Abstract: Apparatus for projecting selected images of a scene onto a screen, such as images of a golf course looking toward a green, and for projecting and moving a spot of light on the screen superimposed on the scene, such as to represent the travel of a hit golf ball toward the green in the scene, provides both a scene projector and a light spot projector secured in fixed relationship in the same housing and provides dedicated control circuitry for controlling the apparatus in response to instruction signals received from outside the apparatus. The spot projector includes two rotatable mirrors controlled by two stepper motors to control the movement of the spot on the screen. Special circuitry is provided to generate control signal pulses for the stepper motors using a combination of a count signal pulse and a synchronizing pulse. Compensation for nonlinearities in the stepper motors may be provided by reference to a correlation table stored in memory.

Abstract: Sport simulation equipment, such as a equipment for simulating a game of golf, and made up of a plurality of components, each component adapted to carry out a function of the system in coordination with other components, and a control circuit for directing and coordinating operation of the system components, incorporates a communication system whereby each component may be connected to a transmission line and can send and receive information regarding coordination and operation of components. Each component includes a communication interface circuit which is connected between the component and the transmission line to send and receive information via the transmission line. The control circuit include a similar communication interface means connected to the transmission line. In a preferred embodiment of the invention, communication is initiated by a request in a predefined format addressed to a component to which the component responds in a predefined format.