#define BUZZLER_PIN 9
int light = 12;
int lbtn = 2;
int rbtn = 7;
int ubtn = 4;
int dbtn = 8;
void setup() {
  Serial.begin(14400);
  pinMode(BUZZLER_PIN, OUTPUT);
  pinMode(lbtn, INPUT);
  pinMode(rbtn, INPUT);
  pinMode(ubtn, INPUT);
  pinMode(dbtn, INPUT);
  pinMode(light, OUTPUT);
}
void loop() {
  String stringOne = ":=zero";
  if(!digitalRead(ubtn))
  {
    Serial.println(":=ubtn");
  }
  else if(!digitalRead(rbtn))
  {
    Serial.println(":=rbtn");
  }
  else if(!digitalRead(lbtn))
  {
    Serial.println(":=lbtn");
  }
  else if(!digitalRead(dbtn))
  {
    Serial.println(":=dbtn");
  }

  else
  {
    Serial.println(stringOne);
  }

  if (Serial.available() > 0)
  {

    char incomingChar = Serial.read();
    switch (incomingChar)
    {
      case '1':
        tone(BUZZLER_PIN, 3500, 100);
        delay(50);
        break;
      case '0':
      analogWrite(light, 0);
        break;
      case '2':
      analogWrite(light, 225);
        tone(BUZZLER_PIN, 60, 1000);
        delay(1000);
        tone(BUZZLER_PIN, 4000, 400);
        delay(400);
        break;
    }
  }

  delay(100);
}
------------------------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO.Ports;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Timers;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        List<Point> enemys = new List<Point>();
        Point player;
        SolidBrush sb = new SolidBrush(Color.Red);
        SolidBrush sbb = new SolidBrush(Color.Blue);
        Pen playerPen;
        Pen enemyPen;
        SerialPort currentPort;
        System.Timers.Timer aTimer;
        Graphics g;
        int pos;
        Random r = new Random(DateTime.Now.Millisecond);
        private delegate void updateDelegate(string txt);
        public Form1()
        {
            InitializeComponent();

        }
        int minD = 10000;
        private void Form1_Load(object sender, EventArgs e)
        {

            enemys.Add(new Point(420, 220));
            playerPen=new Pen(sb,5);
            enemyPen=new Pen(sbb,5);
            player = new Point(picResult.Width/2,picResult.Height/2);
            aTimer = new System.Timers.Timer(300);
            aTimer.Elapsed += OnTimedEvent;
            aTimer.AutoReset = true;
            aTimer.Enabled = true;
            currentPort = new SerialPort("COM5", 14400);
            currentPort.Open();
            g = picResult.CreateGraphics();


            new Task(
               () =>
               {
                   bool isGot = false;
                   int id = 0;
                   while (true)
                   {
                       isGot = false;
                       g.Clear(Color.White);
                       g.DrawEllipse(playerPen, new Rectangle(player.X - 5, player.Y - 5, 10, 10));
                       for (int i = 0; i < enemys.Count();++i )
                       {
                           int distance = (enemys[i].X - player.X) * (enemys[i].X - player.X) + (enemys[i].Y - player.Y) * (enemys[i].Y - player.Y);
                            if(minD>distance)
                            {
                                minD=distance;
                            }
                           g.DrawEllipse(enemyPen, new Rectangle(enemys[i].X - 5, enemys[i].Y - 5, 10, 10));
                           if (distance < 310)
                           {
                               isGot = true;
                               id = i;
                               lblResult.BeginInvoke(new updateDelegate(updateTextBox), "YOU GOT IT!!!");
                               break;

                               //MessageBox.Show("You lose!");
                               //Form1_FormClosed(this, new FormClosedEventArgs(CloseReason.None));
                           }
                       }
                       if(isGot)
                       {
                           enemys.RemoveAt(id);
                           if(enemys.Count()==0)
                           {
                               currentPort.Write("2");
                               MessageBox.Show("You win!");
                               currentPort.Write("0");
                               for (int i = 0; i < 4; ++i)
                               {
                                   enemys.Add(new Point(r.Next(0, picResult.Width), r.Next(0, picResult.Height)));
                               }
                              // Form1_FormClosed(this, new FormClosedEventArgs(CloseReason.None));
                           }
                       }
                       //lblResult.BeginInvoke(new updateDelegate(updateTextBox), (minD/50).ToString());
                       Thread.Sleep(50);
                       char val =(char) (30 + (minD/50));

                   }
               }
               ).Start();
        }
        private void OnTimedEvent(object sender, ElapsedEventArgs e)
        {
            if (!currentPort.IsOpen) return;
            try
            {
                g.Clear(Color.White);
                currentPort.DiscardInBuffer();

                string strFromPort = currentPort.ReadLine();

                if (strFromPort.Contains(":=lbtn"))
                {
                    lblResult.BeginInvoke(new updateDelegate(updateTextBox), "LEFT");
                    currentPort.Write("1");
                    player.X = player.X - 5;
                }
                else if (strFromPort.Contains(":=rbtn"))
                {
                   lblResult.BeginInvoke(new updateDelegate(updateTextBox), "RIGHT");
                    currentPort.Write("1");
                    player.X = player.X + 5;
                }
                else if (strFromPort.Contains(":=ubtn"))
                {
                   lblResult.BeginInvoke(new updateDelegate(updateTextBox), "UP");
                    currentPort.Write("1");
                    player.Y = player.Y - 5;
                }
                else if (strFromPort.Contains(":=dbtn"))
                {
                    lblResult.BeginInvoke(new updateDelegate(updateTextBox), "DOWN");
                    currentPort.Write("1");
                    player.Y = player.Y + 5;
                }
                else
                {
                    lblResult.BeginInvoke(new updateDelegate(updateTextBox), "NONE");
                }
                //lblPortData.Dispatcher.BeginInvoke(new updateDelegate(updateTextBox), strFromPort);
            }
            catch { }
        }
        private void updateTextBox(string txt)
        {
            lblResult.Text = txt;
        }

        private void Form1_FormClosed(object sender, FormClosedEventArgs e)
        {
            currentPort.Close();
        }
    }
}