const int NOMINAL = 2048, ULIMIT1 = NOMINAL * 1.09, ULIMIT2 = NOMINAL * 1.10;
bool u1 = false, u2 = false;

bool checkLimit(int val, int limit, byte pin, bool &flag) {
  bool triggered = val >= limit;
  if (triggered != flag) {
    digitalWrite(pin, flag = triggered);
    return true;
  }
  return false;
}

void setup() {
  pinMode(23, OUTPUT);  pinMode(22, OUTPUT);
  Serial.begin(115200);
  Serial.printf("Nominal: %d\nUL1: %.1fV (%d)\nUL2: %.1fV (%d)\n", 
                NOMINAL, 3.3/2*1.15, ULIMIT1, 3.3/2*1.30, ULIMIT2);
}

void loop() {
  int val = analogRead(36);
  float v = 3.3 * val / 4095;

  if (checkLimit(val, ULIMIT1, 23, u1))
    Serial.printf("%.1fV U1 %s\n", v, u1?"App":"Dis");

  if (checkLimit(val, ULIMIT2, 22, u2))
    Serial.printf("%.1fV U2 %s\n", v, u2?"App":"Dis");

  delay(1000);
}