Fujitsu MHW2100BS Manuale Utente

 

Known defects, for which alternative blocks can be assigned, are not included in 
the error rate count below.  It is assumed that the data blocks to be accessed are 
evenly distributed on the disk media. 

(1)  Unrecoverable read error 

Read errors that cannot be recovered by maximum read retries of drive without 
user’s retry and ECC corrections shall occur no more than 1 time when reading 
data of 10

14

 bits. Read retries are executed according to the disk drive’s error 

recovery procedure, and include read retries accompanying head offset operations. 

(2) Positioning error 

Positioning (seek) errors that can be recovered by one retry shall occur no more 
than 10 times in 10

7

 seek operations. 

Defective sectors are replaced with alternates when the disk drive is formatted 
prior to shipment from the factory (low level format).  Thus, the hosts see a defect-
free device. 

Alternate sectors are automatically accessed by the disk drive.  The user need not 
be concerned with access to alternate sectors. 

The Load/Unload function is a mechanism that loads the head on the disk and 
unloads the head from the disk. 

The product supports a minimum of 600,000 Load/Unload cycles. 
Unload is a normal head unloading operation and the commands listed below are 
executed. 

• 

STANDBY command issued 

• 

STANDBY IMMEDIATE command issued 

• 

SLEEP command issued 

• 

IDLE IMMEDIATE command (with unload feature) issued 

• 

Power Mode shifted with APM or APS feature. 

• 

SLUMBER signal transferred 
(PMREQ_S signal is transferred from the host or the drive, and the host 
responds with PMACK signal.) 

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