Circuit Documentation

Summary

This circuit integrates various sensors and modules with an Arduino Nano through an I/O Expansion Shield designed for the Arduino Nano. The circuit is capable of reading air quality data from an MQ135 sensor and temperature and humidity data from a DHT11 sensor. Additionally, it includes a Micro SD Card Module for data logging purposes. The Arduino Nano serves as the central processing unit, interfacing with the sensors and the SD card module to collect and store data.

Component List

DHT11

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

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, DO, A0

Micro SD Card Module

• Description: A module that allows micro SD cards to be read and written via SPI.
• Pins: cs, sck, mosi, miso, vcc, gnd

I/O Expansion Shield For Arduino Nano

• Description: An expansion shield that provides easy access to the pins of an Arduino Nano for quick prototyping.
• Pins: Multiple analog and digital pins, power rails, and communication lines.

Arduino Nano

• Description: A small, complete, and breadboard-friendly board based on the ATmega328 (Arduino Nano 3.x).
• Pins: D1/TX, D0/RX, RESET, GND, D2 to D13, VIN, 5V, A0 to A7, AREF, 3V3

Wiring Details

DHT11

• DATA connected to I/O Expansion Shield (D2)
• GND connected to I/O Expansion Shield (GND)
• VCC connected to I/O Expansion Shield (5V)

MQ135 Air Quality Sensor

• A0 connected to I/O Expansion Shield (A0-S)
• VCC connected to I/O Expansion Shield (A0-V)
• GND connected to I/O Expansion Shield (A0-G)

Micro SD Card Module

• cs connected to I/O Expansion Shield (D10)
• sck connected to I/O Expansion Shield (D13)
• mosi connected to I/O Expansion Shield (D11)
• miso connected to I/O Expansion Shield (D12)
• vcc connected to I/O Expansion Shield (5V)
• gnd connected to I/O Expansion Shield (GND)

Documented Code

Arduino Nano Code (sketch.ino)

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

Additional Documentation (documentation.txt)

No additional code documentation provided.

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This document provides an overview of the circuit components, their wiring, and the initial code structure for the Arduino Nano. Further development of the code is required to initialize and read data from the sensors, manage the data logging to the SD card, and handle any other functionalities intended for this circuit.