[euhlmann]

Originally Posted by ProfessorAlekM

Hello!

I've wrote UDP code to communicate with a beaglebone from the roboRIO, however when the I put on autonomous mode and the UDP is used none of the motors work, and when I change back to teleop I still can't control anything.

Here is the code:

public class Robot extends IterativeRobot {
	//Beaglebone Communications
    DatagramSocket serverSocket;
    byte[] receiveData;
    byte[] sendData;

Code for robot init

try {
			serverSocket = new DatagramSocket(9876);
		} catch (SocketException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
    	receiveData = new byte[1024];
        sendData = new byte[1024];

public void autonomousPeriodic() {
    	
    	//Receive Data
        DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
        try {
			serverSocket.receive(receivePacket);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        String sentence = new String( receivePacket.getData());
        System.out.println("RECEIVED: " + sentence);
        InetAddress IPAddress = receivePacket.getAddress();
        int port = receivePacket.getPort();

        //Return data
        String capitalizedSentence = sentence.toUpperCase();
        sendData = capitalizedSentence.getBytes();
        DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, port);
        try {
			serverSocket.send(sendPacket);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        
        switch (sentence) {
        	case "a":
        		myRobot.tankDrive(0.5, 0.5);
        	break;
        	
        	case "b":
        		myRobot.tankDrive(0,0);
        	break;
        }

        Timer.delay(0.005);

    }

Thanks for any help!

You may be running into a Java subtlety here.

boolean eq = ("abc" == "abc");
System.out.println(eq); // false!

I'm not entirely sure, but it may be the same problem in your switch statement. Try using String.equals in an if-else instead.

Otherwise, use the debugger to verify that sentence contains the "a" or "b" you need.