#include <Ticker.h>

#define LED_ON_BOARD 2
#define YELLOW 22
#define RED 21
#define BUTTON 23
#define POT 34

Ticker blinker;

unsigned long buttonTime = 0;
unsigned long lastButtonTime = 0;
int potValue = 0;

ICACHE_RAM_ATTR void pressButton(){
  buttonTime = millis();
  if(buttonTime - lastButtonTime > 250){
    digitalWrite(RED, !digitalRead(RED));
    lastButtonTime = buttonTime;
  }
}

void blink(){
  digitalWrite(LED_ON_BOARD, !digitalRead(LED_ON_BOARD));
}

void setup() {
  pinMode(LED_ON_BOARD, OUTPUT);
  pinMode(RED, OUTPUT);
  pinMode(BUTTON, INPUT_PULLUP);
  blinker.attach(1, blink);
  attachInterrupt(digitalPinToInterrupt(BUTTON), pressButton, FALLING);
  digitalWrite(RED, LOW);
  Serial.begin(9600);
}

void loop() {
  potValue = analogRead(POT);
  potValue = map(potValue, 0, 1023, 0, 255);
  analogWrite(YELLOW, potValue);
}