void setup() {
  TCCR1A = 0;
  TCCR1B = 0;
  bitSet(TCCR1B, CS12);  // 256 prescaler
  OCR1A = 62500;
  bitSet(TCCR1A, COM1A0); // Toggle pin OC1A (9)
  pinMode(9, OUTPUT);
}

void loop() {
}

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