Blynk App With GSM Module SIM900A, IOT Project

About: Share Knowledge about Arduino, ESP,GSM,Basic Electronics, DIY PROJECTS, Raspberry pi

Blynk is the most popular app for IOT. this can work with anything : ESP8266, Arduino, Raspberry Pi, SparkFun and Others. In this post we are going to learn how to connect GSM module with Blynk App Using GPRS functionality of GSM module and we will also be controlling LED using Blynk app using GPRS functionality of GSM module.

Components required

Components required for the project are -:

  • Arduino Uno
  • GSM module Sim 900A
  • Bread Board
  • Jumper Wires
  • 12V 2 amp power adapter
  • LED (Use relay if you want to control AC appliances)
  • Blynk App

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Step 1: Search and Get Blynk App From the Browser

  • Search and get Blynk App from the Browser. Open (official website of Blynk).
  • Scroll down and click on download "Blynk Library".
  • You will be directed to the Github page where you can download the library for Blynk. Click and download the zip file.
  • Extract the downloaded zip file and then copy contents of library to the library folder of Arduino IDE and tools to tools folder.
  • Download Blynk app for Android or Ios

Step 2: Start Work With Arduino IDE

  • Open your Arduino IDE. Navigate to File ---> Examples and then go to Blynk.
  • Open Blynk example boards GSM and then open Sim800_Sim900. Modify and use code according to the project.

Step 3: Module Selection and Code Editing

  • Select your Module eg. Sim900A. Uncomment Blynk_HeartBeat and change pin"30" to pin "18".
  • Don't forget to paste token from your Gmail.
  • Uncomment the line if your sim is locked with your pin. Leave it as it is if your sim card is not locked.

Step 4: Working With Blynk App

  • Firstly download Blynk app from playstore. Open app and click on new project and give a name to your project.
  • Choose your device, here we are using Arduino Uno.
  • Select GSM as connection type and theme whether dark or light and click create. An email will be sent to you on your registered email account along with the token.
  • If you click on the "+" icon, there are a lot of steps available here like timer, joystick, LED, LED, gauge etc.
  • If you click on the button to edit, then select "Digital" and then D8 option. Select button as a switch and then we are ready to go.
  • Blynk will send an email which contains tokens for the project. Copy it and paste it to the code and the code is ready to be used.
  • Upload the code to your Arduino board.

Step 5: Connecting LED's (Arduino Uno GSM Module)

  • Make connections accoding to the schematics

Pin 2 ---> TX

Pin 3----> RX

GND ----> GND

Connect LED to digital Pin 8 of Arduino

Step 6: Connect Arduino Board to PC

  • Connect Arduino Board to PC and power the GSM module with power adapter

Step 7: Open Serial Monitor and Check Functioning

  • Open serial monitor and wait till the module is connected to serial monitor.
  • as soon as the code is connected to the module and starts working with the Blynk app, the LED Starts glowing.

Step 8: Where to Buy??

Click here to buy GSM ModuleSim900A

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    4 weeks ago

    great stuff. I wonder why you recommend changing at Blynk_HeartBet from 30 to 18.
    Thank you