Upgrade of the Photon Beamline Control System on the SRS

The SRS is a 2GeV synchrotron light source with 14 beamlines serving approximately 34 experimental stations. Control of the major elements of the beamlines (vacuum pumps, gauges, valves and radiation stops) is the responsibility of the main SRS Control System. As part of the long-term upgrade plan for the SRS Control System a large programme of work has been undertaken to modernize beamline control. This work included: development of Linux based PC front end computers to interface to the existing CAMAC I/O system, replacement of the user interface by graphical synoptic diagrams running on Windows NT PCs, development of an ActiveX control for parameter display/control and a cache server to reduce loading on the rest of the control system. This paper describes the major components of the project; the techniques used to manage the new PCs and discusses some of the problems encountered during development.