Based on pulse counting principle, the high precision time interval can be obtained by measuring the number of the high-frequency reference clock through it.

设计了一种高精度时间间隔测量模块，该模块由单片机控制，采用脉冲计数原理，通过测量时间间隔内高频参考时钟个数，得到被测时间间隔的精确值。

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This paper analyses principle, error, and unstable state of determining the electric stop watch by means of time-interval method of electric counter. A simple gate-control method is presented at last.

分析了电子计数器时间间隔法测定电秒表的原理、误差及不稳定性，并且介绍了一种简便的门控法。

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