#define POTENTIOMETER_PIN 35 // ESP32 pin GPIO35 (ADC0) connected to Potentiometer pin
#define BUZZER_PIN 21 // ESP32 pin GPIO21 connected to Buzzer's pin
#define ANALOG_THRESHOLD 1000
void setup() {
 pinMode(BUZZER_PIN, OUTPUT); // set ESP32 pin to output mode
} 
void loop() {
 int analogValue = analogRead(POTENTIOMETER_PIN); // read the input on analog pin
 if (analogValue > ANALOG_THRESHOLD)
 digitalWrite(BUZZER_PIN, HIGH); // turn on Piezo Buzzer
 else
 digitalWrite(BUZZER_PIN, LOW); // turn off Piezo Buzzer
}