A dynamically adjustable communication system and method automatically adjust transmission rates of discontinuous waveforms from one signal level to another for the purpose of optimizing a quality parameter of a transmitted signal. Circuitry coupled to the transmission medium provides feedback to transmitter circuitry for the purpose of adjusting at least one of a rise time and a fall time parameter of a transmitted signal for the purpose of enhancing transmission quality. Transmission rate can also be automatically adjusted to maximize data rate and minimize errors.