FUJITSU MHT2060AT - Manual (Page 32)

Device Overview
1-12 C141-E192-01EN
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
1.11Advanced Power Management
The disk drive shifts to the three kinds of APM modes automatically under the
Idle condition.
The APM mode can be chosen with a Sector Count register of the
SETFEATURES(EF) command.
In APM Mode-1, which is the APM default mode, the operation status shifts till it
finally reaches "Low Power Idle."
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 : Reset APM (return to Default.)