Rev 409 | Blame | Last modification | View Log | Download
/*********************************************
* 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)
*********************************************/
#include <avr/io.h>
#include <inttypes.h>
#define F_CPU 17000000UL // 1 MHz
#include <avr/delay.h>
/* compatibilty macros for old style */
#ifndef cbi
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#endif
#ifndef sbi
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif
void delay_ms(unsigned int ms)
/* delay for a minimum of <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--;
}
}
/* new style */
int main(void)
{
/* INITIALIZE */
/* enable PC5 as output */
DDRC|= (1<<DDC5);
/* 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<<PC5);
delay_ms(500);
/* set output to 5V, LED off */
PORTC|= (1<<PC5);
delay_ms(500);
}
return(0);
}
// // old style now depricated:
// int main(void)
// {
// // enable PC5 as output
// sbi(DDRC,PC5);
// while (1) {
// // led on, pin=0
// cbi(PORTC,PC5);
// delay_ms(500);
// // set output to 5V, LED off
// sbi(PORTC,PC5);
// delay_ms(500);
// }
// return(0);
// }
// // end of old style