Write Safety; Data Buffer Test; Error Recovery; Automatic Reallocation - IBM DTCA-23240 - Travelstar 3.2 GB Hard Drive Specifications

4.4 WRITE Safety

The drive ensures that the data is written into the disk media properly. Following conditions are monitored
during a write operation. When one of those conditions exceeds the criteria, the write operation is terminated
and automatic retry sequence will be invoked.
Head off track
External shock
Low supply voltage
Spindle speed tolerance

4.5 Data buffer test

The data buffer is tested at Power-on-reset and when a drive self-test is requested by the host. The tests are
consisted of write/read '00'x and 'ff'x pattern on all buffer.

4.6 Error Recovery

Errors occurring on the drive are handled by the error recovery procedure.
Errors that are uncorrectable after application of the error recovery procedures are reported to the host
system as non-recoverable errors.

4.7 Automatic Reallocation

The sectors those show some errors may be reallocated automatically when specific conditions are met. The
spare sectors for reallocation are located at the end of drive. As a result of reallocation, the physical location
of logically sequenced sectors will be dispersed. The drive does not report for auto-reallocation to the host
system. The conditions for auto-reallocation are described below.

4.7.1 Non Recovered Write Errors

When a write operation can not be completed after the Error Recovery Procedure (ERP) is fully carried out,
the sector(s) 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 is failed.

4.7.2 Non Recovered Read Errors

When a read operation is failed after defined E R P 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 criteria, this sector is reallocated.
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O E M Specifications of DTCA-2xxxx 2.5 inch H D D