keil软件中实现3*4矩阵键盘读取键值的代码程序和数码管实现程序

以下是基于Keil软件的3x4矩阵键盘读取键值和数码管实现程序的示例代码：

1. 3x4矩阵键盘读取键值程序：

#include <reg52.h> 

#define uchar unsigned char 
#define uint unsigned int 

sbit S0 = P1^0; //定义矩阵键盘的4个引脚
sbit S1 = P1^1; 
sbit S2 = P1^2; 
sbit S3 = P1^3; 

sbit D1 = P2^0; //定义数码管的8个引脚
sbit D2 = P2^1;
sbit D3 = P2^2;
sbit D4 = P2^3;
sbit D5 = P2^4;
sbit D6 = P2^5;
sbit D7 = P2^6;
sbit D8 = P2^7;

uchar code KeyValue[3][4] = {{'1','2','3','A'},
                            {'4','5','6','B'},
                            {'7','8','9','C'}}; //定义键值矩阵

uchar KeyValueScan() //扫描键盘函数
{
    uchar i,j,k;
    for(i=0;i<4;i++)
    {
        switch(i)
        {
            case 0: S0 = 0;S1 = 1;S2 = 1;S3 = 1;break;
            case 1: S0 = 1;S1 = 0;S2 = 1;S3 = 1;break;
            case 2: S0 = 1;S1 = 1;S2 = 0;S3 = 1;break;
            case 3: S0 = 1;S1 = 1;S2 = 1;S3 = 0;break;
        }
        k = 0;
        for(j=0;j<4;j++)
        {
            if(P1 & (0x01<<j)) k++;
        }
        if(k==1)
        {
            if(!(P1 & 0x01))
            {
                return KeyValue[0][i];
            }
            else if(!(P1 & 0x02))
            {
                return KeyValue[1][i];
            }
            else if(!(P1 & 0x04))
            {
                return KeyValue[2][i];
            }
            else if(!(P1 & 0x08))
            {
                return 'D'; //第四行第四列是D键
            }
        }
    }
    return 0;
}

void main()
{
    uchar key;
    while(1)
    {
        key = KeyValueScan(); //扫描键盘
        if(key) P0 = key; //在P0口输出键值
    }
}

2. 数码管实现程序：

#include <reg52.h> 

#define uchar unsigned char 
#define uint unsigned int 

uchar led[10] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f}; //定义数码管显示0~9的编码

sbit D1 = P2^0; //定义数码管的8个引脚
sbit D2 = P2^1;
sbit D3 = P2^2;
sbit D4 = P2^3;
sbit D5 = P2^4;
sbit D6 = P2^5;
sbit D7 = P2^6;
sbit D8 = P2^7;

void Delay(uint i) //延时函数
{
    while(i--);
}

void main()
{
    uchar i = 0;
    while(1)
    {
        D1 = 0;D2 = 1;D3 = 1;D4 = 1; //第一个数码管显示
        P0 = led[i%10];
        Delay(50000);
        D1 = 1;D2 = 0;D3 = 1;D4 = 1; //第二个数码管显示
        P0 = led[i/10];
        Delay(50000);
        D1 = 1;D2 = 1;D3 = 0;D4 = 1; //第三个数码管显示
        P0 = led[i/100];
        Delay(50000);
        D1 = 1;D2 = 1;D3 = 1;D4 = 0; //第四个数码管显示
        P0 = led[i/1000];
        Delay(50000);
        i++;
    }
}

这两个程序可以结合使用，实现读取键盘输入的数字，并在数码管上显示出来。