#define LED1 23
#define BUT1 35

void setup() {
  // put your setup code here, to run once:
    pinMode(LED1, OUTPUT);
    pinMode(BUT1, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  static bool blink = false;
  if (blink) {
    digitalWrite(LED1, HIGH);
    delay(250); 
    digitalWrite(LED1, LOW);
    delay(250); 
  }
  if (digitalRead(BUT1) == LOW) {
      blink = !blink;
      delay(1000);
  }
  

}