#include <avr/io.h>
#include <util/delay.h>
 
 
int main (void)
{
  // set PA7 to be output
  // set PA3 to be Input
  DDRA = 0b10000000;
  
  
  while (1) {
    if (!(PINA & 0b00001000))
    // Read pin 7

{ 
    
    // set PA3 high
    PORTA = 0b10000000; 
    _delay_ms(20);
    // set PA3 low
    PORTA = 0b00000000;
    _delay_ms(20);

    
    // set PA3 high
    PORTA = 0b10000000; 
    _delay_ms(200);
    // set PA3 low
    PORTA = 0b00000000;
    _delay_ms(200);
  }
  }
  return 1;
}