arduino receive data from nodejs

serialport_test.ino

#define redPin *
#define greenPin *
#define bluePin *

int recieveByte = 0;
String bufStr = "";
String okStr = "OK";

void setup() {
  // init pins
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  bufStr = "";
  while (Serial.available() > 0) {
    recieveByte = Serial.read();
    if (recieveByte == (int)'\n') break;
    bufferStr.concat((char)recieveByte);
  }

  if (bufferStr.length() > 0) {
    analogWrite(redOin, );
  }

  delay(500);
  
}