#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>


#define blink_delay 10

#define bit_mask(x) (1 << (x)) // indexes, bit mask, this is similar to  _BV(x)??
#define check_bit(x,b) x&b // checks the bit 0?1?
#define set_bit(x,b) x|=b; // sets the bit
#define clear_bit(x,b) x&=~b; // sets the bit oppisite to the bit
#define flip_bit(x,b) x^=b; // flip


// pin info

// led = Pin10 = PA3(ADC3/T0/PCINT3)
#define led_pin 3
// button = Pin 6 = PA7(PCINT7/ICP/OC0B/ADC7)
#define button_pin 7

// first readed Dan's class page
// http://fab.cba.mit.edu/classes/863.14/people/dan_chen/embedded-programming/index.html
// but he seems to connect the button to a PB pin....
// I looked around other attempts and found this code readable
// http://fab.cba.mit.edu/classes/863.14/people/sarah_edris/files/week07/hello.ftdi.44.echo.c


int main(void){

  set_bit(DDRA,bit_mask(led_pin)) // sets direction of the led_pin of port A as output
  clear_bit(DDRA,bit_mask(button_pin)) // sets direction of the button_pin of port A as input

  // Looping forever
  while(1){
    if(check_bit(PINA,bit_mask(button_pin))){
      clear_bit(PORTA,bit_mask(led_pin))
    }else{
      set_bit(PORTA,bit_mask(led_pin))
    }
  }
  return 1;
}