The second generation of DAQ-systems at COSY

At the Julich Cooler Synchrotron COSY several experiments are running based on a modular, flexible system design in hardware and software. Future data acquisition experiments should use PC-technologies as far as possible. For the intelligent units initially passive backplanes with Single Bord Computers (SBCs) have been chosen as defined by the PCI Industrial Computer Manufacturing Group (PICMG). For future applications the CompactPCI is considered which combines the IBM PC electrical and software standards with the Eurocard mechanical standards. Connection of the front-end modular systems (CAMAC, VME, FASTBUS) is performed by transparent controllers with PCI compliant interfaces, already available on the market or home made developments. As far as operating systems are concerned UNIX like systems are used. An object oriented, client-server based Experiment Messaging System (EMS) establishes the communication on the application layer between the experiment control, the event builder and different front-end systems. The design criteria for the second generation DAQ-Systems, a first experiment layout, interconnectivity questions and necessary component developments will be described, as well as the problems we have found turning a PC into a diskless system. Important results of performance measurements concerning the DAQ requirements will be given.