Device Overview
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 SET
FEATURES(EF) command.
In APM
The disk drive complies with the three kinds of APM modes that a command from the host is required.
FR = 05h | : Enable APM |
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SC = C0h - FEh : | Low Power Idle | |||
SC = 80h | - BFh : | Low Power Idle (Default) | ||
SC = 01h | - 7Fh : | Low Power Idle → Standby | ||
FR = 85h | : | Disable APM (Set |
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