A satellite system for controlling real-time experiments

In this paper, we describe a computer system for controlling real-time psychology experiments. We begin by considering the kinds of experiments that are performed in our laboratory and examining the hardware and software requirements of these experiments. We then review various systems along a continuum ranging from general-purpose timesharing systems to stand-alone dedicated processors. The capabilities of these systems are described in comparison with our requirements. The features of the PARASITE-FS system are then described. This host-satellite system includes a local file system and monitor program, real-time device drivers with flexible interrupt processing capabilities, user-level routines for controlling the real-time devices, and a package for controlling the timing of experimental events.     

A microcomputer interface for control of real-time experiments in cognitive psychology

A microcomputer system for real-time control of experiments in cognitive psychology is described. The microcomputer serves as an interface that allows a remote timesharing computer to control the timed display of textual material on CRTs and collect response times accurate to 1 msec. It can control two CRT subject stations presenting the same or different experiments and control other devices such as slide projectors and tape recorders. It is argued that such special-purpose microcomputer interfaces provide a real-time laboratory with significantly less effort than does the more traditional laboratory minicomputer.     

A virtual terminal program for data transfer between a data general MicroNOVA laboratory computer and a DECsystem-10 timesharing system

A program for transferring data files between a small lab computer and a large timesharing system is described. The program is based on the concept of having the lab computer simulate a timesharing terminal. General features of the approach and the major implementation problems are discussed.     

Microcomputers in social psychophysiological research: An overview

Microcomputer systems have become commonplace in the psychophysiological laboratory during the past 5 years and are currently used in all phases of data acquisition, experimental control, and data analysis. In the past year, however, advances in microprocessor technology and scientific software have greatly extended the capabilities of these desk-top systems. Small laboratories now can afford an integrated laboratory microcomputer system and both the high-fidelity data acquisition hardware and the sophisticated analysis capabilities traditionally found in large minicomputers. We briefly describe the demands that social psychophysiological research can place on computer systems, the system presently employed in our laboratory, and a system being installed to overcome limitations on sampling rate, sampling periods, and waveform analysis.     

Hardware design style: The vital element

This is a tutorial in the application of digital integrated circuits to laboratory experimental design. For appropriate experiments, a hardware controller may be the most economical as well as the most enjoyable approach. By and large, the hardware profession has done a poor job of providing clear, straightforward principles of hardware design; therefore, the design process is often viewed as a “black art” accessible only to specialists. The computer software profession has begun to realize the vital need for systematic approaches to problem solving. We hope to contribute to a similar movement in the digital hardware design area.     

An intelligent experimental station controller for human experimental psychology

The purpose of this paper is to describe the intelligent experimental station controller used in the extensible multiprogramming system for experimental psychology (EMPP) at the University of Washington. The EMPP system is an integrated hardware and software system designed to simplify the development of on-line psychological experiments. An intelligent graphics control system is one of the most important aspects of the system. The controller oversees the operation of eight independent experimental stations, each containing a cathode ray tube (CRT) terminal and a keyboard console. In addition to conventional computer interface functions, the controller contains an extensible hardware character generator which allows dynamic selection of the display character set. This paper describes both the hardware and software features of the system.     

A method for utilizing a single port for multiple functions on the IBM PC or compatible system

Psychological experiments often require the control of a large number of output lines; unfortunately, the IBM PC provides only 32 8-bit ports through which communication may be implemented without risk of conflict with other software/hardware. A single 8-bit port may be used to control a large number of devices by adding appropriate decoder logic between the computer’s port and the devices that are to be controlled. Software and hardware are presented that illustrate this technique by controlling an 8-digit light-emitting diode display with a single IBM PC output port.     

Computer programming for generating visual stimuli

Critical to vision research is the generation of visual displays with precise control over stimulus metrics. Generating stimuli often requires adapting commercial software or developing specialized software for specific research applications. In order to facilitate this process, we give here an overview that allows nonexpert users to generate and customize stimuli for vision research. We first give a review of relevant hardware and software considerations, to allow the selection of display hardware, operating system, programming language, and graphics packages most appropriate for specific research applications. We then describe the framework of a generic computer program that can be adapted for use with a broad range of experimental applications. Stimuli are generated in the context of trial events, allowing the display of text messages, the monitoring of subject responses and reaction times, and the inclusion of contingency algorithms. This approach allows direct control and management of computer-generated visual stimuli while utilizing the full capabilities of modern hardware and software systems. The flowchart and source code for the stimulus-generating program may be downloaded from www.psychonomic.org/archive.     

The effect of computer response time on user performance and satisfaction: A preliminary investigation

The present study was designed to investigate the effect of delays in the response of the computer on the performance of the user and his satisfaction with the system. While it is generally assumed that computer responses should be no longer than several seconds, the present study showed no effect of 5- or 10-sec fixed or variable delays on subjects debugging a simple BASIC program. These results have important implications for the design of large, multiuser timesharing systems.     

Software timing of events in cognitive psychology experiments

Real-time systems for controlling cognitive psychology experiments typically use hardware clocks. However, systems using software clocks have comparable reliability, accuracy, and resolution, and the advantages of lower cost and hardware simplicity. Four types of software clocks are described and evaluated. Problems in implementing software clock systems are described, along with their solutions. Software clock routines for Apple II series microcomputers are presented.     

Linking large and small computers

A PDP-8/I was connected to an IBM/370 via telephone. Programs enable the PDP-8 to send data to practically any large-scale computer having timesharing capabilities. These programs can be used as models by others wishing to analyze data on a large computer.     

Maximizing the mini-uses of on-line computers

This paper draws on our experiences at Carnegie-Mellon University to provide a decision framework for the acquisition of computer systems for laboratory applications. Also recommended are ways of creating an effective operating environment that can handle changing needs. Systems developed for our most recent research in eye-movement recording and children’s concept learning using the Turtle will illustrate the design principles for hardware and software components of minicomputer systems.     

A real-time multiuser foreground,single-user background system for the PDP-9 computer

We have developed a software system for a PDP-9, with fixed head disk, to allow up to 16 remote laboratories to use the central PDP-9 facility for their experimental data acquisition and control needs. Timesharing is performed on a “demand” basis, using the hardware automatic priority-interrupt option. The real-time acquisition and control aspects are separated from the data reduction in the foreground by using a batch process foreground mainstream. The background is used primarily as a systems device for program updates and communications with a CDC terminal connected to a CDC 6600 computer. The philosophy, both software and hardware, developed for this heterogeneous user environment will be discussed.     

Using an Apple II microcomputer for real-time control in a behavioral laboratory

This report describes the hardware and software developed to implement an Apple II (48 KB) as a real-time control device for operant experiments. The hardware has a straightforward design, so that it is readily understandable and can be built by individuals with only minimal experience in the use of integrated circuits and other electronic components. The software routines listed below represent an approach to controlling and handling the data generated by an operant experiment. Using these routines, we are able to record each response and experimental event, the time of the occurrence, and the conditions at that time.     

NOVA SKED: A behavioral notation language for Data General minicomputers

A state notation language (NOVA SKED) for the experimental control and collection of data from operant behavior experiments by Data General NOVA series minicomputers is described. NOVA SKED is based on the SKED system written for the Digital Equipment Corporation PDP8 series of minicomputers. The NOVA SKED state notation syntax enables diagramming experimental procedures directly and precisely by the operant experimenter, who need not be familiar with computers. This syntax can then be compiled by the computer into programs that operate under the SKED run-time system (RTS). The SKED RTS operates in a timesharing mode that allows up to 16 experimental stations to function simultaneously and independently from each other. NOVA SKED is a “stand-alone” system that collects and stores data on digital magnetic tape.     

Zoroaster: A multiprogramming system for psychological research

The development of a multiprogramming system for psychological research was undertaken on a PDP-9 computer with 8k memory. The needs of the users and the time demands on the computer raised several important questions: (1) Can a practical timesharing system be developed with only 8k memory? (2) Can critical timing functions be maintained? (3) Can easy access be provided (e.g., Fortran) to all experimental devices? (4) Can a system be designed which will take advantage of and be compatible with most of the standard DEC-provided software (e.g., Fortran compiler, loader)? The system was successfully developed by using a rapid within-core swapping technique, standard I/O routines, many general-purpose handlers and subroutines, and fully utilizing available core.