Erreur

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Il suffit d'attendre que la coupure cesse avznt de continuer

void loop() {
 if (digitalRead(OPTO) == NOT_CUT) digitalWrite(ledPin, LOW); else digitalWrite(ledPin, HIGH);
 if (digitalRead(OPTO) == CUT) {    // Opto test
   count = count + 1;                      // Increment the count variable
   if (count == 3) count = 0;            // Resetting the variable count 2=>0
   if (count == 0){ 
      // motor stopped 
      digitalWrite(EN1, LOW);
      digitalWrite(EN2, LOW);
   }
   if (count == 1){
     // Motor forward
     digitalWrite(EN1, HIGH);
     digitalWrite(EN2, HIGH);
     myStepper.step(stepsPerRevolution);
   }
   if (count == 2){ 
    // Motor backward
    digitalWrite(EN1, HIGH);
    digitalWrite(EN2, HIGH);
    myStepper.step(-stepsPerRevolution);
  }
  while(digitalRead(OPTO) == CUT);  // On attends que la coupure disparaisse
 }
}