Databases
StackOverflow2013
Postsdbo
POI can't send UDP packet from Android to Arduino
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POI can't send UDP packet from Android to Arduino
    primarykey
    data
    text
    <p>I am trying to send UDP packets from Android app to Arduino using Wifi Shield, but I can't, it throws an exception (Ex3). I want to communicate an Android phone with Arduino, to send commands with this Shield. </p> <p>Here is the Android code:</p> <pre><code>public class MainActivity extends Activity { String udpMsg = "hello world from UDP client "; DatagramSocket ds = null; Button bt; TextView tv; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); bt = (Button) findViewById(R.id.myButton); tv = (TextView) findViewById(R.id.myTextView); runUdpClient(); } private static final int UDP_SERVER_PORT = 1050; private void runUdpClient() { Toast.makeText(getApplicationContext(), "E", Toast.LENGTH_SHORT).show(); bt.setOnClickListener(new OnClickListener() { public void onClick(View v) { try { EditText et = (EditText) findViewById(R.id.EditText01); String str = et.getText().toString(); ds = new DatagramSocket(); InetAddress serverAddr = InetAddress.getByName("192.168.1.16"); DatagramPacket dp; dp = new DatagramPacket(str.getBytes(), udpMsg.length(), serverAddr, UDP_SERVER_PORT); dp.setData(str.getBytes()); ds.send(dp); Log.d("Ok","Ok"); } catch (SocketException e) { Toast.makeText(getApplicationContext(), "Ex", Toast.LENGTH_SHORT).show(); e.printStackTrace(); } catch (UnknownHostException e) { Toast.makeText(getApplicationContext(), "Ex1", Toast.LENGTH_SHORT).show(); e.printStackTrace(); } catch (IOException e) { Toast.makeText(getApplicationContext(), "Ex2", Toast.LENGTH_SHORT).show(); e.printStackTrace(); } catch (Exception e) { Toast.makeText(getApplicationContext(), "Ex3", Toast.LENGTH_SHORT).show(); e.printStackTrace(); } finally { if (ds != null) { ds.close(); } } } }); } } </code></pre> <p>And this is the Arduino code:</p> <pre><code>include &lt;SPI.h&gt; include &lt;WiFi.h&gt; include &lt;WiFiUdp.h&gt; char ssid[] = "MySSid"; char pass[] = "00000000"; int status = WL_IDLE_STATUS; unsigned int localPort = 1050; // local port to listen on char packetBuffer[255]; //buffer to hold incoming packet char ReplyBuffer[] = "acknowledged"; // a string to send back WiFiUDP Udp; void setup() { //Initialize serial and wait for port to open: Serial.begin(9600); while (!Serial) { ; // wait for serial port to connect. Needed for Leonardo only } // check for the presence of the shield: if (WiFi.status() == WL_NO_SHIELD) { Serial.println("WiFi shield not present"); // don't continue: while(true); } // attempt to connect to Wifi network: while ( status != WL_CONNECTED) { Serial.print("Attempting to connect to SSID: "); Serial.println(ssid); // Connect to WPA/WPA2 network. Change this line if using open or WEP network: status = WiFi.begin(ssid); // wait 10 seconds for connection: delay(10000); } Serial.println("Connected to wifi"); printWifiStatus(); Serial.println("\nStarting connection to server..."); // if you get a connection, report back via serial: Udp.begin(localPort); } void loop() { // if there's data available, read a packet int packetSize = Udp.parsePacket(); if(packetSize) { Serial.print("Received packet of size "); Serial.println(packetSize); Serial.print("From "); IPAddress remoteIp = Udp.remoteIP(); Serial.print(remoteIp); Serial.print(", port "); Serial.println(Udp.remotePort()); // read the packet into packetBufffer int len = Udp.read(packetBuffer,255); if (len &gt;0) packetBuffer[len]=0; Serial.println("Contents:"); Serial.println(packetBuffer); // send a reply, to the IP address and port that sent us the packet we received /* Udp.beginPacket(Udp.remoteIP(), Udp.remotePort()); Udp.write(ReplyBuffer); Udp.endPacket();*/ } } void printWifiStatus() { // print the SSID of the network you're attached to: Serial.print("SSID: "); Serial.println(WiFi.SSID()); // print your WiFi shield's IP address: IPAddress ip = WiFi.localIP(); Serial.print("IP Address: "); Serial.println(ip); // print the received signal strength: long rssi = WiFi.RSSI(); Serial.print("signal strength (RSSI):"); Serial.print(rssi); Serial.println(" dBm"); } </code></pre> <p>I think the problem is in <strong>ds.send(dp);</strong></p> <p>Here is the stacktrace:</p> <pre><code>06-23 13:24:03.896: W/System.err(5915): java.lang.IllegalArgumentException 06-23 13:24:03.897: W/System.err(5915): at java.net.DatagramPacket.setData(DatagramPacket.java:183) 06-23 13:24:03.898: W/System.err(5915): at java.net.DatagramPacket.&lt;init&gt;(DatagramPacket.java:75) 06-23 13:24:03.898: W/System.err(5915): at java.net.DatagramPacket.&lt;init&gt;(DatagramPacket.java:97) 06-23 13:24:03.898: W/System.err(5915): at java.net.DatagramPacket.&lt;init&gt;(DatagramPacket.java:118) 06-23 13:24:03.898: W/System.err(5915): at com.example.arduino.Arduino$1.onClick(Arduino.java:52) 06-23 13:24:03.899: W/System.err(5915): at android.view.View.performClick(View.java:3517) 06-23 13:24:03.899: W/System.err(5915): at android.view.View$PerformClick.run(View.java:14155) 06-23 13:24:03.900: W/System.err(5915): at android.os.Handler.handleCallback(Handler.java:605) 06-23 13:24:03.900: W/System.err(5915): at android.os.Handler.dispatchMessage(Handler.java:92) 06-23 13:24:03.901: W/System.err(5915): at android.os.Looper.loop(Looper.java:154) 06-23 13:24:03.901: W/System.err(5915): at android.app.ActivityThread.main(ActivityThread.java:4624) 06-23 13:24:03.902: W/System.err(5915): at java.lang.reflect.Method.invokeNative(Native Method) 06-23 13:24:03.902: W/System.err(5915): at java.lang.reflect.Method.invoke(Method.java:511) 06-23 13:24:03.902: W/System.err(5915): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:809) 06-23 13:24:03.903: W/System.err(5915): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:576) 06-23 13:24:03.903: W/System.err(5915): at dalvik.system.NativeStart.main(Native Method) </code></pre> <p>Thank you.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USBrad Larson
    1. USuser2512569
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COPlease detail from which line of code the exception is being thrown, what exception is being thrown and anything else that might be pertinent to this problem...
      singulars
      1. POI can't send UDP packet from Android to Arduino
      1. UST I
    2. COThe exception that is being thrown is: catch (Exception e) { Toast.makeText(getApplicationContext(), "Ex3", Toast.LENGTH_SHORT).show(); e.printStackTrace(); Because, I see the toast "Ex3". Maybe is a problem with socket. Anyway, I am not sure if it's correct this way to communicate both devices (using the Wifi Shield).
      singulars
      1. POI can't send UDP packet from Android to Arduino
      1. USuser2512569
    3. COplease show us the stacktrace
      singulars
      1. POI can't send UDP packet from Android to Arduino
      1. USGreyBeardedGeek
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload