Graduation date: 1992Control oriented local area networks (COLANs) are being installed in\ud factories at an increasing rate. Traditionally, process control has\ud operated with a master scheduler (computer) monitoring a number of points\ud in a control grid. As the complexity of today's process control needs\ud grow, the need to process information locally increases. Microcontrollers,\ud networked with a master scheduler, can collect data from a locus of points\ud and make decisions as to whether the master needs to be notified or not.\ud By processing data locally, memory and execution time are freed up for the\ud master scheduler. Task implementation becomes modular in nature,\ud resulting in process control software that is easier to write, and\ud maintain.\ud This structure is the basis for COLAN V, a low cost, real-time,\ud distributed control network developed at Oregon State University. COLAN\ud V was used as the foundation for the creation of a multi-media\ud presentation system. Six microcontrollers were networked together to\ud remotely control the operation of projectors, projector screens, and\ud lighting. Based on the application the master scheduler was replaced by\ud a tape player. This allowed the storage of the audio part of the\ud presentation on one track of the tape and the storage of the synchronized\ud control signals on the other track. This distributed control network\ud supplied a low cost solution to a need that was not addressed by the\ud commercial market at any price
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