超声波传感器测距并数码管显示程序

#include   <reg51.H>
#include   <math.h> 
#include   <intrins.h>
#include   <STDIO.H>
#define uchar unsigned  char
#define uint  unsigned   int  
#define ulint unsigned long int 
#define ul unsigned long 
//********定义变量*****************************
unsigned char const discode[] ={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};//共阴极数码管字形表
unsigned char const positon[3]={ 0xf8,0xf9,0xfa};//位选
unsigned char dis[3]={0,0,0};
uchar time=0;
sbit TX = P3^4;
sbit RX= P3^5;

ul i;
uint distence;
//********定义函数*****************************
void    delay(uint k);
void   display(void);
void chaosheng(void);
void delay1ms(uint m); 
void timer_Init(void);
//***************串口初始化 9600 bps @ 12 MHz ************************

void timer_Init()  /*定时器初始化函数*/
{
TMOD = 0x11;
TH0 = 0x00;