This description of the use of "probeware," i.e., hardware which connects to a microcomputer and works with the software to measure factors such as temperature, light, or motion in science laboratory experiments, uses as an example an experiment which would involve the measurement of pendulum motion using the "Precision Timer…

Described is the construction of a simple analog-to-digital convertor circuit to interface an Apple II+ microcomputer to a light sensor used in conjunction with a holographic gear inspector. A list of parts, circuit diagram, and a simple BASIC program for the convertor are provided. (CW)