ESP8266 - SSD1309 OLED Display
This tutorial instructs you how to use ESP8266 with a 2.42 inch (2.4") SSD1309 I2C OLED display (128×64 resolution). In detail, we will learn:
- How to connect a 2.42 inch SSD1309 OLED display to ESP8266.
- How to program ESP8266 to display text on the SSD1309 OLED.
- How to program ESP8266 to draw shapes on the SSD1309 OLED.
- How to enable hardware scrolling on the SSD1309 OLED with ESP8266.
- How to program ESP8266 to display bitmap images on the SSD1309 OLED.
- How to adjust brightness/contrast of the SSD1309 OLED.
- How to use external fonts with the SSD1309 OLED display.
Hardware Preparation
Or you can buy the following kits:
| 1 | × | DIYables Sensor Kit (30 sensors/displays) | |
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
Disclosure: Some of the links provided in this section are Amazon affiliate links. We may receive a commission for any purchases made through these links at no additional cost to you.
Additionally, some of these links are for products from our own brand, DIYables .
Additionally, some of these links are for products from our own brand, DIYables .
Overview of SSD1309 OLED Display
The SSD1309 is a monochrome OLED display driver chip. The 2.42 inch version provides a 128×64 pixel resolution. It communicates via I2C protocol, requiring only two pins (SDA and SCL) plus power connections. This makes it ideal for ESP8266 projects with limited pin availability.
Key features of the SSD1309 OLED:
- Display Size: 2.42 inches (diagonal)
- Resolution: 128×64 pixels
- Communication: I2C (2-wire interface)
- Default I2C Address: 0x3C
- Operating Voltage: 3.3V or 5V compatible (ESP8266 uses 3.3V)
- Built-in hardware scrolling support
- Adjustable contrast/brightness
- Low power consumption
SSD1309 OLED Display Pinout
The 2.42 inch SSD1309 I2C OLED module typically has 4 pins:
- GND: Ground pin - connect to ESP8266 GND
- VCC: Power supply pin - connect to ESP8266 3.3V
- SDA: I2C data line - connect to ESP8266 D2 (GPIO4)
- SCL: I2C clock line - connect to ESP8266 D1 (GPIO5)
※ NOTE THAT:
- The pins of an OLED module can differ across manufacturers and module types. It is essential to always refer to the labels printed on the OLED module. Pay attention!
- This tutorial uses the OLED display that has the SSD1309 I2C driver. We have tested it with the OLED display from DIYables and it works perfectly.
Wiring Diagram
Connect the 2.42 inch SSD1309 OLED display to ESP8266 following this wiring:
This image is created using Fritzing. Click to enlarge image
See more in ESP8266's pinout and how to supply power to the ESP8266 and other components.
| SSD1309 OLED | ESP8266 |
|---|---|
| VCC | 3.3V |
| GND | GND |
| SDA | D2 (GPIO4) |
| SCL | D1 (GPIO5) |
How To Use SSD1309 OLED with ESP8266
Install DIYables_OLED_SSD1309 Library
- Click on the Libraries icon on the left navigation bar of Arduino IDE.
- Type DIYables_OLED_SSD1309 in the search box and look for the library by DIYables.
- Click the Install button to add the library.
The DIYables_OLED_SSD1309 library depends on the Adafruit_GFX library. If Adafruit_GFX is not already installed, the Arduino IDE will automatically prompt you to install it when you install DIYables_OLED_SSD1309.
ESP8266 Code - Display "Hello World" on SSD1309 OLED
The below code shows how to display text on the 2.42 inch SSD1309 OLED display:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Hello World
* Prints text in two sizes on the 2.42 inch 128x64 I2C OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
display.setTextSize(1); // 6x8 pixels per character
display.setTextColor(SSD1309_PIXEL_ON); // turn pixels on
display.setCursor(0, 0);
display.println(F("Hello, World!"));
display.println();
display.setTextSize(2); // 12x16 pixels per character
display.println(F("DIYables"));
display.setTextSize(1);
display.println();
display.println(F("SSD1309 OLED 128x64"));
display.display(); // push buffer to screen
}
void loop() { }
Explanation
- Include necessary libraries and define constants
- Create display object with I2C address 0x3C
- Initialize display in setup()
- Set text size, color, and cursor position
- Print text to display buffer using print() and println()
- Call display.display() to push buffer content to the screen
※ NOTE THAT:
The F() macro stores strings in flash memory instead of RAM. This saves valuable RAM on ESP8266.
ESP8266 Code - Display Text with Various Formats
This code demonstrates text display with different sizes and number formatting:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Display Text
* Displays text in various sizes and formats on the 2.42" SSD1309 OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
// Various text sizes
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(0, 0);
display.println(F("Size 1 - DIYables"));
display.setTextSize(2);
display.println(F("Size 2"));
display.setTextSize(3);
display.println(F("Sz3"));
display.display();
delay(3000);
// Number formatting
display.clearDisplay();
display.setTextSize(1);
display.setCursor(0, 0);
int value = 42;
float pi = 3.14159;
display.print(F("Integer: "));
display.println(value);
display.print(F("Float: "));
display.println(pi, 2); // 2 decimal places
display.print(F("Hex: 0x"));
display.println(value, HEX);
display.print(F("Binary: 0b"));
display.println(value, BIN);
display.display();
}
void loop() { }
ESP8266 Code - Draw Shapes on SSD1309 OLED
The below code shows how to draw pixels, lines, rectangles, circles, and triangles:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Draw Shapes
* Demonstrates drawing pixels, lines, rectangles, circles, and triangles on the 2.42" OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
display.display();
}
void loop() {
// Draw pixels
display.clearDisplay();
for (int i = 0; i < 20; i++) {
display.drawPixel(random(SCREEN_WIDTH), random(SCREEN_HEIGHT), SSD1309_PIXEL_ON);
}
display.display();
delay(2000);
// Draw lines
display.clearDisplay();
for (int y = 0; y < SCREEN_HEIGHT; y += 8) {
display.drawLine(0, 0, SCREEN_WIDTH - 1, y, SSD1309_PIXEL_ON);
}
display.display();
delay(2000);
// Draw rectangles
display.clearDisplay();
display.drawRect(10, 10, 40, 30, SSD1309_PIXEL_ON); // outline
display.fillRect(60, 10, 40, 30, SSD1309_PIXEL_ON); // filled
display.drawRoundRect(10, 45, 40, 15, 5, SSD1309_PIXEL_ON); // rounded corners
display.display();
delay(2000);
// Draw circles
display.clearDisplay();
display.drawCircle(32, 32, 20, SSD1309_PIXEL_ON); // outline
display.fillCircle(96, 32, 20, SSD1309_PIXEL_ON); // filled
display.display();
delay(2000);
// Draw triangles
display.clearDisplay();
display.drawTriangle(20, 10, 10, 50, 30, 50, SSD1309_PIXEL_ON); // outline
display.fillTriangle(90, 10, 70, 50, 110, 50, SSD1309_PIXEL_ON); // filled
display.display();
delay(2000);
}
Available drawing functions:
- drawPixel(x, y, color) - Draw a single pixel
- drawLine(x0, y0, x1, y1, color) - Draw a line
- drawRect(x, y, w, h, color) - Draw rectangle outline
- fillRect(x, y, w, h, color) - Draw filled rectangle
- drawRoundRect(x, y, w, h, radius, color) - Draw rounded rectangle
- drawCircle(x, y, radius, color) - Draw circle outline
- fillCircle(x, y, radius, color) - Draw filled circle
- drawTriangle(x0, y0, x1, y1, x2, y2, color) - Draw triangle outline
- fillTriangle(x0, y0, x1, y1, x2, y2, color) - Draw filled triangle
ESP8266 Code - Hardware Scrolling on SSD1309 OLED
The SSD1309 supports hardware-based scrolling. This code demonstrates all four scroll directions:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Scroll Text
* Demonstrates all four hardware scroll directions on the 2.42" OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
display.setTextSize(2);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(10, 24);
display.println(F("DIYables"));
display.display();
delay(2000);
}
void loop() {
// Scroll right across all pages
display.startscrollright(0x00, 0x07);
delay(3000);
display.stopscroll();
delay(500);
// Scroll left
display.startscrollleft(0x00, 0x07);
delay(3000);
display.stopscroll();
delay(500);
// Diagonal scroll right
display.startscrolldiagright(0x00, 0x07);
delay(3000);
display.stopscroll();
delay(500);
// Diagonal scroll left
display.startscrolldiagleft(0x00, 0x07);
delay(3000);
display.stopscroll();
delay(500);
}
Scrolling functions:
- startscrollright(start, stop) - Scroll right
- startscrollleft(start, stop) - Scroll left
- startscrolldiagright(start, stop) - Diagonal scroll right
- startscrolldiagleft(start, stop) - Diagonal scroll left
- stopscroll() - Stop scrolling
The start and stop parameters define the page range (0x00 to 0x07 for full screen).
ESP8266 Code - Display Bitmap Image on SSD1309 OLED
This code shows how to display bitmap images stored in program memory:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Display Bitmap Image
* Shows a 16x16 heart icon and 128x64 DIYables logo on the 2.42" OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
// 16x16 heart icon bitmap
const unsigned char heart_icon[] PROGMEM = {
0x00, 0x00, 0x0c, 0x30, 0x1e, 0x78, 0x3f, 0xfc, 0x7f, 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0x7f, 0xfe, 0x3f, 0xfc, 0x1f, 0xf8, 0x0f, 0xf0, 0x03, 0xc0, 0x00, 0x00
};
// 128x64 DIYables logo bitmap
const unsigned char diyables_logo[] PROGMEM = {
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff,
0xff, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff,
0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff,
0xff, 0xff, 0xfe, 0x00, 0x07, 0xff, 0xc1, 0xff, 0xe0, 0x7f, 0xf0, 0x1f, 0xfc, 0x03, 0x00, 0x7f,
0xff, 0xff, 0xfc, 0x00, 0x1f, 0xff, 0xf7, 0xff, 0xf9, 0xff, 0xfc, 0x7f, 0xff, 0x0f, 0x80, 0x3f,
0xff, 0xff, 0xf8, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xfe, 0xff, 0xff, 0x9f, 0xc0, 0x1f,
0xff, 0xff, 0xf8, 0x00, 0x7f, 0x80, 0xff, 0x00, 0x7f, 0xc0, 0x3f, 0xf0, 0x0f, 0xfc, 0x00, 0x1f,
0xff, 0xff, 0xf0, 0x00, 0xfe, 0x00, 0x7f, 0x00, 0x3f, 0x80, 0x1f, 0xe0, 0x07, 0xf8, 0x00, 0x0f,
0xff, 0xff, 0xe0, 0x01, 0xfc, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x0f,
0xff, 0xff, 0xe0, 0x03, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x07,
0xff, 0xff, 0xc0, 0x07, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x03,
0xff, 0xff, 0xc0, 0x0f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x03,
0xff, 0xff, 0x80, 0x0f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x01,
0xff, 0xff, 0x80, 0x1f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x01,
0xff, 0xff, 0x00, 0x3f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xff, 0x00, 0x3f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xfe, 0x00, 0x7f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xfe, 0x00, 0x7f, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xfc, 0x00, 0xff, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xfc, 0x00, 0xff, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xfc, 0x01, 0xff, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xf8, 0x01, 0xff, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xf8, 0x03, 0xff, 0xf8, 0x00, 0x3e, 0x00, 0x1f, 0x00, 0x0f, 0xc0, 0x03, 0xf0, 0x00, 0x00,
0xff, 0xf0, 0x03, 0xff, 0xfc, 0x00, 0x7e, 0x00, 0x1f, 0x80, 0x1f, 0xe0, 0x07, 0xf8, 0x00, 0x00,
0xff, 0xf0, 0x07, 0xff, 0x7f, 0x80, 0xff, 0x00, 0x7f, 0xc0, 0x3f, 0xf0, 0x0f, 0xfc, 0x00, 0x00,
0xff, 0xf0, 0x07, 0xfe, 0x3f, 0xff, 0xff, 0xff, 0xfd, 0xff, 0xfe, 0xff, 0xff, 0x9f, 0xc0, 0x00,
0xff, 0xe0, 0x0f, 0xfc, 0x1f, 0xff, 0xf7, 0xff, 0xf9, 0xff, 0xfc, 0x7f, 0xff, 0x0f, 0x80, 0x00,
0xff, 0xe0, 0x0f, 0xf8, 0x07, 0xff, 0xc1, 0xff, 0xe0, 0x7f, 0xf0, 0x1f, 0xfc, 0x03, 0x00, 0x00,
0xff, 0xe0, 0x1f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xc0, 0x1f, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xc0, 0x3f, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xc0, 0x3f, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0x80, 0x7f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0x80, 0x7f, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0x80, 0xfe, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0x00, 0xfc, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0x01, 0xf8, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0x01, 0xf0, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xfe, 0x03, 0xe0, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xfe, 0x07, 0xc0, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xfc, 0x0f, 0x80, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xf8, 0x1f, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xf0, 0x3e, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xe0, 0x7c, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xc0, 0xf8, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0x81, 0xf0, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0x03, 0xe0, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
};
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
display.display();
}
void loop() {
// Display small heart icon centered
display.clearDisplay();
display.drawBitmap((SCREEN_WIDTH - 16) / 2, (SCREEN_HEIGHT - 16) / 2, heart_icon, 16, 16, SSD1309_PIXEL_ON);
display.display();
delay(3000);
// Display full-screen DIYables logo
display.clearDisplay();
display.drawBitmap(0, 0, diyables_logo, SCREEN_WIDTH, SCREEN_HEIGHT, SSD1309_PIXEL_ON);
display.display();
delay(3000);
// Invert display
display.invertDisplay(true);
delay(2000);
display.invertDisplay(false);
delay(1000);
}
To display images:
- Convert your image to a monochrome bitmap array (use online tools or image2cpp)
- Store the array in PROGMEM to save RAM
- Use drawBitmap(x, y, bitmap, width, height, color) to display
ESP8266 Code - Adjust Brightness/Contrast
Control the brightness and contrast of the SSD1309 OLED display:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – Contrast & Dim
* Sweeps contrast from 0→255→0 then toggles dim mode on the 2.42" OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
// Draw a test pattern so the contrast changes are visible
display.clearDisplay();
display.fillRect(0, 0, 64, 32, SSD1309_PIXEL_ON);
display.fillRect(64, 32, 64, 32, SSD1309_PIXEL_ON);
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_INVERSE);
display.setCursor(16, 28);
display.println(F("Contrast Demo"));
display.display();
delay(2000);
}
void loop() {
// Ramp up
for (int c = 0; c <= 255; c += 5) {
display.setContrast((uint8_t)c);
delay(30);
}
delay(1000);
// Ramp down
for (int c = 255; c >= 0; c -= 5) {
display.setContrast((uint8_t)c);
delay(30);
}
delay(1000);
// Quick dim toggle
display.dim(true); // minimum brightness
delay(2000);
display.dim(false); // restore
delay(2000);
}
Brightness control functions:
- setContrast(value) - Set contrast level (0-255, higher = brighter)
- dim(true/false) - Quick toggle between dim and normal brightness
- invertDisplay(true/false) - Invert all pixels (black↔white)
ESP8266 Code - Use External Fonts
The Adafruit_GFX library includes FreeFont typefaces. This code demonstrates three different fonts:
/*
* This ESP8266 NodeMCU code was developed by newbiely.com
*
* This ESP8266 NodeMCU code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/esp8266/esp8266-ssd1309-oled-display
*/
/*
* DIYables OLED SSD1309 – External Fonts
* Cycles through three FreeFont typefaces on the 2.42" SSD1309 OLED with ESP8266.
*/
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <DIYables_OLED_SSD1309.h>
#include <Fonts/FreeSerif9pt7b.h>
#include <Fonts/FreeSansBold12pt7b.h>
#include <Fonts/FreeMono9pt7b.h>
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
DIYables_OLED_SSD1309 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
void setup() {
Serial.begin(115200);
if (!display.begin(SSD1309_SWITCHCAPVCC, SCREEN_ADDRESS)) {
Serial.println(F("SSD1309 allocation failed"));
for (;;);
}
display.clearDisplay();
display.display();
}
void loop() {
// ── Built-in 5×7 font ──
display.clearDisplay();
display.setFont(NULL);
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(0, 0);
display.println(F("Built-in 5x7 font"));
display.println();
display.setTextSize(2);
display.println(F("DIYables"));
display.display();
delay(3000);
// ── FreeSerif 9pt ──
display.clearDisplay();
display.setFont(&FreeSerif9pt7b);
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(0, 14); // Y = baseline
display.println(F("FreeSerif 9pt"));
display.setCursor(0, 38);
display.println(F("DIYables OLED"));
display.setCursor(0, 58);
display.println(F("Hello World!"));
display.display();
delay(3000);
// ── FreeSansBold 12pt ──
display.clearDisplay();
display.setFont(&FreeSansBold12pt7b);
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(0, 20);
display.println(F("SansBold"));
display.setCursor(0, 52);
display.println(F("DIYables"));
display.display();
delay(3000);
// ── FreeMono 9pt ──
display.clearDisplay();
display.setFont(&FreeMono9pt7b);
display.setTextSize(1);
display.setTextColor(SSD1309_PIXEL_ON);
display.setCursor(0, 14);
display.println(F("FreeMono 9pt"));
display.setCursor(0, 34);
display.println(F("0123456789"));
display.setCursor(0, 54);
display.println(F("!@#$%^&*()"));
display.display();
delay(3000);
}
※ NOTE THAT:
FreeFont files are large. ESP8266 has limited flash memory (typically 4MB). Use only the fonts you need, or consider using smaller font sizes if memory is constrained.
Font usage:
- Include font header: #include <Fonts/FreeSans9pt7b.h>
- Set font: display.setFont(&FreeSans9pt7b)
- Reset to default: display.setFont(NULL)
- When using external fonts, Y coordinate represents the baseline, not the top
Troubleshooting
If the OLED display is not working, try these steps:
Check I2C Address
The default I2C address is 0x3C, but some modules use 0x3D. Run this I2C scanner to find the correct address:
#include <Wire.h>
void setup() {
Serial.begin(115200);
Wire.begin();
Serial.println("I2C Scanner");
byte count = 0;
for (byte i = 1; i < 127; i++) {
Wire.beginTransmission(i);
if (Wire.endTransmission() == 0) {
Serial.print("Found I2C device at 0x");
if (i < 16) Serial.print("0");
Serial.println(i, HEX);
count++;
}
}
Serial.print("Found ");
Serial.print(count);
Serial.println(" device(s)");
}
void loop() {}
If your display uses 0x3D, change SCREEN_ADDRESS to 0x3D in the code.
Check Wiring
Verify connections:
- VCC → 3.3V (not 5V for ESP8266)
- GND → GND
- SDA → D2 (GPIO4)
- SCL → D1 (GPIO5)
Check Power Supply
Make sure the ESP8266 is receiving adequate power through the USB cable or external power supply.