float value = 0;
boolean flip = false;

void setup()
{

 Serial.begin(9600);
}

void loop()
{
 if(value >= 1023)
 {
     flip = true;
 }else if(value <= 0)
 {
     flip = false;
 }

 if(flip == false)
 {
    value += 1;
 }else{
    value -= 1;
 }

 float values[] = {0,0,value};

 Serial.flush(); //clears any possible left over information
 Serial.print(map(values[0],0,1023,0,360)); //Resizes values from the range on arduino input to 360 of rotation.
 Serial.print(",");
 Serial.print(map(values[1],0,1023,0,360));
 Serial.print(",");
 Serial.print(map(values[2],0,1023,0,360));
 Serial.println();

 delay(10);
}

using UnityEngine;
using System.Collections;
using System.IO.Ports;

public class serialRotation : MonoBehaviour {

     SerialPort stream = new SerialPort("COM4", 9600); //Set the port (com4) and the baud rate (9600, is standard on most devices)
     float[] lastRot = {0,0,0}; //Need the last rotation to tell how far to spin the camera
     
     
     void Start () {
           stream.Open(); //Open the Serial Stream.
     }
     
     // Update is called once per frame
     void Update () {
           string value = stream.ReadLine(); //Read the information
           string[] vec3 = value.Split(','); //My arduino script returns a 3 part value (IE: 12,30,18)
           if(vec3[0] != "" && vec3[1] != "" && vec3[2] != "") //Check if all values are recieved
           {
                 transform.Rotate(                  //Rotate the camera based on the new values
                                               float.Parse(vec3[0])-lastRot[0],
                                               float.Parse(vec3[1])-lastRot[1],
                                               float.Parse(vec3[2])-lastRot[2],
                                               Space.Self
                                         );
                 lastRot[0] = float.Parse(vec3[0]);  //Set new values to last time values for the next loop
                 lastRot[1] = float.Parse(vec3[1]);
                 lastRot[2] = float.Parse(vec3[2]);
                 stream.BaseStream.Flush(); //Clear the serial information so we assure we get new information.
           }
     }
     
     void OnGUI()
     {
           string newString = "Connected: " + transform.rotation.x + ", " + transform.rotation.y + ", " + transform.rotation.z;
           GUI.Label(new Rect(10,10,300,100), newString); //Display new values
           // Though, it seems that it outputs the value in percentage O-o I don't know why.
     }
}