/*********************************************
* vim: set sw=8 ts=8 si :
* Author: Guido Socher, Copyright: GPL 
* This program is to test the led connected to
* PC5. 
* See http://linuxfocus.org/English/November2004/
* for details.
* Chip type           : ATMEGA644
* Clock frequency     : Internal clock 1 Mhz (factory default)
*********************************************/
#include <avr/io.h>
#include <inttypes.h>
#define F_CPU 16000000UL  // 8 MHz
#include <util/delay.h>

#define LED PINC5

void cekej(int ms)
{

	// we use a calibrated macro. This is more
	// accurate and not so much compiler dependent
	// as self made code.
	while (ms)
	{
		_delay_ms(0.96);
		ms--;
	}
}

int main(void)
{
          /* INITIALIZE */
          /* enable PC5 as output */
          DDRC|= (1<<LED);

          /* PC5 is 5 (see file include/avr/iom8.h) and 1<<PC5 is 00100000 
	   * This can also be written as _BV(PC5)*/
          while (1) {
                      /* led on, pin=0 */
                      PORTC|= (1<<LED);
                      cekej(1000);
                      /* set output to 5V, LED off */
                      PORTC &= ~(1<<LED);
                      cekej(100);
	}
	  return(0);
}