51单片机——共阴数码管实验

数码管中有8位数字，从右往左分别为LED1、LED2、...、LED8，如下图所示

如何实现点亮单个数字，用下图中的ABC来实现

P2.2管脚控制A，P2.3管脚控制B，P2.4管脚控制C

//定义数码管位选管脚
sbit LSA=P2^2;
sbit LSB=P2^3;
sbit LSC=P2^4;

   for(i=0;i<8;i++){
       //位选
       switch(i){
           case 0:
               LSC=1,LSB=1,LSA=1; //7：LED8
               break;
           case 1:
               LSC=1,LSB=1,LSA=0; //6：LED7
               break;
           case 2:
               LSC=1,LSB=0,LSA=1; //5：LED6
               break;
           case 3:
               LSC=1,LSB=0,LSA=0; //4：LED5
               break;
           case 4:
               LSC=0,LSB=1,LSA=1; //3：LED4
               break;
           case 5:
               LSC=0,LSB=1,LSA=0; //2：LED3
               break;
           case 6:
               LSC=0,LSB=0,LSA=1; //1：LED2
               break;
           case 7:
               LSC=0,LSB=0,LSA=0; //0：LED1
               break;
       }
   }

每一位有8段，如下图所示

eg显示0：0 0 1 1 1 1 1 1

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DP(小数点) G F E D C B A

//段码数据
u8 gsmg_code[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};

//0 1 2 3 4 5 6 7 8 9 A B C D E F

P0端控制数码管

1、静态数码管实验

#include "reg51.h"
typedef unsigned int u16;
typedef unsigned char u8;
//数码管显示数字的数组（共阴数码管）
u8 gsmg_code[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71}; //0-F
#define SMG_A_DP_PORT P0
//控制静态数码管显示数字0，即让P0端口输出数字0的段码0x3f（共阴）
void main(){
   while(1){
       //显示数字0
       SMG_A_DP_PORT=gsmg_code[0];
   }
}

2、动态数码管实验

#include "reg51.h"
typedef unsigned int u16;
typedef unsigned char u8;
//段码数据
u8 gsmg_code[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
#define SMG_A_DP_PORT P0
//定义数码管位选管脚
sbit LSA=P2^2;
sbit LSB=P2^3;
sbit LSC=P2^4;
void delay(u16 time){
   while(time--);
}
//动态数码管
void smg_display(){
   u16 i=0;
   for(i=0;i<8;i++){
       //位选
       switch(i){
           case 0:
               LSC=1,LSB=1,LSA=1; //7
               break;
           case 1:
               LSC=1,LSB=1,LSA=0; //6
               break;
           case 2:
               LSC=1,LSB=0,LSA=1; //5
               break;
           case 3:
               LSC=1,LSB=0,LSA=0; //4
               break;
           case 4:
               LSC=0,LSB=1,LSA=1; //3
               break;
           case 5:
               LSC=0,LSB=1,LSA=0; //2
               break;
           case 6:
               LSC=0,LSB=0,LSA=1; //1
               break;
           case 7:
               LSC=0,LSB=0,LSA=0; //0
               break;
       }
       SMG_A_DP_PORT=gsmg_code[i];
       delay(5000);
       SMG_A_DP_PORT=0x00; //消隐
   }
}
void main(){
   while(1){
       smg_display();
   }
}