Abstract: A method for power management is disclosed. The method may include monitoring requests for access to a memory of a memory subsystem by one or more processor cores; and monitoring requests for access to the memory conveyed by an input/output (I/O) unit. The method may further include determining if at least a first amount of time has elapsed since any one of the processor cores has asserted a memory access request and determining if at least a second amount of time has elapsed since the I/O unit has conveyed a memory access request. A first signal may be asserted if the first and second amounts of time have elapsed. A memory subsystem may be transitioned from operating in a full power state to a first low power state responsive to assertion of the first signal.

Abstract: A method for power management is disclosed. The method may include monitoring requests for access to a memory of a memory subsystem by one or more processor cores; and monitoring requests for access to the memory conveyed by an input/output (I/O) unit. The method may further include determining if at least a first amount of time has elapsed since any one of the processor cores has asserted a memory access request and determining if at least a second amount of time has elapsed since the I/O unit has conveyed a memory access request. A first signal may be asserted if the first and second amounts of time have elapsed. A memory subsystem may be transitioned from operating in a full power state to a first low power state responsive to assertion of the first signal.

Abstract: According to the present disclosure, a transmitter for transmitting control characters to a display device over an interface includes a transmitter portion configured to transmit a control character having a plurality of bit values to the display device. The transmitter also includes logic configured to determine values of the bits in the control character and construct a corresponding plurality of rebalancing control characters based on the determination of the values of the plurality of bits in the control character to have bit values selected such that the combination of the control character and rebalancing control character is DC balanced. As such, the transmitter provides DC balance correction to non-DC balanced control characters in such a way as to allow DVI and HDMI to operate properly on an AC-coupled connection.

Abstract: A configurable bus interface circuit includes an internal bus bridge and an internal circuit. The configurable bus interface circuit also includes an internal I/O circuit couplable to an external circuit, via the internal bus bridge. The configurable bus interface circuit electrically isolates the internal circuit to avoid the propagation of signals between the internal I/O circuit and the external circuit.

Abstract: A method and apparatus for performing scaling functions on a video signal is presented, where the scaling functions include a change in data rate of the signal. This is accomplished by performing the data rate conversion within a horizontal scaler of a video decoder. Filtering operations in the horizontal scaler are adjusted in order to take advantage of the data rate differential. Qualifier signals accompany portions of the video signal to indicate whether or not a particular portion of the signal is valid. These qualifiers are interpreted within the circuit to identify the portions that should be dropped, and the portions to be included in the output signal. In addition, registers within the horizontal scaler are used to store data corresponding to blanking regions within the input video signal, where data included in these blanking regions must be passed to the output signal in its entirety.