#include <U8g2lib.h>
#include <Wire.h>
#include <ESP32Servo.h>
//U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, /* reset=*/ U8X8_PIN_NONE);
U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0);

Servo servo;
int value, lastValue, intensity; 

char myString[5];

void setup() {
  u8g2.begin();
  Serial.begin(115200);
  pinMode(13, INPUT);
  servo.attach(18, 500, 2400);
}

void loop() {
 
  value = analogRead(13);
  intensity = map(value, 0, 4098, 0, 180);
  
  if (value != lastValue)
    {
    lastValue = value;
    sprintf(myString, "%d", intensity);
    Serial.println(myString);
    servo.write(lastValue);
    }

  u8g2.clearBuffer();					// clear the internal memory
  u8g2.setFont(u8g2_font_ncenB08_tr);	// choose a suitable font
  u8g2.drawStr(15, 10, "TIME");	// write something to the internal memory
  u8g2.drawStr(15, 25, myString);
  u8g2.sendBuffer();					// transfer internal memory to the display
  delay(1000);
  
}