/*********************************************
* 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           : ATMEGA8
* Clock frequency     : Internal clock 1 Mhz (factory default)
*********************************************/

/*******************************************************
060502 Modified for ATmega128

circuit:


  		LED		1 k Ohm
			________________	
		|\ |	|		|
	--------| >|----|		|--------
	|	|/ |	|_______________|	|
	|					|
	|					|
	o					o
	
	+5V					PC5

********************************************************/

#include <avr/io.h>


void delay()
{
  int i, j;
  for (i = 0; i < 10000; i++) for (j = 0; j < 10000; j++);
}


int main(void)
{
  /* INITIALIZE */
  /* enable PC5 as output */
  DDRC|= (1<<DDC5);

  /* PC5 is 5 (see file include/avr/iom128.h) and 1<<PC5 is 00100000 
   * This can also be written as _BV(PC5)*/
  while (1) {
    /* led on, pin=0 */
    PORTC &= ~(1<<PC5);
    delay();
    /* set output to 5V, LED off */
    PORTC|= (1<<PC5);
    delay();
  }
  return(0);
}