SH1106 display: NTP clock with ESP8266 or ESP32

What do you need for this?

• Arduino IDE (free) — with the ESP8266 and ESP32 board manager URLs configured
• SH1106 display (1.3") — e.g. blue text version on AliExpress
• WiFiManager library — for a WiFi connection without a hard-coded password
• Adafruit_SH110X library (+ Adafruit GFX fonts) — driving the display
• An ESP8266 or ESP32 board — e.g. an inexpensive starter pack
• Solderless connecting wires

SH1106 display + ESP8266 | ESP32

This is a slightly larger display (1.3 inches), also easy to connect via the same pins as I2C. Compared to the SSD1306 code above, the library was changed and the time synchronization interval omitted. This code can also be used on both the ESP8266 and ESP32 without changes. Of course, SCL and SDA must go to D1 (GPIO5) and D2 (GPIO4) [ESP8266] or to 22 and 21 [ESP32] respectively.

Connections:

ESP32 ---> SDD1306 / SH1106
===========================
GND  --------> GND
3V3  --------> VCC
G21  --------> SDA
G22  --------> SCL
===========================
ESP8266 -> SDD1306 / SH1106
===========================
GND  --------> GND
3V3  --------> VCC
D2   --------> SDA
D1   --------> SCL

Sketch:

#include <WiFiManager.h>      // https://github.com/tzapu/WiFiManager/
#include <Adafruit_SH110X.h>  // https://github.com/adafruit/Adafruit_SH110X
#include <Fonts/FreeSansBold12pt7b.h>
#include <Fonts/FreeSansBold18pt7b.h>

WiFiManager myWiFi;  
Adafruit_SH1106G display = Adafruit_SH1106G(128, 64, &Wire, -1);  // GND -> GND, 3V3 -> VCC, esp32: G21 -> SDA, G22 -> SCL
struct tm tInfo;  // https://cplusplus.com/reference/ctime/tm/          esp8266: D1 -> SCL,  D2 -> SDA

void setup() {
  Serial.begin(115200);       // watch serial monitor in case of new WiFi-connection
  display.begin(0x3C, true);  // Address 0x3C default
  display.setTextColor(1);    // white = 1, black = 0
  display.setFont(&FreeSansBold12pt7b);
  myWiFi.autoConnect("SSD1306_ESP");  // connect ESP to new wifi via GSM or PC if new WiFi-connection
  configTzTime("CET-1CEST,M3.5.0,M10.5.0/3", "be.pool.ntp.org");
}

void loop() {
  getLocalTime(&tInfo);  // sntp sync at startup & every hour from then on (esp8266) - every 3 hours (esp32)
  display.clearDisplay();
  display.drawRect(0, 0, 128, 40, 1);
  display.setFont(&FreeSansBold18pt7b);
  display.setCursor(4, 31);
  display.printf("%02d:%02d", tInfo.tm_hour, tInfo.tm_min);
  display.setFont(&FreeSansBold12pt7b);
  display.printf(":%02d", tInfo.tm_sec);
  display.setCursor(4, 63);
  display.printf("%02d-%02d-%04d", tInfo.tm_mday, 1 + tInfo.tm_mon, 1900 + tInfo.tm_year);
  display.display();
}

More displays with the ESP8266 / ESP32

Curious about other displays? Check out the full overview, including TM1637, SSD1306, ST7735, ST7789, e-paper and integrated displays like the Lilygo T-Display and the Waveshare ESP32-S3.