Start stop with delay

Projects General Guidance
15 
//https://forum.arduino.cc/t/start-stop-with-delay/908129?


#define PUSHED         LOW
#define notPUSHED      HIGH

#define LEDon          HIGH
#define LEDoff         LOW

const byte potPin    = A0;

const byte ledPin    = 13; //Pin13---[220R]---[A->|-K]---GND
const byte buttonPin = 2;  //+5V---[50k internal PU resistor]---[Pin2]---[switch]---GND

byte ledState;
byte buttonStatenew;
byte buttonStateold  = notPUSHED;

unsigned int potVal;
unsigned int offTime;
unsigned int offTimeLocked;

unsigned long ledMillis;
unsigned long switchMillis;

//*********************************************************
void setup()
{
  Serial.begin(9600);

  pinMode (ledPin, OUTPUT);

  pinMode (buttonPin, INPUT_PULLUP);

} //END of setup()


//*********************************************************
void loop()
{
  //******************************
  //is it time to check the switches ?
  if (millis() - switchMillis >= 50)
  {
    //restart the TIMER
    switchMillis = millis();

    checkSwitches();
  }

  //******************************
  potVal = analogRead(potPin);

  offTime = map(potVal, 0, 1023, 1, 60); //set offtime to 1-60
  offTime = offTime * 1000;              //set offTime to seconds

  //******************************
  //when the LED is on, is it time to turn it OFF ?
  if (ledState == 1 && millis() - ledMillis >= offTimeLocked)
  {
    //disables TIMER checking
    ledState = 0;

    digitalWrite(ledPin, LEDoff); 
  }

  //******************************
  // Other non blocking code goes here
  //******************************

} //END of loop()


//*********************************************************
void checkSwitches()
{
  buttonStatenew = digitalRead(buttonPin);

  //**********************************
  //was there a change in switch state ?
  if (buttonStateold != buttonStatenew)
  {
    //update to the new state
    buttonStateold = buttonStatenew;

    //*************
    //when the LED is OFF, was the switch pushed ?
    if (ledState == LEDoff && buttonStatenew == PUSHED)
    {
      digitalWrite(ledPin, LEDon);

      //lock in the delay time
      offTimeLocked = offTime;
      Serial.print("Delay in ms will be = ");
      Serial.println(offTimeLocked);

      //enable TIMER checking
      ledState = LEDon;

      //restart the TIMER
      ledMillis = millis();
    }

    //*************
    //when the LED is ON, was the switch pushed ?
    else if (ledState == LEDon && buttonStatenew == PUSHED)
    {
      //cancels the LED timing and turns off the LED
      digitalWrite(ledPin, LEDoff);

      //disable TIMER checking
      ledState = LEDoff;
    }
  }

} //END of checkSwitches()