A circuit, set forth by way of example and not limitation, includes a signal detector operative to detect two types of signals, where the two types of signals include a higher-frequency signal and a lower-frequency signal. The signal detector is operative to detect that a received input signal is one of the two types of signals. An output driver is operative to receive the input signal and to adjust conditioning performed on the input signal to create an output signal for transmission over a communication channel, where the adjustment is based on the detection by the signal detector.