Status of the ATLAS control system upgrade

Certain components of the ATLAS control system are two generations behind today's technology. It has been decided to upgrade the control system. in part, by replacing Digital Equipment Corporation (DEC) PDP-11 computers with present-day VAX technology. Two primary goals have been defined for the upgraded control system. The first of these goals is to keep additional in-house'' written software to a minimum, while providing the portability necessary to ensure the continued use of existing software. In an attempt to achieve this goal, commercially-available software has been utilized to provide a foundation for the final control-system configuration. The second goal is to develop the new control system, while not interfering with accelerator operations. This paper describes some of the motivation for upgrading the ATLAS control system, the basic features of the new control system, and the present status of the system's development.