Circuit Documentation

Summary

This document provides a detailed overview of a circuit designed using an ESP8266 NodeMCU microcontroller and various sensors. The circuit includes connections to a DHT11 Humidity and Temperature Sensor, an MQ-7 Carbon Monoxide Sensor, an MQ-2 Gas Sensor, and an MQ135 Air Quality Sensor. The ESP8266 NodeMCU serves as the central controller, interfacing with the sensors to collect environmental data.

Component List

ESP8266 NodeMCU

• Description: A low-cost Wi-Fi microcontroller with GPIO, ADC, and other features.
• Pins: D0, D1, D2, D3, D4, 3V3, GND, D5, D6, D7, D8, RX, TX, A0, RSV, SD3, SD2, SD1, CMD, SD0, CLK, EN, RST, VIN

DHT11 Humidity and Temperature Sensor

• Description: A basic, low-cost digital temperature and humidity sensor.
• Pins: VDD, DATA, NULL, GND

MQ-7 Carbon Monoxide Sensor

• Description: A sensor used to detect carbon monoxide levels in the air.
• Pins: VCC, GND, DO, AO

MQ-2 Gas Sensor

• Description: A sensor used to detect various gases including LPG, i-butane, propane, methane, alcohol, hydrogen, and smoke.
• Pins: GND, VCC, ANALOG, Digital

MQ135 Air Quality Sensor

• Description: A sensor used to detect air quality by measuring levels of various gases.
• Pins: VCC, GND, A0, D0

Wiring Details

ESP8266 NodeMCU

• D2 is connected to DATA of the DHT11 Humidity and Temperature Sensor.
• 3V3 is connected to VDD of the DHT11 Humidity and Temperature Sensor.
• GND is connected to GND of the DHT11 Humidity and Temperature Sensor.
• D6 is connected to DO of the MQ-7 Carbon Monoxide Sensor.
• D7 is connected to Digital of the MQ-2 Gas Sensor.
• GND is connected to GND of the MQ-2 Gas Sensor and GND of the MQ-7 Carbon Monoxide Sensor.
• 3V3 is connected to VCC of the MQ-2 Gas Sensor and VCC of the MQ-7 Carbon Monoxide Sensor.
• A0 is connected to A0 of the MQ135 Air Quality Sensor.
• GND is connected to GND of the MQ135 Air Quality Sensor.
• 3V3 is connected to VCC of the MQ135 Air Quality Sensor.

DHT11 Humidity and Temperature Sensor

• DATA is connected to D2 of the ESP8266 NodeMCU.
• VDD is connected to 3V3 of the ESP8266 NodeMCU.
• GND is connected to GND of the ESP8266 NodeMCU.

MQ-7 Carbon Monoxide Sensor

• DO is connected to D6 of the ESP8266 NodeMCU.
• GND is connected to GND of the ESP8266 NodeMCU.
• VCC is connected to 3V3 of the ESP8266 NodeMCU.

MQ-2 Gas Sensor

• Digital is connected to D7 of the ESP8266 NodeMCU.
• GND is connected to GND of the ESP8266 NodeMCU.
• VCC is connected to 3V3 of the ESP8266 NodeMCU.

MQ135 Air Quality Sensor

• A0 is connected to A0 of the ESP8266 NodeMCU.
• GND is connected to GND of the ESP8266 NodeMCU.
• VCC is connected to 3V3 of the ESP8266 NodeMCU.

Code

No code was provided for this circuit.

This document provides a comprehensive overview of the circuit, including a summary, component list, wiring details, and code documentation. The ESP8266 NodeMCU microcontroller interfaces with various sensors to collect environmental data, making it a versatile and powerful component in this circuit.