#define  F_CPU 7372800UL

#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
uint8_t tmp = 0xff;
uint8_t flag = 0;
uint8_t left =  0b01111111;
uint8_t right = 0b11111110;
uint16_t top = 13000;
uint16_t step = 500;
ISR(TIMER1_COMPA_vect)
{
	if(PORTA == 0b11110111)
	{
		PORTA = 0xff;
		left =  0b01111111;
		right = 0b11111110;
		flag = 0;

	}
	else
	{

	if (flag == 0)
	{
		PORTA = left;
		left = left  >> 1;
		left = left + 0b10000000;
		flag = 1;
	}
 else if (flag == 1)
	{
		PORTA = right;
		right = right << 1;
		right = right + 0x01;
		flag = 0;
	}

	}
}
ISR(INT0_vect)
{
	if(OCR1A > step)
	{
		OCR1A = OCR1A - step;
	}

}
ISR(INT1_vect)
{
	if(OCR1A < top-step)
	{
		OCR1A = OCR1A + step;
	}
}


int main(void)
{
	DDRA = 0xff;
	PORTA = 0xff;

	DDRB = 0x00;
	PORTB = _BV(0) | _BV(1);

	TCCR1A = 0x00;
	TCCR1B = _BV(WGM12) | _BV(CS11) | _BV(CS10);
	OCR1A = 25519;

	TIMSK = _BV(OCIE1A);
	MCUCR = _BV(ISC01) | _BV(ISC11);
	GICR = _BV(INT0) | _BV(INT1);
	sei();

	while(1)
	{
		if(bit_is_clear(PINB, 0))
		{
			if(OCR1A > step)
			{
				OCR1A = OCR1A - step;

			}
			_delay_ms(150);
		}

		if(bit_is_clear(PINB, 1))
		{
			if(OCR1A < top-step)
			{
				OCR1A = OCR1A + step;
			}
			_delay_ms(150);
		}
	}

}