function enviarSMS($nr_tlm, $sms)
{
$serial = new PhpSerial();
$serial->deviceSet("COM6");
//choose COM port
$serial->confBaudRate(9600);
//Choose Bitrate
$serial->deviceOpen('w+');
//Open COM port
$serial->sendMessage("AT" . chr(13));
//Check if is acessible
//read response and check if it can continue
$codigo_at = $serial->readPort();
$verificar = substr($codigo_at, -4);
if (substr($verificar, 0, 2) == 'OK') {
$serial->sendMessage("AT+CMGF=1" . chr(13));
//Prepare to SMS
//read response and check if it may continue
$codigo_at = $serial->readPort();
$verificar = substr($codigo_at, -4);
if (substr($verificar, 0, 2) == 'OK') {
$serial->sendMessage('AT+CMGS="' . $nr_tlm . '"' . chr(13));
//send destination number
$serial->sendMessage($sms . chr(26));
//send SMS text
sleep(5);
//read response and check if the sms was sent
$codigo_at = $serial->readSMS();
$verificar = substr($codigo_at, -4);
if (substr($verificar, 0, 2) == 'OK') {
$resposta = "OK";
} else {
$resposta = "NOK";
}
} else {
$resposta = "NOK";
}
} else {
$resposta = "NOK";
}
$serial->deviceClose();
//close COM port - NEVER FORGET THIS STEP!
return $resposta;
}