Power Management Feature; Power Modes; Power Management Commands; Standby Timer - Hitachi ic35l060avv207-0 - Deskstar 60 GB Hard Drive Specifications

9.5 Power management feature

The power management feature set permits a host to reduce the power required to operate the drive. It
provides a set of commands and a timer that enable a device to implement low power consumption
modes.
The drive implements the following set of functions:

Standby timer

Idle command
Idle Immediate command
Sleep command
Standby command
Standby Immediate command

9.5.1 Power modes

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.
In Standby Mode the device interface is capable of accepting commands, but as the media may not be
immediately 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 executing a command or accessing the disk media with the read look-ahead
function or the write cache function.

9.5.2 Power management commands

The Check Power Mode command enables a host to determine if a device is currently in, going into, or
leaving standby mode.
The Idle and Idle Immediate commands move a device to idle mode directly from the active or standby
modes. The idle command also sets the standby timer count and starts the standby timer.
The Standby and Standby Immediate commands move a device to standby mode directly from the active
or idle modes. The standby command also sets the standby timer count.
The Sleep command moves a device to sleep mode. The interface of the device becomes inactive at the
completion of the sleep command. A reset is required to move a device out of sleep mode. When a
device exits sleep mode, it enters Standby mode.
9.5.3 Standby timer
The standby timer provides a method for the device to automatically enter standby mode from either
active or idle mode following a host programmed period of inactivity. If the device is in the active or idle
mode, the device waits for the specified time period and, if no command is received, the device automa-
tically enters the standby mode.
If the value of SECTOR COUNT register on Idle command or Standby command is set to 00h, the
standby timer is disabled.
Deskstar 180GXP hard disk drive specifications
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