The NBI control system for the TJ-II

A description of the control system software and hardware architecture for the TJ-II Neutral Beam Injectors is given. The platform chosen is VMEbus, with controller boards running OS9 (Microware) real-time operating system. Three VME crates house several boards for performing analogue signal acquisition, signal conditioning, analogue voltage generation, digital input detection and digital output generation. A specific timing system for the injectors has been developed. At present, a user interface for monitoring and programming purposes is provided by html pages, using a web server running under the OS9 operating system. A few subsystems are now using a graphical user interface built using the Java programming language.