I2C LCD TFT with UART serial communication for MLX90615 IR thermometer freezing

I have one Ir temperature mlx90615 sensor like this:

Which is connected to one Arduino 2560 mega with one LCD TFT 2.4.

So my problem is when i insert some new object in the seen area of Ir sensor the output halt for some second delay and don't show new value via serial point or LCD output.

it characteristic table via datasheet of mlx90615 sensor is :


I have use this source code on library for mlx90615 into my codes by this site help:

The total codes are here:

#include "LiquidCrystal.h"
 
 #include <Adafruit_GFX.h>    // Adafruit's core graphics library
#include <Adafruit_TFTLCD.h> // Adafruit's hardware-specific library
#include <TouchScreen.h>     //Touchscreen library





#include <TimeLib.h>


bool backsensed = false;
bool resetsensed = false;


// most mcufriend shields use these pins and Portrait mode:
uint8_t YP = A1;  // must be an analog pin, use "An" notation!
uint8_t XM = A2;  // must be an analog pin, use "An" notation!
uint8_t YM = 7;   // can be a digital pin
uint8_t XP = 6;   // can be a digital pin


#define TS_MINX 100
#define TS_MINY 120
#define TS_MAXX 920
#define TS_MAXY 940
//Create the touchscreen object
TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);  //(data,data,data,data,sensitivity);

//Some of the tft pins
#define LCD_CS A3
#define LCD_CD A2
#define LCD_WR A1
#define LCD_RD A0
// Optional, used to reset the display
#define LCD_RESET A4


//Minimum and maximum pressure to sense the touch
#define MINPRESSURE 10
#define MAXPRESSURE 1000



 unsigned char Re_buf[11],counter=0;
 char sign=0;
float TO=0,TA=0;
void serialEvent();




   char i=0,sum=0;
 

   score=1;
    while(score==1){
    serialEvent();
    if(sign)
    {
       sign=0;
       for(i=0;i<8;i++)
        sum+=Re_buf[i];
       if(sum==Re_buf[i] )
       {
             TO=(float)(Re_buf[4]<<8|Re_buf[5])/100;
             if ((int)TO>=30){
              score=0;
             }
             tft.setTextSize(3);
             Serial.print("TO:");
             Serial.println(TO);
            tft.fillScreen(BLACK);
            tft.setCursor(10, 15);
            tft.print("Temprature :");
            tft.setCursor(10, 50);
            tft.print(TO);tft.setCursor(100, 30);tft.print("C");
             TA=(float)(Re_buf[6]<<8|Re_buf[7])/100;
             Serial.print("TA:");
             Serial.println(TA);
             delay(100);
     }
    }
  }

   delay(100);
   drawHome();
   return;
   
}




void setup()
{
  
  time_t t = now(); // store the current time in time variable t
  pinMode(A5, OUTPUT);pinMode(A6, OUTPUT); 
   
  tft.reset();
  tft.begin(tft.readID());
  tft.fillScreen(BLACK);
  tft.setRotation(1);

  currentpage = 0;

  tft.setTextSize(3);
  tft.setTextColor(WHITE);
  tft.setCursor(50, 140);
  tft.print("Loading...");

  tft.setTextColor(tft.color565(255, 255, 0));
  tft.setCursor(30, 70);
  tft.print("By:");

  tft.setCursor(30, 100);
  tft.print("NotesPoint.com GSH.IR");

  for (int i; i < 250; i++)
  {
    tft.fillRect(BAR_MINY - 10, BLUEBAR_MINX, i, 10, RED);
    delay(0.000000000000000000000000000000000000000000000000001);
  }

  tft.fillScreen(BLACK);
  score=14;
  if (EEPROM.read(1)==score){
  address=2;
  tft.setCursor(300, 100);
  tft.print("eeprom writed beffor");
  Heater_alarmSecond_end = EEPROM.read(address);
  Heater_alarmMinutes_end= EEPROM.read(address+1);
  Motor_alarmSecond_end = EEPROM.read(address+2);
  Motor_alarmMinutes_end = EEPROM.read(address+3);
  }
  else{
    tft.setCursor(300, 100);
  tft.print("new eeprom");
    address=1;
  EEPROM.write(address,14);
  EEPROM.write(address+1,10);
  EEPROM.write(address+2,4);
  EEPROM.write(address+3,10);
  EEPROM.write(address+4,0);
  address=1;
  
  Heater_alarmSecond_end = EEPROM.read(address);
  Heater_alarmMinutes_end= EEPROM.read(address+1);
  Motor_alarmSecond_end = EEPROM.read(address+2);
  Motor_alarmMinutes_end = EEPROM.read(address+3);
  }
  delay(100);
  drawHome();
  setTime(0, 0, 0, 20, 1, 2013); // hour, min, sec, day, month, year


Serial1.begin(115200);Serial.begin(115200);
  delay(1);

  Serial.write(0XA5);
  Serial1.write(0XA5);
  Serial1.write(0X15);
  Serial1.write(0XBA);
//buadrate 115200
  Serial1.write(0XA5);
  Serial1.write(0XAF);
  Serial1.write(0X54);
  



}
 
void loop() {

   char cc,i=0,sum=0;


  TSPoint p = ts.getPoint();     // Read touchscreen


  pinMode(XM, OUTPUT);
  pinMode(YP, OUTPUT);
  
for(i=0;i<8;i++){
  i=1;
 serialEvent();
  if(sign)
  {
     sign=0;
     for(i=0;i<8;i++)
      sum+=Re_buf[i];
     if(sum==Re_buf[i] )
     {
           TO=(float)(Re_buf[4]<<8|Re_buf[5])/100;
             
             tft.fillScreen(BLACK);
             tft.setTextColor(WHITE);
             tft.setTextSize(3);
             Serial.print("TO:");
             Serial.println(TO);
            
            tft.setCursor(10, 15);
            tft.print("Temprature :");
            tft.setCursor(10, 50);
            tft.print(TO);
            tft.setCursor(100, 30);tft.print("C");
             TA=(float)(Re_buf[6]<<8|Re_buf[7])/100;
             Serial.print("TA:");
             Serial.println(TA);
             delay(100);
   }
  }

 }

}
void serialEvent(){ 
  char i;
  Serial1.write(0XA5);
  Serial1.write(0X15);
  Serial1.write(0XBA);
  for (i=0;i<30;i++)
  {
    while (Serial1.available()) {
  
    Re_buf[counter]=(unsigned char)Serial1.read();
    if(counter==0&&Re_buf[0]!=0x5A) return;
    counter++;
    if(counter==9)
    {
       counter=0;i=600;
       sign=1;
    }
  }
  }
}

So has anybody this problem with this kind of sensors or other sensors?and why this happened?

Update:

Based of this site i have combined the blinky and mlx90615 uart sample code, and it's working without freeze, the code is shown below:

unsigned char Re_buf[11],counter=0;
unsigned char sign=0;
float TO=0,TA=0;
void setup() {
   pinMode(LED_BUILTIN, OUTPUT);
   Serial.begin(115200);
  delay(1);
  Serial.write(0XA5);
  Serial.write(0X45);
  Serial.write(0XEA);
}
 
void loop() {
  unsigned char i=0,sum=0;
 digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(50);                       // wait for a second
  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
  delay(50);  
  if(sign)
  {
     sign=0;
     for(i=0;i<8;i++)
      sum+=Re_buf[i];
     if(sum==Re_buf[i] )
     {
           TO=(float)(Re_buf[4]<<8|Re_buf[5])/100;
           Serial.print("TO:");
           Serial.println(TO);
           TA=(float)(Re_buf[6]<<8|Re_buf[7])/100;
           Serial.print("TA:");
           Serial.println(TA);
   }
  }
 
}
void serialEvent() {
  while (Serial.available()) {
    Re_buf[counter]=(unsigned char)Serial.read();
    if(counter==0&&Re_buf[0]!=0x5A) return;
    counter++;
    if(counter==9)
    {
       counter=0;
       sign=1;
    }
  }
}

I have read this queston: [Hardware Serial causes hang-up][6] and i think its related to I2C comunication with TFT LCD by this:

I think I found the solution. As you can see on the photo above, I
used unscreened wires in comparison with the Breadboard. I2C is
definitely very sensitive against EMP, which causes the bus freezes. I
now use screened wires and don´t use the Breadboard anymore. The issue
now occurs very rarely. Unfortunately I still don´t understand the
interdependency to the UART interface. I will now improve the
screening of my wireing. Hopefully, the breakdowns will totaly
diappear.

Or maby this be ther reason ; Arduino hangs when too much data is received.

Now it the end of week and i will go to holiday so i wil try newx two days by 16X2 Crystal LCD and printed board to check it happened again?

Until next two days i will appriciate any sugestion or help.

I have removed some part of codes and question becasue of 9000 characters restriction,So you could see the more complited question via arduino.stackexchange.com
Thanks a lot.