   if (Serial.available() > 0)
   {
     digitalWrite(ActivityLED, HIGH);      // signal activity detected
+    SerialRequestCounter += 1;            // For debugging purposes
 
     ActionRequest = serialRX();           // check the input
 

byte ds1w_addr[8];
byte ds1w_data[12];

void setup()
{
  pinMode(ActivityLED, OUTPUT);     // An LED to signal activity
  digitalWrite(ActivityLED, HIGH);      // Turn the LED on during setup()
  Serial.begin(9600);               // Initialise serialport
  Serial.print("... ");


        Value = readDSTemperature();
        Serial.print(Value);
        break;
      case 'Z':
      case 'z':
        // Number of serial requests
        // For debugging purposes
        Serial.print(SerialRequestCounter);
        break;
      default:
        Serial.print("NaN");          // Invalid ActionRequest returns `NaN`
        break;
