first and second devices may simultaneously communicate bidirectionally with each other using only a single pair of lvds signal paths . each device includes an input circuit and a differential output driver connected to the single pair of lvds signal paths . an input to the input circuit is also connected to the input of the driver . the input circuit may also receive an offset voltage . in response to its inputs , the input circuit in each device can use comparators , gates and a multiplexer to determine the logic state being transmitted over the pair of lvds signal paths from the other device . this advantageously reduces the number of required interconnects between the first and second devices by one half .