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For the operation of the WASA (Wide Angle Shower Apparatus) detector system at the Cooler Synchrotron COSY in Forschungszentrum Julich (FZJ) a new DAQ system has been developed, which conforms to the third generation of the DAQ systems at COSY. This comprises new readout electronics based on an optimized parallel bus with LVDS technology and FPGA-controlled event and buffer management. The new DAQ system has been successfully commissioned in autumn 2006. Further developments aiming at performance optimizations are in progress. The implementation status is presented and performance issues are discussed.

Wide angle shower apparatus (WASA), a detector for charged and neutral particles is currently operated at the CELSIUS storage ring by TSL, Uppsala University. It shall be transferred to the Cooler Synchrotron (COSY) at Forschungszentrum Julich (FZJ) after the anticipated shutdown of CELSIUS in summer 2005. For operation in Julich a new DAQ system is being developed, which conforms to the third generation of the DAQ systems at COSY. This comprises new readout electronics based on an optimized parallel bus with LVDS technology and FPGA-controlled event and buffer management, a synchronization system and a high speed optical link to the readout computer. Architecture of the new DAQ system and the technical issues of subsystems are presented. Index Terms--Data acquisition, FPGA, optical communication, triggering.

During the upgrade of the small-angle neutron scattering instrument KWS-1 at the research reactor FRJ-2, the 15-yr-old detector system has been replaced. While the Anger camera-based concept of the detector remained unchanged, the signal and data processing branch has been completely revised. Because of higher count rate requirements, a highly configurable parallel readout electronics has been developed aiming at counting rates of several hundred kilohertz. The whole detector system has been recently installed at KWS-1 and measurements to study the system performance have been carried out. The linearity and spatial resolution of the new detector have been determined by an analysis of an acquired image taken with a hole diaphragm in front of the scintillator. The overall system dead time has been measured by comparing the detector count rates at several scattering intensities to the count rates achieved with a fission chamber. Finally, scattering patterns of well-known samples have been taken in order to demonstrate the quality of the acquired images. Index Terms--Anger camera, position-sensitive scintillation neutron detector.

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.

The ATM technology for highspeed serial transmission provides a new quality of communication by introducing novel features in a LAN environment, especially support of real time communication, of both LAN and WAN communication and of multimedia streams. In order to evaluate ATM for future DAQ systems and remote control systems as well as for a high speed picture archiving and communications system for medical images, Forschungszentrum Julich has build up a pilot system for the evaluation of ATM and standard low cost multimedia systems. It is a heterogeneous multivendor system containing a variety of switches and desktop solutions, employing different protocol options of ATM. The tests conducted in the pilot system revealed major difficulties regarding stability, interoperability and performance. The paper presents motivations, layout and results of the pilot system. Discussion of results concentrates on performance issues relevant for realistic applications, e.g. connection to a RAID system via NFS over ATM.

At the Julich Cooler Synchrotron, COSY, the magnetic spectrometer ANKE (Apparatus for Studies of Nucleon and Kaon Ejectils) is installed. Reaction products emitted by an internal target in the forward direction are measured. About 11,000 channels are read out. This requirement justified the design of a VLSI based readout system. For this, an analog chip (RAL 118) - a low power high speed eight channel amplifier and discriminator - is used. Digital delay, zero suppression and address encoding are performed by the digital chip RAL 111 from the Rutherford Appleton Laboratory. A scalable and flexible array of chamber mounted front end boards may be adapted to instrument detectors of any size. Readout is performed by serializing hit addresses over a high speed optical link to a CAMAC readout module which serves for additional data reduction, subevent building and a number of test functions. Furthermore, subevent data are transferred using a front panel ECLbus (FERAbus(*)) to a crate controller with PCI-interface. An industrial PC with diskless UNIX-compatible operating system (NetBSD) is responsible for controlling the CAMAC crate, processing the event data and connecting to a central event builder.

The Data Acquisition for experiments at the KFA Juelich COoler SYnchrotron COSY is based on VME, FASTBUS, CAMAC, VICbus, Ethernet and UNIX workstations. Controller and master, equipped with CPUs, VME CPUs and workstations are formed to a distributed processor system, in software arranged by the object oriented Experiment Message Specification (EMS) protocol according to the server client connectivity. To perform the control of various experiment arrangements, composed of different number of crates with many embedded modules, a Control System, running on workstations was developed. Configurable setup of the frontend, run control, and distribution and decoding of event data are involved in the system. Experiment customizing is performed by ASCII files in an easy manner. The software is structured by dedicated clients with OSF/Motif user interface and access to the configurable experiment database. The design and state of the control system will be presented.

Intelligent communication controllers for a layered protocol profile are a typical example of an embedded control application, where the classical approach for the software development is based on a proprietary real-time operating system kernel under which the individual layers are implemented as tasks. Based on the exemplary implementation of a derivative of MAP 3.0, an unusual and innovative approach is presented, where the protocol software is implemented under the UNIX-compatible real-time operating system LynxOS. The overall design of the embedded control application is presented under a more general view and economical implications as well as aspects of the development environment and performance are discussed.

For the KFA Julich 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 (IS09506), a powerful application layer protocol for distributed automation systems in industry. In our application servers are implemented on the mProcessor controller boards at the frontend. 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. We discuss the most important design decisions mainly focusing on the software aspects.

An intelligent CAMAC crate controller with a CC-A2 functionality and VICbus interface was designed to improve the CAMAC systems. The controller replaced the Branch Highway with the VICbus. It ushered in optional use of a Motorola 68030 microprocessor as CAMAC list-processor and optimization of CAMAC blocktransfers, optional Ethernet and Cheapernet connection. The controller system has been made commercially available.

PROFIBUS, being a national German (DIN 19245) and an European (EN 50170) standard, has become the most widely accepted modern fieldbus technology in Europe. It is expected to take a similar role on the world market, since the IEC standardisation efforts for a common international fieldbus failed recently. A major reason for its success is the technological and functional scalability based on a common core. Now, a wide range of PLCs as well as low cost process I/O is available (also from leading manufacturers like Siemens) which enable easy interfacing. ZEL, the central electronics facility of Forschungszentrum Julich, has decided to use predominantly industrial components (PLCs, I/Os, etc.) in the front end of slow control systems for physics experiments. Interfacing of these devices is accomplished by PROFIBUS controllers, that have been developed for PCI and CompactPCI with device drivers for Linux and LynxOS. Front end PROFIBUS controllers have been developed for integrating dedicated devices. On the base of two case studies -- a nuclear experiment and a neutron scattering experiment -- the paper describes this approach. Design of the PROFIBUS hardware and software as well as performance results are presented.

Based on thorough experiences with distributed experiment control systems and fieldbus applications we are developing a control system especially targeted at neutron scattering experiments. Main characteristic is that frontend equipment and control machine are coupled by the industrial fieldbus standard PROFIBUS (DIN 19245, EN 50170). This significantly reduces the amount of cabling necessary. Further, it provides the proven error recovery and diagnostic features of an industrial fieldbus to the experiment control area. Frontend equipment comprises industrially available components like SIEMENS 'ET200' peripheral devices, PLCs and encoders (Heidenhain). For cost-sensitive stepper motor control a low-end motor controller from University of Gottingen is being interfaced directly to PROFIBUS. Widely available SIEMENS-SMP equipment can be coupled by a PROFIBUS-SMP interface developed at our institute. The controlling master is an Intel PC running a diskless Linux version, equipped with a home-made PROFIBUS controller in CompactPCI formfactor. As software interface to control applications the TACO framework developed at ESRF is employed. 'Device servers' in terms of the TACO client-server architecture have been created, allowing access to the functions of the control system at different levels, from raw PROFIBUS accesses up to complete motor control with position encoder feedback.

A compact and flexible low noise control-and readout-system has been developed for a X-ray pnCCD operation. The pnCCD is a new type of CCD originally developed for applications in space for X-ray astronomy. It is designed to perform extremely fast, high resolution spectroscopy of photons in the soft X-ray and infrared region with high efficiency. All interesting parameters of the new readout system like pulse-sequencing and power-up and-down are completely controlled by a front-end system with the help of hardwired interpreters getting their programs from a supervising PC. For adaptation of other CCD devices and optimisation, these parameters can be changed interactively by the PC operator. Coupling of the front-end system to the computer is done via a fiber optic link with PCI bus-interface. A menu driven, interactive program system under Linux serves for generation of timing sequences, experiment setup, visualisation and data storage. The system allows an image repetition rate of up to 220 frames/s which is limited only by the pnCCD readout speed.