Plans for the LEP Control System

As part of the study of the LEP electron-positron storage ring, the influence of technological trends on control system design is being assessed. These include availability of cheap processing power and data storage at all levels, wide-band communication by optical fibres, new modular interfacing systems and software concepts. It is suggested that the LEP control system will be based on two principles : - location of real-time and signal-processing functions within the controlled equipment. Micro-processors will deal with sequencing, monitoring, program generation and the equipment will have to be designed appropriately from the outset to achieve the potential cost savings and improved flexibility. The equipment will be connected by serial lines to a global communications system, structured hierarchically, and performing no significant processing outside the system control computers. Control actions will be caused by messages rather than loading of individual words into registers. The paper describes how the above principles could be applied to LEP and mentions some of the practical difficulties.