LCD

Introduction

A 16×2 LCD is a character-based display capable of showing 16 characters per line on 2 lines, widely used in microcontroller projects for displaying text, numbers, or simple symbols.

When connected directly to a microcontroller, the LCD uses parallel communication, requiring multiple GPIO pins for control and data transfer.

Pin Configuration

LCD Pin	Function	Glyph-C3
RS	Register Select	GPIO 8
RW	GND	GND
EN	Enable	GPIO 9
D4	Data 4	GPIO 10
D5	Data 5	GPIO 2
D6	Data 6	GPIO 3
D7	Data 7	GPIO 4
VCC	Power	5V
VSS	GROUND	GND
V0	Contrast	Potentiometer wiper
LED+	Backlight +	5V
LED-	Backlight -	GND

Features

• Character Display: 16 columns × 2 rows.
• Controller: HD44780 or compatible.
• Parallel Communication: Direct pin-to-pin interface.
• Backlight: Built-in LED for better visibility.
• Custom Characters: Supports user-defined symbols via CGRAM.
• Contrast Control: Adjustable using a potentiometer.
• Voltage: Typically operates at 5V (some modules support 3.3V).
• Low Cost & Widely Available: Easy integration for embedded projects.

Typical Applications

• Embedded system displays – show status or messages.
• Sensor data monitoring – temperature, voltage, humidity.
• Industrial control panels – parameter display.
• IoT projects – display device or network status.
• Educational and prototyping projects – learn microcontroller interfacing.
• Home automation devices – show time, modes, or device status.
• DIY electronics – simple, low-cost display solution.

Step 1: Hardware Required

1. GLYPH
2. LCD Display
3. Potentiometer

Step 2: Circuit Diagram

Step 3: Code Setup

1. Open Arduino IDE.
2. Make sure to install the library
3. Copy and paste the following code into the Arduino IDE

#include <LiquidCrystal.h> //https://www.arduinolibraries.info/libraries/liquid-crystal-i2-c

// Initialize LCD with pin configuration: RS, EN, D4, D5, D6, D7
LiquidCrystal lcd(8, 9, 10, 2, 3, 4);

void setup() {
  // Initialize LCD with 16 columns and 2 rows
  lcd.begin(16, 2);
  
  // Print to LCD
  lcd.print("Hello ESP32!");
  lcd.setCursor(0, 1);
  lcd.print("LiquidCrystal");
}

void loop() {
  // Static display - nothing needed
  delay(1000);
}

Step 4: Upload the Code

1. Connect the Board

• Connect your GLYPH board to your computer

2. Select the Board and Port

Do the following settings in your Arduino IDE,

• Tools > Board > esp32 > Pcbcupid Glyph S3

warning

For the Pcbcupid Glyph S3 to appear under Tools > Board > esp32, the esp32 board version installed in the Arduino IDE should be greater or equal to 3.1.0.

• Tools > Port and select the port connected to your GLYPH.
• Tools > USB CDC on Boot > Enabled

warning

If USB CDC on BOOT not enabled, you won't be seeing any serial data on Arduino IDE.

3. Upload the Code

   • Click the upload button (➡️ icon) or use the shortcut CRTL + U in Arduino IDE to upload the code to the board.

Step 5: Observe Output on Serial Monitor