// MCU BASIC: https://www.basic4mcu.com
// DateTime : 2018-12-18 오후 11:31:08
// by Ok-Hyun Park
//
#include <mega128.h>
#include <delay.h>
#include <stdio.h>
#include <alcd.h>
//
#define  BYTE unsigned char
//
unsigned char key;
int  key_IN[4];                        //입력되는 키값 저장배열
int  sec_num[4]={0x33,0x31,0x32,0x31}; //비밀번호
int  arr_cnt=1,right=1;                //비밀번호 검사를 위한 변수 선언
int  g=0,s=0;                          //비밀번호 검사를 위한 변수선언
char i=0;                              //LCD출력을 위한 변수
//flash BYTE seg_hexfont[2]={0xc0,0xbf};
BYTE FND_selector[3]={0xBF,0xDF,0xEF};
BYTE seg_data[3]={0xbf,0xbf,0xbf};
//---------------------------------------
//
unsigned char KeyCheck(void){
  PORTE=0x10; delay_ms(1);
  //
  if     (PINE.4)return 0x30; // 0
  else if(PINE.5)return 0x34; // 4
  else if(PINE.6)return 0x38; // 8
  else if(PINE.7)return 0x41; // A
  //
  PORTE=0x20; delay_ms(1);
  //
  if     (PINE.4)return 0x31; // 1
  else if(PINE.5)return 0x35; // 5
  else if(PINE.6)return 0x39; // 9
  else if(PINE.7)return 0x42; // B
  //
  PORTE=0x40; delay_ms(1);
  //
  if     (PINE.4)return 0x32; // 2
  else if(PINE.5)return 0x36; // 6
  else if(PINE.6)return 0x2a; // *
  else if(PINE.7)return 0x43; // C
  //
  PORTE=0x80; delay_ms(1);
  //
  if     (PINE.4)return 0x33; // 3
  else if(PINE.5)return 0x37; // 7
  else if(PINE.6)return 0x23; // #
  else if(PINE.7)return 0x44; // D
  //
  return 0xff;
}
//
void sec_test(){
  if(arr_cnt==8){
    for(g=0; g<8; g++){
      if(key_IN[g]==sec_num[g])right++;
    }
    if(right==8){
      lcd_clear(); lcd_gotoxy(0,0); lcd_puts("open"); delay_ms(500);
      lcd_clear(); lcd_gotoxy(0,0); lcd_puts("password");
      PORTC=seg_data[1]; PORTD=FND_selector[2];
      arr_cnt=1; right=1; g=0; s=0; i=0;
    }
    else{
      lcd_clear(); lcd_gotoxy(0,0); lcd_puts("RETRY"); delay_ms(500);
      lcd_clear(); lcd_gotoxy(0,0); lcd_puts("password"); // LCD의 첫번째 라인
      PORTC=seg_data[2]; PORTD=FND_selector[2];
      arr_cnt=1; right=1; g=0; s=0; i=0;
    }
  }
}
//
interrupt[EXT_INT4]void RETRY(void){ lcd_clear(); lcd_puts("password"); }
interrupt[EXT_INT5]void sw5(void){ lcd_gotoxy(0,0); lcd_puts("1"); }
interrupt[EXT_INT6]void sw6(void){ lcd_gotoxy(0,1); lcd_puts("2"); }
interrupt[EXT_INT7]void sw7(void){ lcd_gotoxy(0,2); lcd_puts("3"); }
//
void main(void){
  PORTA=0xFF; DDRA=0xFF; // PORTA 출력
  PORTC=0xFF; DDRC=0xFF; // PORTC 출력
  PORTD=0xFF; DDRD=0xFF; // PORTD 출력
  lcd_clear();
  lcd_gotoxy(0,0); lcd_putsf("password");  delay_ms(100);
  DDRE=0xff;
  //
  EICRB=0xff; EIFR|=0xf0; EIMSK=0x0f; // 상승 에지
  SREG=0x80;
  while(1){
    key=KeyCheck();
    if(key!=0xff){
      lcd_gotoxy(i,1);  delay_ms(1000);
      lcd_putchar(key); delay_ms( 500);
      if(i<15)i++;
      sec_test();
    }
  }
}
 
PE4~PE7은 키 스캔 입력, 키스캔 출력, 외부인터럽트 등 몇군데에서 사용하고 있습니다.
출력에 스위치를 연결하면 고장납니다.
회로도 참고해서 수정하세요
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