蓝桥杯单片机超声波

在使用超声波,必须将蓝桥杯板子上的J2的1和3,2和4脚用跳线帽连在一起。

我们通过P10和P11来分别发送和接收，利用声音在空气中的传播速度为340m/s,来计算出板子到阻挡物之间的距离

1.位定义

sbit TX = P1^0;
sbit RX = P1^1;

2.定时器初始化及发送接收函数

void Time0Init()
{
	AUXR &= 0x7f;
	TMOD &= 0xf0;
	TL0 = 0xF4;
	TH0 = 0xFF;
	TF0 = 0;
	TR0 = 0;
}

unsigned char Ware_Recv()
{
	unsigned  char ucDist, ucNum = 10;
	
	TX = 0;
	TL0 = 0xf4;
	TH0 = 0xff;
	TR0 = 1;
	while(ucNum--)
	{
		while(!TF0);
		TX ^= 1;
		TF0 = 0;
	}
	TR0 = 0;
	TL0 = 0;
	TH0 = 0;
	TR0 = 1;
	while(RX && !TF0);
	TR0 = 0;
	if(TF0)
	{
		TF0 = 0;
		ucDist = 255;
	}
	else
	{
		ucDist = ((TH0<<8)+TL0)*0.017;
	}
	return ucDist;
}

#include 
#include "intrins.h"

sfr AUXR = 0x8e;

sbit TX = P1^0;
sbit RX = P1^1;

typedef unsigned char u8;
typedef unsigned int u16;

u8 yi,er,san,si,wu,liu,qi,ba;
u16 dds;

unsigned char code smg_duanma[]={
	0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,
	0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,
	0xbf,0x7f
};

void SelectHC573(u8 channel)
{
	switch(channel)
	{
		case 0:
			P2=P2&0x1f|0x00;
		break;
		case 4:
			P2=P2&0x1f|0x80;
		break;
		case 5:
			P2=P2&0x1f|0xa0;
		break;
		case 6:
			P2=P2&0x1f|0xc0;
		break;
		case 7:
			P2=P2&0x1f|0xe0;
		break;
	}
}

void Display_bit(u8 pos,u8 vlaue)
{
	SelectHC573(6);P0=0x01< 
这个代码雏形出自于官方，和一般的使用12ms延时具有一定的不闪屏的优点。