Circuit Documentation

Summary

The circuit in question is designed to integrate an Arduino UNO with an RFID-RC522 module, an ESP8266 ESP-12E WiFi module, a KY-019 Relay module, and a 12V solenoid lock, all powered by a 12V battery. The Arduino UNO serves as the central controller, interfacing with the RFID module for card reading capabilities and communicating with the ESP8266 for potential WiFi connectivity. The relay module is used to control the solenoid lock, which acts as an actuator in response to signals from the Arduino.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• Features digital I/O pins, analog input pins, and various power pins
• Provides SPI interface for communication with RFID module
• Serial communication with ESP8266 WiFi module

RFID-RC522

• RFID reader/writer module
• Operates at 13.56 MHz for NFC and RFID communication
• Interfaces with Arduino UNO via SPI

KY-019 Relay module 1 channel

• Single-channel relay module capable of controlling high power devices
• Controlled by Arduino UNO to switch the solenoid lock

12V solenoid lock

• Electromechanical lock powered by 12V
• Actuated by the relay module

ESP8266 ESP-12E WiFi Module

• WiFi module with capability for internet connectivity
• Communicates with Arduino UNO via serial (RX/TX)

Battery 12V

• Provides power to the solenoid lock and relay module

Wiring Details

Arduino UNO

• GND connected to common ground
• 3.3V supplies power to RFID-RC522 and ESP8266 modules
• 5V supplies power to KY-019 Relay module
• D13 connected to SCK of RFID-RC522
• D12 connected to MISO of RFID-RC522
• D11 connected to MOSI of RFID-RC522
• D10 connected to SDA of RFID-RC522
• D9 connected to RST of RFID-RC522
• D7 connected to S of KY-019 Relay module
• D1 (TX) connected to RXD of ESP8266
• D0 (RX) connected to TXD of ESP8266

RFID-RC522

• VCC (3.3V) connected to 3.3V of Arduino UNO
• RST connected to D9 of Arduino UNO
• GND connected to common ground
• IRQ not connected
• MISO connected to D12 of Arduino UNO
• MOSI connected to D11 of Arduino UNO
• SCK connected to D13 of Arduino UNO
• SDA connected to D10 of Arduino UNO

KY-019 Relay module 1 channel

• S connected to D7 of Arduino UNO
• 5V connected to 5V of Arduino UNO
• GND connected to common ground
• NC not connected
• COM connected to + of 12V battery
• NO connected to VCC of 12V solenoid lock

12V solenoid lock

• VCC connected to NO of KY-019 Relay module
• GND connected to - of 12V battery

ESP8266 ESP-12E WiFi Module

• GND connected to common ground
• VCC connected to 3.3V of Arduino UNO
• RXD connected to D1 (TX) of Arduino UNO
• TXD connected to D0 (RX) of Arduino UNO
• Remaining pins not connected or used for other functions not specified in this documentation

Battery 12V

• + connected to COM of KY-019 Relay module
• - connected to GND of 12V solenoid lock

Documented Code

Arduino UNO Code (sketch.ino)

#include <SPI.h>
#include <MFRC522.h>

#define SS_PIN 10

MFRC522 mfrc522(SS_PIN);

void setup() {
  SPI.begin();
  mfrc522.PCD_Init();
  Serial.begin(9600);
}

void loop() {
  if (mfrc522.PICC_IsNewCardPresent()) {
    if (mfrc522.PICC_ReadCardSerial()) {
      Serial.print("UID:");
      for (byte i = 0; i < mfrc522.uid.size; i++) {
        Serial.print(mfrc522.uid.uidByte[i], HEX);
      }
      Serial.println();
    }
  }
  delay(500);
}

This code initializes the RFID-RC522 module and continuously checks for new RFID cards. When a card is detected, it reads the UID and prints it to the serial monitor. The SS_PIN is defined as pin 10, which corresponds to the SDA pin on the RFID-RC522 module. The SPI library is used for communication between the Arduino UNO and the RFID module.