On timing events in computer-controlled experiments

This paper considers the problem of timing events in computer-controlled experiments. A digital clock is defined as a time-mark generator or “ticker” and a counter. A discussion of time-mark generators commonly used in computers is followed by a consideration of several ways in which computer clocks are implemented and used. A framework for the latter discussion is provided by a classification of clocks in terms of whether the ticker or the counter (either or both) is internal or external to the computer.