Arduino stop the loop i have a problem with my code, i basically move a motor with the help of 3 relays, when a sensor does not detect the presence of an object part of a call, everything works perfectly, if it was after having called the function CHIAMATA() the arduino loop() stop unexplains, i certainly made a mistake, but i do not understand which.

thanks for your help
this is the code....

#include &lt;swRTC.h&gt;
#include &lt;SoftwareSerial.h&gt;
#include &lt;String.h&gt;

swRTC rtc; //create a new istance of the lib
SoftwareSerial mySerial(3, 2);

const int buttonPin = 19;
const int sensorPin = 9;
const int allarmPin =  13;

int buttonState = 0;
int sensorState = 0;
int relay1 = 8;
int relay2 = 7;
int relay3 = 6;
int var = 0;



// initialize the stepper library on pins 8 through 11:

void setup() {
    rtc.stopRTC(); //stop the RTC
    rtc.setTime(12,0,0); //set the time here
    rtc.setDate(4,6,2012); //set the date here
    rtc.startRTC(); //start the RTC
  Serial.begin(19200); //choose the serial speed here
  mySerial.begin(19200);
  pinMode(allarmPin, OUTPUT);
}



void loop() {


while(mySerial.available()!=0);{}delay(10);

    Serial.print(rtc.getHours(), DEC);
    Serial.print(":");
    Serial.print(rtc.getMinutes(), DEC);
    Serial.print(":");
   Serial.print(rtc.getSeconds(), DEC);
    Serial.println(" ");



//stato riserva croccantini
sensorState = digitalRead(sensorPin);

if (sensorState == HIGH) {
    // turn LED on:
    digitalWrite(allarmPin, HIGH);
    Serial.println("Croccantini esauriti");
    Serial.println("Spia allarme ACCESA");
    Serial.println("Tramoggia DISABILITATA");
    Serial.println("Imposto la chiamata");
    while(sensorState == HIGH) {CHIAMATA(); break;}
  } else {
    // turn LED off:
    digitalWrite(allarmPin, LOW);
    Serial.println("Croccantini OK");
  }
if (sensorState == LOW &amp;&amp; rtc.getHours()== 12 &amp;&amp; rtc.getMinutes()== 00 &amp;&amp; rtc.getSeconds()== 5) {startmotor();}
  //start manuale carico/scarico
  // read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);
  // check if the pushbutton is pressed.
  // if it is, the buttonState is HIGH:
    if (buttonState == 1) {
      Serial.print("Pulsante alimentazione manuale ATTIVO");                           
    // turn on:
  // singlestartmotor();
  }   

      }

void startmotor(){
//numero di cicli di carico da eseguire (5)
 while(var &lt; 5){
 pinMode(relay1, OUTPUT);
  pinMode(relay2, OUTPUT);
    pinMode(relay3, OUTPUT);

 digitalWrite(relay3, LOW); //ABILITA TUTTO
 //AVANTI
 digitalWrite(relay1, LOW);
 digitalWrite(relay2, LOW);
 Serial.print("AVANTI");
 delay(1000); // wait 2 seconds

 digitalWrite(relay3, HIGH);//STOP TUTTO
 digitalWrite(relay1, HIGH);
 digitalWrite(relay2, HIGH);
 delay(1000); //ATTESA PER INVERSIONE MARCIA

 //INDIETRO
 digitalWrite(relay3, LOW);//ABILITA TUTTO
 digitalWrite(relay1, HIGH);
 digitalWrite(relay2, HIGH);
 Serial.print("INDIETRO");
 delay(1000); // wait 2 seconds

  digitalWrite(relay3, HIGH);//STOP TUTTO
  delay(5000); // wait 2 seconds

  var++;
}}

void CHIAMATA() {
 mySerial.println("ATD329xxxxx135;");//dial the number, xxxx ix the phone number.
 delay(100);
 Serial.print("Chiamata in corso..."); return loop();}
Don't do return loop(); With that you enter into a never ending recursion. No system can resist that.

See: return loop(); means "evaluate loop() and return whatever it returns". Well, loop is void; it doesn't return anything.

Even worse is the recursion problem: you call loop(), which calls CHIAMATA, which calls loop ... never ending. You blow out the stack.

I don't look any further than that. Probably there are more errors.