An experimental time-shared computer system has been used to control and collect data from a Hall effect experiment. In addition to selection of the voltage sequence and control of specimen current and magnetic flux directions, the computer exerts positive control over the specimen temperature in accordance with a series of thermocouple voltages entered by the operator at the beginning of the run. The interface circuitry is constructed from four general purpose modules and a single special purpose unit. Details of the interface system and the programs used to control the experiment and to perform intermediate calculations are given. It was found that the time-shared system was well-suited to control an experiment of this type. The demands on the computer were essentially similar to those required by a human user interacting in a conversational mode. Substantial savings in time over manual data collection and reduction were realized; a temperature run with 38 to 40 data points between 10 and 320 K could be completed in less than 4 hours.

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