How to Use Adafruit Circuit Playground TFT Gizmo: Examples, Pinouts, and Specs

The Adafruit Circuit Playground TFT Gizmo is an add-on for the Circuit Playground Express and Bluefruit that adds a vibrant 240x240 pixel 1.54" TFT display with a 24-bit color depth. This display is perfect for adding graphics, color, and touch interface to your Circuit Playground projects. It's ideal for creating portable games, data visualization, or even as a tiny monitor for your microcontroller.

• Portable gaming devices
• Data visualization tools
• Interactive wearable electronics
• Educational projects for learning graphics programming
• User interfaces for projects requiring visual output

• Display Type: 1.54" TFT LCD
• Resolution: 240x240 pixels
• Color Depth: 24-bit (16 million colors)
• Interface: SPI
• Operating Voltage: 3.3V (powered via the Circuit Playground board)
• Touch Screen: Capacitive touch overlay

1. Mounting: Carefully align the TFT Gizmo over the Circuit Playground board, ensuring the connector pads touch the corresponding pads on the Circuit Playground.
2. Securing: Use the included screws and nuts to secure the TFT Gizmo to the Circuit Playground.
3. Programming: Use the Arduino IDE or CircuitPython to program the Circuit Playground board to interact with the TFT display.

• Power: Ensure that the Circuit Playground board is powered with a sufficient and stable power source to handle the additional current draw from the TFT display.
• Libraries: Install the necessary libraries for the TFT Gizmo, such as the Adafruit_GFX library for graphics and Adafruit_ST7789 for the display driver.
• Touch Sensitivity: When using the capacitive touch feature, calibrate the touch screen for accurate input.
• Updates: Keep the libraries and board firmware up to date to ensure compatibility and access to the latest features.

#include <Adafruit_GFX.h>    // Core graphics library
#include <Adafruit_ST7789.h> // Hardware-specific library for ST7789

// Define the pins for the TFT Gizmo
#define TFT_CS        A3
#define TFT_RST       A1
#define TFT_DC        A2

// Initialize the ST7789 display:
Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);

void setup() {
  tft.init(240, 240);           // Initialize the display with its resolution
  tft.fillScreen(ST77XX_BLACK); // Clear the screen to black
}

void loop() {
  // Display a simple line of text
  tft.setCursor(0, 0);          // Set the cursor to the top-left corner
  tft.setTextColor(ST77XX_WHITE);// Set the text color to white
  tft.setTextSize(1);            // Set the text size to 1
  tft.println("Hello, World!");  // Print the text to the screen
}

• Display Not Lighting Up: Ensure that the TFT Gizmo is properly mounted and secured to the Circuit Playground board. Check the power supply and connections.
• Garbled or No Display: Verify that the correct libraries are installed and that the pin definitions match the connections. Also, check for any updates to the libraries or firmware.
• Unresponsive Touch Screen: Calibrate the touch screen and ensure that the IRQ pin is correctly connected and configured in your code.

• Check Connections: Double-check that all connections are secure and that there are no shorts or open circuits.
• Library Issues: Reinstall the Adafruit_GFX and Adafruit_ST7789 libraries through the Library Manager in the Arduino IDE.
• Code Review: Look over your code to ensure there are no syntax or logical errors. Use serial debugging to help identify issues.

Q: Can I use the TFT Gizmo with other microcontrollers?

A: Yes, as long as the microcontroller supports SPI communication and operates at 3.3V logic levels.

Q: How do I update the firmware on my Circuit Playground board?

A: Firmware updates can be done through the Arduino IDE or the CircuitPython updater tool, depending on which programming language you are using.

Q: Is the touch screen resistive or capacitive?

A: The TFT Gizmo features a capacitive touch overlay, which provides a more responsive touch interface compared to resistive touch screens.