freq_meas.c

一种多功能频率计

#include<reg52.h>
#include<Freq_Meas.h>
#include <lcd1602.h>

uchar str4[]="Over range!";
uint freq;

void Freq_Meas(uint count,uchar flag)	
{	
	EX0=1;
  ET1=1;
	TR1=1;
	count=0;
	EA=1;
	if(count>50000)
	{
		gotoxy(2,7);
		display_LCD_string(str4);
	}
	else if(count<=50000&&count>1000&&flag==1)
	{
		P3^0;	 //选择200分频
		P3^1;
		freq=count*200;
	}
	else if(count<=1000&&flag==2)
	{
		P3^0;		//选择100分频
		P3^1;
		count=0;
		flag=0;
		while(1)
		{
			if(count>=10)
				{
					P3^0;		 //选择直通
					P3^1;
					if(count<10&&flag==10)
						{
						
							freq=count/10;
						}
					else 
						freq=count;
					break;
				}
			}
	}
		else if(flag==2)
			freq=count*100;
			
  flag=0;
	gotoxy(2,7);
	display_LCD_number(freq);
}