METHOD AND APPARATUS FOR EFFICIENT MEMORY-READ OPERATIONS WITH A VGA-COMPLIANT VIDEO DISPLAY ADAPTOR

摘要

PURPOSE: A method and apparatus for efficient memory-read operations with a VGA(Video Graphics Array) compliant video display adaptor is provided to improve an efficiency of reading information. CONSTITUTION: The efficiency of reading information from a video RAM (106) in a display adaptor (8) such as a VGA-compliant adaptor is improved by providing the desired information from a latch (102) whenever possible rather than reading the desired information from the video RAM (106) or cache memory. Routine operations with graphical user interfaces such as moving and resizing visual images can be improved by first reading information for all pixels stored in a given location stored in the video RAM (106) before executing any commands that modify the contents of that location.