/* 난수발생 코드
 * GccApplication15.c
 *
 * Created: 2019-05-16 오후 12:36:05
 * Author : admin
 */ 
     
#include <avr/io.h>
#include <avr/interrupt.h>
#define F_CPU 16000000UL
#include <util/delay.h>
unsigned char digit[10] = {0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7c, 0x07, 0x7f, 0x67};
unsigned char fnd_sel[4] = {0x01, 0x02, 0x04, 0x08};
volatile int sw1 = 0;
     
ISR(INT4_vect)
{
 sw1++;
 _delay_ms(10);
}
     
void display_fnd(int sw1)
{
 int i, fnd[4];
 if(sw1 == 0)
 {fnd[3] = 0;
 fnd[2] = 0;
 fnd[1] = 0;
 fnd[0] = 0;}
 else if (sw1 == 1)
 {fnd[3] = 0;
 fnd[2] = 0;
 fnd[1] = 0;
 fnd[0] = rand()%10;}
 else if (sw1 == 2)
 {fnd[3] = 0;
 fnd[2] = 0;
 fnd[1] = rand()%10;
 fnd[0] = fnd[0];}
 else if (sw1 == 3)
 {fnd[3] = 0;
 fnd[2] = rand()%10;
 fnd[1] = fnd[1];
 fnd[0] = fnd[0];}
 else if (sw1 == 4)
 {fnd[3] = rand()%10;
 fnd[2] = fnd[2];
 fnd[1] = fnd[1];
 fnd[0] = fnd[0];}
 
 for (i=0; i<4; i++)
 {
  PORTC = digit[fnd[i]];
  PORTG = fnd_sel[i];
  _delay_ms(2);
 }
}
     
int main(void)
{
    DDRC = 0xff;
 DDRG = 0x0f;
 DDRE = 0xef;
 EICRB = 0x02;
 EIMSK = 0x10;
 sei();
 while (1) 
    {
  display_fnd(sw1);
 
 }
}
     
 
 
노래 함수
 
#define F_CPU 16000000UL // 16 MHz
 
#include <avr/io.h>
 
#include <avr/interrupt.h>
 
#include <util/delay.h>
 
//
 
#define DO  0
 
#define RE  1
 
#define MI  2
 
#define FA  3
 
#define SOL 4
 
#define RA  5
 
#define SI  6
 
#define DDO 7
 
#define HI  8
 
#define HI2 9
 
 
 
#define EOS  -1    // End Of Song  표시
 
#define ON   0
 
#define OFF  1
volatile char f_table[10]={17,43,66,77,97,114,117,137,253,254}; //각 음계
 
 
int song1[]={DDO,HI,DDO,HI,DDO,HI,DDO,HI,DDO,HI,EOS}; //당첨 노래
 
 
 
 
volatile int tone, state;
 
ISR(TIMER0_OVF_vect)
{
	if(state == ON)
	{
		PORTB = 0x00;
		state = OFF;
	}
	else
	{
		PORTB = 0x10;
		state = ON;
	}
	TCNT0 = f_table[tone];
}
 
 
 
//
 
int main()
{
	int i=0;
	DDRB = 0x10;
	TCCR0 = 0x03; //32분주
	TIMSK = 0x01; // 오버플로
	TCNT0 = f_table[song1[i]];
	sei();
	do
	{
		tone = song1[i++];
		_delay_ms(100);
	} while (tone != EOS);
 
	
}
 
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