Digital Control of Bevatron External-Proton-Beam Transport Magnets

A computer-based digitally-structured, data acquisition and control system has been developed for on-line programmed control of external beam transport magnets at the Bevatron. The control algorithm achieves flexibility to accommodate all possible modes of Bevatron operation by separating the operating cycle of the accelerator into several zones. This method allows independent processing of Bevatron field within each zone, and the introduction of zone-related time-variable functions in each of the magnet currents. Evolution of the hardware is discussed and use of small computers is considered for each well-defined project, over a time-shared single large computer. The technique utilized to provide time-sharing of peripheral hardware between small computers is described. Pertinent details of methods used to reject noise in transmission of both analog and digital data are examined. Communication between digital systems and the human operator is discussed in terms of minimizing the number of operator responses required to establish a series of functions to be performed by the system.