STC单片机4x6矩阵按键程序

以下是一个基于STC单片机的4x6矩阵按键程序的示例：

#include <reg52.h>

#define uint unsigned int
#define uchar unsigned char

sbit ROW1 = P1^0;
sbit ROW2 = P1^1;
sbit ROW3 = P1^2;
sbit ROW4 = P1^3;

sbit COL1 = P1^4;
sbit COL2 = P1^5;
sbit COL3 = P1^6;
sbit COL4 = P1^7;
sbit COL5 = P3^0;
sbit COL6 = P3^1;

uchar key_code[4][6]={
    0x31,0x32,0x33,0x34,0x35,0x36,
    0x41,0x42,0x43,0x44,0x45,0x46,
    0x51,0x52,0x53,0x54,0x55,0x56,
    0x61,0x62,0x63,0x64,0x65,0x66
};

uchar key_scan(void)
{
    uchar i,j;
    uchar code = 0xff;

    ROW1 = 0;
    if(COL1 == 0) {code = 0; i = 0; j = 0;}
    if(COL2 == 0) {code = 1; i = 0; j = 1;}
    if(COL3 == 0) {code = 2; i = 0; j = 2;}
    if(COL4 == 0) {code = 3; i = 0; j = 3;}
    if(COL5 == 0) {code = 4; i = 0; j = 4;}
    if(COL6 == 0) {code = 5; i = 0; j = 5;}
    ROW1 = 1;

    ROW2 = 0;
    if(COL1 == 0) {code = 6; i = 1; j = 0;}
    if(COL2 == 0) {code = 7; i = 1; j = 1;}
    if(COL3 == 0) {code = 8; i = 1; j = 2;}
    if(COL4 == 0) {code = 9; i = 1; j = 3;}
    if(COL5 == 0) {code = 10; i = 1; j = 4;}
    if(COL6 == 0) {code = 11; i = 1; j = 5;}
    ROW2 = 1;

    ROW3 = 0;
    if(COL1 == 0) {code = 12; i = 2; j = 0;}
    if(COL2 == 0) {code = 13; i = 2; j = 1;}
    if(COL3 == 0) {code = 14; i = 2; j = 2;}
    if(COL4 == 0) {code = 15; i = 2; j = 3;}
    if(COL5 == 0) {code = 16; i = 2; j = 4;}
    if(COL6 == 0) {code = 17; i = 2; j = 5;}
    ROW3 = 1;

    ROW4 = 0;
    if(COL1 == 0) {code = 18; i = 3; j = 0;}
    if(COL2 == 0) {code = 19; i = 3; j = 1;}
    if(COL3 == 0) {code = 20; i = 3; j = 2;}
    if(COL4 == 0) {code = 21; i = 3; j = 3;}
    if(COL5 == 0) {code = 22; i = 3; j = 4;}
    if(COL6 == 0) {code = 23; i = 3; j = 5;}
    ROW4 = 1;

    if(code != 0xff) {
        while(COL1 == 0 || COL2 == 0 || COL3 == 0 || COL4 == 0 || COL5 == 0 || COL6 == 0);
        return key_code[i][j];
    }
    else {
        return 0xff;
    }
}

void main()
{
    uchar key;

    while(1)
    {
        key = key_scan();
        if(key != 0xff) {
            // 处理按下按键的操作
        }
    }
}

这个程序的基本思路是：通过轮询检测矩阵按键的状态，然后根据按键的行列位置来确定按下的键值。在程序中，我们定义了一个 4x6 的键值表 `key_code`，用于存储每个按键对应的键值。在 `key_scan` 函数中，通过轮询检测每一行的状态，然后根据列的状态来确定按下的键值。最后在主函数中，根据返回的键值来执行相应的操作。