SSD1306 OLED 배선과 초기화

An OLED is a tiny self-lit screen. Each pixel glows on its own, so you get crisp text and sharp graphics with no backlight needed. 💡

Most small OLEDs are driven by the SSD1306 controller. It manages the pixels for you, so your code just says what to draw, not how to light each dot.

An I2C OLED needs only four pins: VCC, GND, SDA, and SCL. Two for power, two for data. That simple wiring is why these screens are so popular.

On an Arduino Uno, SDA connects to A4 and SCL to A5. These are the board's built-in I2C lines, shared by every I2C device you add.

Each I2C device answers to an address. Most SSD1306 OLEDs use 0x3C. You pass this number so the board knows which chip it is talking to.

You drive the screen with two helpers: Adafruit_SSD1306 for the hardware and Adafruit_GFX for drawing. Install both from the Library Manager.

Start your sketch by including the libraries and stating the screen size. A common panel is 128x64 pixels wide by tall.

Make a display object that represents the screen. You hand it the size so every later draw call knows the canvas bounds.

Inside setup, call display.begin() with the address 0x3C. This powers up the panel and prepares it to receive your drawings.

Drawing happens in memory first. Call clearDisplay() to wipe that buffer so old pixels do not linger behind your new content.

Nothing shows until you call display(). It sends the whole buffer to the OLED at once, so changes appear together with no flicker.

You set up the screen but it stays blank. What did you forget?

You wired four pins, included the Adafruit libraries, began the SSD1306 at 0x3C, and learned to clear then push the buffer. Your OLED is ready to draw.