stc89c52超声波测距代码

以下是STC89C52RC单片机智能小车超声波测距的代码，其中Trig连接P1.5，Echo连接P1.6，使用定时器1进行计时：

#include <reg52.h>
#include <intrins.h>

#define uint unsigned int
#define uchar unsigned char

sbit Trig = P1^5;
sbit Echo = P1^6;

void delay_us(uint us)
{
    while(us--)
    {
        _nop_();
        _nop_();
        _nop_();
        _nop_();
    }
}

void delay_ms(uint ms)
{
    while(ms--)
    {
        delay_us(1000);
    }
}

void Init_Timer1(void)
{
    TMOD |= 0x10;
    TH1 = 0;
    TL1 = 0;
    TR1 = 1;
}

uint Get_Distance(void)
{
    uint distance;
    Trig = 0;
    delay_us(2);
    Trig = 1;
    delay_us(10);
    Trig = 0;
    while(!Echo);
    TH1 = 0;
    TL1 = 0;
    while(Echo);
    TR1 = 0;
    distance = TH1 * 256 + TL1;
    distance = distance / 58;
    return distance;
}

void main()
{
    uint distance;
    Init_Timer1();
    while(1)
    {
        distance = Get_Distance();
        if(distance < 30)
        {
            P2 = 0x01;
        }
        else
        {
            P2 = 0x00;
        }
        delay_ms(100);
    }
}