Ethernet Sheild Canundrum

Projects Programming
8

Also, pins 0 and 1 are your serial connection via the USB port. You're not going to want to mess with those either.

btw, loops are your friend.

#define PIN_COUNT 5
int pins[PIN_COUNT] = {2,3,4,5,7};

for (int i = 0; i< PIN_COUNT; i++)
{
  digitalWrite(pins[i], HIGH);
}

it's the same as putting digitalWrite 5 times.

For example, this disaster here:

  if(response.indexOf("INACTIVE") > 0)  {
        //if(flag == 1)  {
          Serial.println("LIGHTS OFF");
          digitalWrite(0, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(1, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(2, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(3, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(4, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(5, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(6, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(7, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(8, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(9, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(10, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(11, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(12, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(13, LOW);   // turn the LED on (HIGH is the voltage level)
          flag = 0;
        //}
    }
    else  {
        //if(flag == 0)  {
          Serial.println("LIGHTS ON.");
                   digitalWrite(0, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(1, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(2, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(3, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(4, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(5, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(6, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(7, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(8, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(9, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(10, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(11, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(12, LOW);   // turn the LED on (HIGH is the voltage level)
          digitalWrite(13, LOW);   // turn the LED on (HIGH is the voltage level)
          flag = 1;
        //}
    }

Can be re-written as:

#define PIN_COUNT 5
int pins[PIN_COUNT] = {2,3,4,5,7};
 bool inactive  = ( response.indexOf("INACTIVE") == -1);
 for (int i = 0; i < PIN_COUNT; i++)
{
  digitalWrite(pins[i], inactive);
}

Serial.print("LIGHTS ");
Serial.println(inactive ? "ON" : "OFF");

Disclaimer: Haven't tried to compile or test any of the above.