Hitachi HUS154530VLF400 User Manual

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Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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21.6.6  Command Processing During Startup and Format Operations
If the Target receives a command from an Initiator while the Target is executing a startup or format operation, the response of 
the Target varies with the command as follows:
INQUIRY 
The drive sends inquiry data and returns appropriate status.
REQUEST SENSE 
Executes the command, returns a Sense key of NOT READY and an Additional Sense Code of 
LOGICAL UNIT NOT READY and returns GOOD STATUS.
The Additional Sense Code Qualifier that is returned depends on type of I/O processes that are 
active:
For the START/UNIT STOP and the Auto-start operation, the qualifier returned is LOGICAL 
UNIT IS IN PROCESS OF BECOMING READY. For the FORMAT UNIT command, the quali-
fier returned is LOGICAL UNIT NOT READY, FORMAT IN PROGRESS, and the Sense key spe-
cific bytes are set to return the progress indication.
REPORT LUNS
The drive sends REPORT LUNS data and approprate status. 
ALL OTHER 
The drive terminates the command with CHECK CONDITION status. The Sense data generated is 
described in Request Sense above.
21.6.7  Internal Error Condition
The Target generates an Internal Error condition for all Initiators when an internally initiated operation ends with an unrecov-
erable error, that is, the startup sequence for Auto Start enabled terminates after the SCSI bus has been enabled and prior to 
completion of the bring-up sequence.
An Internal Error condition causes Sense data to be generated and saved for all Initiators. The Error Code field of the Sense is 
set for a Current Error (70h) and the Sense Key is set to HARDWARE ERROR. Recovered errors are not reported.
The Internal Error condition persists for each Initiator until that Initiator clears the condition from the logical unit as described 
below. Several commands are handled as special cases during an Internal Error condition. These cases are also discussed. 
If the Target receives a command from an Initiator while an Internal Error condition exists for that Initiator, the response of the 
Target varies with the command as follows:
INQUIRY 
The drive executes the command with GOOD status and does not clear the Internal Error condition.
REQUEST SENSE 
The drive executes the command, returns the sense data generated by the Internal Error condition, 
returns Good Status, and clears the Internal Error condition for that Initiator.
ALL OTHER 
The drive terminates the command with a CHECK CONDITION status and clears the Internal 
Error condition.
21.6.8  Deferred Error Condition
Error code (71h) of sense data indicates that the Check Condition status returned is the result of an error or exception condition 
that occurred during execution of a previous command for which Good status has already been returned.
The drive creates an Deferred Error condition when
Execution of a Format Unit command with the immediate bit of one ends with an error.
Execution of a Write command with WCE (Write Cache Enable) bit of one ends with an error.