Circuit Documentation

Summary

This circuit is designed to integrate various components including an Arduino UNO, a 12V solenoid lock, a 16x2 I2C LCD, a DFPlayer MINI, an RFID-RC522 module, a 5V relay, a step-down buck converter, a speaker, and a 12V power supply. The circuit is intended to control a solenoid lock using an RFID reader, display information on an LCD, and play audio through a speaker.

Component List

Arduino UNO

• Description: A microcontroller board based on the ATmega328P.
• Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0

12V Solenoid Lock

• Description: An electromechanical lock that operates on 12V.
• Pins: VCC, GND

16x2 I2C LCD

• Description: A 16x2 character LCD with I2C interface.
• Pins: GND, VCC, SDA, SCL

12V Power Supply

• Description: A power supply providing 12V output.
• Pins: +, -

5V Relay

• Description: A relay module that operates on 5V.
• Pins: Normally Open, Common terminal, Normally Closed, In, GND, VCC

DFPlayer MINI

• Description: A small MP3 player module.
• Pins: VCC, BUSY, RX, USB -, TX, USB +, DAC_R, K2/ADC_KEY, DAC_L, K1/ADC_KEY, SPK1, IO 2, GND, SPK2, IO 1

Speaker

• Description: A speaker for audio output.
• Pins: +, -

Resistor

• Description: A resistor with a resistance of 1000 Ohms.
• Pins: pin1, pin2

RFID-RC522

• Description: An RFID reader module.
• Pins: VCC (3.3V), RST, GND, IRQ, MISO, MOSI, SCK, SDA

Step Down Buck Converter

• Description: A buck converter to step down voltage.
• Pins: IN +, IN - GND, OUT +, OUT - GND

Rocker Switch

• Description: A switch to control the power supply.
• Pins: 1, 2

Wiring Details

Arduino UNO

• 3.3V connected to RFID-RC522 VCC (3.3V)
• 5V connected to DFPlayer MINI VCC, 5V relay VCC, 16x2 I2C LCD VCC
• GND connected to 5V relay GND, Step down Buck converter OUT - GND, DFPlayer MINI GND, 16x2 I2C LCD GND, RFID-RC522 GND
• Vin connected to Step down Buck converter OUT +
• A4 connected to 16x2 I2C LCD SDA
• A5 connected to 16x2 I2C LCD SCL
• D13 connected to RFID-RC522 SCK
• D12 connected to RFID-RC522 MISO
• D11 connected to RFID-RC522 MOSI
• D10 connected to RFID-RC522 SDA
• D9 connected to RFID-RC522 RST
• D6 connected to 5V relay In
• D3 connected to Resistor pin1
• D2 connected to DFPlayer MINI TX

12V Solenoid Lock

• VCC connected to 5V relay Normally Open
• GND connected to 12V power supply -, Step down Buck converter IN - GND

16x2 I2C LCD

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

12V Power Supply

• + connected to Rocker Switch pin 1
• - connected to 12V solenoid lock GND, Step down Buck converter IN - GND

5V Relay

• VCC connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• In connected to Arduino UNO D6
• Normally Open connected to 12V solenoid lock VCC
• Common terminal connected to Rocker Switch pin 2, Step down Buck converter IN +

DFPlayer MINI

• VCC connected to Arduino UNO 5V
• GND connected to Arduino UNO GND
• TX connected to Arduino UNO D2
• RX connected to Resistor pin2
• SPK1 connected to Speaker +
• SPK2 connected to Speaker -

Speaker

• + connected to DFPlayer MINI SPK1
• - connected to DFPlayer MINI SPK2

Resistor

• pin1 connected to Arduino UNO D3
• pin2 connected to DFPlayer MINI RX

RFID-RC522

• VCC (3.3V) connected to Arduino UNO 3.3V
• GND connected to Arduino UNO GND
• SCK connected to Arduino UNO D13
• MISO connected to Arduino UNO D12
• MOSI connected to Arduino UNO D11
• SDA connected to Arduino UNO D10
• RST connected to Arduino UNO D9

Step Down Buck Converter

• IN + connected to 5V relay Common terminal, Rocker Switch pin 2
• IN - GND connected to 12V power supply -, 12V solenoid lock GND
• OUT + connected to Arduino UNO Vin
• OUT - GND connected to Arduino UNO GND, 5V relay GND

Rocker Switch

• pin 1 connected to 12V power supply +
• pin 2 connected to 5V relay Common terminal, Step down Buck converter IN +

Code Documentation

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:

}

documentation.txt