431.ESP8266 Multisensor Shield with Node-RED You will learn how to integrate the ESP8266 Multisensor Shield for the Wemos D1 Mini board with Node-RED by following the instructions in this project. An MQTT connection will be established between the ESP8266 Multisensor Shield and a Raspberry Pi that is running Node-RED and the Mosquito MQTT broker.

The Multisensor shield includes a temperature sensor, a motion sensor, a light-dependent resistor (LDR), and a three-pin socket that can be used to connect any output, such as a relay module, for instance. On the same Raspberry Pi that is running Node-RED, we will use the Mosquito broker that has been installed. The broker is in charge of receiving all messages, sorting through those messages to determine who might be interested in them, and then publishing those messages to all of the clients who have subscribed to receive them. Read "What is MQTT and How It Works" if you're interested in finding out more about MQTT. The application known as Node-RED will publish messages (such as "on" or "off") in the topic known as esp8266/output. That particular topic has been subscribed to by the ESP8266. Therefore, it turns the output on or off based on whether it receives the message that contains "on" or "off." The temperature is published on the esp8266/temperature topic, and the luminosity is published on the esp8266/ldr topic. The Node-RED application has been set to receive updates regarding those topics. Therefore, it obtains

readings of the temperature and luminosity, which are shown on a chart and a gauge respectively. In the following picture, you can see an overview of what we'll do in this project. Node-RED has indicated that it is interested in the topic esp8266/motion. When motion is detected, the ESP8266 sends out a publication on that subject. In the text widget of the Node-RED Dashboard, the message "MOTION DETECTED!" appears whenever motion is detected and remains there for ten seconds.

Circuit Diagram;

ESP8266 Wemos D1 Mini - see Highest-Rated ESP8266 Wi-Fi Development Board 1x 5mm LED, 1x 330 Ohm resistor 1x DS18B20 temperature sensor 1x mini-PIR motion sensor 1x light dependent resistor 2x 10k Ohm resistor, 1x relay module Breadboard, A set of jumper wires Getting ready to use the Arduino Software

We will use the Arduino IDE to write the code for the ESP8266. In order to use the Arduino Integrated Development Environment (IDE) to upload code to your ESP8266, you will need to install the ESP8266 add-on (How to Install the ESP8266 Board in Arduino IDE). To be able to run the code on the ESP8266, you will additionally need to install three additional libraries. Installing the PubSubClient Library A client for performing straightforward publish/subscribe messaging with a server that supports the MQTT protocol is made available by the PubSubClient library (basically allows your ESP8266 to talk with Node-RED). Library for PubSubClient clients. Within your Downloads folder, there should be a folder labelled ".zip." After unzipping the.zip folder, you should see a folder labelled pubsubclient-master. Replace the name pubsubclient-master with pubsubclient in the name of your folder. Transfer the pubsubclient folder to the libraries folder that was installed with your Arduino IDE. There is a OneWire library. Within your Downloads folder, you ought to have a.zip folder. After unzipping the.zip folder, you should see a folder labelled "OneWire-master." Change the name of your folder to OneWire from OneWire-master. Copy the OneWire folder and paste it into the libraries folder that was installed with your Arduino IDE. Temperature library located in Dallas

DallasTemperature library. Within your Downloads folder, you ought to have a.zip folder. After unzipping the.zip folder, you should be able to access the Arduino-Temperature-Control-Library-master folder. Change the name of the folder you're working in to DallasTemperature from Arduino-Temperature-Control-Library- master. Copy the DallasTemperature folder and paste it into the libraries folder that was installed with your Arduino IDE. At long last, reopen your Arduino IDE and begin the process of uploading code. Paste the code below into the Arduino Software Installer. The areas of the code that require modifications have detailed comments attached to them. You will need to make changes to the code in order to include your personal SSID, password, and MQTT Broker IP Address (Raspberry Pi IP Address).