uart.c

52单片机开发板的实例程序

#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char 
sbit a=P1^0;
sbit b=P1^1;
sbit c=P1^2;
uchar temp=0;
const uchar table[]={
          0x3f,0x06,0x5b,0x4f,0x66,
          0x6d,0x7d,0x07,0x7f,0x6f};
void delay(uint k)
{
  uint i;
  for(;k>0;k--)
  for(i=110;i>0;i--);
}
void HC138(uchar i)
{
  a=i&0x01;
  b=i&0x02;
  c=i&0x04;
}
void display(uchar num)
{
   uchar ge,shi,bai,qian;
   qian=num/1000;
   bai=num%1000/100;
   shi=num%100/10;
   ge=num%10;
   HC138(0);
   P2=table[ge];
   delay(2);
   HC138(1);
   P2=table[shi];
   delay(2);   
    HC138(2);
   P2=table[bai];
   delay(2); 
}
void main()
{

   	TMOD=0x20;//设置定时器1为工作方式2
	TH1=0xfd;//设置串口通信的波特率为9600
	TL1=0xfd;
	TR1=1;//开启定时器1
	SM0=0;
	SM1=1;
	REN=1;
	EA=1;
	ES=1;
	while(1)
		{	
       		display(temp);

		}
}
void IsrUart() interrupt 4
{
	ES=0;
	if(RI)
	{
		RI=0;
		temp=SBUF;

	}
	ES=1;
}