Question

各位大虾，有基于51单片机超声波测距的教学视频么？跪求！！！！！！

Answer 1

程序给你吧 看了就明白了
#include <AT89x51.H> //器件配置文件
#include <intrins.h>
#define RX P3_4 //ECH0
#define TX P3_3 //TRIG
#define LCM_RW P3_1 //定义LCD引脚
#define LCM_RS P3_2
#define LCM_E P3_0
#define LCM_Data P0
//#define Key_Data P2_0 //定义Keyboard引脚
//#define Key_CLK P3_2
#define Busy 0x80 //用于检测LCM状态字中的Busy标识
void LCMInit(void);
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char DData);
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char code *DData);
void Delay5Ms(void);
void Delay400Ms(void);
void Decode(unsigned char ScanCode);
void WriteDataLCM(unsigned char WDLCM);
void WriteCommandLCM(unsigned char WCLCM,BuysC);
unsigned char ReadDataLCM(void);
unsigned char ReadStatusLCM(void);
unsigned char code Cls[] = {" "};
unsigned char code ASCII[15] = {'0','1','2','3','4','5','6','7','8','9','.','-','M'};
static unsigned char DisNum = 0; //显示用指针
unsigned int time=0;
unsigned long S=0;
bit flag =0;
unsigned char disbuff[4] ={ 0,0,0,0,};

//写数据
void WriteDataLCM(unsigned char WDLCM)
{
ReadStatusLCM(); //检测忙
LCM_Data = WDLCM;
LCM_RS = 1;
LCM_RW = 0;
LCM_E = 0; //若晶振速度太高可以在这后加小的延时
LCM_E = 0; //延时
LCM_E = 1;
}
//写指令
void WriteCommandLCM(unsigned char WCLCM,BuysC) //BuysC为0时忽略忙检测
{
if (BuysC) ReadStatusLCM(); //根据需要检测忙
LCM_Data = WCLCM;
LCM_RS = 0;
LCM_RW = 0;
LCM_E = 0;
LCM_E = 0;
LCM_E = 1;
}
//读数据
unsigned char ReadDataLCM(void)
{
LCM_RS = 1;
LCM_RW = 1;
LCM_E = 0;
LCM_E = 0;
LCM_E = 1;
return(LCM_Data);
}
//读状态
unsigned char ReadStatusLCM(void)
{
LCM_Data = 0xFF;
LCM_RS = 0;
LCM_RW = 1;
LCM_E = 0;
LCM_E = 0;
LCM_E = 1;
while (LCM_Data & Busy); //检测忙信号
return(LCM_Data);
}
void LCMInit(void) //LCM初始化
{
LCM_Data = 0;
WriteCommandLCM(0x38,0); //三次显示模式设置，不检测忙信号
Delay5Ms();
WriteCommandLCM(0x38,0);
Delay5Ms();
WriteCommandLCM(0x38,0);
Delay5Ms();
WriteCommandLCM(0x38,1); //显示模式设置,开始要求每次检测忙信号
WriteCommandLCM(0x08,1); //关闭显示
WriteCommandLCM(0x01,1); //显示清屏
WriteCommandLCM(0x06,1); // 显示光标移动设置
WriteCommandLCM(0x0F,1); // 显示开及光标设置
}
//按指定位置显示一个字符
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char DData)
{
Y &= 0x1;
X &= 0xF; //限制X不能大于15，Y不能大于1
if (Y) X |= 0x40; //当要显示第二行时地址码+0x40;
X |= 0x80; //算出指令码
WriteCommandLCM(X, 1); //发命令字
WriteDataLCM(DData); //发数据
}
//按指定位置显示一串字符
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char code *DData)
{
unsigned char ListLength;
ListLength = 0;
Y &= 0x1;
X &= 0xF; //限制X不能大于15，Y不能大于1
while (DData[ListLength]>0x19) //若到达字串尾则退出
{
if (X <= 0xF) //X坐标应小于0xF
{
DisplayOneChar(X, Y, DData[ListLength]); //显示单个字符
ListLength++;
X++;
}
}
}
//5ms延时
void Delay5Ms(void)
{
unsigned int TempCyc = 5552;
while(TempCyc--);
}
//400ms延时
void Delay400Ms(void)
{
unsigned char TempCycA = 5;
unsigned int TempCycB;
while(TempCycA--)
{
TempCycB=7269;
while(TempCycB--);
};
}
/********************************************************/
void Conut(void)
{
time=TH0*256+TL0;
TH0=0;
TL0=0;

S=(time*1.7)/100; //算出来是CM
if((S>=700)||flag==1) //超出测量范围显示“-”
{
flag=0;

DisplayOneChar(0, 1, ASCII[11]);
DisplayOneChar(1, 1, ASCII[10]); //显示点
DisplayOneChar(2, 1, ASCII[11]);
DisplayOneChar(3, 1, ASCII[11]);
DisplayOneChar(4, 1, ASCII[12]); //显示M
}
else
{
disbuff[0]=S%1000/100;
disbuff[1]=S%1000%100/10;
disbuff[2]=S%1000%10 %10;
DisplayOneChar(0, 1, ASCII[disbuff[0]]);
DisplayOneChar(1, 1, ASCII[10]); //显示点
DisplayOneChar(2, 1, ASCII[disbuff[1]]);
DisplayOneChar(3, 1, ASCII[disbuff[2]]);
DisplayOneChar(4, 1, ASCII[12]); //显示M
}
}
/********************************************************/
void zd0() interrupt 1 //T0中断用来计数器溢出,超过测距范围
{
flag=1; //中断溢出标志
}
/********************************************************/
void StartModule() //启动模块
{
TX=1; //启动一次模块
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
_nop_();
TX=0;
}
/********************************************************/
void delayms(unsigned int ms)
{
unsigned char i=100,j;
for(;ms;ms--)
{
while(--i)
{
j=10;
while(--j);
}
}
}
/*********************************************************/
void main(void)
{
unsigned char TempCyc;
Delay400Ms(); //启动等待，等LCM讲入工作状态
LCMInit(); //LCM初始化
ReadDataLCM();//测试用句无意义
for (TempCyc=0; TempCyc<10; TempCyc++)
Delay400Ms(); //延时
DisplayListChar(0, 1, Cls);
while(1)
{
TMOD=0x01; //设T0为方式1，GATE=1；
TH0=0;
TL0=0;
ET0=1; //允许T0中断
EA=1; //开启总中断

while(1)
{
StartModule();
// DisplayOneChar(0, 1, ASCII[0]);
while(!RX); //当RX为零时等待
TR0=1; //开启计数
while(RX); //当RX为1计数并等待
TR0=0; //关闭计数
Conut(); //计算
delayms(80); //80MS

}
}
}