Reporting low water level with the eTape

xmas-lights.2.ino

#define ETAPE A0

// Set crucial level as appropriate for your needs.
// For me, 687 indicates three inches of water.
#define CRUCIAL_LEVEL 687
#define LED_RED 13

float resistance;

void setup(void) {
  pinMode(LED_RED, OUTPUT);
  Serial.begin(9600);
}

void loop(void) {
  resistance = analogRead(ETAPE);
  Serial.println(resistance);
  
  if (resistance > CRUCIAL_LEVEL) {
    digitalWrite(LED_RED, HIGH);
  } else {
    digitalWrite(LED_RED, LOW);
  }
  
  delay(1000);
}