Serial check for arduino pwm

simplePWMSerial

int pwm;
const int controlPin=9;

String inString;    // string to hold input
int DisplayInfo=1;

void setup() {
  pinMode(controlPin, OUTPUT);
  Serial.begin(9600);
  pwm = 0;
  analogWrite(controlPin, pwm);
}


void loop() {

if(DisplayInfo)
  {
    inString="";
    Serial.print("PWM(0..100)?");
    DisplayInfo=0;
  }
  
  if(Serial.available() > 0) {
    int inChar = Serial.read();
    if (isDigit(inChar)) {
      // convert the incoming byte to a char and add it to the string:
      inString += (char)inChar;
    }
    // if you get a newline, print the string, then the string's value:
    if (inChar == '\n') {

      if(inString.length() > 0){
      int value=  inString.toInt();
      if((value < 0) || ( value >100)) 
         Serial.println("*** 0 à 100 ***");
       else
         {
          pwm = value * 255 / 100;
          analogWrite(controlPin, pwm);
          Serial.print(" PWM de ");
          Serial.print(value);
          Serial.println("% accepté");
          }
         DisplayInfo=1;
         
      }
    }
  }
}