单片机键盘程序(4×4矩阵式)

7． C语言源程序

#include AT89X51.H>

unsigned char code table[]={0x3f,0x06,0x5b,0x4f,

0x66,0x6d,0x7d,0x07,

0x7f,0x6f,0x77,0x7c,

0x39,0x5e,0x79,0x71};

unsigned char temp;

unsigned char key;

unsigned char i,j;

void main(void)

{

while(1)

{

P3=0xff;

P3_4=0;

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

for(i=50;i>0;i--)

for(j=200;j>0;j--);

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

switch(temp)

{

case 0x0e:

key=7;

break;

case 0x0d:

key=8;

break;

case 0x0b:

key=9;

break;

case 0x07:

key=10;

break;

}

temp=P3;

P1_0=~P1_0;

P0=table[key];

temp=temp 0x0f;

while(temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

}

}

}

P3=0xff;

P3_5=0;

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

for(i=50;i>0;i--)

for(j=200;j>0;j--);

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

switch(temp)

{

case 0x0e:

key=4;

break;

case 0x0d:

key=5;

break;

case 0x0b:

key=6;

break;

case 0x07:

key=11;

break;

}

temp=P3;

P1_0=~P1_0;

P0=table[key];

temp=temp 0x0f;

while(temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

}

}

}

P3=0xff;

P3_6=0;

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

for(i=50;i>0;i--)

for(j=200;j>0;j--);

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

switch(temp)

{

case 0x0e:

key=1;

break;

case 0x0d:

key=2;

break;

case 0x0b:

key=3;

break;

case 0x07:

key=12;

break;

}

temp=P3;

P1_0=~P1_0;

P0=table[key];

temp=temp 0x0f;

while(temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

}

}

}

P3=0xff;

P3_7=0;

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

for(i=50;i>0;i--)

for(j=200;j>0;j--);

temp=P3;

temp=temp 0x0f;

if (temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

switch(temp)

{

case 0x0e:

key=0;

break;

case 0x0d:

key=13;

break;

case 0x0b:

key=14;

break;

case 0x07:

key=15;

break;

}

temp=P3;

P1_0=~P1_0;

P0=table[key];

temp=temp 0x0f;

while(temp!=0x0f)

{

temp=P3;

temp=temp 0x0f;

}

}

}

}

}