Arduino Experiment: LCD Display Basics

Needed Components with eBay Links

• Arduino Uno
• 16x2 LCD Display
• 10kΩ Potentiometer
• 220Ω Resistor
• Breadboard
• Jumper Wires
• USB Cable

Understanding the LCD 16x2

The 16x2 LCD display has 16 columns and 2 rows, allowing it to display up to 32 characters at a time. It uses the HD44780 driver, which is widely supported by libraries available in the Arduino IDE. This display is perfect for showing text, numbers, and even custom characters.

Pin Configuration

The LCD has 16 pins. The most important ones to note for this experiment include:

• VSS: Ground
• VDD: 5V
• V0: Contrast (connected to potentiometer)
• RS: Register Select
• EN: Enable
• D4-D7: Data pins for 4-bit mode
• A: Backlight Anode
• K: Backlight Cathode

Wiring the Circuit

Connect the LCD to your Arduino as follows:

• VSS to GND
• VDD to 5V
• V0 to the middle pin of the potentiometer
• RS to digital pin 12
• EN to digital pin 11
• D4 to digital pin 5
• D5 to digital pin 4
• D6 to digital pin 3
• D7 to digital pin 2
• A to 5V through the 220Ω resistor
• K to GND

Arduino Code to Display Text on LCD

Before uploading the code, ensure the LiquidCrystal library is included (it comes pre-installed in the Arduino IDE).

// Include the library
#include 

// Initialize the library by passing the pin numbers
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
  // Set up the LCD's number of columns and rows
  lcd.begin(16, 2);
  // Print a message to the LCD
  lcd.print("Hello, World!");
}

void loop() {
  // Move the cursor to column 0, line 1
  lcd.setCursor(0, 1);
  // Print a message on the second line
  lcd.print("LCD Tutorial");
}
            

Upload & Test

1. Connect your Arduino to your computer using a USB cable.
2. Open the Arduino IDE and copy the code above into the editor.
3. Select your board and the correct port in the IDE.
4. Upload the code by clicking the upload button.
5. Once the upload is complete, the LCD should display "Hello, World!" on the first line and "LCD Tutorial" on the second line.

Code Breakdown

The code begins by including the LiquidCrystal library, which allows for easy interaction with the LCD. In the setup() function, we initialize the LCD and set its dimensions (16x2). Then, we print the message "Hello, World!" on the first line and move the cursor to the second line to display "LCD Tutorial". The loop() function is empty because we don't need to continuously update the display in this example.

Adjusting the Contrast

The potentiometer connected to the V0 pin allows you to adjust the contrast of the display. Rotate it until the characters are clearly visible.

Conclusion

This experiment demonstrates how to connect and control a 16x2 LCD display using Arduino. Once you master this, you can move on to more advanced experiments such as creating custom characters or building a simple user interface.