Arduino: How to use KY-037 High Sensitivity Sound Detection Module

				
					const int DIGITAL_PIN = 7; // D0 Output
const int ANALOG_PIN = A0; // A0 Output
const int LED_PIN = 13;    // Built-in LED

// Variables for monitoring the analog reading (Peak Amplitude)
const int CENTER_VALUE = 512; // Nominal ADC value (quiet)
int maxVolume = 0;
int minVolume = 1023;
int peakAmplitude = 0;

void setup() {
  pinMode(LED_PIN, OUTPUT);
  pinMode(DIGITAL_PIN, INPUT);
  Serial.begin(9600);
  Serial.println("KY-037 Sound Sensor Ready! Calibrate Digital Threshold.");
}

void loop() {
  // --- 1. Analog Reading (A0) - Find Peak-to-Peak Amplitude ---
  // Read 100 samples quickly to capture the waveform's peak and trough
  maxVolume = CENTER_VALUE;
  minVolume = CENTER_VALUE;
 
  // Quick 10ms sampling window
  long startTime = millis();
  while(millis() - startTime < 10) {
    int raw = analogRead(ANALOG_PIN);
    if (raw > maxVolume) {
      maxVolume = raw;
    } else if (raw < minVolume) {
      minVolume = raw;
    }
  }

  // Peak Amplitude is the range of the captured waveform
  peakAmplitude = maxVolume - minVolume;

  // --- 2. Read Digital State (D0) ---
  // Active LOW typically means noise detected (crossed the threshold)
  int digitalState = digitalRead(DIGITAL_PIN);

  // Control LED based on Digital Output (Action Trigger)
  if (digitalState == LOW) {
    digitalWrite(LED_PIN, HIGH); // Turn LED ON (Sound Detected)
  } else {
    digitalWrite(LED_PIN, LOW);  // Turn LED OFF (Quiet)
  }

  // Print both outputs to the Serial Monitor
  Serial.print("Analog (Amplitude): ");
  Serial.print(peakAmplitude);
  Serial.print(" | D0 State: ");
 
  if (digitalState == LOW) {
    Serial.println(">>> NOISE TRIGGERED (LOW) <<<");
  } else {
    Serial.println("QUIET (HIGH)");
  }
 
  delay(100);
}