Arduino Nano ESP32 - OLED

This tutorial provides instructions on how to use Arduino Nano ESP32 with OLED display. In detail, we will learn:

Hardware Preparation

1×Arduino Nano ESP32
1×USB Cable Type-C
1×SSD1306 I2C OLED Display 128x64
1×Jumper Wires
1×(Optional) 9V Power Adapter for Arduino Nano ESP32
1×(Recommended) Screw Terminal Adapter for Arduino Nano

Or you can buy the following sensor kit:

1×DIYables Sensor Kit 30 types, 69 units
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. We appreciate your support.

Overview of OLED Display

There are various kinds of OLED displays available. The most common-used OLED with Arduino Nano ESP32 is the SSD1306 I2C OLED 128x64 and 128x32 display.

OLED display

I2C OLED Display Pinout

  • GND pin: This should be connected to the ground of the Arduino Nano ESP32.
  • VCC pin: This is the power supply for the display which should be connected to the 3.3V or 5V.
  • SCL pin: This is a serial clock pin for I2C interface.
  • SDA pin: This is a serial data pin for I2C interface.
OLED pinout

※ NOTE THAT:

  • The pins of the OLED module can differ depending on the manufacturer and type. Please use the labels printed on the OLED module. Please take a close look!
  • This tutorial uses the OLED display that is driven by the SSD1306 I2C driver. We have tested it with the OLED display from DIYables and it works perfectly.

Wiring Diagram

  • Wiring diagram between Arduino Nano ESP32 and OLED 128x64
The wiring diagram between Arduino Nano ESP32 and OLED

This image is created using Fritzing. Click to enlarge image

  • Wiring diagram between Arduino Nano ESP32 and OLED 128x32
The wiring diagram between Arduino Nano ESP32 and OLED 128x32

This image is created using Fritzing. Click to enlarge image

The wiring table between Arduino Nano ESP32 and OLED display:

OLED Module Arduino Nano ESP32
Vin 3.3V
GND GND
SDA A4
SCL A5

How To Use OLED with Arduino Nano ESP32

Install SSD1306 OLED library

  • Click to the Libraries icon on the left bar of the Arduino IDE.
  • Search for “SSD1306” and locate the SSD1306 library from Adafruit.
  • Then, press the Install button to complete the installation.
Arduino Nano ESP32 OLED library
  • You will be prompted to install additional library dependencies.
  • To install all of them, click the Install All button.
Arduino Nano ESP32 Adafruit GFX sensor library

How to program for OLED

  • Include the library
#include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h>
  • Specify the dimensions of the OLED screen as 128 x 64.
#define OLED_WIDTH 128 // OLED display width, in pixels #define OLED_HEIGHT 64 // OLED display height, in pixels
  • Or specify the dimensions of an OLED screen that is 128x32.
#define OLED_WIDTH 128 // OLED display width, in pixels #define OLED_HEIGHT 32 // OLED display height, in pixels
  • Create an object of type SSD1306 OLED.
// declare an SSD1306 display object connected to I2C Adafruit_SSD1306 oled(OLED_WIDTH, OLED_HEIGHT, &Wire, -1);
  • In the setup() function, initiate the OLED display.
// initialize OLED display with address 0x3C for 128x64 if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println(F("SSD1306 allocation failed")); while (true); }
  • Then, you can display text, pictures, and draw a line...

Going forward, all codes will be for OLED 128x64. However, it is easy to modify them for OLED 128x32 by altering the screen size and adjusting the coordinates if necessary.

Arduino Nano ESP32 Code - Display Text on OLED

/* * This Arduino Nano ESP32 code was developed by newbiely.com * * This Arduino Nano ESP32 code is made available for public use without any restriction * * For comprehensive instructions and wiring diagrams, please visit: * https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-oled */ #include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h> #define OLED_WIDTH 128 // OLED width, in pixels #define OLED_HEIGHT 64 // OLED height, in pixels // create an OLED display object connected to I2C Adafruit_SSD1306 oled(OLED_WIDTH, OLED_HEIGHT, &Wire, -1); void setup() { Serial.begin(9600); // initialize OLED display with I2C address 0x3C if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println(F("failed to start SSD1306 OLED")); while (1); } delay(2000); // wait two seconds for initializing oled.clearDisplay(); // clear display oled.setTextSize(1); // set text size oled.setTextColor(WHITE); // set text color oled.setCursor(0, 10); // set position to display oled.println("esp32io.com"); // set text oled.display(); // display on OLED } void loop() { }

These are some functions that can be used to display text on the OLED:

  • oled.clearDisplay(): all pixels are off.
  • oled.drawPixel(x,y, color): plot a pixel in the x,y coordinates.
  • oled.setTextSize(n): set the font size, supports sizes from 1 to 8.
  • oled.setCursor(x,y): set the coordinates to start writing text.
  • oled.setTextColor(WHITE): set the text color.
  • oled.setTextColor(BLACK, WHITE): set the text color, background color.
  • oled.println(“message”): print the characters.
  • oled.println(number): print a number.
  • oled.println(number, HEX): print a number IN hex format.
  • oled.display(): call this method for the changes to make effect.
  • oled.startscrollright(start, stop): scroll text from left to right.
  • oled.startscrollleft(start, stop): scroll text from right to left.
  • oled.startscrolldiagright(start, stop): scroll text from left bottom corner to right upper corner.
  • oled.startscrolldiagleft(start, stop): scroll text from right bottom corner to left upper corner.
  • oled.stopscroll(): stop scrolling.

How to vertical and horizontal center align text/number on OLED

For information on how to align text and numbers vertically and horizontally on an OLED display, please refer to How to vertical/horizontal center on OLED.

Arduino Nano ESP32 Code - Drawing on OLED

/* * This Arduino Nano ESP32 code was developed by newbiely.com * * This Arduino Nano ESP32 code is made available for public use without any restriction * * For comprehensive instructions and wiring diagrams, please visit: * https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-oled */ #include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h> #define OLED_WIDTH 128 // OLED width, in pixels #define OLED_HEIGHT 64 // OLED height, in pixels // create an OLED display object connected to I2C Adafruit_SSD1306 oled(OLED_WIDTH, OLED_HEIGHT, &Wire, -1); void setup() { Serial.begin(9600); // initialize OLED display with I2C address 0x3C if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println(F("failed to start SSD1306 OLED")); while (1); } delay(2000); // wait two seconds for initializing oled.setCursor(0, 0); } void loop() { // draw a circle oled.clearDisplay(); oled.drawCircle(20, 35, 20, WHITE); oled.display(); delay(1000); // fill a circle oled.clearDisplay(); oled.fillCircle(20, 35, 20, WHITE); oled.display(); delay(1000); // draw a triangle oled.clearDisplay(); oled.drawTriangle(30, 15, 0, 60, 60, 60, WHITE); oled.display(); delay(1000); // fill a triangle oled.clearDisplay(); oled.fillTriangle(30, 15, 0, 60, 60, 60, WHITE); oled.display(); delay(1000); // draw a rectangle oled.clearDisplay(); oled.drawRect(0, 15, 60, 40, WHITE); oled.display(); delay(1000); // fill a rectangle oled.clearDisplay(); oled.fillRect(0, 15, 60, 40, WHITE); oled.display(); delay(1000); // draw a round rectangle oled.clearDisplay(); oled.drawRoundRect(0, 15, 60, 40, 8, WHITE); oled.display(); delay(1000); // fill a round rectangle oled.clearDisplay(); oled.fillRoundRect(0, 15, 60, 40, 8, WHITE); oled.display(); delay(1000); }

Arduino Nano ESP32 Code – Display Image

In order to display an image on OLED, we must first convert the image (in any format) to a bitmap array. This can be accomplished by using the online tool. The following image demonstrates how to convert an image to a bitmap array; I have used the Arduino Nano ESP32 icon as an example.

image to bitmap array

After conversion, take the array code and put it in place of the ArduinoIcon array in the code below.

/* * This Arduino Nano ESP32 code was developed by newbiely.com * * This Arduino Nano ESP32 code is made available for public use without any restriction * * For comprehensive instructions and wiring diagrams, please visit: * https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-oled */ #include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h> #define OLED_WIDTH 128 // OLED width, in pixels #define OLED_HEIGHT 64 // OLED height, in pixels // create an OLED display object connected to I2C Adafruit_SSD1306 oled(OLED_WIDTH, OLED_HEIGHT, &Wire, -1); // bitmap of arduino-icon image const unsigned char arduino_icon [] PROGMEM = { // 'arduino-icon', 128x64px 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, 0xfe, 0x00, 0x07, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x80, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xff, 0x80, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x07, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0xff, 0xff, 0x80, 0x00, 0x00, 0x01, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff, 0xfc, 0x00, 0x00, 0xff, 0xf0, 0x00, 0x00, 0xff, 0xfc, 0x00, 0x00, 0x3f, 0xfc, 0x00, 0x00, 0xff, 0xfc, 0x00, 0x03, 0xff, 0xfc, 0x00, 0x00, 0x7f, 0xf8, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xf8, 0x00, 0x0f, 0xff, 0xff, 0x00, 0x00, 0x3f, 0xf0, 0x00, 0x03, 0xff, 0xff, 0xc0, 0x00, 0x7f, 0xf0, 0x00, 0x1f, 0xff, 0xff, 0xc0, 0x00, 0x1f, 0xe0, 0x00, 0x0f, 0xff, 0xff, 0xe0, 0x00, 0x7f, 0xf0, 0x00, 0x7f, 0xff, 0xff, 0xe0, 0x00, 0x0f, 0xc0, 0x00, 0x1f, 0xff, 0xff, 0xf8, 0x00, 0x3f, 0xe0, 0x00, 0xff, 0xff, 0xff, 0xf8, 0x00, 0x07, 0x80, 0x00, 0x7f, 0xff, 0xff, 0xfc, 0x00, 0x1f, 0xe0, 0x00, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x03, 0x80, 0x00, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x1f, 0xc0, 0x01, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x03, 0x00, 0x01, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x1f, 0xc0, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0xc0, 0x03, 0xff, 0xff, 0xff, 0xff, 0x80, 0x00, 0x00, 0x07, 0xff, 0xf0, 0x7f, 0xff, 0x00, 0x0f, 0xc0, 0x07, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x0f, 0xff, 0xf0, 0x7f, 0xff, 0x80, 0x0f, 0x80, 0x07, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x1f, 0xff, 0xf0, 0x7f, 0xff, 0x80, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x3f, 0xff, 0xf0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x7f, 0xff, 0xf0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xfe, 0x00, 0x00, 0xff, 0xfc, 0x00, 0x00, 0xff, 0xfc, 0x00, 0x03, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xfe, 0x00, 0x00, 0xff, 0xfe, 0x00, 0x01, 0xff, 0xfc, 0x00, 0x01, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xfe, 0x00, 0x00, 0xff, 0xff, 0x00, 0x03, 0xff, 0xfc, 0x00, 0x01, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xfe, 0x00, 0x00, 0xff, 0xff, 0x00, 0x03, 0xff, 0xfc, 0x00, 0x01, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xfe, 0x00, 0x00, 0xff, 0xff, 0x00, 0x03, 0xff, 0xfc, 0x00, 0x01, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x01, 0xff, 0xff, 0xe0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0xff, 0xff, 0xf0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0xff, 0xff, 0xf0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x7f, 0xff, 0xf0, 0x7f, 0xff, 0xc0, 0x07, 0x80, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x3f, 0xff, 0xf0, 0x7f, 0xff, 0x80, 0x07, 0x80, 0x07, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x1f, 0xff, 0xf0, 0x7f, 0xff, 0x80, 0x07, 0xc0, 0x07, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xff, 0xff, 0x80, 0x0f, 0xc0, 0x03, 0xff, 0xff, 0xff, 0xff, 0x80, 0x00, 0x00, 0x07, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0xc0, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0xe0, 0x01, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x03, 0x00, 0x01, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x1f, 0xe0, 0x00, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x07, 0x80, 0x00, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x1f, 0xe0, 0x00, 0x7f, 0xff, 0xff, 0xf0, 0x00, 0x0f, 0xc0, 0x00, 0x3f, 0xff, 0xff, 0xf8, 0x00, 0x3f, 0xf0, 0x00, 0x3f, 0xff, 0xff, 0xe0, 0x00, 0x1f, 0xe0, 0x00, 0x1f, 0xff, 0xff, 0xf0, 0x00, 0x3f, 0xf8, 0x00, 0x1f, 0xff, 0xff, 0x80, 0x00, 0x3f, 0xe0, 0x00, 0x07, 0xff, 0xff, 0xe0, 0x00, 0x7f, 0xf8, 0x00, 0x0f, 0xff, 0xff, 0x00, 0x00, 0x7f, 0xf8, 0x00, 0x03, 0xff, 0xff, 0xc0, 0x00, 0x7f, 0xfc, 0x00, 0x03, 0xff, 0xf8, 0x00, 0x00, 0xff, 0xfc, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xfe, 0x00, 0x00, 0x7f, 0xe0, 0x00, 0x01, 0xff, 0xfe, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0x01, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x01, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xf0, 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x0f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x03, 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 }; void setup() { Serial.begin(9600); // initialize OLED display with I2C address 0x3C if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { Serial.println(F("failed to start SSD1306 OLED")); while (1); } delay(2000); // wait two seconds for initializing oled.setCursor(0, 0); } void loop() { oled.clearDisplay(); // display bitmap oled.drawBitmap(0, 0, arduino_icon, 128, 64, WHITE); oled.display(); delay(1000); // invert display oled.invertDisplay(1); delay(1000); }

※ NOTE THAT:

  • The size of the image should not be larger than the size of the screen.
  • If you wish to use the code for an OLED 128x32, you must resize the image and adjust the width and height parameters in the oled.drawBitmap(); function.

OLED Troubleshooting

Verify that the OLED is functioning properly by doing the following:

  • Ensure that your wiring is correct.
  • Confirm that your OLED utilizes the SSD1306 driver.
  • Utilize the I2C Address Scanner code on Arduino Nano ESP32 to check the I2C address of the OLED.
// I2C address scanner program #include <Wire.h> void setup() { Wire.begin(); Serial.begin(9600); Serial.println("I2C Scanner"); } void loop() { byte error, address; int nDevices; Serial.println("Scanning..."); nDevices = 0; for (address = 1; address < 127; address++ ) { Wire.beginTransmission(address); error = Wire.endTransmission(); if (error == 0) { Serial.print("I2C device found at address 0x"); if (address < 16) Serial.print("0"); Serial.print(address, HEX); Serial.println(" !"); nDevices++; } else if (error == 4) { Serial.print("Unknown error at address 0x"); if (address < 16) Serial.print("0"); Serial.println(address, HEX); } } if (nDevices == 0) Serial.println("No I2C devices found"); else Serial.println("done"); delay(5000); // wait 5 seconds for next scan }

The output displayed on the Serial Monitor looks like below:

COM6
Send
Scanning... I2C device found at address 0x3C ! done Scanning... I2C device found at address 0x3C ! done
Autoscroll Show timestamp
Clear output
9600 baud  
Newline