#include <avr/io.h>
#define F_CPU 16000000UL
void Tdelay();
int main(void){
  DDRB |= (1<<PB3);
  PORTB |= (1<<PB3);
  while (1)
  { PORTB = PORTB ^ (1<<PB3);
    Tdelay();
  }
}
	DDRL |= (1 << PL4); // Make PL4 (OC5B / Arduino D45) an output
	TCCR5A |= (1 << COM5B1) | (1 << WGM51);
	TCCR5B |= (1 << WGM53) | (1 << WGM52) | (1 << CS50);
	ICR5 = 39999;
	OCR5B = 200;  // set arbitrary