Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications page 131

• Read Reporting Threshold specifies the error reporting threshold for recovered data errors during read operations when
PER=1.
• Write Reporting Threshold specifies the error reporting threshold for recovered data errors during write operations
when PER=1.
• DRRT (Disable Restore Reassign Target) bit disables the reading and restoration of the target LBA during a Reassign
Blocks command. If the DRRT bit is zero, the reassign command attempts to restore the target LBA's data. If the data
cannot be restored, the target LBA is reassigned and written with a data pattern of all 00s. If the DRRT bit is one, no
attempt is made to restore the target LBA.
• FFMT (Fast Format Enable) bit allows the formatting of the drive without any writes to the customer media. All format
operations are allowed including changing block sizes and manipulating defects. The drive will operate normally
after a fast format with the following caveat: since no data is written to any customer data blocks as a result of a Fast
Format operation, there is a possibility that a read attempt to any particular block (without having previously written
to that block) will result in an unrecoverable data error. This will most likely happen if the block size is changed as
every LBA will contain data of an incorrect length and apparently an incorrect starting point. It is also possible to
generate an uncorrectable data error without changing block sizes if the defect list is shortened and previously bad
blocks become visible in the customer address space. Of course ALL DATA ON THE DRIVE WILL BE LOST as
the result of any format operation and so any attempt to read blocks which have not been written to will result in
unpredictable behavior.
• FCERT (Format Certification) bit determines whether the certification step will be performed during a Format Unit
command. FCERT bit set to 0 disables certification. FCERT bit set to 1 enables the certification step.
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
113