HW-201 Infrared Obstacle Avoidance Module

// HW-201 Infrared Obstacle Avoidance Module
// Reads the module's digital OUT pin and prints obstacle status to Serial.
// Many HW-201 modules are active-low: OUT goes LOW when an obstacle is detected.

const int sensorPin = 2;

void setup() {
  pinMode(sensorPin, INPUT);
  Serial.begin(9600);
  while (!Serial) {
    ;
  }
  Serial.println("HW-201 Infrared Obstacle Avoidance Module");
  Serial.println("Active-low output: LOW = obstacle detected, HIGH = no obstacle");
}

void loop() {
  int state = digitalRead(sensorPin);

  if (state == LOW) {
    Serial.println("Obstacle detected");
  } else {
    Serial.println("No obstacle");
  }

  delay(200);
}