矩阵键盘控制12864显示最经典程序

#include //这个程序的功能：用4*4的矩阵键盘（接P3口）按键盘k1——k16中的任何一个键ki

#include //12864液晶上显示数字i-1 （液晶数据口接P0）

#define uint unsigned int//键盘扫描的思想是将行设置为低，列设置为高，来读取P3口的值，就能知道是哪个按键按下了

#define uchar unsigned char

#define LCDdata P0

sbit E = P2^7;

sbit RW = P2^6;

sbit RS = P2^5;

void init();

void delayms(uint x);

void displaykey();

void write_com(uchar com);//写命令

void write_data(uchar date);//写数据

uchar temp;

//--------------主函数-----------------

void main()

{

init();// P3=0xfe;//P3=0xfd;//P3=0xfb;//P3=0xf7;

while(1)

{

displaykey();

}

}

//-------------液晶初始化----------------

void init()

{

write_com(0x01);

write_com(0x02);

write_com(0x06);

write_com(0x0e);

}

//------------毫秒延时---------------

void delayms(uint x)

{

uchar i;

while(x--)

{

for(i=0;i<120;i++);

}

}

//------------写命令-----------------

void write_com(uchar com)

{

RS = 0;

RW = 0;

E = 0;

LCDdata = com;

E = 1;

delayms(5);

E = 0;

}

//-------------写数据------------------

void write_data(uchar date)

{

RS = 1;

RW = 0;

E = 0;

LCDdata = date;

E = 1;

delayms(5);

E = 0;

}

//----

void displaykey()

{ //****************************判断第一行的键盘

P3=0xfe; temp=P3; temp=temp&0xf0;

while(temp!=0xf0)//判断是否有键盘按下为真有键盘按下

{ delayms(50); temp=P3; temp=temp&0xf0;

while(temp!=0xf0)//再次判断是否有键盘按下为真有键盘按下

{ temp=P3;

switch(temp)

{

case 0xee:write_com(0x80);write_data('0');write_com(0x81);write_data(' ');break;

case 0xde:write_com(0x80);write_data('1');write_com(0x81);write_data(' ');break;

case 0xbe:write_com(0x80);write_data('2');write_com(0x81);write_data(' ');break;

case 0x7e:write_com(0x80);write_data('3');write_com(0x81);write_data(' ');break;

}break;//这个break很重要不能丢下，若丢下会这这个中退步出来

}

}

//******************************判断第二行的键盘

P3=0xfd; temp=P3; temp=temp&0xf0;

while(temp!=0xf0)

{ delayms(50); temp=P3; temp=temp&0xf0;

while(temp!=0xf0)

{ temp=P3;

switch(temp)

{

case 0xed:write_com(0x80);write_data('4');write_com(0x81);write_data(' ');break;

case 0xdd:write_com(0x80);write_data('5');write_com(0x81);write_data(' ');break;

case 0xbd:write_com(0x80);write_data('6');write_com(0x81);write_data(' ');break;

case 0x7d:write_com(0x80);write_data('7');write_com(0x81);write_data(' ');break;

} break;

}

}

//******************************判断第三行的键盘

P3=0xfb; temp=P3; temp=temp&0xf0;

while(temp!=0xf0)

{ delayms(50); temp=P3; temp=temp&0xf0;

while(temp!=0xf0)

{ temp=P3;

switch(temp)

{

case 0xeb:write_com(0x80);write_data('8');write_com(0x81);write_data(' ');break;

case 0xdb:write_com(0x80);write_data('9');write_com(0x81);write_data(' ');break;

case

0xbb:write_com(0x80);write_data('1');write_com(0x81);write_data('0');break;

case

0x7b:write_com(0x80);write_data('1');write_com(0x81);write_data('1');break;

}break;

}

}

//******************************判断第四行的键盘

P3=0xf7; temp=P3; temp=temp&0xf0;

while(temp!=0xf0)