Abstract: An engine operation timing control includes a transducer producing pulses at predetermined different angular positions of the engine shaft, a speed counter connected to the transducer and periodically generating a multibit digital signal corresponding to the speed of the engine, a programmed read only memory device addressed by the speed counter providing a digital output identifying the transducer pulse appropriate to commence the operation at the existing speed, and counter means for periodically causing commencement of said operation in synchronism with respective ones of the transducer pulses, said memory device being connected to said counter means to vary the phase of said counter means relative to shaft position.

Abstract: An angular position signal generator includes a rotor and a stator each having an arrangement of salient magnetic poles. The poles on the rotor are all of the same polarity and are spaced at unequal angles around the axis of the rotor. The poles on the stator are identically arranged so that in at least one position of the rotor all the poles are aligned and in at least two other positions only some of the poles are aligned. As the rotor rotates, therefore, the flux flowing between the poles fluctuates and a winding in the flux path produces pulses of different magnitudes at these various positions of the rotor.