Multi-Device Knob Utility for LCLS at SLAC
D.Fairley, D.Rogind, G.R.White, H.Smith, M.Woodley, P.Chu, P.Krejcik, S.Chevtsov, M.Zelazny* (SLAC)
At SLAC (SLAC National Accelerator Laboratory) the CD (Controls Department) is developing a new Multi-Device Knob Utility based on the EPICS * (Experimental Physics and Industrial Control System) toolkit for controlling more or more PVs (Process Variables) in unison, or simultaneously, from a physical knob located in the control room, or from various software tools such as EDM (EPICS Extensible Display Manager) or a Swing slider in Java. A group of devices are hooked up to a knob, then the value written to the devices is a simple function of the value of the knob. This is used, most commonly, to create a bump in the electron beam for LCLS (Linac Coherent Light Source). Control system variables typically controlled are magnetic fields, phases, and timing offsets. This paper describes the technologies used to implement this utility.
* http://www.aps.anl.gov/epics
Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515.