led_num.c

51单片机实验例程

/*****************************************************************************************
*																                         *
*	                 LED点阵实验(流动显示1 2 3 4 5 6 7 8 9)								 *
*	说明 通过P0 和 P2 作为点阵接口								                         *
*要求学员掌握 LED点阵的工作原理和 各点阵脚的定义及接法，具体接线请参考接线说明		     *
*我们采用的LED点阵式是低功耗，在做实验时可以用单片机脚直接驱动	                         *
******************************************************************************************/


#include<reg51.h>

unsigned char code tab[]={0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};


unsigned char code digittab[18][8]={

{0x00,0x00,0x3e,0x41,0x41,0x41,0x3e,0x00}, //0

{0x00,0x00,0x00,0x00,0x21,0x7f,0x01,0x00}, //1

{0x00,0x00,0x27,0x45,0x45,0x45,0x39,0x00}, //2

{0x00,0x00,0x22,0x49,0x49,0x49,0x36,0x00}, //3

{0x00,0x00,0x0c,0x14,0x24,0x7f,0x04,0x00}, //4

{0x00,0x00,0x72,0x51,0x51,0x51,0x4e,0x00}, //5

{0x00,0x00,0x3e,0x49,0x49,0x49,0x26,0x00}, //6

{0x00,0x00,0x40,0x40,0x40,0x4f,0x70,0x00}, //7

{0x00,0x00,0x36,0x49,0x49,0x49,0x36,0x00}, //8

{0x00,0x00,0x32,0x49,0x49,0x49,0x3e,0x00}, //9

{0x00,0x00,0x7F,0x48,0x48,0x30,0x00,0x00}, //P

{0x00,0x00,0x7F,0x48,0x4C,0x73,0x00,0x00}, //R

{0x00,0x00,0x7F,0x49,0x49,0x49,0x00,0x00}, //E

{0x00,0x00,0x3E,0x41,0x41,0x62,0x00,0x00}, //C

{0x00,0x00,0x7F,0x08,0x08,0x7F,0x00,0x00}, //H

{0x00,0x00,0x00,0xFF,0xFF,0x00,0x00,0x00}, //I

{0x00,0x7F,0x10,0x08,0x04,0x7F,0x00,0x00}, //N

{0x7C,0x48,0x48,0xFF,0x48,0x48,0x7C,0x00}  //中

};

unsigned int timecount;

unsigned char cnta;

unsigned char cntb;

void main(void)

{

TMOD=0x01;

TH0=(65536-3000)/256;

TL0=(65536-3000)%256;

TR0=1;	   //开启定时0
ET0=1;	    

EA=1;	   //开启中断

cntb=0;
  
while(1)

{ ;

}

}


/*************************************************
*
*	   定时中断
********************************************************/		                                    
void t0(void) interrupt 1 using 0
{

  TH0=(65536-3000)/256;	 //定时器高位装载数据
  TL0=(65536-3000)%256;	 //定时器低位装载数据

  if(cntb<18) //红色
  {
    P1=0xFF;
    P2=tab[cnta];
    P0=digittab[cntb][cnta];
  }
  else //绿色
  {
    P2=0xFF;
    P1=tab[cnta];
    P0=digittab[cntb-18][cnta];
  }


  if(++cnta>=8) cnta=0;
  if(++timecount>=333)
  {
    timecount=0;
    if(++cntb>=36)cntb=0;
  }

}