-00] is generated for the INITs whose commands have been subject to abortion except for the INIT that has issued this task.

(4) ABORT TASK SET

ABORT TASK SET is used to abort the I-T-L nexus commands specified by an INIT.

(5) ABORT TASK

ABORT TASK is used to abort processing of the I-T-L-Q nexus command specified by an INIT.

Abort processing during write operation

In particular, if a command to write data to the disk medium which is currently being executed is cleared, the HDD aborts processing of that command as shown in Table 2.10. Stopping overlapped commands which are currently being executed (see 2.8.1) is accomplished by the same treatment. The INIT must investigate the command completion status, then if necessary, it must implement data recovery processing.

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Fujitsu MBA3073RC, MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC Hard Reset, ∙ Abort processing during write operation