RTIME: a program for time-series measurements and evaluation in electrophysiology with the AT-PC

This work describes a program which uses a standard RS232-serial interface of an IBM-AT-compatible microcomputer to receive via four data lines input from any laboratory equipment (spike discriminators, stimulus equipment, etc.) generating pulses between 0 to -15 V (low) and +5 to +15 V (high). Therefore, program operation is independent from any hardware extensions of the computer. The time of occurrence of input pulses is recorded with a resolution of 10 microseconds. Depending on processor speed and optional on-line display of interval histograms, a maximum sampling rate of 1.3-6 kHz is attained. Designed primarily for electrophysiological applications, the program comprises an extensive set of functions for off-line analysis of data either in the time- or in the phase-domain. The program is controlled by menu-selectable commands with detailed on-line explanation and is therefore suited for use even by operators without computer experience, e.g., students on courses in experimental physiology. Elaborate schemes of evaluation can be defined as macro commands to speed up and simplify complex data analysis in actual research.