串口通信232.c

单片机的485和232串口通讯

#include<stdio.h>
#include<reg51.h>

#define P1~7=1


#define uchar unsigned char

uchar shuju[32]={0};
 uchar j=0,k=0,l=0,flag=0;

void send( uchar dat )	 
{											 
     SBUF=dat;
	 while(TI==0);
	 TI=0;
}
void sendstr(uchar *p,uchar n)
{
	 uchar i=0;
	 EA=0;
	 for(i=0;i<n;i++)
	 {  
	    SBUF=*(p+i);
	    while(TI==0);
		TI=0;
	 }
	 EA=1;

}
void receive(void) interrupt 4
{
    if(RI!=0)
  { 
  	uchar i;
	i=SBUF;
    if(i==0xff)
	    { 
		    l=j;
		  	j=0;
			//flag=1;
			sendstr(shuju,l);
		 }
	 else
		{
	        //flag=0;
			shuju[j++]=SBUF;
		} 
	 RI=0;
   }
}
void main()
{
      uchar j=10;
      uchar xuehao[]={2,1,0,4,0,4,3,4};
      uchar fre[]={5,0,30,74};
      uchar fuzhi[]={1,5,70};
	  uchar a[]={0XFF,0x04,0x05,0x23,0x02,0x06,0x04};
	  TMOD=0x20;
	  TH1=0xfd;
	  TL1=0xfd;
	  SCON=0x50;
	  TR1=1;
	  ES=1;
	  EA=1;
	  PS=1;

  while(1)	
   {send(0x18);while(j--);}	  
  
 
}