A PROJECT SUMMARY
Hey folks, I hope everything is going well. Today, we’re going to showcase a fantastic project that uses an Arduino keypad and password to lock a door. In order to enter the passcode and gain access to the system, we are employing a keypad for this project. This project is suitable for usage in both homes and workplaces. This security system is excellent and robust.
COMPONENTS REQUIRED
- ARDUINO NANO
- I2C LCD DISPLAY MODULE
- L293D MOTOR DRIVER MODULE
- 12V DOOR LOCK ACTUATOR
- 4X4 KEYPAD
- DOT PCB BOARD
- MALE AND FEMALE BERG STRIP
- CONNECTING WIRES
- 10K RESISTOR
- 10K NETWORK RESISTOR
Link to Buy Products mentioned in the video – https://eagleelectronicsonline.com/in…
HARDWARE CONNECTIONS
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1.16×2 I2C LCD TO Arduino Nano Connection
GND-Connect to Nano GND
VCC-Connect to Nano 5V
SDA-Connect to Nano Pin No-A4
SCL-Connect to Nano Pin No-A5
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2.4×4 Keypad To Arduino Nano Connection
Keypad R1 connect to Nano Pin No-12
Keypad R2 connect to Nano Pin No-11
Keypad R3 connect to Nano Pin No-10
Keypad R4 connect to Nano Pin No-9
Keypad C1 connect to Nano Pin No-8
Keypad C2 connect to Nano Pin No-7
Keypad C3 connect to Nano Pin No-6
Keypad C4 connect to Nano Pin No-5
Note:
Nano Pin No-12 connect 10K Reistor to Gnd
Nano Pin No-11 connect 10K Reistor to Gnd
Nano Pin No-10 connect 10K Reistor to Gnd
Nano Pin No-9 connect 10K Reistor to Gnd
————————————————————–
3. Push Switch To Arduino Nano Connection
Switch One end connect to Nano Pin 3.3V
Switch another end connect to Nano pin No-A0
Note:
Nano Pin No-A0 connect 10K Reistor to Gnd
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4. L293D Motor Driver To Arduino Nano Connection
12V Pin Connect To Battery Positive
Gnd Pin Connect To Battery Negative
IN-1 Pin Connect To Nano Pin No-2
IN-2 Pin Connect To Nano Pin No-3
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5.L293D Motor Driver To Lock Connection
Connect Lock to the Motor-1 (Terminal Block)
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6.Battery To Arduino Nano Connection
Battery Positive Terminal Connect To Nano pin-VIN
Battery Negative Terminal Connect To Nano pin-GND
————————————————————–
CODE FOR I2C ADDRESS SCANNER
#include <Wire.h>
void setup()
{
Wire.begin();
Serial.begin(9600);
while (!Serial); // Leonardo: wait for serial monitor
Serial.println("I2C Scanner");
}
void loop()
{
byte error, address;
int nDevices;
Serial.println("Scanning...");
nDevices = 0;
for(address = 1; address < 127; address++ )
{
// The i2c_scanner uses the return value of
// the Write.endTransmisstion to see if
// a device did acknowledge to the address.
Wire.beginTransmission(address);
error = Wire.endTransmission();
if (error == 0)
{
Serial.print("I2C device found at address 0x");
if (address<16)
Serial.print("0");
Serial.print(address,HEX);
Serial.println(" !");
nDevices++;
}
else if (error==4)
{
Serial.print("Unknown error at address 0x");
if (address<16)
Serial.print("0");
Serial.println(address,HEX);
}
}
if (nDevices == 0)
Serial.println("No I2C devices found");
else
Serial.println("done");
delay(5000); // wait 5 seconds for next scan
}
CODE FOR DIGITAL LOCK
#include <Keypad.h>
#include <EEPROM.h>
#include <LiquidCrystal_I2C.h>
#define Solenoid 2 //Actually the Gate of the transistor that controls the solenoid
#define Solenoid1 3
#define O_Button A0 //Push Button
#define I2C_ADDR 0x27 //I2C adress, you should use the code to scan the adress first (0x27) here
const byte numRows= 4; //number of rows on the keypad
const byte numCols= 4; //number of columns on the keypad
char keymap[numRows][numCols]=
{
{'1', '2', '3', 'A'},
{'4', '5', '6', 'B'},
{'7', '8', '9', 'C'},
{'*', '0', '#', 'D'}
};
char keypressed; //Where the keys are stored it changes very often
char code[]= {'0','0','0','0'}; //The default code, you can change it or make it a 'n' digits one
char code_buff1[sizeof(code)]; //Where the new key is stored
char code_buff2[sizeof(code)]; //Where the new key is stored again so it's compared to the previous one
short a=0,i=0,s=0,j=0; //Variables used later
byte rowPins[numRows] = {12,11,10,9}; //Rows 0 to 3 //if you modify your pins you should modify this too
byte colPins[numCols]= {8,7,6,5}; //Columns 0 to 3
LiquidCrystal_I2C lcd(0x27,16,2);
Keypad myKeypad= Keypad(makeKeymap(keymap), rowPins, colPins, numRows, numCols);
void setup()
{
lcd.begin ();
//lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
lcd.noBacklight();
lcd.home ();
lcd.print("Press * to enter"); //What's written on the LCD you can change
pinMode(Solenoid,OUTPUT);
pinMode(Solenoid1,OUTPUT);
// pinMode(motor1,OUTPUT);
pinMode(O_Button,INPUT);
// digitalWrite(motor1 , LOW);
// for(i=0 ; i<sizeof(code);i++){ //When you upload the code the first time keep it commented
// EEPROM.get(i, code[i]); //Upload the code and change it to store it in the EEPROM
// } //Then uncomment this for loop and reupload the code (It's done only once)
}
void loop()
{
keypressed = myKeypad.getKey(); //Constantly waiting for a key to be pressed
if(keypressed == '*'){ // * to open the lock
lcd.clear();
lcd.backlight();
lcd.setCursor(0,0);
lcd.print("Enter code"); //Message to show
GetCode(); //Getting code function
if(a==sizeof(code)) //The GetCode function assign a value to a (it's correct when it has the size of the code array)
OpenDoor(); //Open lock function if code is correct
else{
lcd.clear();
lcd.print("Wrong"); //Message to print when the code is wrong
}
delay(2000);
lcd.clear();
lcd.print("Press * to enter");
lcd.noBacklight();//Return to standby mode it's the message do display when waiting
}
if(keypressed == '2'){ //To change the code it calls the changecode function
ChangeCode();
lcd.clear();
lcd.print("Press * to enter"); //When done it returns to standby mode
lcd.noBacklight();
}
int sensorValue = analogRead(O_Button);
// Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
float voltage = sensorValue * (5.0 / 1023.0);
if(voltage > 3)
{ //Opening by the push button
digitalWrite(Solenoid,HIGH);
delay(1000); //Opens for 3s you can change
digitalWrite(Solenoid,LOW);
delay(10000);
digitalWrite(Solenoid1,HIGH);
delay(1000); //Opens for 3s you can change
digitalWrite(Solenoid1,LOW);
}
}
void GetCode(){ //Getting code sequence
i=0; //All variables set to 0
a=0;
j=0;
while(keypressed != '#'){ //The user press A to confirm the code otherwise he can keep typing
keypressed = myKeypad.getKey();
if(keypressed != NO_KEY && keypressed != '#' ){ //If the char typed isn't A and neither "nothing"
lcd.setCursor(j,1); //This to write "*" on the LCD whenever a key is pressed it's position is controlled by j
lcd.print("*");
j++;
if(keypressed == code[i]&& i<sizeof(code)){ //if the char typed is correct a and i increments to verify the next caracter
a++; //Now I think maybe I should have use only a or i ... too lazy to test it -_-'
i++;
}
else
a--; //if the character typed is wrong a decrements and cannot equal the size of code []
}
}
keypressed = NO_KEY;
}
void ChangeCode(){ //Change code sequence
lcd.clear();
lcd.backlight();
lcd.print("Changing code");
delay(1000);
lcd.clear();
lcd.print("Enter old code");
GetCode(); //verify the old code first so you can change it
if(a==sizeof(code)){ //again verifying the a value
lcd.clear();
lcd.print("Changing code");
GetNewCode1(); //Get the new code
GetNewCode2(); //Get the new code again to confirm it
s=0;
for(i=0 ; i<sizeof(code) ; i++){ //Compare codes in array 1 and array 2 from two previous functions
if(code_buff1[i]==code_buff2[i])
s++; //again this how we verifiy, increment s whenever codes are matching
}
if(s==sizeof(code)){ //Correct is always the size of the array
for(i=0 ; i<sizeof(code) ; i++){
code[i]=code_buff2[i]; //the code array now receives the new code
EEPROM.put(i, code[i]); //And stores it in the EEPROM
}
lcd.clear();
lcd.print("Code Changed");
delay(2000);
}
else{ //In case the new codes aren't matching
lcd.clear();
lcd.print("Codes are not");
lcd.setCursor(0,1);
lcd.print("matching !!");
delay(2000);
}
}
else{ //In case the old code is wrong you can't change it
lcd.clear();
lcd.print("Wrong");
delay(2000);
}
}
void GetNewCode1(){
i=0;
j=0;
lcd.clear();
lcd.print("Enter new code"); //tell the user to enter the new code and press A
lcd.setCursor(0,1);
lcd.print("and press #");
delay(2000);
lcd.clear();
lcd.setCursor(0,1);
lcd.print("and press #"); //Press A keep showing while the top row print ***
while(keypressed != '#'){ //A to confirm and quits the loop
keypressed = myKeypad.getKey();
if(keypressed != NO_KEY && keypressed != '#' ){
lcd.setCursor(j,0);
lcd.print("*"); //On the new code you can show * as I did or change it to keypressed to show the keys
code_buff1[i]=keypressed; //Store caracters in the array
i++;
j++;
}
}
keypressed = NO_KEY;
}
void GetNewCode2(){ //This is exactly like the GetNewCode1 function but this time the code is stored in another array
i=0;
j=0;
lcd.clear();
lcd.print("Confirm code");
lcd.setCursor(0,1);
lcd.print("and press #");
delay(3000);
lcd.clear();
lcd.setCursor(0,1);
lcd.print("and press #");
while(keypressed != '#'){
keypressed = myKeypad.getKey();
if(keypressed != NO_KEY && keypressed != '#' ){
lcd.setCursor(j,0);
lcd.print("*");
code_buff2[i]=keypressed;
i++;
j++;
}
}
keypressed = NO_KEY;
}
void OpenDoor()
{ //Lock opening function open for 3s
lcd.clear();
lcd.print("Door Opened"); //With a message printed
digitalWrite(Solenoid,HIGH);
delay(1000); //Opens for 3s you can change
digitalWrite(Solenoid,LOW);
delay(10000);
lcd.clear();
lcd.print("Door Closed");
digitalWrite(Solenoid1,HIGH);
delay(1000); //Opens for 3s you can change
digitalWrite(Solenoid1,LOW);
}
