title: Arduino sending SmS using sim800l
body: <p>how can i write the phone number to the arduino using Sim800l module...
  the right code is this 
      <code>serialSIM800.write("AT+CMGS=\"+639261001204\"\r\n");</code>
  i want to to change the phone number to String so that i can send any      number...</p>
  
  <pre><code>void send()
   {
       digitalWrite(led, HIGH);
       serialSIM800.begin(9600);
       delay(1000);
       char s1 = "AT+CMGS=\"+";
       char s2= number;
       char s3="\"\r\n"";
       char sms = s1+s2+s3;
       //Set SMS format to ASCII
       serialSIM800.write("AT+CMGF=1\r\n");
       delay(1000);
       //Send new SMS command and message number
       serialSIM800.write(sms);
       delay(1000);
       //Send SMS content
       serialSIM800.write("Your student Go inside the School");
       delay(1000);
       serialSIM800.write((char)26);
       delay(250);
   }
  </code></pre>