SendSMS.ino

/*********************************************************************************************************************************
  SendSMS.ino

  For ESP8266, ESP32, SAMD21/SAMD51, nRF52, SAM DUE, Teensy and STM32 with GSM modules

  GSM_Generic is a library for the ESP8266, ESP32, SAMD21/SAMD51, nRF52, SAM DUE, Teensy and STM32 with GSM modules

  Based on and modified from MKRGSM Library (https://github.com/arduino-libraries/MKRGSM)

  Built by Khoi Hoang https://github.com/khoih-prog/GSM_Generic
  Licensed under GNU Lesser General Public License

  Copyright (C) 2017  Arduino AG (http://www.arduino.cc/)
  This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation, either version 2.1 of the License, or (at your option) any later version.
  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  You should have received a copy of the GNU General Public License along with this program.
  If not, see <https://www.gnu.org/licenses/>.
 **********************************************************************************************************************************/
/*
  SMS sender

  This sketch, for the GSM module, sends an SMS message you enter in the serial monitor. Connect your Arduino with the
  GSM shield and SIM card, open the serial monitor, and wait for the "READY" message to appear in the monitor. Next, type a
  message to send and press "return". Make sure the serial monitor is set to send a newline when you press return.

  Circuit:
   GSM Module
   Antenna
   SIM card that can send SMS

  created 25 Feb 2012
  by Tom Igoe
*/

#include "defines.h"

// Please enter your sensitive data in the Secret tab or arduino_secrets.h
// PIN Number
const char PINNUMBER[] = SECRET_PINNUMBER;

// BaudRate to communicate to GSM/GPRS modem. If be limit to max 115200 inside modem
unsigned long baudRateSerialGSM  = 115200;

// initialize the library instance
GSM gsmAccess;
GSM_SMS sms;

/*
  Read input serial
*/
int readSerial(char result[]) 
{
  int i = 0;
  
  while (1) 
  {
    while (Serial.available() > 0) 
    {
      char inChar = Serial.read();
      
      if (inChar == '\n') 
      {
        result[i] = '\0';
        Serial.flush();
        return 0;
      }
      
      if (inChar != '\r') 
      {
        result[i] = inChar;
        i++;
      }
    }
  }
}

void setup()
{
  // initialize serial communications and wait for port to open:
  Serial.begin(115200);
  while (!Serial);

  delay(200);

  Serial.print(F("\nStarting SendSMS on ")); Serial.println(BOARD_NAME);
  Serial.println(GSM_GENERIC_VERSION);

#if ( defined(DEBUG_GSM_GENERIC_PORT) && (_GSM_GENERIC_LOGLEVEL_ > 4) )
  MODEM.debug(DEBUG_GSM_GENERIC_PORT);
#endif

  // connection state
  bool connected = false;

  // Start GSM shield
  // If your SIM has PIN, pass it as a parameter of begin() in quotes
  while (!connected) 
  {
    if (gsmAccess.begin(baudRateSerialGSM, PINNUMBER) == GSM_READY) 
    {
      connected = true;
    } 
    else 
    {
      Serial.println("Not connected");
      delay(1000);
    }
  }

  Serial.println("GSM initialized");
}

void loop() 
{
  Serial.print("Enter a mobile number: ");
  char remoteNum[20];  // telephone number to send sms
  readSerial(remoteNum);
  Serial.println(remoteNum);

  // sms text
  Serial.print("Now, enter SMS content: ");
  char txtMsg[200];
  readSerial(txtMsg);
  Serial.println("SENDING");
  Serial.println();
  Serial.println("Message:");
  Serial.println(txtMsg);

  // send the message
  sms.beginSMS(remoteNum);
  sms.print(txtMsg);
  sms.endSMS();
  Serial.println("\nCOMPLETE!\n");
}