serial communication problem

Projects Programming
13

Some copy/paste mods

//zoomkat 3-5-12 simple delimited ',' string parce 
//from serial port input (via serial monitor)
//and print result out serial port
// CR/LF could also be a delimiter

int ledPin = 13;
String readString;

void setup() {
  Serial.begin(9600);
  pinMode(ledPin, OUTPUT); 
  Serial.println("serial LED on/off test with , delimiter"); // so I can keep track
}

void loop() {

  if (Serial.available())  {
    char c = Serial.read();  //gets one byte from serial buffer
    if (c == ',') {
      if (readString.length() >0) {
        Serial.println(readString); //prints string to serial port out
        //do stuff with the captured readString
        if(readString.indexOf("on") >=0)
        {
          digitalWrite(ledPin, HIGH);
          Serial.println("LED ON");
        }
        if(readString.indexOf("off") >=0)
        {
          digitalWrite(ledPin, LOW);
          Serial.println("LED OFF");
        }       
        readString=""; //clears variable for new input
      }
    }  
    else {     
      readString += c; //makes the string readString
    }
  }
}