US Patent 7424059 Data transfer circuit

A transmission unit loads transmission data on a first register and outputs it to a transfer line and starts counting the transmission clock signals in a strobe generation counter according to a transmission clock signal. When the counted value reaches a set value, a strobe signal is output. A reception unit loads the transfer data onto a second register according to a reception clock signal. An edge detection unit generates a valid signal with a pulse width corresponding to one cycle of the reception clock signal when the strobe signal is detected. A third register loads the data that is output from the second register, and outputs it as reception data according to the reception clock signal when the valid signal is supplied.