Introduction: Password Protected Door Lock on Tnikercad

For this project, we will take input from a keypad, process that input as an angle position, and move a servo motor based on the 3-digit angle acquired.

I used a 4 x 4 keypad, but if you have a 3x4 keypad, it has a very similar hookup, so it could be easily adapted. Similarly, some Arduino kits come with a 4x4 push-button matrix which work in exactly the same way.

Step 1: Components You Need to Make Your Project:

Components you will be required are:

1. Arduino UNO or Nano

2. Keypad 4*4

3. Servo motor

4. Led's

5. Resistors(220 ohms)

Step 2: Keypad 4*4 Pinout :

Keypad is used as an input device to read the key pressed by the user and to process it.

4x4 keypad consists of 4 rows and 4 columns. Switches are placed between the rows and columns. A key press establishes a connection between the corresponding row and column, between which the switch is placed. For more information about keypad and how to use it, refer the topic 4x4 Keypad in the sensors and modules section.

Please download the keypad library zip file if you are working on Arduino IDE from the link given below:

Connections are as below :

R1 = 3

R2 = 4

R3 = 5

R4 = 6

C1 = 8

C2 = 9

C3 = 10

C4 = 11

Step 3: Attaching Servo Motor With Arduino:

Servo motors are great devices that can turn to a specified position.

Usually, they have a servo arm that can turn 180 degrees. Using the Arduino, we can tell a servo to go to a specified position and it will go there. As simple as that! Servo motors were first used in the Remote Control (RC) world, usually to control the steering of RC cars or the flaps on an RC plane. With time, they found their uses in robotics, automation, and of course, the Arduino world.

Download servo library from the link given below:

connections of servo motor:

1. Orange wire i.e the signal pin is connected to pin number 7

2. The red wire is connected with 5v

3. The black wire is connected to the ground

Step 4: Code:

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