arduino gsm IOT project with sim 800l gsm module


GSM IOT Project using sim 800l

gsm module






GSM IOT project using sim 800l GSM module
we can control 8 channel relay module by pressing 1-8 numbers of the dial pad and receiving an SMS state of each relay switch we can control any DC or AC device including Lights fans water pumps etc

 

ABOUT THIS PROJECT

In this project we are building a home IOT system that we can control home appliances, using a simple GSM-based, just by taking a call using a phone. In this project, no Smartphone is needed, just the old GSM phone will work to switch ON and OFF


When we take a call to this system it automatically answers the call after that we can control 8 relays by pressing the keypad buttons of our mobile phone. if we press the no1 button system will switch on Relay 1, if we press the 1 button again system will switch off  Relay 1, each button uses as a toggle key so we can control 8 Relays using 1-8  keys of our mobile phone.

 

How It Works

The operating principle of this tutorial is very simple: In this project, We use DTMF technology to identify the button which we pressed

DTMF is used for telecommunication signaling over analog telephone lines in the voice-frequency band between telephone handsets, other communications devices, and the switching center.


With DTMF, each key we press on our phone generates two tones of specific frequencies. So that human voice can't imitate the tones, this tone is generated from a high-frequency group of tones and the other from a low-frequency group. Here are the signals you send when you press your dial-pad tone  phone keys:



gsm module also can send and receive these DTMF tones  then Arduino can filter the DTMF data that received to gsm module





Required Components:

Arduino  Uno  or Arduino Nano

mic

buzzer

GSM module: The GSM module we use is SIM 800L

8-Channel Relay Module: The 8-Channels Relay module’s operating voltage is 5V DC with a drive current of 20mA


Setup

The setup to use this code is very simple. You just have to:


  1. Plug a micro SIM card into your sim 800l or any other GSM module
  2. Connect the GSM module and other parts as shown in the diagram
  3. Plug the battery into the board
  4. Plug the micro USB cable and connect it to your PC
  5. Load the code on the board using the Arduino IDE
  6. Call the board and enjoy pressing buttons on your keyboard!

     Download diagram


     Download the GSM IOT code


     Download ATCMD code