Abstract: A graphic video display system including at least one graphic layer having sizable, positionable windows and programmable priority values the sprites having fixed priority values. Portions of graphic layer windows and sprites which overlap with a current horizontal scan line of a video display are written to a line buffer. Overlapping objects are resolved by writing portions of objects overlapping the current horizontal scan line to the line buffer in order of the priority values of the objects.

Abstract: A scanning apparatus for uniquely identifying an actuated key on a keyboard and an actuated location in a drawing tablet. The scanning apparatus includes independently actuatable switches associated with the keyboard. The scanning apparatus also includes vertical and horizontal conducting traces juxtaposed one to another and electrically connected to a horizontal and vertical resistive bar, respectively, associated with the drawing tablet. The switches and traces are energized under control of the apparatus such that portions of each can be actuated by a user resulting in the generation of unique analog signals indicative of the particular key and particular location upon the drawing tablet actuated by the user. These unique analog signals are converted to digital signals for further processing.

Abstract: An electronic educational video system apparatus for connection to a standard television receiver for teaching basic skills to a child through the use of animated graphic displays which serve to motivate the child to utilize the apparatus and enhance the child's learning. A microprocessor cooperates with digital memory, a video generator, a sound generator, and a voice synthesizer to generate a display of a pictorial representation upon the television receiver combined with a request associated with the pictorial representation directing the child to provide a proposed correct response. The child's correct response is compared to the actual correct response stored in the digital memory so that the particular pictorial representation associated with a particular request may become animated to provide an indication to the child of the correctness of the child's response. The child may provide his or her response through a plurality of interchangeable input devices.

Abstract: An electronic educational video system apparatus for connection to a standard television receiver for teaching basic skills to a child through the use of animated graphic displays which serve to motivate the child to utilize the apparatus and enhance the child's learning. A microprocessor cooperates with digital memory, a video generator, a sound generator, and a voice synthesizer to generate a display of a pictorial representation upon the television receiver combined with a request associated with the pictorial representation directing the child to provide a proposed correct response. The child's correct response is compared to the actual correct response stored in the digital memory so that the particular pictorial representation associated with a particular request may become animated to provide an indication to the child of the correctness of the child's response. The child may provide his or her response through a plurality of interchangeable input devices.