Dieser Sketch bringt die LED des Arduino zum blinken.

arduino_led_blinken

/*
 * GccApplication2.cpp
 *
 * Created: 13.07.2015 14:24:32
 *  Author: Michael
 */ 
#ifndef F_CPU
#define F_CPU 16000000UL
#endif
#include <util/delay.h>
#include <avr/io.h>
int main(void)
{
	DDRB = (1 << DDB5);
    while(1)
    {
        PORTB = (1 << DDB5);
		_delay_ms(100);
		PORTB = (0 << DDB5);
		_delay_ms(100);
	}
}