Problema Cliente/Servidor

Buenas! tengo un problema y es que me he creado un cliente/servidor muy simple. Lo que haría la app es pedir una cadena de caracteres por pantalla y al pulsar un botón enviarla al servidor pero me falla la conexión con el servidor. El mensaje que me aparece es el siguiente:

No command output when running: 'am start -n com.example.serverpillao/com.example.serverpillao.MainActivity -a android.intent.action.MAIN -c android.intent.category.LAUNCHER' on device emulator-5554

Este seria el MainActivity:

package com.example.serverpillao;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener{
public static final String SERVERIP = "192.168.1.255"; // 'Within' the emulator!
public static final int SERVERPORT = 80;
public TextView text1;
public EditText input;
public Button btn;
public boolean start;
public Handler Handler;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

text1=(TextView)findViewById(R.id.textView1);
input=(EditText)findViewById(R.id.editText1);
btn = (Button)findViewById(R.id.button1);
btn.setOnClickListener(this);
start=false;
new Thread(new Server()).start();
try {
Thread.sleep(500);
} catch (InterruptedException e) { }
new Thread(new Client()).start();
Handler = new Handler() {
@Override public void handleMessage(Message msg) {
String text = (String)msg.obj;
text1.append(text);
}
};
}

@SuppressLint("NewApi")
public class Client implements Runnable {
@Override
public void run() {
while(start==false)
{
}
try {
Thread.sleep(500);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
InetAddress serverAddr = InetAddress.getByName(SERVERIP);
updatetrack("Client: Start connecting\n");
DatagramSocket socket = new DatagramSocket();
byte[] buf;
if(!input.getText().toString().isEmpty())
{
buf=input.getText().toString().getBytes();
}
else
{
buf = ("Default message").getBytes();
}
DatagramPacket packet = new DatagramPacket(buf, buf.length, serverAddr, SERVERPORT);
updatetrack("Client: Sending '" + new String(buf) + "'\n");
socket.send(packet);
updatetrack("Client: Message sent\n");
updatetrack("Client: Succeed!\n");
} catch (Exception e) {
updatetrack("Client: Error!\n");
}
}
}
public class Server implements Runnable {

@Override
public void run() {
while(start==false)
{
}
try {
InetAddress serverAddr = InetAddress.getByName(SERVERIP);
updatetrack("\nServer: Start connecting\n");
DatagramSocket socket = new DatagramSocket(SERVERPORT, serverAddr);
byte[] buf = new byte[17];
DatagramPacket packet = new DatagramPacket(buf, buf.length);
updatetrack("Server: Receiving\n");
socket.receive(packet);
updatetrack("Server: Message received: '" + new String(packet.getData()) + "'\n");
updatetrack("Server: Succeed!\n");
} catch (Exception e) {
updatetrack("Server: Error!\n");
}
}
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
start=true;
}
public void updatetrack(String s){
Message msg = new Message();
String textTochange = s;
msg.obj = textTochange;
Handler.sendMessage(msg);
}

}




Y este el activity_main:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="ttp://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<requestFocus />
</EditText>

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Send" />

<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Communication History:"
android:textAppearance="?android:attr/textAppearanceLarge" />

</LinearLayout>


Al ejecutarlo me aparece el mensaje de Error! es decir, que entra en el catch (Exception e)
¿Alguien tiene idea de a qué se puede deber esto?
Muchas gracias de antemano.

Saludos.