R. Au

A multitasking, multisinked, multiprocessor data acquisition front end

A description is given of a generalized data-acquisition front-end system that is based on MC68020 processors running a commercial real-time kernel (pSOS) and is implemented primarily in a high-level language (C). This system has been attached to the back-end online computing system at NSCL by means of a high-performance Ethernet protocol. Data may be simultaneously sent to any number of back-end systems. Fixed fraction sampling along links to back-end computing is also supported. A nonprocedural program generator simplifies the development of experiment-specific code. >

Status of the NSCL 4 pi data acquisition system

A status report on the VME-Ethernet-VAX-based data acquisition system used with the 200-plus-element NSCL 4 pi detector is given. Included are the design of the system and a report on the level of implementation and current performance. Two hardware modules unique to the system are discussed. One is the fast decision module, a CAMAC module used as a programmable trigger, and the other is a VME module used to interface the VME to the LeCroy ECLine. >

Overview of the Data Acquisition System at NSCL

The integrated data acquisition/analysis system for nuclear experiments is described. The selection criteria for the multi-processor system is discussed and the current configuration and planned expansion is shown. Operational rates and limitations of this system are given for some typical experiments. An overview of the multi-tasking software and user interfaces is given.

Progress on the Data Acquisition System at NSCL

We report on the progress made in data acquisition software development. Specifically, a unique generalized data routing scheme has been developed which allows user online analysis programs to be safely integrated into the acquisition system without endangering data sent to event recording devices. We describe the structure of the system. Performance is discussed and throughput calculated from it. User experience with the system is also discussed. We show how this routing system may easily be adapted to loosely coupled multiprocessor systems.

Use of a Sigma-7 in a Nuclear Physics Laboratory

Advanced features of the Scientific Data Systems Sigma-7 computer are being used at the Michigan State University Cyclotron Laboratory to produce a system which meets all of the needs of the laboratory. The computer is capable of large off-line tasks such as distorted wave Born approximation calculations and large on-line jobs such as 16K channel pulse height analysis and particle identification. Several off-line jobs can be time-shared with safe real-time operation using a supervisor program called JANUS.

A fast intelligent data acquisition system

Abstract A fast intelligent multiprocessor data acquisition system is described here. The system based on the MC68010 using the VME bus can acquire data via the CAMAC dataway at transfer rates up to 800 Kbytes/s. The system has a user friendly interface which builds the required assembly code needing only the CAMAC FNAs used in the experiment. In addition the system can be easily modified using the standard MC68010 assembly language to handle most preprocessing requirements. The system design will also allow for future expansion to the 32 bit word and faster instruction time of the MC68020. This expansion will allow for transfer rates well over a Mbyte/s.

A transputer based parallel processing frontend data acquisition system

A new parallel processing front end for data acquisition has been designed and built at NSCL. This system, using inmost T800 transputers, is designed to add the capacity of realtime data filtering to the normal operations of NSCL frontends and improve overall performance. The initial system is designed for 5 transputers linked to a SUN host system via transputer links. A prototype system with one node is currently used as the data acquisition system for the NSCL 4[pi] detector. The multinode system has been installed and tested. Filter software is under development.

A network protocol for data acquisition at NSCL

A network protocol suited for data acquisition, designed and implemented by the authors, is described. The protocol is capable of sustained throughput of 400 Kbytes/s on Ethernet. The protocol has been embedded in a commercial intelligent Ethernet controller that provides a high-level interface to front-end systems in networked data acquisition systems. The discussion covers the protocol design goals, data transmission, link management performance, and the overall project status. >

CCD camera system for use with a streamer chamber

Abstract A system based on three charge-coupled-device (CCD) cameras is described here. It has been used to acquire images from a streamer chamber and consists of three identical subsystems, one for each camera. Each subsystem contains an optical lens, CCD camera head, camera controller, an interface between the CCD and a microprocessor, and a link to a minicomputer for data recording and on-line analysis. Image analysis techniques have been developed to enhance the quality of the particle tracks. Some steps have been made to automatically identify tracks and reconstruct the event.