Do nothing while programming?

Hi, I have to control UNO using sim 900 shield,

pls help me to write program If I send the message it should not do anything while receiving next message. After receiving next message It have to go for void loop and have to do something.

Exactly I need button read should not work if send the message 'Off'

while I send the message 'On' like that. Thank u

I need to work on this program

Hi, I have to control UNO using sim 900 shield, 


pls help me to write program If I send the message it should not do anything while receiving next message. After receiving next message It have to go for void loop and have to do something. 


Exactly I need button read should not work if send the message 'Off'


while I send the message 'On' like that. Thank u


I need to work on this program/*
  Button
 
 Turns on and off a light emitting diode(LED) connected to digital  
 pin 13, when pressing a pushbutton attached to pin 2. 
 
 
 The circuit:
 * LED attached from pin 13 to ground 
 * pushbutton attached to pin 2 from +5V
 * 10K resistor attached to pin 2 from ground
 
 * Note: on most Arduinos there is already an LED on the board
 attached to pin 13.
 
 
 created 2005
 by DojoDave <http://www.0j0.org>
 modified 28 Oct 2010
 by Tom Igoe
 
 This example code is in the public domain.
 
 http://www.arduino.cc/en/Tutorial/Button
 */

// constants won't change. They're used here to 
// set pin numbers:
const int buttonPin = 2;     // the number of the pushbutton pin
const int ledPin =  13;      // the number of the LED pin

// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status

void setup() {
  // initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT);      
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT);     
}

void loop(){
  // 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 == HIGH) {     
    // turn LED on:    
    digitalWrite(ledPin, HIGH);  
  } 
  else {
    // turn LED off:
    digitalWrite(ledPin, LOW); 
  }
}
  1. please follow the quide lines how to post code ...
  2. Please take some time to make your requirements more explicit (as for me these are quite vague)

OK sir sure

Venki:
Exactly I need button read should not work if send the message 'Off'

does the program has to wait until the ON command come?

does the program has to wait until the ON command come?

yes sir, when I send on then only it have to go void loop.

thank you

you can try something like this...

void setup(){
  Serial.begin(9600);//start the serial communication
  serial_check();
}//end of setup

void loop(){
//you can do your stuff here
}//end of loop

void serial_check(){
  Serial.println("Please enter 1 to stay in loop 0 to exit loop");
  while(!Serial.available()){
    //wait until user enters the data
  }//end of while

    while(Serial.available()){
    char in_char = Serial.read();
    if (in_char == 1){
      Serial.println("you entered 1 exiting loop");
    }
    else if(in_char == 0){
      Serial.println("You entered 0");
      serial_check();// call the function again to prompt the user
    }
    else{
      Serial.println("you entered Wrong Character");
      serial_check();// call the function again to prompt the user

    }//end of else

  }//end of while

}//end of serial_check() function

use 1 for ON and 0 for OFF

Yes sir it makes me on sense, thank u for your kind help