Circuit Documentation

Summary

This circuit involves a NodeMCU V3 ESP8266 microcontroller interfaced with an MQ-2 gas sensor, an MKE-S14 DHT11 temperature and humidity sensor, and an LCD screen (16x2) with I2C interface. The NodeMCU serves as the central controller, reading data from the sensors and displaying the information on the LCD screen.

Component List

1. NodeMCU V3 ESP8266

   • Description: A low-cost Wi-Fi microcontroller with multiple GPIO pins.
   • 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

2. MKE-S14 DHT11 Temperature And Humidity Sensor

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

3. MQ-2 Gas Sensor

   • Description: A sensor for detecting gas leaks (e.g., LPG, i-butane, propane, methane, alcohol, hydrogen, smoke).
   • Pins: GND, VCC, ANALOG, Digital

4. LCD screen 16x2 I2C

   • Description: A 16x2 character LCD display with I2C interface.
   • Pins: SCL, SDA, VCC, GND

Wiring Details

NodeMCU V3 ESP8266

• A0: Connected to MQ-2 (ANALOG)
• GND: Connected to MQ-2 (GND), LCD screen (GND), DHT11 (GND)
• 3V3: Connected to MQ-2 (VCC), LCD screen (VCC), DHT11 (5V)
• D1: Connected to LCD screen (SCL)
• D2: Connected to LCD screen (SDA)
• D4: Connected to DHT11 (SIG)

MKE-S14 DHT11 Temperature And Humidity Sensor

• SIG: Connected to NodeMCU (D4)
• 5V: Connected to NodeMCU (3V3)
• GND: Connected to NodeMCU (GND)

MQ-2 Gas Sensor

• ANALOG: Connected to NodeMCU (A0)
• VCC: Connected to NodeMCU (3V3)
• GND: Connected to NodeMCU (GND)

LCD screen 16x2 I2C

• SCL: Connected to NodeMCU (D1)
• SDA: Connected to NodeMCU (D2)
• VCC: Connected to NodeMCU (3V3)
• GND: Connected to NodeMCU (GND)

Code

No code provided for this circuit.

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This documentation provides a comprehensive overview of the circuit, including a summary, detailed component list, wiring details, and a section for code (if any). The components are clearly separated to ensure readability and ease of understanding.