DEVICE DEPENDENT LAYER OF WINDOWING SYSTEM FOR A PROCESS CONTROL SYSTEM DISPLAY

摘要

The display system of a process control system is enhanced by adding windowing capabilities. These windowing capabilities allow numerous windows to be displayed on the system display simultaneously. Since it is required that the network display coexist with the windowing system, several alterations and enhancements were required to ensure proper operation. These enhancements include interpretation of communication between the windowing system and the process control system display generator. Also, since the windowing system is capable of displaying information from many different applications,special considerations regarding the display generator's color map were made to insure the integrity of the network display. Furthermore, considerations were needed so the windowing system would recognize numerous keyboards and pointing devices used by the process control system.