Datasheet

5.0 Data integrity

5.1 Data loss at power off

Power off during any operations except for write operation will not cause any data loss.

Power off during a write operation causes the loss of data received by the drive but not yet written

onto the disk media.

There is a possibility that power off during a write operation might make a maximum of 1 sector of

data unreadable. This state can be recovered by a rewrite operation.

5.2 Write cache

y When write cache is enabled, there is a possibility that the write command completes before the

actual disk write operation finishes. This means that there is a possibility that a power off event may

occur even after a full write command finishes. This means that it is possible that even after a write

command completion a power off might cause the loss of the data which the drive has received but

not yet written onto the disk.

y In order to prevent data loss, confirm the completion of the actual write operation prior to the power

off by issuing the Standby Immediate or Sleep command and confirming its completion.

y The default state of the write cache at power-on is "OFF."

5.3 Equipment status

Equipment status is available to the host system any time the drive is not ready to read, write, or seek.

This status normally exists at power-on time and will be maintained until the following conditions are

satisfied:

y Access recalibration/tuning is complete.

y Spindle speed meets requirements for reliable operation.

y Self-check of drive is complete.

Appropriate error status is made available to the host system if either of the following conditions occur

after the drive has once become ready:

y Spindle speed outside requirements for reliable operation.

y Occurrence of a Write Fault condition.

5.4 WRITE safety

The drive ensures that the data is written onto the disk media properly. The 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.

y Head off track

y External shock

y Low supply voltage

y Spindle speed tolerance

y Head open/short

Hard disk drive specification for DSCM-11000/-10512/-10340