A control system upgrade of the spear synchrotron and injector

The SPEAR electron synchrotron is an old and venerable facility with a history of great physics. When this storage ring was converted to serve as a full-time synchrotron light source, it was evident that the facility was due for an overhaul of its control system. Outdated hardware interfaces, custom operator interfaces, and the control computer itself were replaced with off-the-shelf distributed intelligent controllers and networked X-workstations. However, almost all applications and control functions were retained by simply rewriting the layer of software closest to each new device. The success of this upgrade prompted us to do a similar upgrade of our Injector system. Although the Injector was already running an X-windows based control system, it was non-networked and Q-bus based. By using the same Ethernet based controllers that were used at SPEAR, we were able to integrate the two systems into one that resembles the ''standard model'' for control systems, and at the same time preserve the applications software that has been developed over the years on both systems