ESP8266 In this project, we will use the BME680 Sensor with the ESP8266 to measure the quality of the air inside using the BSEC Library and the Blynk Application, which is an IoT Cloud platform. Earlier, we made an Indoor Environment Monitoring System with ESP32 and a TFT Color LCD Screen. We learned about the BME680 integrated Environmental Sensor in projects we did before. First, we connected BME680 to Arduino and made a simple

project for a weather station. Also, we used an ESP32 and a BME680 sensor to make an IoT-based Weather Station. We used the Ubidots MQTT Platform to keep an eye on the weather. But one problem with the project was that we could only measure things like temperature, humidity, pressure, altitude, dew point, and gas resistance. We couldn't figure out the IAQ Value, which stands for the Index of Air Quality. We couldn't even get a reading for the same amount of CO2 and a percentage of VOCs. In this article, we will use the BSEC library, which stands for Bosch Sensortec Environment Cluster and is a very advanced BME680 library. Using this library, we can find the value of Indoor Air Quality (IAQ) as well as the equivalent amount of carbon dioxide or Total Volatile Organic Compound (TVOC). The Blynk Cloud platform is used to keep an eye on data about the environment from afar. The ESP8266 connects to the WiFi network and sends data to the Blynk server on a regular basis. So, we can use the BME680 sensor with the ESP8266 to check the quality of the air inside on the Blynk app. BME680 Integrated Environmental Sensor The BME680 is a digital 4-in-1 sensor that can measure gas, humidity, pressure, and temperature using tried-and-true methods. The BME680 is a

better and more advanced version of the BMP180, BMP280, and BME280. The BME680's gas sensor can pick up on a wide range of volatile organic compounds to check the quality of the air inside. The sensor is very accurate and has a high degree of linearity. The BME680 was made especially for mobile applications and wearables that need to be small and use little power. The BME680's gas sensor can pick up a wide range of gases, such as volatile organic compounds, to measure the quality of the air (VOC). Between 1.7V and 3.6V, the sensor works. This module uses between 0.29 and 0.8 uA of power when it's not being used. When it's in sleep mode, it uses between 0.15 and 1 uA. The BME680 Sensor is able to measure temperatures from -40°C to +85°C. And the range of the humidity measurement is from 0 to 100%. The Air quality index (IAQ) can be measured from 0 to 500 PPM. The sensor's I2C Address is set to 0x76 by default, but you can change it to 0x77 by connecting SDO to GND. Circuit: Interfacing BME680 with ESP8266

Wemos D1 Mini Board is the main thing that is used in this project. NodeMCU Board is another option. All of these boards have an ESP8266- 12E Chip, which is a fast, 32-bit controller with a lot of features. The chip has a WiFi chip built in that can use a WiFi Network to send the data to the internet or a server. Here is a diagram of how to connect a BME680 sensor to a Wemos D1 Mini or ESP8266. Connect the SCL and SDA pins of the BME680 to D4 and D3 on the Wemos Board. Supply the sensor as 3.3V VCC through 3.3V Pin of Wemos Board. Link the SDO to the GND. It's important to connect the BME680's SDO pin to GND because the original code was written to use a different I2C address (0x77). If you connect the SDO pin of the BME680 sensor to Ground, you can get to this I2C address. You can test this connection on a breadboard or on a PCB Board that you made yourself. For testing the circuit, I like to use a breadboard connection. Go to the "Tools" menu and pick "Wemos D1 Board" from the list. If you are using NodeMCU Board, you can also choose it from the list. Then,

choose the COM port and click the upload button to send the code to the board. Now, you can open the Serial Monitor, The following parameters will be

1. Millisecond time stamp 2. Temperature in °C (raw) 3. Pressure in millibars 4. Rough Relative Humidity in Percent 5. The gas sensor's raw data is given as a resistance value in Ohm. 6. IAQ index 7. IAQ Accuracy (begins at 0 after startup, goes to 1 after a few minutes, and reaches 3 when the sensor is calibrated). 8. Temperature in degrees Celsius 9. Relative Humidity in Percent 10. Fixed IAQ 11. CO2 equivalent (estimation of the CO2 equivalent in ppm in the environment) 12. Breath VOC equivalent output (estimates the total VOC concentration in ppm in the environment) Once the readings from the BME680 sensor are stable, you can check the right values for IAQ, CO2, and VOC.

Now we need to set up the Blynk application so that we can get the BME680 Sensor data from the ESP8266. This Blynk app is used to monitor the quality of the air inside for BME680. Blynk is an app that can be used on both Android and IOS devices to keep an eye on any IoT-based app. It

lets you make your own graphical user interface for an Internet of Things app. Here, we'll show you the IoT Indoor Air Quality Data on the Blynk App. So get the Blynk app from the Google Play Store and install it. The App Store has downloads for people who use IOS. Once the app is installed, open it and sign up using your email address and password. Make a new project from the dashboard and choose NodeMCU Board & Wifi Connection. Then, you can drag and drop or add six widgets, assign the variable according to the code, and email the authentication code. You will get a letter in the mail with the code. Copy this code to prove who you are. This is something your code will need. Indoor Air Quality Monitoring using BME680 & ESP8266 on Blynk

With the SSID and password given, the ESP8266 Board will try to connect to the wifi network. Every 3 seconds, the data from the BME680 IAQ is sent to the Blynk application. Both Serial Monitor and Blynk Application can be used to look at the data. Every time the sensor sends some values, the data changes. Here will be the lovely gauge for pressure, temperature, humidity, IAQ, CO2, and VOC. This is how you can use BME680 and ESP8266 to check the quality of the air inside and outside. It's a nice and easy way to keep track of the air quality on Blynk Cloud.