const int p_button = 23;
volatile int n_presses = 0;
volatile boolean pressed = false;

void IRAM_ATTR ISR_button() {
  n_presses++;
  pressed = true;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);

  pinMode(p_button, INPUT_PULLUP);
  attachInterrupt(p_button, ISR_button, FALLING);
}

void loop() {
  // put your main code here, to run repeatedly:
  if (pressed) {
    Serial.printf("Button pressed %d times\n", n_presses);
    pressed = false;
  }
}