Browse Prior Art Database

Method for Asserting Lowest Computer Power Level

IP.com Disclosure Number: IPCOM000123461D
Original Publication Date: 1998-Dec-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 1 page(s) / 63K

Publishing Venue

IBM

Related People

Kubik, J: AUTHOR [+3]

Abstract

Disclosed is a method for computer system power management software to determine what the computer's power level should be and then put it at that level.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Method for Asserting Lowest Computer Power Level

   Disclosed is a method for computer system power management
software to determine what the computer's power level should be and
then put it at that level.

   Modern computer hardware can support multiple power
levels.  It is often difficult for power management software to
determine what level a system can be transitioned to.  In many
cases, only the computer's devices know what power level is required
for them to operate as the computer user desires.  For instance, the
user may desire the system to use less power until he presses a key
on the keyboard.  Only the keyboard device driver knows at what power
level it can detect the key being pressed.  Also, a device may be
conducting some operation that the user may wish it to complete
before powering to a lower level.  For instance, a print job should
complete before the system goes to a "sleep" level.

   A solution supporting these requirements, involves a
simple, two step strategy for determining the system's power
requirements and transitioning it to the appropriate level.  The
first step is for the system power manager to query each device in an
orderly fashion as to what power level it requires to perform user
desired behavior.  By "orderly fashion", meaning an order which takes
into account the power dependencies which may exist between devices
in the same system.  For instance, a bus must be powered before any
of the devices attached to it.  How the device knows user desired
behavior is independent of this process.  The device must return the
lowest power level it can achieve while still maintaining desired
behavior.  This is normally an off level, unless the device...