Home Automation using IOT – Concept and Working Model

Home Automation using IOT – Concept and Working Model

This note explains the concept of using IOT for home automation. The below diagram shows how home appliances are controlled using a web based control panel. There are three lights(LEDs), one fan and a temperature sensor in the model house. Lights and fan are driven by relay modules. Relays are driven by NodeMCU (ESP8266 based IOT module). The temperature sensor is connected to the nodeMCU directly. We have an IOT server, running MQTT broker and also the web based control panel. Using the control panel buttons, the user can turn on/turn off lights…continue reading →
Touchscreen calculator using Arduino and TFT LCD Display

Touchscreen calculator using Arduino and TFT LCD Display

This time, I have made a calculator with the TFT display and Arduino. This note describes the steps I followed. Required Materials Hardware Arduino board (I've used UNO) TFT Touchscreen display (Must be compatible with Adafruit TFTLCD library) Software Arduino IDE The TFT To know more about how to program a TFT display for Arduino, you may read this note. Calculator Display and Logic Draw buttons for digits and operators and the display field of the calculator. All digits and operator buttons have the same size. So, the co-ordinates of each button can…continue reading →
Connecting a Relay Module with NodeMCU

Connecting a Relay Module with NodeMCU

In this note, let's see how to connect a relay module to a NodeMCU board. We use a relay module when we have to drive devices that use more current than NodeMCU board can supply.   Here's a list of things needed: Hardware NodeMCU v1.0 or v0.9 Relay module - I used a 5V DC 4 channel relay module Some jumper wires Software Arduino IDE (arduino.cc/Downloads) Arduino ESP8266-core (Steps for installation can be found in my other blog. Link Here) Step 1: How does the relay module work? The relay module is an electrical…continue reading →

Mosquitto MQTT Publish – Subscribe from PHP

Looking for the code to connect to Mosquitto broker from your PHP code ? Here's a simple example with step by step instructions. The complete functional code can be downloaded here. Before starting off, you need to have php, Mosquitto broker and Mosquitto library for php installed. If you need guidance on installing Mosquitto library for PHP, do refer my instructions here. The Basic PHP page Let’s start from a simple PHP web page. Our page has only two buttons - one to publish and one to subscribe. Below php file is saved…continue reading →

Mosquitto PHP library on RaspberryPi – Installation

To connect to Mosquitto MQTT broker from your PHP code, you need to have the Mosquitto PHP library module enabled on your server. This post explains steps to get the Mosquitto PHP library installed. These steps have been verified on Ubuntu desktop as well as on RaspberryPi (Raspbian Jessie), running Apache2 and PHP 5.4. You need to be connected to internet to complete these steps. Follow them in the order given. 1. sudo apt-get install php-pear 2. sudo apt-get install php5-dev 3. sudo apt-get install libmosquitto-dev 4. sudo pecl install Mosquitto-alpha NOTE: In…continue reading →
TFT LCD Display shield for Arduino UNO

TFT LCD Display shield for Arduino UNO

This note is an introduction to the 2.4” TFT LCD Display shield for Arduino UNO. Items Used: Hardware Arduino UNO 2.4” TFT LCD touchscreen shield A computer USB cable to connect Arduino to the computer Software Arduino IDE : arduino.cc/Downloads This TFT LCD display can display colour graphics and is a touch sensitive screen. It has an SD card slot too for storing images. This display board can be inserted directly on to the Arduino pins, without using any wires. That’s why it is called a shield.  We can program Arduino to show graphics,…continue reading →
IOT Setup Using ESP8266 and HiveMQ Public MQTT

IOT Setup Using ESP8266 and HiveMQ Public MQTT

  This is a basic Internet of Things (IOT) project using a public MQTT server. I am doing two things here: Control an LED at my home from anywhere in the world, by simply publishing an “on” or “off” command in the browser. Read the temperature inside my room from the browser, wherever I go. Watch a video on NodeMCU and HiveMQ: Following components are used for this project: NodeMCU (an ESP8266 based SoC board), usually used for IOT projects A temperature sensor (LM35) Onboard LED on NodeMCU, that is connected to pin…continue reading →
Arduino powered Remote Controlled Car

Arduino powered Remote Controlled Car

This project note may be a very interesting one for you. It is a remote controlled (RC) car made using an Arduino UNO. Here are some demo videos List of materials Hardware Arduino Uno L293D motor driver board HC-05 bluetooth module Chassis and wheels for the car Some jumper wires A battery pack A computer for programming the Arduino Software Arduino IDE -- arduino.cc/Downloads The android app to controll the car -- https://play.google.com/store/apps/details?id=braulio.calle.bluetoothRCcontroller Arduino is a platform which is very useful for creating many electronics projects. The HC-05 is a bluetooth tranceiver module.…continue reading →