void setup() {
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(23, OUTPUT);           // Red LED​
  pinMode(22, OUTPUT);           // Blue LED​
  pinMode(32, INPUT_PULLDOWN);   // Pushbutton​
}

void loop() {
  // Switch blue LED based on pushbutton​
  digitalWrite(23, digitalRead(32));

  // Toggle red LED every second​
  digitalWrite(22, !digitalRead(22));
  delay(1000);  // 1-second freeze​
}