#ifndef ENABLE_BIT_DEFINITIONS
  #define ENABLE_BIT_DEFINITIONS
#endif

#ifndef F_CPU
//  #define F_CPU 3686400UL
  #define F_CPU 1000000UUL
#endif

#include <intrinsics.h>
#include <iom8.h>

enum {UP, DOWN};

unsigned int uiPwm;
unsigned char ucDirection;

#pragma vector = TIMER1_OVF_vect
__interrupt void btn(void)
{
  switch ( ucDirection )
  {
  case UP:
    if ( ++uiPwm == 1023 )
      ucDirection = DOWN;
    break;
  case DOWN:
    if ( --uiPwm == 0 )
      ucDirection = UP;
    break;
  }
  OCR1A = uiPwm;
  PORTB = ~(PORTB & 0x01 );
};


int main()
{
  // Init Pin PB1
  DDRB |= ( 0x01 << PB1 );
  DDRB |= ( 0x01 << PB0 );

  // Fast PWM, 8bit
  TCCR1A |= ( 0x02 << COM1A0 );
  TCCR1A |= ( 0x01 << WGM10 );
  TCCR1B |= ( 0x01 << WGM12 );

  // Allow T/C Interrupt
  TIMSK |= ( 0x01 << TOIE1 );

  // Initial value
  OCR1A = 0;

  // Start PWM with no prescaler
//  TCCR1B |= ( 0x01 << CS10 );

  // Start PWM with CLK/8
  TCCR1B |= ( 0x02 << CS10 );

  __enable_interrupt();

  while ( 1 )
  {
  }

  return 0;
};