数码管的显示（共阴）

51单片机上有八个共阴数码管，这时候想要亮某个位置的数码管就需要位码了，位码在低电平时有效，那么位码的数组如下：0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f，分别代表了八个位置。共阴数码管的段码和共阳的不一样，0~f如下：0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71。

下面是八个数码管显示0~7的程序

#include 
#include "./delay/delay.h"

#define SEGPORT P3

sbit bit_select = P2^0;      //位码
sbit seg_select = P2^1;       //段码

unsigned char segdata[16] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
unsigned char bitdata[8] = {0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};

void main()
{
    unsigned char i;
    SEGPORT = 0;
    while(1)
    {
        for(i = 0; i < 8; i++)
  	{
	    SEGPORT = 0x0;
	    seg_select = 1;
	    seg_select = 0;
					
	    SEGPORT = 0xff;
	    bit_select = 1;
	    bit_select = 0;   //消除重影
					
	    SEGPORT = segdata[i];
	    seg_select = 1;
	    seg_select = 0;   
					  
	    SEGPORT = bitdata[i];
	    bit_select = 1;
	    bit_select = 0;
					
	    delay_ms(2);
	}					
    }
}