The CESR Control System

Computer control of CESR, the Cornell (8 + 8)GeV e+e- colliding-beam facility, places special emphasis on response speed, operator convenience, and economy of programming effort. Individual subsystem computers (PDP-11/34@) run autonomously under standard operating systems. Each has its own high-speed data bus network through which it controls accelerator components and accepts operator commands. Message traffic between computers is restricted to links which give a central DECsystem-1070 direct memory access to each of the PDP-11s. The 1070 can control higher-level operations by using slave tasks running in the PDP-11s; it also makes its resources available for data storage and manipulation, editing of program source files (mostly FORTRAN), and preprocessing by the FLECS translator.