A Computer-Driven Full-Color Raster Scan Display System*

The system to be described, shown in Figure 1, employs raster scan "painting" to provide rich, flicker-free pictures. Color images are displayed at a resolution compatible with commercial television, while a high-resolution black and white display also exists for those cases where the standard resolution is inadequate. The mapping function, which is complex for this type of painting mode, is performed partially in the computer and partially in the display controller hardware. The controller and the magnetic disc perform automatic refreshing and handle the interfacing and data buffering functions. The computer used in the system is an IBM 1130 equipped with 8K of core, a disc, a card reader/punch, and a line printer. The computer services all user communications and provides system interactivity via the console keyboard. A set of FORTRAN-callable graphic subroutines is used in applications programs to generate images. The overall operation is as follows: 1. The computer generates the picture information and performs part of the mapping function. 2. The information is transferred to the controller, where the mapping to digital video is completed. The video is then put on the refresh disc. 3. The controller refreshes the displays by continuously reading out the digital video from the disc.