Circuit Documentation

Summary of the Circuit

This circuit integrates a NodeMCU V3 ESP8266 microcontroller with a set of sensors including the KY-015 DHT11 temperature and humidity sensor, the MQ-2 gas sensor, and the MQ135 air quality sensor. The NodeMCU V3 ESP8266 serves as the central processing unit, interfacing with the sensors to monitor environmental conditions. The sensors are powered by the NodeMCU and send their data back to it for processing.

Component List

NodeMCU V3 ESP8266

• Description: A WiFi-enabled microcontroller compatible with the Arduino platform.
• Pins: A0, GND, VU, S3, S2, S1, SC, S0, SK, 3V3, EN, RST, Vin, D0, D1, D2, D3, D4, D5, D6, D7, D8, RX, TX

KY-015 DHT11 Temperature and Humidity Sensor

• Description: A basic, low-cost digital temperature and humidity sensor.
• Pins: 5V, S, GND

MQ-2 Gas Sensor

• Description: A sensor for detecting LPG, i-butane, propane, methane, alcohol, hydrogen, and smoke.
• Pins: VCC, GND, A0, D0

MQ135 Air Quality Sensor

• Description: A sensor for detecting a wide range of gases, including NH3, NOx, alcohol, benzene, smoke, and CO2.
• Pins: VCC, GND, A0, D0

Wiring Details

NodeMCU V3 ESP8266

• A0 connected to MQ135 A0
• D1 connected to KY-015 DHT11 S
• D2 connected to MQ-2 SENSOR D0
• D3 connected to KY-015 DHT11 5V
• D4 connected to KY-015 DHT11 GND
• GND connected to MQ135 GND and MQ-2 SENSOR GND
• 3V3 connected to MQ135 VCC and MQ-2 SENSOR VCC

KY-015 DHT11 Temperature and Humidity Sensor

• S connected to NodeMCU D1
• 5V connected to NodeMCU D3
• GND connected to NodeMCU D4

MQ-2 Gas Sensor

• VCC connected to NodeMCU 3V3
• GND connected to NodeMCU GND
• D0 connected to NodeMCU D2

MQ135 Air Quality Sensor

• VCC connected to NodeMCU 3V3
• GND connected to NodeMCU GND
• A0 connected to NodeMCU A0

Documented Code

No code has been provided for the microcontrollers in the circuit. To fully utilize the circuit, embedded code for the NodeMCU V3 ESP8266 is required to initialize the sensors, read data from them, and perform any necessary processing or communication tasks.