#include "OneButton.h"
#define ESP8266
#define PIN_INPUT 12
#define PIN_LED 13
// The 2. parameter activeLOW is true, because external wiring sets the button to LOW when pressed.
OneButton button(PIN_INPUT, true);
// current LED state, staring with LOW (0)
int ledState = LOW;
// save the millis when a press has started.
unsigned long pressStartTime;
#if defined(ESP8266)
ICACHE_RAM_ATTR void checkTicks() {
  button.tick(); // just call tick() to check the state.
}
#elif defined(ESP32)
void IRAM_ATTR checkTicks() {
  // include all buttons here to be checked
  button.tick(); }// just call tick() to check the state.
#endif
// this function will be called when the button was held down for 1 second or more.
void pressStart() {
  Serial.println("pressStart()");
 // pressStartTime = millis() - 500; // as set in setPressMs()
 digitalWrite(PIN_LED, 1);
} // pressStart()

// this function will be called when the button was released after a long hold.
void pressStop() {
  Serial.print("pressStop(");
  Serial.println(") detected.");
  digitalWrite(PIN_LED, 0);
} //pressStop()

// setup code here, to run once:
void setup() {
  Serial.begin(115200);
  pinMode(PIN_LED, OUTPUT);
  button.setPressMs(100); // that is the time when LongPressStart is called
  button.attachLongPressStart(pressStart);
  button.attachLongPressStop(pressStop);
} 

void loop() {
  // keep watching the push button, even when no interrupt happens:
  button.tick();
}