Abstract: In one embodiment, a method for power management includes receiving one or more state signals, each of the one or more state signals indicating whether a respective sub-block of a memory controller is idle or active, and determining whether to place the memory controller in an idle state or an active state based on the one or more state signals. The method also includes eating pulses of an input clock signal to produce a reduced-frequency clock signal if a determination is made to place the memory controller in the idle state, wherein the reduced-frequency clock signal is output to the memory controller. The method further includes passing the input clock signal to the memory controller if a determination is made to place the memory controller in the active state.

Abstract: A system for communication on a chip. The system includes an on-chip communication bus including plural tracks, and a plurality of stations that couple a plurality of on-chip components to the on-chip communication bus, whereby the plurality of on-chip components use the tracks to communicate. Each station preferably includes an initiator that requests permission to transmit outgoing data over a track to another station and that transmits the outgoing data, an arbiter that evaluates requests from other stations and selects a track on which to receive incoming data, and a target that receives the incoming data. The initiator can be connected to a grant multiplexor for selecting a grant line, with the grant multiplexor further including plural smaller multiplexors distributed across the chip. Likewise, the arbiter can be connected to a track multiplexor for selecting a track, with the track multiplexor further including plural smaller multiplexors distributed across the chip.

Abstract: Method and system for determining varying widths of each of a sequence of signal components (marks and spaces) in an incoming digital signal stream and for indicating which mark widths and which space widths fall outside acceptable ranges. A pre-mark and pre-space are added to the front end of the recieved stream for alignment purposes. The width of each signal component (mark or space) is determined and compared with an acceptable range of mark widths or space widths. Each mark or space that lies outside an acceptable range has an indicium associated with this mark or space, indicating this non-compliance. The modified digital signal stream, including the indicia, is re-issued after a selected time delay for subsequent signal processing. A method for measurement or estimation of mark width and space width is presented.

Abstract: A method and apparatus for dynamic chaining of DMA operations that includes a count to keep track of control blocks associated with such operations when appended to a current chain of control blocks. The count is checked by a DMA controller upon completing the data-transfer operation associated with each block or each control-block chain depending on the use of a wait bit. Memory used to hold control blocks may be preallocated with anticipated control blocks associated in a predefined linked list to avoid the need for subsequently updating existing control blocks when new blocks are appended to a chain.