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

#define HOURS 3
#define MINUTES 17
#define SECONDS 50
#define PERIOD 121
#define ON_TIME 2
 
void switch_line(double *a, double *b){
	double aux;
	aux = *a;
	*a = *b;
	*b = aux;
}
 
int angleToMs(double angle){
	return (int)(PERIOD * angle/360);
}
 
int main(){
	double h = HOURS, m = MINUTES, s = SECONDS; 
	double ms = 0;
	double angle_hour, angle_minute, angle_second;
	int current_time, aux;
 
	DDRD = 0xFF;
	PORTD = 63; 
 
	while(1){
		angle_hour = (double)360/12 * h + (double)360/(12*60) * m + (double)360/(12*60*60) * s;
		angle_minute = (double)360/60 * m + (double)360/(60*60) * s;
		angle_second = (double)360/60 * s;
 
		if(angle_minute > angle_second)
			switch_line(&angle_minute, &angle_second);
		if(angle_hour > angle_minute)
			switch_line(&angle_hour, &angle_minute);
		if(angle_minute > angle_second)
			switch_line(&angle_minute, &angle_second);
		current_time = 0;
		aux = angleToMs(angle_hour);
		_delay_ms(aux);
		PORTD = PORTD ^ 63; _delay_ms(ON_TIME); PORTD = PORTD ^ 63;
		current_time += (aux + ON_TIME);
 
		aux = angleToMs(angle_minute) - current_time;
		if(aux > 0){
			_delay_ms(aux);
			PORTD = PORTD ^ 63; 
			_delay_ms(ON_TIME); 
			PORTD = PORTD ^ 63;
			current_time += (aux + ON_TIME);
		}
		aux = angleToMs(angle_second) - current_time;
		if(aux > 0){
			_delay_ms(aux);
			PORTD = PORTD ^ 63; 
			_delay_ms(ON_TIME); 
			PORTD = PORTD ^ 63;
			current_time += (aux + ON_TIME);
		}
		aux = PERIOD - current_time;	
		if(aux > 0)
			_delay_ms(aux);
 
		ms += PERIOD;
		if(ms >= 1000){
			s ++;
			ms = ms - 1000;
		}
		if(s == 60)	{
			m ++;
			s = 0;
		}
		if(m == 60){
			h ++;
			m = 0;
		}
		if(h == 12)
			h = 0;
	}
	return 0;
}