#define F_CPU 16000000
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>

#define seg_a ~(1<<PA0)
#define seg_b ~(1<<PA1)
#define seg_c ~(1<<PA2)
#define seg_d ~(1<<PA3)
#define seg_e ~(1<<PA4)
#define seg_f ~(1<<PA5)
#define seg_g ~(1<<PA6)
#define seg_kropka ~(1<<PA7)

#define C0 (seg_a & seg_b & seg_c & seg_d & seg_e & seg_f)
#define C1 (seg_b & seg_c)
#define C2 (seg_a & seg_b & seg_d & seg_e & seg_g)
#define C3 (seg_a & seg_b & seg_c & seg_d & seg_g)
#define C4 (seg_b & seg_c & seg_f & seg_g)
#define C5 (seg_a & seg_c & seg_d & seg_f & seg_g)
#define C6 (seg_a & seg_c & seg_d & seg_e & seg_f & seg_g)
#define C7 (seg_a & seg_b & seg_c)
#define C8 (seg_a & seg_b & seg_c & seg_d & seg_e & seg_f & seg_g)
#define C9 (seg_a & seg_b & seg_c & seg_d & seg_f & seg_g)


#define W1 ~(1<<PC0)
#define W2 ~(1<<PC1)
#define W3 ~(1<<PC2)
#define W4 ~(1<<PC3)




volatile uint8_t setne,sekundy,dziesietne,dziesiatki;
volatile uint8_t a=1,b=2,c=3,d=4;

volatile uint8_t tab1[] = {C0,C1,C2,C3,C4,C5,C6,C7,C8,C9};



int main(void) {

	// USTAWIENIA ADC *****************************************************************
	ADMUX |= (1<<REFS0)|(1<<REFS1); // 1,1V  VREF
	ADCSRA |= (1<<ADEN); // ADC ENABLE
	ADCSRA |= (1<<ADPS0)|(1<<ADPS1)|(1<<ADPS2); // preskaler

	// USTAWIENIA PORTÓW **************************************************************

	DDRC |= 0xff;
	PORTC |= 0xff;

	DDRA |= 0xff;
	PORTA |= 0xff;

	// USTAWIENIA TIMERA 0 ************************************************************

	TCCR0 |= (1<<CS00)|(1<<CS02);  // preskaler 1024
	TCNT0 = 204;
	TIMSK |= (1<<TOIE0);

	sei(); // globalne zezwolenie na przerwania

	while(1) {

	}
}
ISR (TIMER0_OVF_vect) {
	TCNT0 = 194;
	switch(a) {
	case 0:
		PORTC |= W4;
		PORTA |= 0xff;
		PORTC &= ~W1;
		PORTA = tab1[a];
		a++;
		break;

	case 1:
		PORTC |= W1;
		PORTA |= 0xff;
		PORTC &= ~W2;
		PORTA = tab1[b];
		a++;
		break;

	case 2:
		PORTC |= W2;
		PORTA |= 0xff;
		PORTC &= ~W3;
		PORTA = tab1[c];
		a++;
		break;

	case 3:
		PORTC |= W3;
		PORTA |= 0xff;
		PORTC &= ~W4;
		PORTA = tab1[d];
		a=0;
		break;
	}
}