How to Use uLCD-144-G2 128: Examples, Pinouts, and Specs

The uLCD-144-G2 128 is a compact, low-power LCD display module designed for embedded systems and microcontroller applications. It features a 128x128 pixel resolution and supports multiple communication protocols, including UART (serial). This versatile display module is capable of rendering graphics, text, and basic animations, making it ideal for projects requiring a user interface. Its small size and low power consumption make it suitable for portable and battery-powered devices.

• User interfaces for embedded systems
• Portable devices and wearables
• Industrial control panels
• IoT devices with visual feedback
• Educational and hobbyist projects

Below are the key technical details of the uLCD-144-G2 128:

The uLCD-144-G2 128 has a 5-pin interface for communication and power. Below is the pinout:

To use the uLCD-144-G2 128, connect it to a microcontroller (e.g., Arduino UNO) as follows:

1. Connect the GND pin of the display to the GND pin of the microcontroller.
2. Connect the VCC pin of the display to the 5V pin of the microcontroller.
3. Connect the TX pin of the display to the RX pin of the microcontroller.
4. Connect the RX pin of the display to the TX pin of the microcontroller.
5. Optionally, connect the RESET pin to a GPIO pin on the microcontroller for manual resets.

Below is an example Arduino sketch to display text on the uLCD-144-G2 128:

#include <SoftwareSerial.h>

// Define the RX and TX pins for SoftwareSerial
SoftwareSerial lcdSerial(10, 11); // RX = pin 10, TX = pin 11

void setup() {
  lcdSerial.begin(9600); // Initialize serial communication with the display
  delay(1000); // Allow the display to initialize

  // Clear the screen and set background color
  lcdSerial.write(0xFF); // Command prefix
  lcdSerial.write(0xD7); // Clear screen command
  lcdSerial.write(0x00); // Background color (black)

  // Display text on the screen
  lcdSerial.write(0xFF); // Command prefix
  lcdSerial.write(0xE4); // Text command
  lcdSerial.write(0x01); // Font size (1 = small)
  lcdSerial.write(0x00); // X-coordinate (0)
  lcdSerial.write(0x00); // Y-coordinate (0)
  lcdSerial.print("Hello, World!"); // Text to display
}

void loop() {
  // No actions in the loop
}

• Ensure the display's operating voltage matches the microcontroller's logic level (5V for Arduino UNO).
• Use a level shifter if connecting to a 3.3V microcontroller.
• Avoid sending commands to the display too quickly; allow sufficient delays between commands.
• Refer to the manufacturer's command set documentation for advanced features like graphics and animations.

1. The display does not turn on:

   • Verify the power connections (VCC and GND).
   • Ensure the power supply provides sufficient voltage (4.0V to 5.5V).

2. No text or graphics appear on the screen:

   • Check the TX and RX connections between the microcontroller and the display.
   • Ensure the baud rate in the code matches the display's default baud rate (9600 bps).

3. The display resets unexpectedly:

   • Verify that the power supply is stable and not dropping below 4.0V.
   • Check for loose connections, especially on the RESET pin.

4. Text or graphics appear distorted:

   • Ensure the correct command sequence is being sent to the display.
   • Verify that the display's resolution (128x128) is being respected in the code.

• Use a logic analyzer or oscilloscope to monitor the UART communication.
• Test the display with a simple "Hello, World!" program to confirm basic functionality.
• Consult the manufacturer's datasheet for detailed command descriptions and examples.

By following this documentation, you can effectively integrate the uLCD-144-G2 128 into your projects and troubleshoot common issues.