Patent ID: 8805196

Claim:
A communications link for carrying data between a transmitter and a receiver according to a communications protocol specifying a reduced-power link operating state in which the transmitter generates a reduced-amplitude electrical output signal at an electrical output and the receiver is to operate in a power-save mode, the communications link comprising: an electro-optical link having an E/O converter for generating an optical signal from an electrical input signal at an electrical input, an optical transmission medium for carrying the optical signal, and an O/E converter for generating an electrical output signal from the optical signal, the electrical output signal provided to the receiver; and a circuit coupling the electrical output of the transmitter to the electrical input of the electro-optical link, the circuit being configured to (1) forward the electrical output signal of the transmitter to the electrical input of the electro-optical link during normal-power link operation, and (2) detect initiation of the reduced-power link operating state and, during the reduced-power link operating state, to periodically send Idle messages to the receiver via the electro-optical link to maintain a normal amplitude of the optical signal on the electro-optical link causing the receiver to maintain normal-power operation during the reduced-power link operating state.