矩阵键盘检测
时间:10-02
整理:3721RD
点击:
- #include<reg52.h>
- sbit key=P3^4;
- sbit dula=P2^6;
- sbit wela=P2^7;
- #define uint unsigned int
- #define uchar unsigned char
- uchar num=0,temp;
- uchar code table[]={
- 0x3f,0x06,0x5b,0x4f,
- 0x66,0x6d,0x7d,0x07,
- 0x7f,0x6f,0x77,0x7c,
- 0x39,0x5e,0x79,0x71};
- int main()
- {
- void delay(uint z);
- dula=1;
- P0=0;
- dula=0;
- wela=1;
- P0=0xc0;
- wela=0; //段选位选锁存器
- while(1)
- {
- P3=0xfe; //P3口的八根接口与4X4矩阵键盘链接。
- temp=P3;
- temp=temp&0xf0;
- while(temp!=0xf0) //判断有无按键按下
- {
- delay(5);
- temp=P3;
- temp=temp&0xf0;
- while(temp!=0xf0)
- {
- temp=P3; //这一行是我所不能理解的。具体理由看文末
- switch(temp)
- {
- case 0xee:num=1;
- break;
- case 0xde:num=2;
- break;
- case 0xbe:num=3;
- break;
- case 0x7e:num=4;
- break;
- }
-
- dula=1;
- P0=table[num];
- dula=0;
- }
-
- }
-
- }
- return 0;
- }
- void delay(uint z)
- {
- uint t1,y;
- for(t1=z;t1>0;t1--)
- for(y=110;y>0;y--);
- }