AVR128的程序——矩陣按鍵

#include

#define uchar unsigned char

#define uint unsigned int

void Delayms(uint MS);

uchar key_scan(void);

void init_io(void);

uchar led_discode[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,

0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,0xff};

uchar key_val=0;

void main (viod)

{

uchar key_io;

init_io();

while(1)

{

PORTD=0XF0;

Delayms(5);

key_io=PIND & 0xf0;

if(key_io !=0xf0)

{

PORTD=0XF0;

Delayms(1);

key_io=PIND & 0xf0;

if(key_io !=0xf0)

{

key_val=key_scan();

key_val |= key_io ;

}

switch(key_val)

{

case 0xee: key_val=0x00; break; //按鍵K1

case 0xde: key_val=0x01; break; //按鍵K2

case 0xbe: key_val=0x02; break; //按鍵K3

case 0x7e: key_val=0x03; break; //按鍵K4

case 0xed: key_val=0x04; break; //按鍵K5

case 0xdd: key_val=0x05; break; //按鍵K6

case 0xbd: key_val=0x06; break; //按鍵K7

case 0x7d: key_val=0x07; break; //按鍵K8

case 0xeb: key_val=0x08; break; //按鍵K9

case 0xdb: key_val=0x09; break; //按鍵K10

case 0xbb: key_val=0x0a; break; //按鍵K11

case 0x7b: key_val=0x0b; break; //按鍵K12

case 0xe7: key_val=0x0c; break; //按鍵K13

case 0xd7: key_val=0x0d; break; //按鍵K14

case 0xb7: key_val=0x0e; break; //按鍵K15

case 0x77: key_val=0x0f; break; //按鍵K16

}

}

PORTD=0XF0;

key_io=PIND & 0xf0;

while(key_io !=0xf0)

{

key_io=PIND & 0xf0;

}

PORTC=led_discode[key_val];

}

}

void init_io(void)

{

DDRA=0XFF;

PORTA=0XFF;

DDRB=0XFF;

PORTB=0XFF;

DDRC=0XFF;

PORTC=0XFF;

DDRD=0X0F;

PORTD=0XF0;

DDRF=0X0E;

PORTF=0X0E;

PORTF&=0XF7;

DDRB |=0X10;

PORTB|=0X10;

}

uchar key_scan(void)

{

uchar m,temp=0xf7;

for(m=0;m<4;m++)

{

PORTD=temp | 0xf0;

Delayms(1);

if((PIND & 0XF0)!=0XF0)

return(temp & 0x0f);

temp>>=1;

}

}

void Delayms(uint MS)

{

uint i,j;

for( i=0;i

for(j=0;j<1141;j++);

}