Port manipulation in avr-c

blinkc.c

/*
 * main.c
 *
 *  Created on: 19 Jan 2014
 *      Author: peter
 */

//#define F_CPU 16000000L
#include <avr/io.h>
#include <util/delay.h>

void iterateLeds()
{
	for (int8_t x = 0; x<8; x++) {
		PORTD = (0x01 << x);
		_delay_ms(100);
	}
}

void cylon()
{
	uint16_t delay = 80;
	for (int8_t x = 0; x <= 7; x++) {
		PORTD = (0x01 << x);
		_delay_ms(delay);
	}
	for (int8_t x = 7; x >= 0; x--) {
		PORTD = (0x01 << x);
		_delay_ms(delay);
	}
}

void ledCountTime() {
	for (int8_t x = 0; x <= 255; x++) {
		PORTD = x;
		_delay_ms(1000);
	}
}

void ledLinePulse()
{
	uint16_t delay = 100;
	for (int8_t x = 0; x <= 7; x++) {
		PORTD |= (0x01 << x);
		_delay_ms(delay);
	}
	for (int8_t x = 7; x >= 0; x--) {
		PORTD &= ~(0x01 << x);
		_delay_ms(delay);
	}

}

void ledPulse()
{
	uint16_t delay = 100;
	int8_t i = 0; // the led to turn off
	for (int8_t x = 0; x <= 7; x++) {
		i = x - 3;
		if (x < 3) {
			i = x + 5;
		}

		PORTD &= ~(0x01 << (i)); // turn off an led
		PORTD |= (0x01 << x); // turn on an led

		_delay_ms(delay);
	}
}

int main(void) {
	/*
    DDRD |= 1<<PD7; // set to output
    while(1) {
        PORTD &= ~(1<<PD7); // LED on
        _delay_ms(250);
        PORTD |= 1<<PD7; // LED off
        _delay_ms(250);
    }
    return 0;
    */

	DDRD = 0xFF; // set all to output
	PORTD = 0; // all off
	while(1) {
		cylon();
		//ledCountTime();
		//ledLinePulse();
		//ledPulse();
	}
	return 0;

}