Patent ID: 7420970
Filing Date: 2008-09-02
Classification: H04J

Abstract:
1. A read port for selectively coupling one of a plurality of inputs to an output, wherein said plurality of inputs includes the registers of a register bank, said read port comprising: a plurality of inputs; an output; a plurality of multiplexers for selectively coupling a selected input to said output; and a multiplexer control signal input for inputting a multiplexer control signal, said multiplexer control signal comprising a plurality of control parameters and controlling switching of said plurality of multiplexers; wherein said plurality of multiplexers are arranged in a plurality of layers, said plurality of layers being arranged between said plurality of inputs and said output, such that said selected input is operable to be coupled to said output via one of said plurality of multiplexers from each of said plurality of layers; and at least one of said plurality of layers is divided into portions, each portion comprising at least one of said plurality of multiplexers, and wherein each layer and each portion has at least one control parameter input, such that each of said portions is individually controlled by one of said control parameters, at least one of said control parameters controlling more than one multiplexer, and multiplexers in one of said portions of one of said layers can be switched without switching multiplexers in another of said portions of said one layer, wherein at least one of said portions comprises at least two of said plurality of multiplexers.