Patent ID: 7593470

Claim:
A communication system comprising: a first processing circuit having a first transmitter to transmit a first clock signal, at least one second transmitter to transmit either a second clock signal or a respective data signal, a first switch circuit to select either the second clock signal or the respective data signal to be transmitted by the at least one second transmitter, and a comparator; and a second processing circuit having a first receiver to receive the first clock signal from the first transmitter, at least one second receiver to receive either the second clock signal or the respective data signal from the at least one second transmitter, a third transmitter to transmit the first clock signal or the second clock signal, and a second switch circuit to select the first clock signal or the second clock signal to be transmitted by the third transmitter; wherein the comparator compares a phase of the first clock signal received from the third transmitter at a first time with a phase of the second clock signal received from the third transmitter at a second time.