Write Safety; Data Buffer Test; Error Recovery; Automatic Reallocation - Hitachi HTS541616J9AT00 - Travelstar 160 GB Hard Drive Specifications

5.4

WRITE safety

The drive ensures that the data is written into the disk media properly. The following conditions are monitored
during a write operation. When one of these conditions exceeds the criteria, the write operation is terminated and the
automatic retry sequence is invoked.
Head off track
External shock
Low supply voltage
Spindle speed out of tolerance
Head open/short
5.5

Data buffer test

The data buffer is tested at power on reset and when a drive self-test is requested by the host. The test consists of a
write/read '00'x and 'ff'x pattern on all buffers.
5.6

Error recovery

Errors occurring on the drive are handled by the error recovery procedure.
Errors that are uncorrectable after application of the error recovery procedure are reported to the host system as
nonrecoverable errors.
5.7

Automatic reallocation

The sectors that show some errors may be reallocated automatically when specific conditions are met. The drive
does not report any auto reallocation to the host system. The conditions for auto reallocation are described below.
5.7.1 Nonrecovered write errors
When a write operation cannot be completed after the Error Recovery Procedure (ERP) is fully carried out, the
sectors are reallocated to the spare location. An error is reported to the host system only when the write cache is
disabled and the auto reallocation has failed.
5.7.2 Nonrecoverable read error
When a read operation fails after ERP is fully carried out, a hard error is reported to the host system. This location is
registered internally as a candidate for the reallocation. When a registered location is specified as a target of a write
operation, a sequence of media verification is performed automatically. When the result of this verification meets
the required criteria, this sector is reallocated.
5.7.3 Recovered read errors
When a read operation for a sector fails and is recovered at the specific ERP step, the sector is reallocated
automatically. A media verification sequence may be run prior to the reallocation according to the predefined
conditions.
Travelstar 5K160 (PATA) Hard Disk Drive Specification
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