GSM IOT Project using sim 800l
.PNG)
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:
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:
- Plug a micro SIM card into your sim 800l or any other GSM module
- Connect the GSM module and other parts as shown in the diagram
- Plug the battery into the board
- Plug the micro USB cable and connect it to your PC
- Load the code on the board using the Arduino IDE
- Call the board and enjoy pressing buttons on your keyboard!