50hz方波发生器.c

单片机C语言15个实验附有原理图和程序 是我的课程作业 以经过实践验证

//题1：要求从P17输出50Hz的方波，然后显示1秒钟实测的方波数，以实证50Hz频率是否正确。
//int0+int1
#include <stdio.h>
#include <reg51.h>
#include <intrins.h>
#define hi 0x3c//5Hz 0xd8//50Hz 0xfc//500Hz   0xff//100us5000Hz  0xd8//50Hz  
#define lo 0xb0//5Hz 0xf0//50Hz 0x18//500Hz 0x9c//100us5000Hz    0xf0//50Hz   
#define uchar unsigned char
#define uint unsigned int
sbit P10=P1^0;sbit P17=P1^7;
sbit P20=P2^0;sbit P21=P2^1;sbit P22=P2^2;
unsigned char k=0,flag,sec,disp[4],mask=0xee;
unsigned int t0_count,int_count;
unsigned char code ledk[16]
       ={0x3f,0x06,0x5b,0x4f,0x66,0x6d,
        0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71 };
sbit P37=P3^7;sbit clk=P0^7;sbit sda=P0^6;               //74LS164
void delay (unsigned int n)
{unsigned int i,j;
 for(i=0;i<n;i++)
   for(j=0;j<n ;j++);   }
void shift(unsigned char dx)
{unsigned char j=0;
 while(j<8)
	{if((dx&0x80)!=0) sda=1;
       else  sda=0;
	   clk=0;clk=1;
	   dx<<=1;j++;}  }
void hextodec_int(unsigned  int xx)
{unsigned  char B;
 B=xx/1000;        disp[3]=B;
xx=xx%1000;
 B=xx/100;         disp[2]=B;
xx=xx%100;
 B=xx/10;          disp[1]=B;
xx=xx%10;
 B=xx;             disp[0]=B;}
void  int0() interrupt 0
{ int_count++;    }
void t0() interrupt 1
{TH0=hi;TL0=lo;t0_count++;    //k++;  //5HZ
 //if(k==2){P10=!P10;k=0;}           //5HZ
 if(t0_count==20){TR0=0;flag=1;t0_count=0;}  }
 //5000Hz 10000,500Hz 1000,50Hz 100  5Hz 20
void display( )
{static unsigned char i;
   shift(ledk[disp[i]]);P2=mask;
   mask=_crol_(mask,1);i++;if(i>3)i=0;    } 	    
void out()
{hextodec_int(int_count);
  display();    }  
void main(void)
{TMOD=0x01;TH0=hi;TL0=lo;
 ET0=1;EX0=1;IT0=1;EA=1;int_count=0;P10=0;flag=0;TR0=1;
 while(1)
  { 
   	if(flag==1){out();delay(10); } 
  }    }