How to Use 2.0 inch TFT LCD display: Examples, Pinouts, and Specs

The 2.0 inch TFT LCD Display (Manufacturer: 1.21 GMT 020-02-8P, Part ID: ST7789) is a compact, high-resolution Thin-Film Transistor Liquid Crystal Display. It is designed to provide vibrant and colorful graphical output, making it ideal for applications requiring a small yet visually appealing display. This display is commonly used in embedded systems, IoT devices, handheld gadgets, and user interface panels.

• Graphical user interfaces for embedded systems
• IoT devices with visual feedback
• Portable medical devices
• Wearable electronics
• Small gaming consoles and multimedia players

Below are the key technical details of the 2.0 inch TFT LCD Display:

The display has an 8-pin interface. Below is the pinout and description:

To use the 2.0 inch TFT LCD Display, connect it to a microcontroller (e.g., Arduino UNO) via the SPI interface. Below is a typical wiring guide for connecting the display to an Arduino UNO:

Below is an example Arduino sketch to initialize and display graphics on the 2.0 inch TFT LCD using the Adafruit GFX and Adafruit ST7789 libraries:

#include <Adafruit_GFX.h>    // Core graphics library
#include <Adafruit_ST7789.h> // ST7789 driver library
#include <SPI.h>             // SPI library

// Define TFT pins
#define TFT_CS    10  // Chip Select pin
#define TFT_RST   8   // Reset pin
#define TFT_DC    9   // Data/Command pin

// Initialize the display object
Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);
  Serial.println("TFT Display Test");

  // Initialize the display
  tft.init(240, 320); // Initialize with 240x320 resolution
  tft.setRotation(1); // Set display orientation (1 = landscape)

  // Fill the screen with a solid color
  tft.fillScreen(ST77XX_BLACK);

  // Draw a rectangle with text
  tft.fillRect(50, 50, 140, 100, ST77XX_BLUE); // Draw blue rectangle
  tft.setTextColor(ST77XX_WHITE);             // Set text color to white
  tft.setTextSize(2);                         // Set text size
  tft.setCursor(60, 80);                      // Set text position
  tft.print("Hello!");                        // Print text
}

void loop() {
  // Add any animations or updates here
}

1. Voltage Levels: Ensure the display operates at 3.3V. If using a 5V microcontroller, use level shifters for the SPI lines.
2. Backlight Control: The backlight pin (BLK) can be connected to a PWM pin for brightness control or directly to 3.3V for full brightness.
3. Reset Pin: Always connect the RES pin to the microcontroller to ensure proper initialization during startup.
4. Library Compatibility: Use the Adafruit GFX and ST7789 libraries for easy integration and graphical functions.

1. Display Not Turning On:

   • Verify the power connections (VCC and GND).
   • Ensure the backlight pin (BLK) is connected to 3.3V or a PWM pin.

2. No Output or Incorrect Graphics:

   • Check the SPI connections (SCL, SDA, CS, DC).
   • Ensure the correct pins are defined in the code.
   • Verify that the Adafruit ST7789 library is installed and up to date.

3. Flickering or Unstable Display:

   • Ensure proper grounding between the display and the microcontroller.
   • Use shorter wires to reduce noise in SPI communication.

4. Backlight Not Working:

   • Confirm that the BLK pin is connected to 3.3V or a PWM pin.
   • Check for loose or broken connections.

Q: Can I use this display with a 5V microcontroller?
A: Yes, but you must use level shifters for the SPI lines (SCL, SDA, CS, DC, RES) to avoid damaging the display.

Q: What is the maximum frame rate supported?
A: The frame rate depends on the SPI clock speed. At 10 MHz SPI, the display can achieve smooth updates for most applications.

Q: Can I control the backlight brightness?
A: Yes, connect the BLK pin to a PWM-capable pin on your microcontroller to adjust brightness.

Q: Is this display compatible with Raspberry Pi?
A: Yes, the ST7789 driver is supported on Raspberry Pi. Use libraries like luma.lcd or Pillow for Python-based development.

By following this documentation, you can effectively integrate and troubleshoot the 2.0 inch TFT LCD Display in your projects.