horse.c

EBD7312 跑马灯驱动程序 SDT 下调是

/*
 * $Id: horse.c,v 1.3 2003/08/29 06:47:01 ynding Exp $
 *
 * horse.c : horse-race driver
 *
 * Copyright (C) 2003 ynding ( [e-mail] )
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "horse.h"

/* time delay */
void wait(int time)
{
	int i = 0;
	int j = 0;

	for ( i=0;i<time;++i ){
		for ( j=0;j<1000;++j )
			;
	}

	return;
}

/* turn on a led */
void led_on(int index)
{
	unsigned char pb = 0x01;
	PBDDR = pb << index;	/* set PB port as output */

	PBDR = pb << index;
	PBDR &= ~(pb<<index);

	return;
}

/* turn off a led */
void led_off(int index)
{
	unsigned char pb = 0x01;
	PBDDR = pb << index;	/* set PB port as output */

	PBDR = pb << index;
	PBDR |= pb << index;

	return;
}

/* horse-race */
void horse(int interval)
{
	int i = 0;

	for ( i=0;i<8;++i ) {
		led_on(i);
		wait(interval);
		led_off(i);
	}

	wait(interval);

	for ( i=7;i>=0;--i ) {
		led_on(i);
		wait(interval);
		led_off(i);
	}

	wait(interval);

	return;
}