51单片机直接驱动共阴极数码管

数码管种类：

  少量的数码管实际可以直接用单片机驱动（如4个数码管）。数码管数码管有两种：共阴极和共阳极数码管。虽然只是一个极性的不同，实际应用时大有不同（根据网上资料小结如下）：

现在手里只有共阴的数码管（LG5011AH），按照网上搜索到的下图实现：

实际用的单片机是AT89S51，参考上面的的图做了适当的修改，用P2控制段，P3控制位。

所有与单片机的连接均用排针。

   参考下图即可方便的在51和2051之间轻松转换：

   完成的板子如下。与上次比有几处改进：采用USB供电，供电电路加500mA过流保护自恢复保险（USB口旁黄色像瓷片电容），单片机的P0~P3全部用排针引出。当然加了LED数码管、排阻。

LED驱动的段显控制：

首先确定显示的段，将段按顺序转换成二进制数字，进而转换成十进制数字。

假设P2.0~P2.6按顺序接到a-h段

 [page]

程序（C语言）

//这是采用查询方式的，比较占CUP资源,

# include
typedef unsigned char uchar;
//这里定义了所有二进制--十六进制转换
#define B00000000 0x0
#define B00000001 0x1
#define B00000010 0x2
#define B00000011 0x3
#define B00000100 0x4
#define B00000101 0x5
#define B00000110 0x6
#define B00000111 0x7
#define B00001000 0x8
#define B00001001 0x9
#define B00001010 0xa
#define B00001011 0xB
#define B00001100 0xc
#define B00001101 0xd
#define B00001110 0xe
#define B00001111 0xf

#define B00010000 0x10
#define B00010001 0x11
#define B00010010 0x12
#define B00010011 0x13
#define B00010100 0x14
#define B00010101 0x15
#define B00010110 0x16
#define B00010111 0x17
#define B00011000 0x18
#define B00011001 0x19
#define B00011010 0x1a
#define B00011011 0x1B
#define B00011100 0x1c
#define B00011101 0x1d
#define B00011110 0x1e
#define B00011111 0x1f

#define B00100000 0x20
#define B00100001 0x21
#define B00100010 0x22
#define B00100011 0x23
#define B00100100 0x24
#define B00100101 0x25
#define B00100110 0x26
#define B00100111 0x27
#define B00101000 0x28
#define B00101001 0x29
#define B00101010 0x2a
#define B00101011 0x2B
#define B00101100 0x2c
#define B00101101 0x2d
#define B00101110 0x2e
#define B00101111 0x2f

#define B00110000 0x30
#define B00110001 0x31
#define B00110010 0x32
#define B00110011 0x33
#define B00110100 0x34
#define B00110101 0x35
#define B00110110 0x36
#define B00110111 0x37
#define B00111000 0x38
#define B00111001 0x39
#define B00111010 0x3a
#define B00111011 0x3B
#define B00111100 0x3c
#define B00111101 0x3d
#define B00111110 0x3e
#define B00111111 0x3f

#define B01000000 0x40
#define B01000001 0x41
#define B01000010 0x42
#define B01000011 0x43
#define B01000100 0x44
#define B01000101 0x45
#define B01000110 0x46
#define B01000111 0x47
#define B01001000 0x48
#define B01001001 0x49
#define B01001010 0x4a
#define B01001011 0x4B
#define B01001100 0x4c
#define B01001101 0x4d
#define B01001110 0x4e
#define B01001111 0x4f

#define B01010000 0x50
#define B01010001 0x51
#define B01010010 0x52
#define B01010011 0x53
#define B01010100 0x54
#define B01010101 0x55
#define B01010110 0x56
#define B01010111 0x57
#define B01011000 0x58
#define B01011001 0x59
#define B01011010 0x5a
#define B01011011 0x5B
#define B01011100 0x5c
#define B01011101 0x5d
#define B01011110 0x5e
#define B01011111 0x5f

#define B01100000 0x60
#define B01100001 0x61
#define B01100010 0x62
#define B01100011 0x63
#define B01100100 0x64
#define B01100101 0x65
#define B01100110 0x66
#define B01100111 0x67
#define B01101000 0x68
#define B01101001 0x69
#define B01101010 0x6a
#define B01101011 0x6B
#define B01101100 0x6c
#define B01101101 0x6d
#define B01101110 0x6e
#define B01101111 0x6f

#define B01110000 0x70
#define B01110001 0x71
#define B01110010 0x72
#define B01110011 0x73
#define B01110100 0x74
#define B01110101 0x75
#define B01110110 0x76
#define B01110111 0x77
#define B01111000 0x78
#define B01111001 0x79
#define B01111010 0x7a
#define B01111011 0x7B
#define B01111100 0x7c
#define B01111101 0x7d
#define B01111110 0x7e
#define B01111111 0x7f

#define B10000000 0x80
#define B10000001 0x81
#define B10000010 0x82
#define B10000011 0x83
#define B10000100 0x84
#define B10000101 0x85
#define B10000110 0x86
#define B10000111 0x87
#define B10001000 0x88
#define B10001001 0x89
#define B10001010 0x8a
#define B10001011 0x8B
#define B10001100 0x8c
#define B10001101 0x8d
#define B10001110 0x8e
#define B10001111 0x8f

#define B10010000 0x90
#define B10010001 0x91
#define B10010010 0x92
#define B10010011 0x93
#define B10010100 0x94
#define B10010101 0x95
#define B10010110 0x96
#define B10010111 0x97
#define B10011000 0x98
#define B10011001 0x99
#define B10011010 0x9a
#define B10011011 0x9B
#define B10011100 0x9c
#define B10011101 0x9d
#define B10011110 0x9e
#define B10011111 0x9f

#define B10100000 0xa0
#define B10100001 0xa1
#define B10100010 0xa2
#define B10100011 0xa3
#define B10100100 0xa4
#define B10100101 0xa5
#define B10100110 0xa6
#define B10100111 0xa7
#define B10101000 0xa8
#define B10101001 0xa9
#define B10101010 0xaa
#define B10101011 0xaB
#define B10101100 0xac
#define B10101101 0xad
#define B10101110 0xae
#define B10101111 0xaf

#define B10110000 0xB0
#define B10110001 0xB1
#define B10110010 0xB2
#define B10110011 0xB3
#define B10110100 0xB4
#define B10110101 0xB5
#define B10110110 0xB6
#define B10110111 0xB7
#define B10111000 0xB8
#define B10111001 0xB9
#define B10111010 0xBa
#define B10111011 0xBb
#define B10111100 0xBc
#define B10111101 0xBd
#define B10111110 0xBe
#define B10111111 0xBf

#define B11000000 0xc0
#define B11000001 0xc1
#define B11000010 0xc2
#define B11000011 0xc3
#define B11000100 0xc4
#define B11000101 0xc5
#define B11000110 0xc6
#define B11000111 0xc7
#define B11001000 0xc8
#define B11001001 0xc9
#define B11001010 0xca
#define B11001011 0xcB
#define B11001100 0xcc
#define B11001101 0xcd
#define B11001110 0xce
#define B11001111 0xcf

#define B11010000 0xd0
#define B11010001 0xd1
#define B11010010 0xd2
#define B11010011 0xd3
#define B11010100 0xd4
#define B11010101 0xd5
#define B11010110 0xd6
#define B11010111 0xd7
#define B11011000 0xd8
#define B11011001 0xd9
#define B11011010 0xda
#define B11011011 0xdB
#define B11011100 0xdc
#define B11011101 0xdd
#define B11011110 0xde
#define B11011111 0xdf

#define B11100000 0xe0
#define B11100001 0xe1
#define B11100010 0xe2
#define B11100011 0xe3
#define B11100100 0xe4
#define B11100101 0xe5
#define B11100110 0xe6
#define B11100111 0xe7
#define B11101000 0xe8
#define B11101001 0xe9
#define B11101010 0xea
#define B11101011 0xeB
#define B11101100 0xec
#define B11101101 0xed
#define B11101110 0xee
#define B11101111 0xef

#define B11110000 0xf0
#define B11110001 0xf1
#define B11110010 0xf2
#define B11110011 0xf3
#define B11110100 0xf4
#define B11110101 0xf5
#define B11110110 0xf6
#define B11110111 0xf7
#define B11111000 0xf8
#define B11111001 0xf9
#define B11111010 0xfa
#define B11111011 0xfB
#define B11111100 0xfc
#define B11111101 0xfd
#define B11111110 0xfe
#define B11111111 0xff

uchar code helloB[] ={B01110110,B01111001,B00111000,B00111111};    //HELLO

const unsigned char LED7Code[]={
 0x3F,  // 0
 0x06,  // 1
 0x5B,  // 2
 0x4F,  // 3
 0x66,  // 4
 0x6D,  // 5
 0x7D,  // 6
 0x07,  // 7
 0x7F,  // 8
 0x6F,  // 9
 0x77,  // A
 0x7C,  // B
 0x39,  // C
 0x5E,  // D
 0x79,  // E
 0x71  // F
 
};
 [page]
void delay(int n);
void display0_F();
void displayHELLO();
//
void main(void)
{
   
    P2=0xff;   //先将段码关闭
    P3=0xff;   //将位码关闭
    delay(20);//等待一会
 
    while(1)
  {
   displayHELLO();
   display0_F();
  }
}

void delay(int n)    // 0.01*n 秒
{
    int j;
    uchar k;
    for(j=0;j   {
    for(k=255;k>0;k--);
  }
}
void display0_F()    //显示全8和0~F
{
uchar i,j,m;
for (m=100;m>0;m--)  
  {
   for(i=0;i<=3;i++)
   {
     P2=0x00;
     P3=~(0x01<      P2=0xff; //输出段码到P2口
     
     delay(5);
   }
  
    }
 
 for(j=0;j<16;j++){
    for (m=30;m>0;m--)   //显示30次约0.3秒
  {
   for(i=0;i<=3;i++)
   {
     P2=0x00;
     P3=~(0x01<      if((i+j)<16)
       P2=LED7Code[i+j];    //输出段码到P2口
     else
       P2=0;
     
     delay(5);
   }
  
    }

 
    P2=0xff;     //关闭段码
    P3=0xff;     //关闭位码
    delay(5);   //等待0.3秒
    } 

}
void displayHELLO()    //显示HELO
{
   uchar i,m;
   for (m=200;m>0;m--)  
  {
   for(i=0;i<=3;i++)
   {
     P2=0x00;
     P3=~(0x01<      P2=helloB[i]; //输出段码到P2口      
     delay(5);
   }
  
    }
}