Tachistoscopic timing on the TRS-80

A hardware/software system is described that enables the TRS-80 Model I microcomputer to be used as a tachistoscope. The system synchronizes stimulus presentation with the 16.7-msec scanning rate of the cathode-ray tube. Hardware and software configurations for reaction timing and stimulus presentation are presented and discussed.     

Accurate reaction time research with the TRS-80 microcomputer

Procedures for reaction time research with 1-msec accuracy are described using the video display of the TRS-80 microcomputer. The LVB Corporation interface is also employed. Use of the cassette recorder as a voice key in this research is illustrated. A sample assembly language program is presented.     

A large-scale expandable I/O port interface for the TRS-80 microcomputer

Described is a large-scale expandable input/output port interface for the Tandy Corporation TRS-80 microcomputer.     

Measuring reaction time with millisecond accuracy using the TRS-80 microcomputer

A machine language subroutine is proposed for measuring reaction time with millisecond accuracy using the TRS-80 microcomputer. This timer is accurate to 1 msec in the first 30,000 msec and to 5 msec in the first 65,000 msec (1 part in 10,000).     

A microcomputer-based plotter system for the TRS-80 and HP 7225

A software package, MICROPLOT, was developed to run on a TRS-80 Model I microcomputer in conjunction with the Hewlett-Packard (HP) 7226 or similiar HP plotter. Capabilities include XY plotting of up to 10 data sets and curve plotting of an nth-degree polynomial. The package operates under the NEWDOS 80 Version 2.0 disk operating system but, with appropriate modification, can be run under any operating system that has dynamic program line merge and delete functions in BASIC. This report describes the structure of the system, hardware configuration, plotting capabilities, and applications in the behavioral laboratory.     

A laboratory in experimental psychology using the TRS-80

Twenty-three BASIC language programs have been written to allow the TRS-80 and other microcomputers to perform most of the classical experiments normally used in teaching a laboratory course in experimental psychology. Most programs allow experiments to be run as though the computer was the specialized apparatus normally used. This facilitates a realistic and interactive learning experience for the students.     

Screen control and timing routines for the IBM microcomputer family using a high-level language

Procedures are described for the IBM PC/AT and compatibles that measure an event’s duration with millisecond accuracy and that synchronize stimulus presentation with the vertical-retrace signal. The software is written in Turbo Pascal (Versions 2.0, 3.0, and 4.0; Borland International, Inc., 1984, 1985, 1987). Difficulties reflecting differences among video controller cards are also presented.     

Using the TRS-80 cassette tape recorder as a voice key

A simple BASIC language program allows the standard TRS-80 tape recorder to function as a voice key to control the timing or running of an experiment.     

Software synchronizing of video displays and Z-80 processing in the Model III TRS-80

A machine language technique is described whereby the Z-80 microprocessor of the Model III TRS-80 can be programmed to monitor position of the electron beam during CRT scanning. This technique provides the opportunity to synchronize the appearance of video displays with Z-80 processing. The programmer can therefore be assured of crisp stimulus displays and precisely recorded reaction times. The computer’s real-time clock operates on video circuitry as part of a routine that is initiated by a maskable interrupt. The real-time clock interrupt can be vectored from its normal use to a routine that signals the Z-80 when the electron beam is at a known screen location. A machine language program and a TRSDOS BASIC program that demonstrate the technique are described.     

Turbo Pascal timing routines for the IBM microcomputer family

Two Turbo Pascal (versions 3.0 and 4.0) software timers for the IBM microcomputer family are described: one with a 55-msec resolution and another with a 1-msec resolution. Both can be implemented without additional hardware requirements. The 55-msec timer makes use of the system-time-of-day clock; the 1-msec timer is a Turbo Pascal translation of the timer described by Bührer, Sparrer, and Weitkunat (1987). The logic of each timer is shown by a short demonstration program.