Hitachi hard disk 0J11285 500 GB 2.5 " 8 MB 0J11285 Ficha De Dados

Z5K500 OEM Specifications 

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5.1

5.2

5.3

5.4

5   Data integrity 

Data loss on power off 

Data loss will not be caused by a power off during any operation except write operation. 
A power off during a write operation causes the loss of any received or resident data that has not 

been written onto disk media. 

A power off during a write operation might make a maximum of one sector of data unreadable. This 

state can be recovered by a rewrite operation. 

Write Cache 

When the write cache is enabled, write commands may complete before the actual disk write operation 
finishes. This means that a power off, even after the write command completion, could cause a loss of 
data that the hard disk drive has received but not yet written onto a disk. 

In order to prevent this data loss, confirm the completion of the actual write operation prior to the power 
off by issuing one of the following operation.   

Soft reset 
Hard reset 
Flush Cache command 
Standby command 
Standby Immediate command 
Sleep command 

Confirm the command’s completion. 

Equipment status 

The equipment status is available to the host system any time the hard disk drive is not ready to read, 
write, or seek. This status normally exists at the power-on time and will be maintained until the following 
conditions are satisfied: 

The access recalibration/tuning is complete. 
The spindle speed meets the requirements for reliable operation. 
The self-check of the hard disk drive is complete. 

The appropriate error status is made available to the host system if any of the following conditions occur 
after the hard disk drive has become ready: 

 The spindle speed lies outside the requirements for reliable operation. 
 The occurrence of a Write Fault condition.   

WRITE safety 

The hard disk drive ensures that data is written into 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