Method and apparatus for adaptable phase training of high frequency clock signaling for data capture

Abstract

A method and apparatus for adaptable phase training of high frequency clock signaling for data capture is provided. A state machine synchronizes a first selection signal to a delay multiplexer and a second selection signal to a digital block demultiplexer to sequentially select a targeted pair of the static storage elements for each of a plurality of phase-delayed data strobe clock signals. Read back data from an external memory captured by the static storage elements is compared to known valid data. The state machine determines which of the plurality of phase-delayed data strobe clock signals resulted in known valid data being captured by the static storage elements based on the comparison. The state machine selects one of the plurality of phase-delayed data strobe clock signals that resulted in valid data being captured as a read clock signal for a memory controller to capture subsequent read data from the external memory.