// MCU BASIC: https://www.basic4mcu.com
// DateTime : 2019-12-19 오후 10:37:23
// by Ok-Hyun Park
//
#include <avr/io.h>
#define F_CPU 800000UL
#define __DELAY_BACKWARD_COMPATIBLE__
#include <util/delay.h>
#include <avr/interrupt.h>
//
unsigned char segment[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xf8,0x80,0x90};
unsigned int  i=0,_delay=1000;
int num=0;
//
int main(void){
  DDRC=0xFE;
  DDRA=0xFF; PORTA=0xFF;
  while(1){
    PORTA=segment[num];
    for(i=0; i<_delay; i++){
      if((~PINC)&1){
        if(num==5){ num=-1;
          PORTC=0x02; _delay_ms(1000);
          _delay=_delay-100;
          if(_delay<=500){ while(1); }
        }
        else{ PORTC=0x02; while(1); }
      }
      else{ PORTC=0x00; } // <--- 여기서 먹통이 될 것 같습니다.
      _delay_ms(1);
    }
    //
    if(++num>9)num=0;
  }
}
 
 
 
if((~PINC)&1){ 
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