Method and apparatus for communicating on an electrical bus by generating a master logical signal on the electrical bus in the form of a pulse-width modulation signal. Generating a slave logical signal on the electrical bus in the form of a current signal. Reading the slave logical signal by sampling the magnitude of the current signal on the electrical bus, wherein magnitude of the current on the electrical bus is sampled at a point in the bit time when the voltage on the electrical bus has remained constant for a period longer than the shortest time that the voltage remains at any level during the bit time.