US Patent 7502991 Redundant 3-wire communication system

A redundant communication system for providing data communication between a first computing node and a second computing node. A transmitter is provided as part of the first computing node. A receiver is provided as part of the second computing node. A first signal line carries a first data signal. The first signal line electrically couples the transmitter with the receiver. A second signal line carries a second data signal redundant to the first signal. The second signal line electrically couples the transmitter with the receiver. The receiver evaluates the first data signal to determine the presence of an error and the second node uses the second data signal if an error is detected in the first data signal.