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System Description
Title: “Arduino Password Lock Design”
Functions:
-
Can set a password, unlock successfully
-
Five incorrect password inputs trigger an alarm (buzzer)
-
LCD display (1602)
-
RFID-RC522 radio frequency module (swipe card to unlock)
Modules Used:
-
Relay -
Infrared Remote Control (replaces matrix keyboard) -
RFID-RC522 radio frequency module -
LCD1602 (I2C)
Module Physical Diagram
Wiring Diagram
LCD1602
LCD1602 IIC — IIC
Infrared Receiver
Infrared Receiver — 5
Relay
Relay — 2
Buzzer
Buzzer — 3
RC522
SDA–10
SCK–13
MOSI–11
MISO–12
Other signal lines are idle.
Infrared Remote Control Signal
Source Code
/***************************
* Smart Door Lock Based on Arduino
* Author: Liu Zenglin
* Date: 2020.12.05
***************************
*/
#include <Wire.h>
#include <LiquidCrystal_I2C.h> //1602LCD Driver Reference I2C Library
#include <IRremote.h>
#include <SPI.h>
#include <MFRC522.h>
#define SS_PIN 10
#define RST_PIN 9
unsigned char i = 0, j = 0, m = 0, n = 0; // Loop variables
unsigned char code[6]; // Save password
unsigned char code_temp[6]; // Save temporary input password
int rf522_flag = 0; // Access card flag
int Setpassword_flag = 1; // Set password flag
int Inputpassword_flag = 1; // Input password flag
int door_flag = 0; // Door flag
// Pin definitions
const int buzzer = 3;
const int realy = 2;
LiquidCrystal_I2C lcd(0x27,16,2); // Configure LCD address and rows/columns
int RECV_PIN = 5;
IRrecv irrecv(RECV_PIN); // Define receive pin as pin 11.
decode_results results; // Declare a variable type unique to IRremote library (decode_results)
MFRC522 rfid(SS_PIN, RST_PIN); // Instantiate class
// Initialize array to store the read NUID
byte nuidPICC[4];
void setup() {
// put your setup code here, to run once:
// Pin initialization
pinMode(realy, OUTPUT);
digitalWrite(realy, HIGH);
pinMode(buzzer, OUTPUT);
digitalWrite(buzzer, HIGH);
SPI.begin(); // Initialize SPI bus
rfid.PCD_Init(); // Initialize MFRC522
//LCD1602
lcd.init(); // Initialize LCD
lcd.backlight(); // Set LCD backlight
lcd.setCursor(0,0); // Set display pointer
lcd.print(" Set Clded Lock "); // Output characters to LCD1602
lcd.setCursor(0,1); // Set display pointer
lcd.print("Password:"); // Output characters to LCD1602
//Infrared reception
irrecv.enableIRIn(); // Start receiving signals
Serial.begin(9600);
}
void loop() {
// put your main code here, to run repeatedly:
while (Setpassword_flag) // Set password
{
if (irrecv.decode(&results)) // Check if infrared remote signal is received
{
Serial.println(results.value, HEX); // Output hexadecimal received data command information
switch(results.value)// Compare through this loop
{
case 0xFF9867:
lcd.print("0");delay(500);code[i]=0;i++;break;
case 0XFFA25D:
lcd.print("1");delay(500);code[i]=1;i++;break;
case 0xFF629D:
lcd.print("2");delay(500);code[i]=2;i++;break;
case 0xFFE21D:
lcd.print("3");delay(500);code[i]=3;i++;break;
case 0xFF22DD:
lcd.print("4");delay(500);code[i]=4;i++;break;
case 0xFF02FD:
lcd.print("5");delay(500);code[i]=5;i++;break;
case 0xFFC23D:
lcd.print("6");delay(500);code[i]=6;i++;break;
case 0xFFE01F:
lcd.print("7");delay(500);code[i]=7;i++;break;
case 0xFFA857:
lcd.print("8");delay(500);code[i]=8;i++;break;
case 0xFF906F:
lcd.print("9");delay(500);code[i]=9;i++;break;
default:
break;
}
irrecv.resume(); // Receive next instruction
if (i == 6)
{
Setpassword_flag = 0; // Clear set password flag
Serial.print("Password set successfully\n");
for (j = 0; j < 6; j++)
{
Serial.print(code[j]);
}
Serial.println(" ");
digitalWrite(realy, LOW); // Password set successfully, unlock
delay(2000);
digitalWrite(realy, HIGH);
lcd.clear(); // Clear screen
lcd.setCursor(0,0); // Set display pointer
lcd.print("===Clded Lock==="); // Output characters to LCD1602
lcd.setCursor(0,1); // Set display pointer
lcd.print("Password:"); // Output characters to LCD1602
}
}
} // Password setting completed
while (Inputpassword_flag)
{
if (irrecv.decode(&results)) // Check if infrared remote signal is received
{
Serial.println(results.value, HEX); // Output hexadecimal received data command information
switch(results.value)// Compare through this loop
{
case 0xFF9867:
lcd.print("0");delay(500);code_temp[m]=0;m++;break;
case 0XFFA25D:
lcd.print("1");delay(500);code_temp[m]=1;m++;break;
case 0xFF629D:
lcd.print("2");delay(500);code_temp[m]=2;m++;break;
case 0xFFE21D:
lcd.print("3");delay(500);code_temp[m]=3;m++;break;
case 0xFF22DD:
lcd.print("4");delay(500);code_temp[m]=4;m++;break;
case 0xFF02FD:
lcd.print("5");delay(500);code_temp[m]=5;m++;break;
case 0xFFC23D:
lcd.print("6");delay(500);code_temp[m]=6;m++;break;
case 0xFFE01F:
lcd.print("7");delay(500);code_temp[m]=7;m++;break;
case 0xFFA857:
lcd.print("8");delay(500);code_temp[m]=8;m++;break;
case 0xFF906F:
lcd.print("9");delay(500);code_temp[m]=9;m++;break;
default:
break;
}
irrecv.resume(); // Receive next instruction
if (m == 6)
{
m = 0;
if ((code[0] == code_temp[0]) && (code[1] == code_temp[1]) && (code[2] == code_temp[2]) && (code[3] == code_temp[3]) && (code[4] == code_temp[4]) && (code[5] == code_temp[5]))
{
digitalWrite(realy, LOW); // Password set successfully, unlock
delay(2000);
digitalWrite(realy, HIGH);
}
else
{
n++;
}
lcd.clear(); // Clear screen
lcd.setCursor(0,0); // Set display pointer
lcd.print("===Clded Lock==="); // Output characters to LCD1602
lcd.setCursor(0,1); // Set display pointer
lcd.print("Password:"); // Output characters to LCD1602
}
while (n == 5)// Error five times buzzer alarm
{
// Buzzer alarm for 2s
digitalWrite(buzzer, LOW);
}
}
// Find card
if ( ! rfid.PICC_IsNewCardPresent())
{
rf522_flag = 1;
return;
}
if (rf522_flag == 1)
{
digitalWrite(realy, LOW);
delay(2000);
rf522_flag = 0;
digitalWrite(realy, HIGH);
}
}
}Demo Video
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