基于89C51单片机技术，介绍了一种数字式频率计数器，该频率计具有操作简单方便、响应速度快、体积小等一系列优点。可以及时准确地测量低频信号的频率。-Based on the 89C51 single-chip technology, introduces a digital frequency counter, the frequency meter is simple convenient, fast response, a series of advantages of small size

这是基于单片机自动量程的频率计的PPT，里面包含了方案的总体硬件框图，以及5V稳压电源电路的设计，以及以高频为10kHz、低频为800Hz的正弦波频率和方波频率两种频率信号进行比较-This is a microcontroller based automatic frequency range meter PPT, which contains a hardware block diagram of the overall program, as well as 5V power supply

测频计，准确测量1hz-40mhz,误差范围在十万分之一左右，误差率低。-Frequency measuring meter, accurate measurement of 1 hz- 40 MHZ, error range in one over one hundred thousand, low error rate.