一种基于MSP430单片机的交流频率检测系统

A System Based on MSP430 used for Measuring Frequency of AC Signal

本文提出了一种交流信号过零检测的电路,即捕获交流信号的零点,并借助MSP430单片机内部的16位定时器A(Timer A)的脉冲捕获功能便能得到该交流信号的周期进而能得到它的频率。系统的硬件部分主要由MSP430单片机以及整流桥、光电耦合器、三级管等器件构成;而软件部分主要是基于MSP430单片机的C语言程序,包括系统的初始化、定时器的设置等。该系统的实验结果和电路仿真吻合较好,具有一定的应用价值。

This paper introduces a kind of circuit of zero detecting for AC signal, In other words, the zero of AC signal can be captured. The period of an AC signal can be got by the pulse capturing function of 16 bits timer A in MSP430. In succession, its frequency can be calculated. The hardware of this system is composed of MSP430, commutating bridge, photo coupler, transistor, and some others. And the software of this system includes initialization of the system and the timer A, mainly, The program in this system is written in C language based MSP430. The experiment result is in accord with the circuit simulation, so this system can be widely applied.