Getting started with Keypad module and Arduino Nano

In this tutorial, we will learn how to interface a keypad module with an Arduino Nano and display the pressed keys on the Serial Monitor. Keypads are a simple and effective way to add input functionality to your Arduino projects.

Components Needed

- Arduino Nano

- Keypad module (4x4 or 4x3)

- Jumper wires

- Breadboard (optional)

- USB cable to connect Arduino Nano to the computer

Step 1: Connect the Keypad to the Arduino Nano

1. Identify the Keypad Pins: Most keypads have a set of row and column pins. A 4x4 keypad typically has 8 pins (4 for rows and 4 for columns), while a 4x3 keypad has 7 pins (4 for rows and 3 for columns).

2. Connect the Keypad Pins to Arduino: Use jumper wires to connect the keypad pins to the Arduino Nano. Here's an example connection for a 4x4 keypad:

- Keypad Pin 1 (Row 1) to Arduino Digital Pin 2

- Keypad Pin 2 (Row 2) to Arduino Digital Pin 3

- Keypad Pin 3 (Row 3) to Arduino Digital Pin 4

- Keypad Pin 4 (Row 4) to Arduino Digital Pin 5

- Keypad Pin 5 (Column 1) to Arduino Digital Pin 6

- Keypad Pin 6 (Column 2) to Arduino Digital Pin 7

- Keypad Pin 7 (Column 3) to Arduino Digital Pin 8

- Keypad Pin 8 (Column 4) to Arduino Digital Pin 9

Step 2: Install the Keypad Library

1. Open the Arduino IDE:

2. Go to Library Manager: Navigate to `Sketch` -> `Include Library` -> `Manage Libraries`.

3. Search for Keypad Library: In the Library Manager, type "Keypad" in the search bar.

4. Install the Library: Find the "Keypad by Mark Stanley, Alexander Brevig" and click "Install".

Step 3: Write the Arduino Code

1. Open a New Sketch in Arduino IDE:

2. Include the Keypad Library: #include <Keypad.h>

Step 4: Upload and Test the Code

1. Connect the Arduino Nano to your Computer: Use the USB cable.

2. Select the Correct Board and Port: Go to `Tools` -> `Board` -> `Arduino Nano`, and then `Tools` -> `Port` to select the appropriate COM port.

3. Upload the Sketch: Click the upload button in the Arduino IDE.

4. Open the Serial Monitor: Navigate to `Tools` -> `Serial Monitor` and set the baud rate to 9600.

Step 5: Press Keys on the Keypad

With everything set up, press the keys on the keypad. You should see the corresponding key values displayed on the Serial Monitor.