How to Use 128x64 OLED Display (I2C IIC SPI Serial): Examples, Pinouts, and Specs

The DollaTek 128x64 OLED Display (SSH1106) is a compact, high-resolution display module that utilizes organic light-emitting diodes (OLED) to produce bright and vivid images. With a resolution of 128x64 pixels, this display is ideal for applications requiring clear and detailed visual output. It supports both I2C and SPI communication protocols, making it compatible with a wide range of microcontrollers, including Arduino, Raspberry Pi, and ESP32.

• Wearable devices and smart gadgets
• IoT dashboards and data visualization
• Portable instruments and measurement tools
• Embedded systems requiring graphical interfaces
• Educational and prototyping projects

Below are the key technical details of the DollaTek 128x64 OLED Display:

The display module has a total of 4 pins for I2C communication and 7 pins for SPI communication. Below is the pinout for both modes:

1. Power the Display: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to ground.
2. Select Communication Protocol:
   • For I2C: Connect the SCL and SDA pins to the corresponding I2C pins on your microcontroller.
   • For SPI: Connect the SCL, SDA, RES, DC, and CS pins to the appropriate SPI pins on your microcontroller.
3. Install Required Libraries: For Arduino, install the Adafruit_GFX and Adafruit_SSD1306 libraries via the Arduino Library Manager.
4. Write Code: Use the example code below to initialize and display content on the OLED.

• Ensure the power supply voltage matches the display's operating range (3.3V to 5V).
• Use pull-up resistors (typically 4.7kΩ) on the I2C lines (SCL and SDA) if not already present.
• Avoid excessive current draw from the microcontroller by powering the display from an external power source if needed.
• Handle the display module carefully to avoid damaging the OLED screen.

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// Define the OLED display width and height
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

// Create an instance of the display object
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);

  // Initialize the OLED display
  if (!display.begin(SSD1306_I2C_ADDRESS, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Halt execution if initialization fails
  }

  // Clear the display buffer
  display.clearDisplay();

  // Display a welcome message
  display.setTextSize(1);      // Set text size to 1 (smallest)
  display.setTextColor(SSD1306_WHITE); // Set text color to white
  display.setCursor(0, 0);     // Set cursor to top-left corner
  display.println(F("Hello, OLED!")); // Print message
  display.display();           // Update the display with the buffer
}

void loop() {
  // Add your code here to update the display dynamically
}

1. Display Not Turning On:

   • Verify the power connections (VCC and GND).
   • Ensure the correct voltage (3.3V or 5V) is supplied to the display.

2. No Output on the Display:

   • Check the I2C or SPI connections and ensure they are correctly wired.
   • Confirm the I2C address (default is 0x3C) matches the one in your code.
   • Ensure the required libraries (Adafruit_GFX and Adafruit_SSD1306) are installed.

3. Flickering or Unstable Display:

   • Use shorter wires to reduce noise in the communication lines.
   • Add decoupling capacitors (e.g., 0.1µF) near the power pins.

4. Library Initialization Fails:

   • Double-check the wiring and ensure the correct pins are used.
   • Verify that the display driver IC is SSH1106 and not SSD1306. If using a different driver, modify the library accordingly.

Q: Can this display work with 3.3V microcontrollers like ESP32?
A: Yes, the display is compatible with both 3.3V and 5V systems.

Q: How do I switch between I2C and SPI modes?
A: The display module typically has solder jumpers on the back to select the communication mode. Refer to the module's datasheet for details.

Q: Can I use this display for animations?
A: Yes, the display supports fast refresh rates, making it suitable for simple animations and dynamic content.

Q: Is the display sunlight-readable?
A: The OLED display is bright but not optimized for direct sunlight readability. Use it in shaded or indoor environments for best results.