In a display for a process control system, the display can be generated by one of two different sources, but is controlled by only one of them. A process control system network provides a first source of display, while a windowing system provides a second source. The control system network provides crucial...http://www.google.com/patents/US5598521?utm_source=gb-gplus-sharePatent US5598521 - Directly connected display of process control system in an open systems windows environment
