#include <TM1637.h>

const int CLK = 4;
const int DIO = 5;
TM1637 tm(CLK, DIO);

const int BUZZ = 13;

const int BUTT = 14;
const int SPOT = 18;

// Potentiometer is connected to GPIO 34 (Analog ADC1_CH6) 
const int potPin = 34;

// variable for storing the potentiometer value
int potValue = 0;
int oldValue = 0;
int buttstate = 0;
int warmup = 0;

void setup() {
  tm.init();
  tm.set(BRIGHT_TYPICAL);
  
  pinMode(BUZZ, OUTPUT);
  pinMode(BUTT, INPUT);
  pinMode(SPOT, OUTPUT);
  
  delay(3000);
  beep(100);
}

void loop() {

  tm.display(0, (potValue / 10) % 10);
  tm.display(1, potValue % 10);
  tm.display(2, 0);
  tm.display(3, 0); 
 
  oldValue = potValue;
  // Reading potentiometer value
  potValue = 1+analogRead(potPin)/410;
  delay(100);
  if(potValue != oldValue) beep(20);

// Read button and Spot
  buttstate = digitalRead(BUTT);
  if(buttstate == 1 ) {
     if(warmup == 0){
       beep(100);
       warmup = 1;
       digitalWrite(SPOT, HIGH);
       delay(potValue*100);
       digitalWrite(SPOT, LOW);
       beep(100);
       beep(100);
     }
  }
  delay(20);

  if(warmup == 1){
    delay(2000);
    warmup = 0;
    beep(1000);
  }
 
}

void beep(unsigned char delayms){
  analogWrite(BUZZ, 5);      // Almost any value can be used except 0 and 255
                           // experiment to get the best tone
  delay(delayms);          // wait for a delayms ms
  analogWrite(BUZZ, 0);       // 0 turns it off
  delay(delayms);          // wait for a delayms ms   
}