Circuit Documentation

Summary

This document provides a detailed overview of a circuit that includes an ESP32 microcontroller, an MQ-5 gas sensor, multiple HX711 bridge sensor interfaces, and load cells. The circuit is designed to interface with various sensors and process their data using the ESP32 microcontroller.

Component List

1. ESP32 (30 pin)

   • Description: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
   • Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, Vin, D23, D22, TX0, RX0, D21, D19, D18, D5, TX2, RX2, D4, D2, D15, 3V3

2. MQ-5

   • Description: A gas sensor used to detect LPG, natural gas, and coal gas.
   • Pins: VCC, GND, Digi Out, Analog out

3. HX711 - Bridge Sensor Interface

   • Description: An interface for load cells to measure weight.
   • Pins: E+, E-, A-, A+, B-, B+, GND - GROUND, DATA (OUT), SCK - CLOCK (IN), 3.3/3.5V Supply

4. Load Cell - Red/white/black/green

   • Description: A sensor used to measure weight.
   • Pins: E+, A-, E-, A+

Wiring Details

ESP32 (30 pin)

• GND is connected to:

  • GND of MQ-5
  • GND - GROUND of HX711 (3 instances)

• 3V3 is connected to:

  • VCC of MQ-5
  • 3.3/3.5V Supply of HX711 (3 instances)

• D34 is connected to:

  • Analog out of MQ-5

• D22 is connected to:

  • SCK - CLOCK (IN) of HX711 (1 instance)

• D21 is connected to:

  • DATA (OUT) of HX711 (1 instance)

• D19 is connected to:

  • SCK - CLOCK (IN) of HX711 (1 instance)

• D18 is connected to:

  • DATA (OUT) of HX711 (1 instance)

• TX2 is connected to:

  • SCK - CLOCK (IN) of HX711 (1 instance)

• RX2 is connected to:

  • DATA (OUT) of HX711 (1 instance)

MQ-5

• GND is connected to:

  • GND of ESP32 (30 pin)
  • GND - GROUND of HX711 (3 instances)

• VCC is connected to:

  • 3V3 of ESP32 (30 pin)
  • 3.3/3.5V Supply of HX711 (3 instances)

• Analog out is connected to:

  • D34 of ESP32 (30 pin)

HX711 - Bridge Sensor Interface

• GND - GROUND is connected to:

  • GND of ESP32 (30 pin)
  • GND of MQ-5

• 3.3/3.5V Supply is connected to:

  • 3V3 of ESP32 (30 pin)
  • VCC of MQ-5

• SCK - CLOCK (IN) is connected to:

  • D22 of ESP32 (30 pin) (1 instance)
  • D19 of ESP32 (30 pin) (1 instance)
  • TX2 of ESP32 (30 pin) (1 instance)

• DATA (OUT) is connected to:

  • D21 of ESP32 (30 pin) (1 instance)
  • D18 of ESP32 (30 pin) (1 instance)
  • RX2 of ESP32 (30 pin) (1 instance)

• E+ is connected to:

  • E+ of Load Cell (3 instances)

• A+ is connected to:

  • A+ of Load Cell (3 instances)

• A- is connected to:

  • A- of Load Cell (3 instances)

• E- is connected to:

  • E- of Load Cell (3 instances)

Load Cell - Red/white/black/green

• E+ is connected to:

  • E+ of HX711 (3 instances)

• A+ is connected to:

  • A+ of HX711 (3 instances)

• A- is connected to:

  • A- of HX711 (3 instances)

• E- is connected to:

  • E- of HX711 (3 instances)

Code

No code is provided for this circuit.

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This document provides a comprehensive overview of the circuit, including the components used and their interconnections. This should serve as a useful reference for understanding and troubleshooting the circuit.