Methods for generating a design for logic circuitry using rotary traveling wave oscillators are described. The control system includes an ECU. The device and method also allow the physiological constraints on the pump to be accounted for, preventing suction and minimizing back flow of the body fluid. In other embodiments, the cassette includes sensor leads for sensing of various properties of a dialysate. The other devices are operable to update locally stored quality of service parameters in response to detecting a change in the change indicator.