Abstract: A video game or the like including a real-time interactive video disk game-play background generation system. The disk player incorporates track skipping capability which is under the direct control of the game processor, on a frame-by-frame basis, whereby substantially instantaneous jumps to alternative video scenes can be effected in response to changing game play. Video scene data is stored on the disk in horizontally compressed format. A video expander/scroller effectively stretches the compressed video from the disk by a factor of two and selects, under game processor control, one frame width, or one-half the expanded background scene, for display. A color programmable read-only-memory (PROM) having at least two pre-programmed color pallets is provided to redefine color relationships of game symbols stored in read-only-memory (ROM) thereby reducing the storage of redundant game symbol data in this ROM.

Abstract: A joystick actuator for controlling the positioning of objects, for instance, displays on CRTs, having a pivotally mounted control stick operatively engaging and driving a pair of optical-mask members. The optical-mask members are retained for rectilinear sliding motion relative to fixed mounted opto-switches and include spaced fins positioned to interrupt light communication within respective opto-switches. Positioning of the opto-switches and spacing of the mask fins are selected to provide successive unblocking of the interrupted light communication as the control column is displaced from neutral thereby encoding both the direction and magnitude of stick deflection.

Abstract: A microprocessor computer system includes random access and read only memories and a set of operator switches permitting the storage of game play information. During operation of the amusement device, game play is monitored and the score required to receive a free play is periodically adjusted to maintain a selected free play percentage. The percentage is determined by either the factory setting or the operator through the operator switches. The data used to compute the free play percentage is constantly checked by the system to insure that it is valid.

Abstract: A pinball machine having a plurality of inclined playfields is provided. The adjacent playfields are linked by at least one path allowing a ball to descend to the lower playfield and a path allowing a ball to be propelled by a player controlled flipper to the upper playfield.

Abstract: A video display system is provided for a video game or the like including a computer, a CRT, and mechanism for displaying images on the CRT under control of the computer. An image memory receives image data from the computer for subsequent display on the CRT. A mechanism causes the image data to be written into the image memory in one of two selectable modes, namely, left to right or right to left. Another mechanism causes the image data to be read from the memory for subsequent display on said CRT in one of two modes, namely, top to bottom or bottom to top. A mechanism controls the selection of the writing and reading modes wherein the image displayed on the CRT may be normal or inverted when viewed from a fixed position.

Abstract: Magnetic control of a ball on a pinball playfield is provided by an electromagnet located on the playfield and a mechanism manually operable by a player for energizing the electromagnet. The energizing mechanism includes a first switch external on the playfield operable by player and a second switch on the playfield which is activated by a ball hitting a target thereon. The first and second switch are connected in series with the electromagnet to control the latter. A timing mechanism is provided to limit the energization of the electromagnet to a predetermined time period.

Abstract: An electronic circuit is disclosed which is capable of producing synthesized sounds under the control of a microprocessor or other type computer. A plurality of switch inputs are provided whereby the sound to be produced can be selected. The processor, under program control, then generates such sounds utilizing one or more basic waveforms stored in a memory. These basic waveforms are modified in specified ways and then outputted through an I/O device to a digital to analog converter for application to an audio system. Eight input control lines to the microprocessor also feed an 8-input NAND gate, such that a momentary change of the normally-high control inputs will cause the NAND gate to activate an interrupt request.