Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications page 81

Notes: It is recommended that the MODE SELECT command be issued prior to the FORMAT UNIT command to
specify parameters that affect the formatting process.
The Block Length parameter of the Mode Select Parameter List's Block Descriptor is used during formatting and is
saved following a successful format operation. If a MODE SELECT command has not been issued since the last reset
or start-up (bring-up) sequence, then the Block Length from the previous format operation is used.
Subsequent to receiving a FORMAT UNIT command, the Target responds to commands as follows:
- All commands except REQUEST SENSE and INQUIRY return Check Condition status, while the format operation
is an active I/O process.
- When tagged queuing is enabled (DQue = 0), all commands except REQUEST SENSE and INQUIRY return
Queue Full status, while the FORMAT UNIT command is a queued I/O process.
- When tagged queuing is disabled (DQue = 1), all commands except REQUEST SENSE and INQUIRY return Busy
status, while the FORMAT UNIT command is a queued I/O process
- If a REQUEST SENSE command is received while a format operation is an active I/O process, the Target returns
Good status. The sense key is set to Not Ready and the additional sense code and qualifier is set to Format In
Progress.
- If an INQUIRY command is received while a format operation is an active I/O process, the Target returns Good
status and Inquiry data as requested.
The format operation must complete successfully for the Drive to be usable. If the command is interrupted by a reset,
power down, or an unrecoverable error, the Drive enters a degraded mode of operation in which reading and writing
are prohibited. To exit the degraded mode, another FORMAT UNIT command must be sent by the Initiator and com-
pleted successfully by the Target.
The FORMAT UNIT command sets the Unit Attention Condition for all Initiators except the one that issued the FOR-
MAT UNIT command.
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
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