A multi-purpose digital controller for the LEP RF system

The RF system for the initial phase of LEP consists of eight identical units. Each RF unit contains a large amount and diverse range of equipment. The control configuration within an RF unit is described and the main categories of control parameters summarized. A description of the digital control units 'equipment controllers' used for the interface to and the control of the elements making up the RF unit is given. The design is such that as far as possible the same hardware (and software) can be used for the control of all the various pieces of equipment. The hardware is based on the G64 bus standard widely used at CERN and most of the software is written in Pascal. The equipment controllers are also used for various tests on RF equipment and 22 have been installed in a complete prototype RF unit (Test String). The 176 required for LEP are at present being manufactured in outside industry