CONTROL FOR COMPUTER WINDOWING DISPLAY

摘要

A windowing control for a video display includes a programmed controller (17), a video display (43) including a screen and a raster for scanning the screen, a first memory (30) having a first area for storing data to be displayed in a first window defined on the screen and a second area for storing data to be displayed in a second window on the screen and a second memory (39) for storing the addresses of the data to be displayed in the first and second windows and the transitions between the windows. The controller includes a processor (17) programmed to load data into the first and second memory means and a memory controller (36) for initiating the transfer of data from the first and second memory to a pixel multiplexer (40). The processor (17) is also programmed to load new address data into the second memory means for each complete raster scan so that the position of the data within the window has the appearance of horizontal (panning) or vertical (scrolling) movement.