// MCU BASIC: https://www.basic4mcu.com
// DateTime : 2018-06-03 오후 11:34:50
// by Ok-Hyun Park
//
#include <avr/io.h>
#define F_CPU 16000000UL
#include <util/delay.h>
#include <avr/interrupt.h>
#include <stdlib.h>
//
unsigned char A[]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7C,0x07,0x7F,0x67};
volatile int a=0,b=0,c=0,d=0;
//
void Buzzer(){
  if((b==c)&&(c==d)){ TCCR0=0b01111110; OCR0=190; TCCR0=0; OCR0=0; }
  else              { DDRG=0x00; PORTG=0x00; PORTA=0xff; _delay_ms(1000); PORTA=0; a++; }
}
//
void Fnd_Random(){
  if(a==0){ b=rand()%8; }
  if(a==1){ PORTG=0x08; PORTC=A[b]; _delay_ms(5); c=rand()%8; }
  if(a==2){
    PORTG=0x08; PORTC=A[b]; _delay_ms(5);
    PORTG=0x04; PORTC=A[c]; _delay_ms(5);
    d=rand()%8;
  }
  if(a==3){
    PORTG=0x08; PORTC=A[b]; _delay_ms(5);
    PORTG=0x04; PORTC=A[c]; _delay_ms(5);
    PORTG=0x02; PORTC=A[d]; _delay_ms(5);
    Buzzer();
  }
  if(a==4){ PORTG=0x00; }
}
//
ISR(INT4_vect){
  _delay_ms(1);
  if(++a>=5)a=0;
}
//
int main(void){
  DDRA=0xff; DDRB=0x10; DDRC=0xff; DDRG=0x0f; DDRE=0xef;
  EICRB=0x02; EIMSK=0x10; // 하강엣지
  sei();
  while(1){
    Fnd_Random();
  }
}