char led_red = 23;
char led_green = 18;
char led_yellow = 19;

char led_red_state = LOW;
char led_green_state = LOW;
char led_yellow_state = LOW;

long led_red_previous_millis = 0;
long led_green_previous_millis = 0;
long led_yellow_previous_millis = 0;
long ADC_previous_millis = 0;

int led_red_interval = 1000;
int led_green_interval = 1000;
int led_yellow_interval = 1000;
int ADC_interval = 1000;

void setup() {
  // put your setup code here, to run once:
  pinMode(led_red, OUTPUT);
  pinMode(led_green, OUTPUT);
  pinMode(led_yellow, OUTPUT);

  // Initialize serial communication
  Serial.begin(9600);
}

void loop() {
  long current_millis = millis();

  // Blinking red LED
  if (current_millis - led_red_previous_millis >= led_red_interval) {
    led_red_previous_millis = current_millis;

    // now reverse the led's state
    if (led_red_state == LOW)
      led_red_state = HIGH;
    else
      led_red_state = LOW;

    // control the led accordingly
    digitalWrite(led_red, led_red_state);
  }

  // Read ADC value
  if (current_millis - ADC_previous_millis >= ADC_interval) {
    ADC_previous_millis = current_millis;
    
    // Read ADC value
    int ADC_value = analogRead(A5);  // ensure A5 is the correct pin for ADC reading

    // Print ADC value to the Serial Monitor
    Serial.print("Analog Reading: ");
    Serial.println(ADC_value);
  }
}