Fujitsu MBA3300RC Benutzerhandbuch

 

C141-C013 

111 

The RESERVE, RELEASE, RESERVE EXTENDED, and RELEASE 
EXTENDED commands should be issued with the specification of ORDERED 
QUEUE.  If any of these commands is issued with the specification of HEAD OF 
QUEUE, the command may cause the duplicated reserved status with a command 
that has been issued before. 

Since the TEST UNIT READY and INQUIRY commands do not affect the HDD 
status, they can be issued with the specification of HEAD OF QUEUE. 

An INIT can specify error recovery options with the QErr bits of the control mode 
parameter (Page A) of the Mode Select parameters.  Deferred errors may be 
reported for commands whose processing has already ended.  Therefore, the 
queue tag values assigned to those commands are not reported. 

Use ABORT TASK, ABORT TASK SET, CLEAR TASK SET, or LOGICAL 
UNIT RESET to clear some or all of the queued commands. 

The Unit Attention condition is a function for notifying the INIT asynchronously 
of events (status changes) which occur in the TARG or logical unit. 

Events which cause the Unit Attention condition to be generated are any of the 
following events. 

(1)  When a Power On or RESET occurs 

If the HDD is reset by a power on, HARD RESET, or LOGICAL UNIT RESET, 
regardless of whether the disk drive is in the ready state or not, the Unit Attention 
condition is generated to all the INITs. 

(2)  When I-T Nexus Loss occurs  

When I-T Nexus Loss has been detected and command processing of an INIT that 
has detected the I-T Nexus Loss is aborted, the Unit Attention condition is 
generated for the INIT. 

(3)  When drive parameters are changed (if changed by another INIT)  

If any of the following parameters is changed from an INIT, the Unit Attention 
condition is generated for all the INITs except the one that changes that 
parameter: 

• 

A parameter specified by the MODE SELECT or MODE SELECT 
EXTENDED command 

• 

A parameter specified by the SET DEVICE IDENTIFIER command