m5.update+attachInterrupt causes bootloop

[kamilbar99]

I'm creating gps +speed meter device and i want to use buttons to change things on display. When button is clicked device get into bootloop and only thing I can do is reset device. Is there any possibility that interrupts will work with buttons or should i measure speed without interrupts?
Here is my code:

#include <M5Core2.h>
#include <TinyGPS++.h>

#define PIN 21
float start, finished;
float elapsed;
float circMetric=2.093; // wheel circumference (in meters)
float circImperial; // using 1 kilometer = 0.621371192 miles
float speedk, speedm;    // holds calculated speed vales in metric and imperial

// A sample NMEA stream.
const char *gpsStream =
  "$GPRMC,045103.000,A,3014.1984,N,09749.2872,W,0.67,161.46,030913,,,A*7C\r\n";

// The TinyGPS++ object
TinyGPSPlus gps;
static void smartDelay(unsigned long ms)
{
  unsigned long start = millis();
  do 
  {
    while (Serial2.available() > 0)
      gps.encode(Serial2.read());
  } while (millis() - start < ms);
  M5.Lcd.clear();
}


void displayInfo()
{
  M5.Lcd.setCursor(0, 40, 4);
  M5.Lcd.print(F("Latitude:    ")); 
  if (gps.location.isValid())
  {
    M5.Lcd.print(gps.location.lat(), 6);
    
  }
  else
  {
    M5.Lcd.print(F("INVALID"));
  }
  
  M5.Lcd.println();
  M5.Lcd.print(F("Longitude:    ")); 
  if (gps.location.isValid())
  {
    M5.Lcd.print(gps.location.lng(), 6);   
  }
  else
  {
    M5.Lcd.print(F("INVALID"));
  }
  
  M5.Lcd.println();
  M5.Lcd.print(F("Altitude:    ")); 
  if (gps.altitude.isValid())
  {
    M5.Lcd.print(gps.altitude.meters());
  }
  else
  {
    M5.Lcd.print(F("INVALID"));
  }

  M5.Lcd.println();
  M5.Lcd.print(F("Speed sensor: "));

  M5.Lcd.print(int(speedk));


  M5.Lcd.println();
  M5.Lcd.print(F("Speed: "));
  if (gps.speed.isValid())
  {
M5.Lcd.print(gps.speed.kmph());
  }
  
  else
  {
    M5.Lcd.print(F("INVALID"));
  }

}

void speedCalc()
{
  //Function called by the interrupt

  if((millis()-start)>100) // 100 millisec debounce
    {
    //calculate elapsed
    elapsed=millis()-start;

    //reset start
    start=millis();
  
    //calculate speed in km/h
    speedk=(3600*circMetric)/elapsed; 

    }

}

void setup()
{
M5.begin(true,true,true,false);
Serial2.begin(9600, SERIAL_8N1, 13, 14);
attachInterrupt(digitalPinToInterrupt(PIN), speedCalc, FALLING);
start=millis();
}

void loop()
{
  M5.update();
  if(M5.BtnC.wasPressed())
  {
    M5.Lcd.print(F("Change"));
  }
smartDelay(1000);
displayInfo();

}