作者：Acebit

信息：STC10F08單片機(jī)，晶振11.0592MHZ；超聲波模塊HM55B，測距范圍1米；

LCD1602，串行發(fā)送數(shù)據(jù)，顯示單位mm；

#include "def.h" //定義管腳
#include "reg51.h"
#include
#ifndef OSC110592
#define OSC110592
#endif
unsigned int qian,bai,shi,ge;
unsigned int k;
long result;

void init();
void PULSOUTus(unsigned int port);
bit Read_Port(unsigned int port);
void Write_Port(unsigned int port,bit state);

bdata unsigned char SBUF1;
sbit SBUF1_bit0 = SBUF1^0;
sbit SBUF1_bit1 = SBUF1^1;
sbit SBUF1_bit2 = SBUF1^2;
sbit SBUF1_bit3 = SBUF1^3;
sbit SBUF1_bit4 = SBUF1^4;
sbit SBUF1_bit5 = SBUF1^5;
sbit SBUF1_bit6 = SBUF1^6;
sbit SBUF1_bit7 = SBUF1^7;

void init() //initialization
{
TMOD=0x12;
PCON=00;
TR1=0;
TF1=0;
TR0=0;
TF0=0;
ET1=0;
ET0=0;
EA=0;
}

void delay_ms(unsigned int i)//延時子程序
{
unsigned int j;
for(;i>0;i--)
for(j=0;j<125;j++);
}

void putchar(char input) //模擬串口9600波特率，向LCD發(fā)送數(shù)據(jù)
{
SBUF1=input;
TL0=160;
TH0=160;
TF0=0;
TR0=1;

P26 = 0; //strat
while(!TF0);
TF0=0;
P26 = SBUF1_bit0; //0
while(!TF0);
TF0=0;
P26 = SBUF1_bit1; //1
while(!TF0);
TF0=0;
P26 = SBUF1_bit2; //2
while(!TF0);
TF0=0;
P26 = SBUF1_bit3; //3
while(!TF0);
TF0=0;
P26 = SBUF1_bit4; //4
while(!TF0);
TF0=0;
P26 = SBUF1_bit5; //5
while(!TF0);
TF0=0;
P26 = SBUF1_bit6; //6
while(!TF0);
TF0=0;
P26 = SBUF1_bit7; //7
while(!TF0);
TF0=0;
P26 = 1; //end
while(!TF0);
TF0=0;
TR0=0;
}

void PULSOUTus(unsigned int port)//HM55B啟動脈沖
{

Write_Port(port,1);
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
Write_Port(port,0);
}

void Write_Port(unsigned int port,bit state)
{
switch (port)
{
case 0: P00=state;break;
case 1: P01=state;break;
case 2: P02=state;break;
case 3: P03=state;break;
case 4: P04=state;break;
case 5: P05=state;break;
case 6: P06=state;break;
case 7: P07=state;break;
case 8: P20=state;break;
case 9: P21=state;break;
case 10:P22=state;break;
case 11:P23=state;break;
case 12:P24=state;break;
case 13:P25=state;break;
case 14:P26=state;break;
case 15:P27=state;break;
}
}

//main program
void main()
{
init();
while(1)
{
TL1=0;
TH1=0;

Write_Port(15,0);
PULSOUTus(15);
Write_Port(15,1);
while(P27==0); //測回波時間
TR1=1;
while(P27==1);
TR1=0;

result=TH1*256+TL1;
result=result*0.187-150; //距離計(jì)算
k=(int)result;
putchar(22);//顯示
putchar(12);
delay_ms(100);
qian=k/1000+48;
bai=(k00)/100+48;
shi=(k00)0/10+48;
ge=(k00)0+48;

putchar(qian);
putchar(bai);
putchar(shi);
putchar(ge);
putchar(m);
putchar(m);
delay_ms(500);
}
}