Circuit Documentation

Summary

This document provides a detailed overview of a circuit that integrates various components including an Arduino UNO, NodeMCU V3 ESP8266, a 12V battery, a 4x4 Membrane Matrix Keypad, an RFID-RC522 module, an I2C LCD 16x2 Screen, a 12V solenoid lock, and a 12V single-channel relay. The circuit is designed to perform tasks that likely involve user input through the keypad, RFID reading capabilities, display output on the LCD screen, and controlling access through the solenoid lock using the relay.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• Provides a range of digital and analog I/O pins
• Operates at 5V and has a 3.3V output pin

NodeMCU V3 ESP8266

• Wi-Fi enabled microcontroller module based on the ESP8266
• Offers multiple digital pins and a single analog input
• Can be used for IoT applications

Battery 12V

• Provides a 12V power source for components requiring higher voltage
• Typically used to power the solenoid lock and relay in this circuit

4X4 Membrane Matrix Keypad

• Input device with 16 buttons arranged in a 4x4 matrix
• Used for user input, such as entering a code for access control

RFID-RC522

• RFID reader/writer module operating at 13.56 MHz
• Used for contactless communication and identification

I2C LCD 16x2 Screen

• Alphanumeric liquid crystal display with 16 characters by 2 lines
• Utilizes the I2C communication protocol for displaying information

12V Solenoid Lock

• Electromechanical lock that operates at 12V
• Controlled by the relay to lock or unlock as needed

12V Single Channel Relay

• Electromechanical switch that can control high power devices
• Isolated by an optocoupler for safety and reliability

Wiring Details

Arduino UNO

• 3.3V connected to RFID-RC522 VCC (3.3V)
• 5V connected to I2C LCD Screen VCC (5V) and 12V Single Channel Relay VCC
• GND connected to NodeMCU V3 ESP8266 GND, RFID-RC522 GND, I2C LCD Screen GND, and 12V Single Channel Relay GND
• A0 connected to 4X4 Membrane Matrix Keypad C4
• A1 connected to 12V Single Channel Relay IN
• A4 connected to I2C LCD Screen SDA
• A5 connected to I2C LCD Screen SCL
• D2 to D13 connected to various pins of the 4X4 Membrane Matrix Keypad and RFID-RC522
• D0 and D1 connected to NodeMCU V3 ESP8266 RX and TX respectively

NodeMCU V3 ESP8266

• GND connected to Arduino UNO GND
• RX connected to Arduino UNO D0
• TX connected to Arduino UNO D1

Battery 12V

• + connected to 12V Single Channel Relay COM
• - connected to 12V Solenoid Lock GND

4X4 Membrane Matrix Keypad

• R1 to R4 and C1 to C4 connected to Arduino UNO D2 to D9 respectively

RFID-RC522

• VCC (3.3V) connected to Arduino UNO 3.3V
• GND connected to Arduino UNO GND
• SDA, MISO, MOSI, SCK connected to Arduino UNO D13, D12, D11, D10 respectively

I2C LCD 16x2 Screen

• SDA connected to Arduino UNO A4
• SCL connected to Arduino UNO A5
• VCC (5V) connected to Arduino UNO 5V
• GND connected to Arduino UNO GND

12V Solenoid Lock

• VCC connected to 12V Single Channel Relay NO
• GND connected to Battery 12V -

12V Single Channel Relay

• VCC connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• IN connected to Arduino UNO A1
• COM connected to Battery 12V +
• NO connected to 12V Solenoid Lock VCC

Documented Code

Arduino UNO Code (sketch.ino)

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

}

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

}

Note: The provided code for the Arduino UNO is a template with empty setup and loop functions. The actual functionality needs to be implemented based on the specific requirements of the circuit.

NodeMCU V3 ESP8266 Code

No code provided for the NodeMCU V3 ESP8266.

End of Documentation