Oled module must be connected to controller module or with sensor module.

The example code above shows counter value on screen

#include <Arduino.h>
#include <ittiot.h>
#include <Ticker.h>
#include <ESP8266WiFi.h>
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
 
#define OLED_RESET 0  // GPIO0
 
Ticker timeTicker;
Adafruit_SSD1306 display(OLED_RESET);
 
// ITT splashs screen bitmap. Generator: http://javl.github.io/image2cpp/
static const unsigned char PROGMEM logo16_glcd_bmp[] =
{
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x07, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x07, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x07, 0x1f, 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x00, 0xc0, 0x00, 0x00,
	0x00, 0x07, 0x00, 0x00, 0x00, 0xc0, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x00, 0xc0, 0x00, 0x00,
	0x00, 0x07, 0x1f, 0xe3, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x07, 0x1f, 0xe3, 0xff, 0xc0, 0x00, 0x00,
	0x00, 0x07, 0x10, 0xe2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0x10, 0xe2, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x07, 0x10, 0xe2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0x10, 0xe3, 0xff, 0xff, 0xf8, 0x00,
	0x00, 0x07, 0x10, 0xe0, 0x00, 0x00, 0x18, 0x00, 0x00, 0x07, 0x10, 0xe0, 0x00, 0x00, 0x18, 0x00,
	0x00, 0x07, 0x10, 0xe0, 0x00, 0x00, 0x18, 0x00, 0x00, 0x07, 0x10, 0xe3, 0xfc, 0xff, 0xf8, 0x00,
	0x00, 0x07, 0x10, 0xe3, 0xfc, 0xff, 0xf8, 0x00, 0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x07, 0x10, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x07, 0xf0, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0xe2, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfe, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x80, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
 
#if (SSD1306_LCDHEIGHT != 48)
#error("Height incorrect, please fix Adafruit_SSD1306.h!");
#endif
 
bool isBootModeNormal;
bool sendDataFlag;
 
int i = 0;
 
// Ticker library callback, which will occur 0.5 second interval.
void sendData()
{
  sendDataFlag=true;
}
 
// Function started after the connection to the server is established.
void iot_connected()
{
  Serial.println("MQTT connected callback");
  iot.log("IoT OLED screen example!");
  isBootModeNormal = true;
}
 
void setup()
{
  Serial.begin(115200);
  Serial.println("Booting");
 
  // initialize with the I2C addr 0x3C (for the 64x48)
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
 
  // Since the buffer is intialized with an Adafruit splashscreen
  // internally, we should clear it
  display.clearDisplay();
 
  // Load ITT splash screen into buffer
  display.drawBitmap(0, 0,  logo16_glcd_bmp, 64, 48, 1);
  // Show image buffer on the display
  display.display();
 
  // Display splashscreen two second
  delay(2000);
 
  // print IoT json config to serial
  iot.printConfig();
 
  // Initialize IoT library
  iot.setup();
 
  // Initialize Ticker interval and callback
  timeTicker.attach(0.5, sendData);
}
 
void loop()
{
  // IoT behind the plan work, it should be periodically called
  iot.handle();
 
  // Increase counter value
  i++;
 
  // Display counter value and boot mode on the OLED screen
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0,0);
  display.println("Counter: ");
  display.println(i);
 
  display.setCursor(0,30);
 
  if(isBootModeNormal)
  {
    display.println("Mode: NORM");
  }
  else
  {
    display.println("Mode: BOOT");
  }
 
  display.display();
 
  // Send counter value to the server
  if(WiFi.isConnected() && isBootModeNormal)
  {
    if(sendDataFlag)
    {
      sendDataFlag = false;
      String msg = String(i);
      iot.publishMsg("count", msg.c_str());
      Serial.println(msg);
    }
  }
}