This is example of bacnet4j 3.2.4 api usage to interact with Komfovent C4/Ping module to read present values og gauges and also set mode.

bacnet4j.java

import com.serotonin.bacnet4j.event.DeviceEventAdapter;
import com.serotonin.bacnet4j.exception.BACnetException;
import com.serotonin.bacnet4j.exception.ErrorAPDUException;
import com.serotonin.bacnet4j.npdu.ip.IpNetwork;
import com.serotonin.bacnet4j.service.acknowledgement.ReadPropertyAck;
import com.serotonin.bacnet4j.service.acknowledgement.ReadPropertyMultipleAck;
import com.serotonin.bacnet4j.service.confirmed.*;
import com.serotonin.bacnet4j.service.unconfirmed.WhoIsRequest;
import com.serotonin.bacnet4j.transport.DefaultTransport;
import com.serotonin.bacnet4j.transport.Transport;
import com.serotonin.bacnet4j.type.constructed.ReadAccessResult;
import com.serotonin.bacnet4j.type.constructed.ReadAccessSpecification;
import com.serotonin.bacnet4j.type.constructed.SequenceOf;
import com.serotonin.bacnet4j.type.enumerated.ObjectType;
import com.serotonin.bacnet4j.type.enumerated.PropertyIdentifier;
import com.serotonin.bacnet4j.type.enumerated.Segmentation;
import com.serotonin.bacnet4j.type.primitive.ObjectIdentifier;
import com.serotonin.bacnet4j.type.primitive.Real;
import com.serotonin.bacnet4j.util.DiscoveryUtils;

import java.util.ArrayList;
import java.util.List;

/**
 * @author Łukasz Dywicki <luke@code-house.org>
 */
public class Main {


    public static void main(String[] args) throws Exception {

        IpNetwork network = new IpNetwork("192.168.2.255", IpNetwork.DEFAULT_PORT);
        Transport transport = new DefaultTransport(network);
        transport.setTimeout(500000);
        transport.setSegTimeout(15000);
        final LocalDevice localDevice = new LocalDevice(1338, transport);

        localDevice.getEventHandler().addListener(new DeviceEventAdapter() {
            @Override
            public void iAmReceived(RemoteDevice device) {
                System.out.println("Discovered device " + device);
                localDevice.addRemoteDevice(device);

                final RemoteDevice remoteDevice = localDevice.getRemoteDevice(device.getAddress());

                remoteDevice.setSegmentationSupported(Segmentation.segmentedBoth);
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        try {
                            try {
                                DiscoveryUtils.getExtendedDeviceInformation(localDevice, remoteDevice);
                            } catch (BACnetException e) {
                                e.printStackTrace();
                            }
                            System.out.println(remoteDevice.getName() + " " + remoteDevice.getVendorName() + " " + remoteDevice.getModelName() + " " + remoteDevice.getAddress() + " " + remoteDevice.getProtocolRevision() + " " + remoteDevice.getProtocolVersion());

                            ReadPropertyAck ack = localDevice.send(remoteDevice, new ReadPropertyRequest(remoteDevice.getObjectIdentifier(), PropertyIdentifier.objectList)).get();
                            SequenceOf<ObjectIdentifier> value = ack.getValue();

                            for (ObjectIdentifier id : value) {

                                List<ReadAccessSpecification> specs = new ArrayList<ReadAccessSpecification>();
                                specs.add(new ReadAccessSpecification(id, PropertyIdentifier.presentValue));
                                specs.add(new ReadAccessSpecification(id, PropertyIdentifier.units));
                                specs.add(new ReadAccessSpecification(id, PropertyIdentifier.objectName));
                                specs.add(new ReadAccessSpecification(id, PropertyIdentifier.description));
                                specs.add(new ReadAccessSpecification(id, PropertyIdentifier.objectType));
                                ReadPropertyMultipleRequest multipleRequest = new ReadPropertyMultipleRequest(new SequenceOf<ReadAccessSpecification>(specs));

                                ReadPropertyMultipleAck send = localDevice.send(remoteDevice, multipleRequest).get();
                                SequenceOf<ReadAccessResult> readAccessResults = send.getListOfReadAccessResults();

                                System.out.print(id.getInstanceNumber() + " " + id.getObjectType() + ", ");
                                for (ReadAccessResult result : readAccessResults) {
                                    for (ReadAccessResult.Result r : result.getListOfResults()) {
                                        System.out.print(r.getReadResult() + ", ");
                                    }
                                }
                                System.out.println();
                            }

                            ObjectIdentifier mode = new ObjectIdentifier(ObjectType.analogValue, 11);

                            ServiceFuture send = localDevice.send(remoteDevice, new WritePropertyRequest(mode, PropertyIdentifier.presentValue, null, new Real(2), null));
                            System.out.println(send.getClass());
                            System.out.println(send.get().getClass());

                        } catch (ErrorAPDUException e) {
                            System.out.println("Could not read value " + e.getApdu().getError() + " " + e);
                        } catch (BACnetException e) {
                            e.printStackTrace();
                        }

                    }
                }).start();
            }

            @Override
            public void iHaveReceived(RemoteDevice device, RemoteObject object) {
                System.out.println("Value reported " + device + " " + object);
            }
        });

        localDevice.initialize();
        localDevice.sendGlobalBroadcast(new WhoIsRequest());

        List<RemoteDevice> remoteDevices = localDevice.getRemoteDevices();
        for (RemoteDevice device : remoteDevices) {
            System.out.println("Remote dev " + device);
        }

        System.in.read();
        localDevice.terminate();
    }

}