#include<avr/io.h>
#include<util/delay.h>
#include"LCD.h"

#define SIG 0x01

unsigned char password[4] = "1234"; //패스워드
unsigned char pass_buf[4] = "0000"; //현재의 패스워드를 저장 할 버퍼
unsigned char msg1[ ] = "Password : ";
unsigned char msg2[ ] = "Correct pass!!";
unsigned char msg3[ ] = "Incorrect pass!!";
unsigned char cnt=0,loop=1;

void Port_init(void)
{
  DDRB = 0xff; PORTB=0x00;
 DDRE = 0xff; PORTE=0x00;
 DDRF = 0x1f; PORTF=0xff;
}

unsigned char scan_key(void)
{
  unsigned char Scan_signal=0, scan_value=0;
  unsigned int i;
  for(i=0;i<4;i++)
  {
  Scan_signal = ~(SIG << i);
  PORTF = Scan_signal;
  if((PINF & 0xe0) != 0xe0)
  {
   scan_value= (PINF & 0xe0)|(Scan_signal & 0x0f);
  }
  while((PINF & 0xe0) != 0xe0); //키가 눌려 있을 경우
  }

  return scan_value;
}

void save_buf(unsigned char number)
{
 pass_buf[cnt++] = number;
 LCD_data(number);
}

void display_key(unsigned char input)
{
 switch(input)
 {
  case 0xce : save_buf(0x30+1); break;// 1
  case 0xae : save_buf(0x30+2); break;// 2
  case 0x6e : save_buf(0x30+3); break;// 3
  case 0xcd : save_buf(0x30+4); break;// 4
  case 0xad : save_buf(0x30+5); break;// 5
  case 0x6d : save_buf(0x30+6); break;// 6
  case 0xcb : save_buf(0x30+7); break;// 7
  case 0xab : save_buf(0x30+8); break;// 8
  case 0x6b : save_buf(0x30+9); break;// 9
  case 0xc7 : save_buf(0x23);   break;// #
  case 0xa7 : save_buf(0x30);   break;// 0
  case 0x67 : save_buf(0x2A);   break;// *
 }
}

void compare_pw(void)
{
 if(cnt==4)
 {
  unsigned int i, pw_error=0;
  for(i=0;i<4;i++) // 패스워드 비교
  {
   if(password[i]!=pass_buf[i])pw_error++;
  }
 
  if(pw_error==0) //패스워드가 맞을 때 
  {
   LCD_cmd(0x00); _delay_ms(2); //display clear;
   LCD_cmd(0x01); _delay_ms(2); //cursor return home;
   LCD_str_out(msg2); _delay_ms(100);
   cnt=0;
   loop=0;
   LCD_cmd(0x00); _delay_ms(2);
   LCD_cmd(0x01); _delay_ms(2);
  }
  else   //패스워드가 틀릴 때
  {  
   LCD_cmd(0x00); _delay_ms(2); //display clear;
   LCD_cmd(0x01); _delay_ms(2); //cursor return home;
   LCD_str_out(msg3); _delay_ms(100);
   cnt=0;
   loop=1;
   LCD_cmd(0x00); _delay_ms(2);
   LCD_cmd(0x01); _delay_ms(2);
   LCD_str_out(msg1);
  }
 }
}

void main()
{
 Port_init();
 LCD_init();
 while(1)
 {
  LCD_str_out(msg1);
  while(loop)
  {
   display_key(scan_key());
   compare_pw();
  }
  loop=1;
 }
}

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