#include <avr/io.h>
#include <util/delay.h>
#define F_CPU20000UL
#define LED_BLUE_PORT PORTA 


int main (void){
  DDRA = 0b111110111;  //set PORTA3 for input

while (1){
      
      LED_BLUE_PORT = 0b10000000;  //set PORTA.7 high
      

      _delay_ms(1000);

      LED_BLUE_PORT = 0b00000000;  //set PORTA.7 low
      

      _delay_ms(1000);
  }

}