int microsecs = 0;
void setup() {
  microsecs++;
  pinMode(LED_BUILTIN, OUTPUT);
  Serial.begin(115200);
  TCCR1A = 0;
  TCCR1B = bit(CS10);
  TCNT1 = 0;
  delayMicroseconds(microsecs);
  unsigned int cycles = TCNT1;
  Serial.print("Cycles: ");
  Serial.println(cycles - 1);
  Serial.print("Microseconds: ");
  Serial.println((float)(cycles - 1) / 16);
}


void loop() {
}

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