main.c

4X4按键程序

#include <avr/io.h>
#include <avr/signal.h>
#include <avr/interrupt.h>
#include <avr/delay.h>
const unsigned char seg_table[16]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e};
 void main (void)
{unsigned char i; 
  DDRA=0Xff;
  PORTA=0x00;
  DDRC=0Xf0;
  PORTC=0xe0; 
  do{
  DDRB = 0x0f;/*获取列地址*/
  PORTB = 0xf0;  
  _delay_ms(10);
  i = PINB;
  DDRB = 0xf0;/*获取行地址*/
  PORTB = 0x0f;
  _delay_ms(10); 
  i |= PINB; 
  DDRD=0Xff;
  PORTD=i;
  DDRA=0Xff;
  if (i==0xee)  PORTA=seg_table[0];
  if (i==0xde)  PORTA=seg_table[1];
  if (i==0xbe)  PORTA=seg_table[2];
  if (i==0x7e)  PORTA=seg_table[3];
  if (i==0xed)  PORTA=seg_table[4];
  if (i==0xdd)  PORTA=seg_table[5];
  if (i==0xbd)  PORTA=seg_table[6];
  if (i==0x7d)  PORTA=seg_table[7];
  if (i==0xeb)  PORTA=seg_table[8];
  if (i==0xdb)  PORTA=seg_table[9];
  if (i==0xbb)  PORTA=seg_table[10];
  if (i==0x7b)  PORTA=seg_table[11];
  if (i==0xe7)  PORTA=seg_table[12];
  if (i==0xd7)  PORTA=seg_table[13];
  if (i==0xb7)  PORTA=seg_table[14];
  if (i==0x77)  PORTA=seg_table[15];
  if (i==0xff)  PORTA=0x00;
  } while(1);
}