超声波模块Echo电平一直是低

Pcbbar · 发表于 2022-7-13 17:31:49

问问各位该怎么解决，不知道怎么修改

你好我是河源人 · 发表于 2022-7-13 17:32:49

这是我的代码

#include <STC15F2K60S2.H>
#include <intrins.h>

#define uchar unsigned char
#define uint unsigned int
#define ulong unsigned long

sbit led_sel=P2^3;

uchar code duanxuan[]={ 0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};

sbit Trig=P1^0;
sbit Echo=P1^1;

uchar data_H,data_L;
uint distance;
void Init(){
P0M0=0XFF;
P0M1=0X00;

P2M0=0XFF;
P2M1=0X00;

TR1=1;
TR0=0;

TMOD=0x11;
AUXR=0xC0;

EA=1;
ET0=0;
ET1=1;

TH1=(65536-60000)/256;
TL1=(65535-60000)%256;
}

void S_Init(){
Trig=0;
Echo=0;
}

void Delay20us()//@11.0592MHz
{
unsigned char i;

_nop_();
_nop_();
_nop_();
i = 52;
while (--i);
}

void Timer1() interrupt 3{
EA=0;
TH1=(65536-60000)/256;
TL1=(65536-60000)%256;

Trig=1;
Delay20us();
Trig=0;

while(Echo==0);
TH0=0;
TL0=0;

TR0=1;
while(Echo==1);
data_H=TH0;
data_L=TL0;

TH0=0;
TL0=0;

distance=data_H;
distance=distance<<8;
distance=distance|data_L;
distance=distance/58;

EA=1;
}

void Delay10us()//@11.0592MHz
{
unsigned char i;

_nop_();
i = 25;
while (--i);
}

void seg_display(){
uchar ge_data,shi_data,bai_data;
bai_data=distance/100;
shi_data=distance%100/10;
ge_data=distance%100/10%10;

led_sel=0;

P0=0x00;
P2=0x00;
Delay10us();
P2=0x00;
P0=duanxuan[bai_data];
Delay10us();
P2=0x01;
P0=duanxuan[shi_data];
Delay10us();
P2=0x01;
P0=duanxuan[ge_data];
Delay10us();
}

void main(){
Init();
S_Init();
while(1){
seg_display();
}
}

xiaozhubanna · 发表于 2022-7-13 17:33:48

把你的S_Init()函数删去再试试

xiang18 · 发表于 2022-7-13 17:34:34

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

#define uint unsigned int
#define uchar unsigned char
#define LCD1602 P0

sbit E=P2^7;
sbit RS=P2^6; //写数据or命令
sbit RW=P2^5;//读or写数据

sbit TRIG=P3^7;//产生脉冲
sbit ECHO=P3^6;//接收脉冲

uchar zm[]={0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38};//在LCD1602上的0~9
uint h,l,flag=0,sum;//高八位低八位接收成功标志高电平时长
uchar dist_[4]; //存储距离的各个位

void Delay1ms(uint a)
{
uint i;
while(a--)
{
for(i=0;i<1000;i++)
_nop_();
}
}

void Delay1us(uint a)
{
while(a--)
{
_nop_();
}
}

void LcdWriteCom(uchar com)
{
E=0;
RS=0;
RW=0;

LCD1602=com;
Delay1ms(1);
E=1;
Delay1ms(5);
E=0;
}

void LcdWriteDat(uchar dat)
{
E=0;
RS=1;
RW=0;

LCD1602=dat;
Delay1ms(1);
E=1;
Delay1ms(5);
E=0;
}

void LcdInit()
{
LcdWriteCom(0x38);  //开显示
LcdWriteCom(0x0c);  //开显示不显示光标
LcdWriteCom(0x06);  //写一个指针加1
LcdWriteCom(0x01);  //清屏
LcdWriteCom(0x80);  //设置数据指针起点
}

void InitTime()
{
TMOD=0X01;//定时器0 工作方式1
TH0=(65536-1)/256;//1us
TL0=(65536-1)%256;
ET0=1;
}

void Dat_chuli()
{
uint dist;
dist=sum*170/10000;  //cm
dist_[3]='\0';
dist_[2]=dist/100;
dist_[1]=dist%100/10;
dist_[0]=dist%10;
}

void Lcd_xianshi()
{
uchar i;
LcdWriteCom(0x80);
for(i=0;dist_!='\0';i++)
{
LcdWriteDat(zm[dist_]);
}
}
void main()
{
uint i=0;
LcdInit();  // lcd1602初始化
InitTime();  //定时器0初始化
IT0=1;  //下降沿触发
EA=1;
while(1)
{
TRIG=0;
ECHO=0;
Delay1ms(10);
TRIG=1;
Delay1us(20);//输出一个20us的高脉冲
TRIG=0;


while(ECHO==0); //等待回波
flag=0;
EX0=1; //打开中断0 计时器0
TH0=0;
TL0=0;
TR0=1;
//*********************************高电平结束，进入中断0函数
while(TH0<30);//等待测量结果
TR0=0;
TH0=0;
TL0=0;

if(flag==1)
{
sum=h*256+l;//计算接收总时长
}
else
{
sum=0;
}
Dat_chuli(); //计算距离并将其各个位分开
Lcd_xianshi(); //将得到的结果显示到Lcd1602上
}
}

void Time0() interrupt 1
{
TH0=0;
TL0=0;
flag=0; //回波过长，测量失败
}

void It0() interrupt 0
{
h=TH0; //提取ECHO负跳变瞬间计时器的时间
l=TL0;
flag=1; //接收成功
EX0=0;//关闭中断0
}