Fujitsu MHY2120BH 用户手册

 

1-14 

C141-E262 

Emergency Unload other than 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 Unload cannot be executed. 
Therefore, the number of Emergency other than Unload is specified. 

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 

 

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)