C51单片机：用数码管显示0到999的值。求c语言程序和原理图

Question

如题所述

Answer 1

#include<reg51.h>

#define uchar unsigned char

uchar temp;

int key1,key,disbuf;// 此表为 LED 的字模 0 1 2 3 4 5 6 7 8 9 a b c d e f

unsigned char code LED7Code[] = {0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F,0x77,0x7C,0x39,0x5E,0x79,0x71};

unsigned char ledx[8];

bit  s0,s1;

void delay(uchar z)

  {

  uchar i,j;

  for(i=0;i<120;i++)

  for(j=0;j<z;j++);

  }

void scan()   //要是按键了，扫描键盘编码值

  {

  P1=0xF0;

  delay(1);

  temp=P1;

  switch(temp)

    {

    case 0xe0: key1=0;

    break;

    case 0xd0: key1=1;

    break;

    case 0xb0: key1=2;

    break;

    case 0x70: key1=3;

    break;

    }

  P1=0x0f;

  delay(1);

  temp=P1;

  switch(temp)

    {

    case 0x0E: key=key1+0;

    break;

    case 0x0D: key=key1+4;

    break;

    case 0x0B: key=key1+8;

    break;

    case 0x07: key=key1+12;

    break;

    default : key=-1; 

    }

  if((key1+1)&&(key+1)) disbuf=key;

  }

void ejjc()  //判断是否按键

  {

  P1=0xF0;

  if(P1!=0xF0) { scan();s0=1;}

  else { s0=0; s1=1;}

  }

void main()

  {

  uchar i;

  while(1)

    {

    ejjc();

    if(s0==1  && s1==1)

      {

      s0=0;s1=0;

      for(i=0;i<8;i++)

        { ledx[i]=ledx[i+1]; ledx[8]=disbuf; }

      }

    P0=0xff;

    P2=LED7Code[ledx[0]];

    P0=0xfe;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[1]];

    P0=0xfd;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[2]];

    P0=0xfb;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[3]];

    P0=0xf7;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[4]];

    P0=0xef;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[5]];

    P0=0xdf;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[6]];

    P0=0xbf;

    delay(5);

    P0=0xff;

    P2=LED7Code[ledx[7]];

    P0=0x7f;

    delay(5);

    }

  }