Circuit Documentation

Summary

This document provides a detailed overview of a circuit that includes a NodeMCU V3 ESP8266 microcontroller, an MQ6 gas sensor, a DHT22 temperature and humidity sensor, a Micro SD Card Module, a Piezo Buzzer, a Step Down Buck Converter, and a 2x 18650 battery pack. The circuit is designed to read environmental data, store it, and provide alerts through a buzzer.

Component List

1. NodeMCU V3 ESP8266

   • Description: A microcontroller with built-in Wi-Fi capabilities.
   • 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. MQ6

   • Description: A gas sensor used to detect the presence of gases.
   • Pins: VCC, GND, A0, DO

3. DHT22

   • Description: A temperature and humidity sensor.
   • Pins: +, Out, -

4. Micro SD Card Module

   • Description: A module used to interface with a micro SD card for data storage.
   • Pins: cs, sck, mosi, miso, vcc, gnd

5. Piezo Buzzer

   • Description: A buzzer used for audio alerts.
   • Pins: pin 1, pin 2

6. Step Down Buck Converter

   • Description: A power converter that steps down voltage.
   • Pins: IN +, IN - GND, OUT +, OUT - GND

7. 2x 18650

   • Description: A battery pack consisting of two 18650 batteries.
   • Pins: vcc, gnd

Wiring Details

NodeMCU V3 ESP8266

• A0: Connected to A0 of MQ6
• GND: Connected to GND of MQ6, Micro SD Card Module, DHT22, Piezo Buzzer (pin 1), and Step Down Buck Converter (OUT - GND)
• Vin: Connected to VCC of MQ6, Micro SD Card Module, DHT22, and Step Down Buck Converter (OUT +)
• D1: Connected to pin 2 of Piezo Buzzer
• D2: Connected to Out of DHT22
• D5: Connected to sck of Micro SD Card Module
• D6: Connected to miso of Micro SD Card Module
• D7: Connected to mosi of Micro SD Card Module
• D8: Connected to cs of Micro SD Card Module

MQ6

• A0: Connected to A0 of NodeMCU V3 ESP8266
• GND: Connected to GND of NodeMCU V3 ESP8266
• VCC: Connected to Vin of NodeMCU V3 ESP8266

DHT22

• +: Connected to Vin of NodeMCU V3 ESP8266
• Out: Connected to D2 of NodeMCU V3 ESP8266
• -: Connected to GND of NodeMCU V3 ESP8266

Micro SD Card Module

• cs: Connected to D8 of NodeMCU V3 ESP8266
• sck: Connected to D5 of NodeMCU V3 ESP8266
• mosi: Connected to D7 of NodeMCU V3 ESP8266
• miso: Connected to D6 of NodeMCU V3 ESP8266
• vcc: Connected to Vin of NodeMCU V3 ESP8266
• gnd: Connected to GND of NodeMCU V3 ESP8266

Piezo Buzzer

• pin 1: Connected to GND of NodeMCU V3 ESP8266
• pin 2: Connected to D1 of NodeMCU V3 ESP8266

Step Down Buck Converter

• IN +: Connected to vcc of 2x 18650
• IN - GND: Connected to gnd of 2x 18650
• OUT +: Connected to Vin of NodeMCU V3 ESP8266
• OUT - GND: Connected to GND of NodeMCU V3 ESP8266

2x 18650

• vcc: Connected to IN + of Step Down Buck Converter
• gnd: Connected to IN - GND of Step Down Buck Converter

Code

No code is provided for this circuit.