Distributed power management system and method for computer

A power consumption management apparatus for use with an electronic system having a processor and a device coupled to said processor, said apparatus comprising:

• at least one circuit driven by a clock signal having a clock signal period within said device;
• a detector circuit for detecting an access request to said device;
• a clock control circuit for selectively providing a clock signal to said at least one clock driven circuit in response to detection of said access request and for withholding said clock signal in the absence of said detection;
• said clock control circuit configured to selectively provide and withhold said clock signal to said at least one clock driven circuit of said device within a predetermined number of clock periods;
• said clock driven circuit consuming substantially no power when said clock signal is withheld so that power consumption by said clock driven circuit and by said electronic system is reduced during periods of time during which no access request for said device have occurred.

In a computer system operating in a multi-tasking computing environment supporting time-multiplexed task execution and having a plurality of devices, and a communications link for broadcasting a device identifier to said plurality of devices, a system for managing power consumption by said devices comprising:

• a unique device identifier associated with each said device;
• a comparator for comparing said broadcast device identifier with each said unique device identifier to determine whether said broadcast device identifier matches any of said unique device identifiers;
• a control circuit for withholding a device operating input to any of said plurality of devices when said broadcast device identifier does not match said unique device identifier associated with said device and for providing said device operating input only to said devices only when said broadcast device identifier matches said unique device identifier associated with said device;
• said broadcast device identifier matching said unique device identifier only during a period of time during which said device associated with said unique device identifier is being accessed to execute one of said time-multiplexed tasks.

In an electronic system having a processor, a device, and a communications link supporting communications between said processor and said device, said system being operative to perform a plurality of substantially overlapping tasks in a multi-tasking environment wherein only one of said plurality of substantially overlapping tasks is actually executing during a particular segment of time;

• a method for managing power consumed by said system comprising:
• associating a unique device identifier with said device;
• broadcasting said unique device identifier over said communications link only when said device will actually be accessed by said electronic system in performing a particular task during said particular segment of time and irrespective of whether said particular task utilizing said device during said particular segment of time has been completed;
• and
• providing an operation enable signal required for operation of said device only when said broadcast unique device identifier is received by said device and otherwise withholding said operation enable signal from said device, receipt of said operation enable signal causing said device to transition from a non-operational power conservative state to an operational state wherein said device consumes more power than when in said non-operational state, only during said particular segment of time when said device is being accessed.

In a computer system having a plurality of devices, and a communications link for communicating a broadcast device identifier to said plurality of devices, said computer system operating to perform a plurality of overlapping tasks in a multi-tasking environment, a method for managing power consumption in said computer system comprising:

• associating a unique device identifier with each said device;
• monitoring communications over said communications link, by each said device, during a time period to determine broadcast device identifiers contained within said monitored communication;
• comparing said broadcast device identifier with said unique device identifier associated with each said device to determine whether said broadcast device identifiers match said unique device identifier for any of said devices;
• withholding a device operating input to ones of said plurality of devices when said broadcast device identifier does not match said unique device identifiers associated with said ones of said plurality of devices;
• and
• providing said device operating input to ones of said devices only when said broadcast device identifier matches said unique device identifier for said device;
• said computer system operating to perform a plurality of substantially simultaneous operations in a multi-tasking environment,
• broadcasting said unique device identifier only during a time period in which said device is actually being accessed by said computer system, independent of whether a particular processing task using said device associated with said unique device identifier during said time period has been completed;
• and
• providing said device operating input only to said device when said device is actually being accessed by said computer system.