目录
1矩阵键盘的识别
2相关c语言
3实践编程
1矩阵键盘的识别
假设按列扫描按下S6P30：0P34：1然后高流向低，P34：0，刚开始是0xf0：1111 0000
后面是0xe0：1110 0000 ，当是0xe0能确定是第一列被按下，再按行扫描，S6：0x0e
综合：0xee
2相关c语言
略
3实践编程
#include<reg52.h>
#include<intrins.h>#define uint unsigned int
#define uchar unsigned charsbit DU = P2^6;
sbit WE = P2^7;uchar num;//数码管的值
uchar KeyValue = 20;//按键值,初始值是-
//code固定table的值,code很大8k,ram区小
//共阴数码管段选值
uchar code table[] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,
0x77,0x7c,0x39,0x5e,0x79,0x71,0x76,0x38,0x37,0x3e,0x40,0x00};
void delay(unsigned int xms) //@12.000MHz
{unsigned char i, j;while(xms--){i = 2;j = 239;do{while (--j);} while (--i);}
}void KeyScan()
{//4*4//列扫描P3=0xf0;if(P3!=0xf0){//消抖delay(10);if(P3!=0){switch(P3)//判断哪一列{case 0xe0: KeyValue = 0; break;case 0xd0: KeyValue = 1; break;case 0xb0: KeyValue = 2; break;case 0x70: KeyValue = 3; break;}//行扫描P3=0x0f;switch(P3)//判断哪一行{case 0x0e: KeyValue = KeyValue; break;case 0x0d: KeyValue = KeyValue + 4; break;case 0x0b: KeyValue = KeyValue + 8; break;case 0x07: KeyValue = KeyValue + 12; break;}//松手（当我们松手后，电流无法流到地，通过上拉电阻回到初始状态while(P3 != 0x0f);}//独立按键P3=0xff;if(P3!=0xff){delay(10);if(P3!=0xff){switch(P3)//判断哪一行{case 0xfe: KeyValue = 16; break;case 0xfd: KeyValue = 17; break;case 0xfb: KeyValue = 18; break;case 0xf7: KeyValue = 19; break;}//松手（当我们松手后，电流无法流到地，通过上拉电阻回到初始状态while(P3 != 0xff);}}}}}
void main()
{WE = 1;P0=0xfb;//位选给0WE = 0;//锁存器锁存while(1){KeyScan();DU = 1;P0 = table[KeyValue];//0000 0110 共阴极给1亮DU = 0;}
}
)
