Flexible data acquisition system for experiments at COSY

For the KFA Juelich COoler SYnchrotron (COSY) a general data acquisition system was developed. Its architecture is based on available standards (VME, FASTBUS, CAMAC, VICbus) and UNIX Workstations forming a distributed processor system. Based on this hardware a flexible and modular data acquisition software was designed allowing the configuration of various experiment arrangements. The software design for run control is arranged according to a client server connectivity model as well as to an object oriented structure. It is logically based on MAP/MMS (ISO9506), a powerful application layer protocol for distributed automation systems in industry. In this application servers are implemented on the mProcessor controller boards at the front end. On the workstation side the experiment control client consists of dedicated processes with access to the configurable experiment data base. The user interface is realized by OSF/Motif. Established software standards for online data analysis high energy physics are employed. The authors discuss the most important design decisions mainly focusing on the software aspects