main.c

在别人有错误的基础上改进的超声波测距程序

#include <reg51.h>
#include "intrins.h"
#include "Lcd1602.h"
#define uchar unsigned char
#define uint unsigned int

sbit BEEP = P1^6;  //报警提示口
sbit vout = P1^7;  //脉冲发送口
sbit P3_2 = P3^2;  //中断接收口
//sbit INT = P1^6; 
bit flag;

//unsigned char discol[4]={0xef,0xdf,0xbf,0x7f};
unsigned char code Anum_code[]={"0123456789"};
//unsigned char disbuf[4]={0,1,2,3};
float high,low;
unsigned char qian,bai,shi,ge;
//unsigned char j=600;

/*void delay_1ms(void)  //12mhz delay 1.01ms
{
   unsigned char x,y;   
   x=3;
   while(x--) 
  {
     y=40;
     while(y--);
  }
}

void delay_1us(unsigned char i) //i=1, 5us; i=2,7us; i=3,9us
{ 
    while(--i); 
}*/

void delay_50us(unsigned int t) // t=100, 5ms; t=1000, 50ms
{
 unsigned char j;  
 for(;t>0;t--)   
  for(j=19;j>0;j--);
}

/*void delay_50ms(unsigned int t) // t=10, 500ms; t=100, 5s;
{
 unsigned int j; 
 for(;t>0;t--) 
  for(j=6245;j>0;j--);
}*/
void display(void)
{
  Write_Comm(0x01); //清显示屏
  Write_Comm(0x80);
  Write_Data(Anum_code[qian]);
  //Write_Comm(0x80);
  Write_Data(Anum_code[bai]);
  //Write_Comm(0x80);
  Write_Data(Anum_code[shi]);
  //Write_Comm(0x83);
  Write_Data(Anum_code[ge]);
}

void work(void)
{ 
  //unsigned char qian,bai,shi,ge;
  float value;
  value=(high*256+low)*17/100;
  qian=value/1000;
  bai=(value-qian*1000)/100;
  shi=(value-qian*1000-bai*100)/10;
  ge=value-qian*1000-bai*100-shi*10;
  if(value<=1000)
  {
    BEEP=0;
  }
  else
  {
    BEEP=1;
  }
  /*disbuf[0] = qian;
  disbuf[1] = bai;
  disbuf[2] = shi;
  disbuf[3] = ge;*/
}
main()
{ 
  //unsigned char i;
  //unsigned int t;
  Lcd_Init();  
  TMOD = 0x11;
  TH0 =  0;
  TL0 = 0;
  TH1 = 0;
  TL1 = 0;
  P0 = 0xff;
  P1 = 0xff;
  P2 = 0xff;
  P3 = 0xff;
  //EX0 = 1;         //允许外部中断0
  ET1 = 1;         //允许定时器1中断
  EA = 1;
  TR1 = 1;
  while(1)
 {
  //display();
  if(flag)
  {
    EA = 0;
    work();
    //EA = 0;
    display();
	//delay_50ms(100);
	//for(i=5;i>0;i--) 
       //for(t=6245;t>0;t--);
    flag = 0;
    ET0 = 0;        //禁止定时器0中断
    TH0 = 0;
    TL0 = 0;
    ET1 = 1;
	TR1 = 1;
    EA = 1;
  }
 }
}

void INTT1() interrupt 3 
{ 
  unsigned char i;
  EA = 0;
  TR1 = 0;
  EX0 = 0;           //禁止外部中断
  TH0 = 0;
  TL0 = 0;
  TH1 = 0;
  TL1 = 0;
  EA = 1;
  TR0 = 1;
  for(i=0;i<4;i++)
   {
     vout = ~vout;
     _nop_();
     _nop_();
     _nop_();
     _nop_();
     _nop_();
     _nop_();
     _nop_();
     _nop_();
   }
   delay_50us(40);
   EX0 = 1;        //开启外部中断
   //ET0 = 1;          //允许定时器0中断
   /*if(j==600)
   {
   j=j+200;
   TR0 = 1;
   EX0 = 1;        //开启外部中断  
   delay_50us(j);
   INT=0; 
   }
   else
   {
   j=j-200;
   TR0 = 1;
   EX0 = 1;        //开启外部中断  
   delay_50us(j);
   INT=0; 
   }*/
   
}

void PINT0() interrupt 0 
{
  //_nop_();
  TR0 = 0;       //关闭定时器0
  EX0 = 0;
  EA = 0;
  low = TL0;
  high = TH0;
  flag = 1;
  while(P3_2==0)
  {
    //TR0 = 0;       //关闭定时器0
	//EX0 = 0;
    //EA = 0;
    //low = TL0;
    //high = TH0;
    //low = 0x50;
    //high = 0xc3;
    //TH0 = 0;
    //TL0 = 0;
	//INT=1;
    //flag = 1;	   
	//Write_Comm(0x01); //清显示屏
	//Write_Comm(0x8f);
    //Write_Data('k');
	//delay_50ms(10);
  }  
}