Abstract:
A processor can operate in different power modes. In an active power mode, the processor executes software. In response to receiving a halt indication from the software, hardware at the processor evaluates bus transactions for the processor. If the bus transactions meet a heuristic, hardware places a processor core in a lower power mode, such as a retention mode. Because the bus transactions are evaluated by hardware, rather than by software, and the software is not required to perform handshakes and other protocols to place the processor in the lower power mode, the processor is able to place the processor core into the lower power mode more quickly, thereby conserving power.
Abstract:
A system may comprise a plurality of processing units, and a control unit and monitoring unit interfacing with the processing units. The control unit may receive requests for transitioning the processing units to respective target power-states, and specify respective target HW power-states corresponding to the respective target power-states. The monitoring unit may monitor operating characteristics of the system, and determine based on operating characteristics whether to allow the processing units to transition to the respective target hardware (HW) power-states. The control unit may be configured to change the respective target HW power-state to a respective updated HW power-state for each processing units for which it is determined that transition to its respective target HW power-state should not be allowed. The control unit may also be configured to infer a common target HW power-state based on the respective target HW power-states of processing units of a subset of the plurality of processing units, when the processing units of the subset of the plurality of processing units share at least one resource domain.
Abstract:
A system and method for automatically adjusting the volume of an audio system to compensate for variations in ambient noise. The system includes a microphone for monitoring the ambient audio environment which includes output of the audio system plus environmental noise. The system also includes processing circuitry connected to the microphone. The processing circuitry varies the volume of the output of the audio system in proportion to changes in the environmental noise. The processing circuitry comprises the microphone, located to detect the ambient sound in the listening environment, an analog-to-digital converter connected to the output of the microphone, and a digital signal processor connected to the output of the analog-to-digital converter. The output signal of the DSP is an input to the volume control of the audio system.
Abstract:
A system may comprise a plurality of processing units, and a control unit and monitoring unit interfacing with the processing units. The control unit may receive requests for transitioning the processing units to respective target power-states, and specify respective target HW power-states corresponding to the respective target power-states. The monitoring unit may monitor operating characteristics of the system, and determine based on operating characteristics whether to allow the processing units to transition to the respective target hardware (HW) power-states. The control unit may be configured to change the respective target HW power-state to a respective updated HW power-state for each processing units for which it is determined that transition to its respective target HW power-state should not be allowed. The control unit may also be configured to infer a common target HW power-state based on the respective target HW power-states of processing units of a subset of the plurality of processing units, when the processing units of the subset of the plurality of processing units share at least one resource domain.
Abstract:
An integrated circuit is coupled to a communication link and to a separate signal line and includes programmable registers specifying communication link width and frequency. The integrated circuit responds to a change in the value of the signal line by changing the width and/or frequency of at least a portion of the communication link to the programmed value in response to a change in a logical value of the signal line, without the integrated circuit entering a reset state. The width and/or frequency may be changed during a POST routine or during system operation as part of a power management or other system function while maintaining its operational state.
Abstract:
Power management logic maintains memory in a computer system in the self refresh state during a power savings state in which power is removed from the memory controller. A memory control circuit, separate from the power management logic, controls the memory during other operational modes. The power management logic maintains the system memory in the self refresh state by driving memory control signal(s) at appropriate values during the power savings state.
Abstract:
The maximum performance state available to a processor in a computer system, in terms of operating frequency and/or voltage, changes according to thermal criteria. When the temperature increases above a predetermined threshold, the maximum performance state available is reduced. Multiple temperature thresholds may be utilized providing for a gradually reduced maximum performance state as temperature increases. When the temperature returns to a lower level, the maximum performance state available is increased. Changing the maximum available performance state according to temperature provides for more gradual reduction in performance as temperature increases, which results in higher average system performance as temperature increases. Thus, a more gradual reduction in performance is provided while still maintaining a high speed rating of the processor in more ideal conditions. In normal operating conditions, high processor performance is provided, while slightly reduced performance is provided in abnormal operating conditions.
Abstract:
A processor can operate in three different modes. In an active mode, a first voltage is provided to the processor, where the first voltage is sufficient to allow the processor to execute instructions. In a low-power mode, a retention voltage is provided to the processor. The processor consumes less power in the retention mode than in the active mode. In addition, the processor can operate in a third mode, where a voltage is provided to the processor sufficient to allow the processor to process cache messages, such as coherency messages, but not execute other normal operations or perform normal operations at a very low speed relative to their performance in the active mode.
Abstract:
A serial communication system includes an integrated circuit having a master serial interface; and a processor having a slave serial interface coupled to the master serial interface through a clock signal line and a data signal line. The slave serial interface is responsive to a read temperature command issued by the master serial interface to return a first temperature value associated with the processor.
Abstract:
Method and apparatus for automatically adjusting the brightness level of an LCD based on the ambient lighting conditions of the environment in which the LCD is being operated are disclosed. In a preferred embodiment, a photodetector located proximate the front of the LCD generates to brightness control circuitry signals indicative of ambient lighting conditions. These signals are correlated to predetermined automatic brightness control values for use in controlling the brightness level of the LCD. Once the ambient light signals have been used automatically to set the brightness level of the LCD, user-selection of a different brightness level, either higher or lower, will override the automatic brightness control setting. In an alternative embodiment, a first photodetector is located proximate the front of the LCD and a second photodetector is located proximate the back of the LCD. In this embodiment, the brighter ambient condition is used to control the brightness level of the LCD. In another alternative embodiment, the brightness control circuitry comprises some form of artificial intelligence for "learning" a user's preferred brightness level, or range of brightness levels, in various ambient lighting conditions.