unity3D和串口之间的通信，接收下位机数据和发送指令

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

public class PortControl : MonoBehaviour {
public GUIText gui;
public string portName = "COM2";
public int baudRate = 9600;
public Parity parity = Parity.None;
public int dataBits = 8;
public StopBits stopBits = StopBits.One;

int[] data = new int[6];//用于存储6位数据
SerialPort sp = null;
Thread dataReceiveThread;
//发送
string message = "";
//byte[] message=new byte[8];
void Start()
{
OpenPort();
dataReceiveThread = new Thread(new ThreadStart(DataReceiveFunction));
dataReceiveThread.Start();
}

void Update()
{
string str = "";
for(int i=0; i<data.Length; i++)
{
str += data[i].ToString() + " ";
}
gui.text = str;
Debug.Log(str);
}

public void OpenPort()
{
sp = new SerialPort(portName, baudRate, parity, dataBits, stopBits);
sp.ReadTimeout = 400;
try
{
sp.Open();
}
catch(Exception ex)
{
Debug.Log(ex.Message);
}
}

public void ClosePort()
{
try
{
sp.Close();
}
catch(Exception ex)
{
Debug.Log(ex.Message);
}
}

public void WriteData(string dataStr)
{
if(sp.IsOpen)
{
sp.Write(dataStr);
}

}

void OnApplicationQuit()
{
ClosePort ();
}


void DataReceiveFunction()
{
byte[] buffer = new byte[128];
int bytes = 0;
int flag0 = 0xFF;
int flag1 = 0xAA;
int index = 0;//用于记录此时的数据次序
while (true)
{
if (sp != null && sp.IsOpen)
{
try
{
bytes = sp.Read(buffer, 0, buffer.Length);
for(int i=0; i<bytes; i++)
{

if(buffer[i]==flag0 || buffer[i]==flag1)
{
index = 0;//次序归0
continue;
}
else
{
if(index>=data.Length) index = data.Length-1;//理论上不应该会进入此判断，但是由于传输的误码，导致数据的丢失，使得标志位与数据个数出错
data[index] = buffer[i];//将数据存入data中
index++;
}

}
}
catch (Exception ex)
{
if (ex.GetType() != typeof(ThreadAbortException))
{
Debug.Log(ex.Message);
}
}
}
Thread.Sleep(10);
}
}

void OnGUI()
{
message = GUILayout.TextField(message);
if(GUILayout.Button("Send Message"))
{
WriteData(message);
}
string by= "XX AA 03 31 20 51 00 00";
if (GUILayout.Button("Send",GUILayout.Height(50),GUILayout.Width(100)))
{
WriteData(by);
}
}

}