Abstract: A controller which can be set to operate a group of sprinkler control valves, which can be easily set and tested for proper automatic operation, and which can operate a sprinkler system in a variety of ways. The controller includes a clock, a series of dividers for dividing down the frequency of the clock, and a group of controls that can be operated to begin sprinking cycles at predetermined times and close the sprinking control valves after predetermined durations. A selector control can be utilized to effectively increase the frequency of the clock, as by bypassing a divider stage, to operate the system at a very rapid rate, which is useful in testing the system for automatic operation after it is set and for repetitive short duration sprinkling cycles. The controller has a cascade input that enables the beginning of a cycle of operation by an external signal, to permit repeated cycling of the system, and to synchronize a group of controllers.