GPIO toggle in AVR8 native code

gpio.c

/**
 * Toggle GPIO port PB1 (Arduino port 9)
 * 
 * Note: This code only works with 
 * AVR 8-bit family micro-controllers
 */

#include <avr/io.h>

int main(void)
{
    // Set port as output
    DDRB |= (1 << PB1);

    while (1)
    {
        // Toggle output
        PINB |= (1 << PB1);
    }
    
    return 0;
}