Fujitsu MHU2100AT Manual Do Utilizador

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Device Overview 
 
1-12 C141-E202-01EN 
Emergency Unload other than Normal Unload is performed when the power is 
shut down while the heads are still loaded on the disk. 
The product supports the Emergency Unload a minimum of 20,000 times. 
When the power is shut down, the controlled Normal Unload cannot be executed. 
Therefore, the number of Emergency other than Normal Unload is specified. 
Remark: 
We recommend cutting the power supply of the HDD for this device after the 
Head Unload operation completes. The recommended power supply cutting 
sequence for this device is as follows: 
1) Disk 
Flush 
Flush Cache command execution. 
2) Head 
Unload 
Standby Immediate command execution. 
3) Wait 
Status 
Checking whether bit 7 of the status register was set to '0'. 
(wait to complete STANDBY IMMEDIATE command) 
4)  HDD power supply cutting 
 
1.11  Advanced Power Management 
The disk drive automatically shifts to the power saving mode according to the 
setting of the APM mode under the idle condition. 
The APM mode can be chosen with a Sector Count register of the SET 
FEATURES(EF) command. 
The disk drive complies with the three kinds of APM modes that a command 
from the host is required. 
FR = 05h  :   Enable APM 
SC = C0h - FEh  : 
Mode-0 Active Idle 
 Low Power Idle 
SC = 80h - BFh  : 
Mode-1 Active Idle 
 Low Power Idle (Default) 
SC = 01h - 7Fh  : 
Mode-2 Active Idle 
 Low Power Idle 
 Standby 
FR = 85h  :   Disable APM (Set Mode-0) 
 
Active Idle: 
The head is in a position of extreme inner in disk 
medium. (VCM Lock) 
Low Power Idle: 
The head is unloaded from disk. 
The spindle motor rotates.