Power Management Feature; Power Mode; Power Management Commands; Standby/Sleep Command Completion Timing - IBM DTNA-22160 - Travelstar 2.1 GB Hard Drive Specifications

10.4 Power Management Feature

The power management feature set permits a host to modify the behavior of a manner which reduces the
power required to operate. The power management feature set provides a set of commands and a timer that
enable a device to implement low power consumption modes.
DTNA-xxxxx implement the following set of functions.
1. A Standby timer
2. Idle command
3. Idle Immediate command
4. Sleep command
5. Standby command
6. Standby Immediate command

10.4.1 Power Mode

The lowest power consumption when the device is powered on occurs in Sleep Mode. When in sleep mode,
the device requires a reset to be activated. The time to respond could be as long as the power on reset time.
In Standby Mode the device interface is capable of accepting commands, but as the media may not imme-
diately accessible, there is a delay while waiting for the spindle to reach operating speed.
In Idle Mode the device is capable of responding immediately to media access requests.
In Active Mode the device is under executing a command or accessing the disk media with read look-ahead
function or write cache function.

10.4.2 Power Management Commands

The Check Power Mode command allows a host to determine if a device is currently in, going to or leaving
standby mode.
The Idle and Idle Immediate commands move a device to idle mode immediately from the active or standby
modes. The idle command also sets the standby timer count and starts the standby timer.
The sleep command moves a device to sleep mode. The device's interface becomes inactive at the com-
pletion of the sleep command. A reset is required to move a device out of sleep mode. When a device exits
sleep mode it will enter idle mode.
The Standby and Standby Immediate commands move a device to standby mode immediately from the
active or idle modes. The standby command also sets the standby timer count.

10.4.3 Standby/Sleep command completion timing

1. Confirm the completion of the cached write commands
2. Set I N T R Q (completion of the command)
3. Move heads to park position
4. Activate the spindle brake to stop the spindle motor
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O E M Specifications of DTNA-2xxxx 2.5 inch H D D