The TMS 9918A VDP: A new device for generating moving displays on a microcomputer

A procedure for creating smooth and continuous moving displays on a microcomputer using the TMS 9918A video display processor (VDP) is discussed. This processor shares all of the features of other VDPs and, in addition, enables the user to directly program smooth motion of specified graphics shapes (sprites) with multilevel pattern overlaying. The general principles for programming this video chip are described, and a machine language driver is presented. Three illustrative applications from the event perception literature—wheel-generated motion, kinetic disruption of optical texture, and biomechanical motions—are presented as demonstrations of how the unique features of this video chip can be implemented in the creation of dynamic displays.