串行.c

数码管的串行显示。有时候IO口不够用时候

#include<reg51.h>
#define uchar unsigned char
#define uint  unsigned int
uint z,num,numduan;
uchar temp,numwei=0,numwei1;
static west=0;

uchar code tableduan[]={       //键盘表
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};

uchar code tablewei[]={
0xfe,0xfd,0xfb,0xf7,
0xef,0xdf,0xbf,0x7f};



void init();
void sent(uchar aa);
void receive();
uchar jianpan();
void display(uchar dis);
uchar cc;

void main()
{
    init();
    while(1)
     {
       numduan=jianpan();
       display(cc);

     if(west) {
      cc=numduan;
      sent(numduan);
      west=0;  }
      
      
    receive();
      

     }

}

void init()
{
  SM0=0;
   SM1=1;
   REN=1;
   TMOD=0x20;
   TH1=0xfd;
   TL1=0xfd;
   TR1=1;
   TI=0;

 }

//------------------------------------------------
void delay(uint z)

  {
       uint x,y;
     for(x=z;x>0;x--)
       for(y=120;y>0;y--);
   }


void display(uchar dis)
{

    P0=tableduan[dis];
    P2=0;


}

//--------------------------------键盘子程序：

 uchar jianpan( )
    {
           P1=0xfe;
           temp=P1;
           temp=temp&0xf0;

           if(temp!=0xf0)

	            {
	               delay(5);
	               temp=P1;
	               temp=temp&0xf0;
	               if(temp!=0xf0)
		                {
		                  temp=P1;
		                switch(temp)
			                  {
			                     case 0xee: num=1; break;
					 case 0xde: num=2; break;
				   	 case 0xbe: num=3; break;
					 case 0x7e: num=4; break;
			                  }
		                }
	                while(temp!=0xf0)                   //松手检测
		                 {
		                     temp=P1;
		                     temp=temp&0xf0;
                                     west=1;

		                  }
	             }



//-------------------------------------------
       P1=0xfd;
           temp=P1;
           temp=temp&0xf0;

           if(temp!=0xf0)

	            {
	               delay(5);
	               temp=P1;
	               temp=temp&0xf0;
	               if(temp!=0xf0)
		                {
		                  temp=P1;
		                switch(temp)
			                  {
			                     case 0xed: num=5; break;
					     case 0xdd: num=6; break;
					     case 0xbd: num=7; break;
					     case 0x7d: num=8; break;
			                  }
		                }
	                while(temp!=0xf0)                   //松手检测
		                 {
		                     temp=P1;
		                     temp=temp&0xf0;
                                     west=1;

		                  }
	             }


//-------------------------------------------
        P1=0xfb;
        temp=P1;
        temp=temp&0xf0;

         if(temp!=0xf0)

           {
                delay(5);
               temp=P1;
               temp=temp&0xf0;
               if(temp!=0xf0)
                {
                  temp=P1;
                switch(temp)
                  {
                     case 0xeb: num=9; break;
		 case 0xdb: num=10; break;
		 case 0xbb: num=11; break;
		 case 0x7b: num=12; break;
                  }
                }
                    while(temp!=0xf0)                   //松手检测
	                 {
	                     temp=P1;
	                     temp=temp&0xf0;
                             west=1;

	                  }
             }


//-----------------------------------------------
        P1=0xf7;
        temp=P1;
        temp=temp&0xf0;

         if(temp!=0xf0)

           {
               delay(5);
               temp=P1;
               temp=temp&0xf0;
               if(temp!=0xf0)
                {
                  temp=P1;
                switch(temp)
                  {
                     case 0xe7: num=12; break;
					 case 0xd7: num=13; break;
				   	 case 0xb7: num=14; break;
					 case 0x77: num=15; break;
                  }
                }
                     while(temp!=0xf0)                   //松手检测
	                 {
	                     temp=P1;
	                     temp=temp&0xf0;
                             west=1;

	                  }
             }

   return num;
 }

void sent(uchar aa)
{
   SBUF=aa;
   while(1)
     {
     if(TI)
        {TI=0;
         break;
        }
      }
}
void receive()
{  uchar bb;
  while(RI)
  {cc=SBUF;
    RI=0;
    }
}