Java desktop bluetooth client can not find services - java

I am new to bluetooth programming, so please keep that in mind.
I am trying to connect to a pulse sensor from a desktop pc, specifically the Zephyr HxM BT. I am not using any device specific drivers, the Java bluetooth library I'm using is Bluecove, and my bluetooth stack is BlueSoleil.
From my understanding, the way I proceed is
1) Scan for BT devices
public void startSearch() throws BluetoothStateException{
System.out.println("Inquiry started");
localdevice.getDiscoveryAgent().startInquiry(DiscoveryAgent.GIAC, this);
}
This works fine, it discovers my pulse belt and calls
public void deviceDiscovered(RemoteDevice arg0, DeviceClass arg1)
2) Search a device for services
Once a device has been discovered, it should be added to the DiscoveryAgent's list of cached devices, this is my first problem as the cache (and preknown devices) is always empty even though I've discovered my belt.
So the way that I do this now is to either keep my own list of devices, or simply start a service search directly from deviceDiscovered.
I am still a bit unsure if I'm using the correct parameters, but from reading the BT device manual and the javax.bluetooth documentation on DiscoveryAgent.searchServices:
public int searchServices(int[] attrSet,
UUID[] uuidSet,
RemoteDevice btDev,
DiscoveryListener discListener)
throws BluetoothStateException
My code:
public void searchServices(RemoteDevice device){
UUID[] uuidSet = new UUID[1];
uuidSet[0]=new UUID("1101",false); //Serial Port
System.out.println("Searching for services on " + device.getBluetoothAddress() );
try{
agent.searchServices(null,uuidSet, device,this);}
catch (BluetoothStateException e){
System.out.println("BluetoothStateException caught.");
}
}
I've set the attributes parameter to null, because the documentation states that this will have it search for services with the default attributes, however I've also tried to use only ServiceID (0x0003) as attribute with no luck.
This is where I'm stuck, I pass the correct BT device into the function, and it starts searching but never give me any results, it just searches forever for all I know, no exception, no calls to
public void servicesDiscovered(int arg0, ServiceRecord[] arg1)
or
public void serviceSearchCompleted(int arg0, int arg1)
So I guess my questions are:
- Am I doing something wrong? Any suggestions?
- What are the other approaches to connecting to a BT device, and what
information do I have to know about the device to do that?
Here is some information that I think is relevant from the device manual:
The following steps have to be undertaken to connect to a HxM device.
1) Activate the Bluetooth service of the device/computer wanting to connect to the HxM
2) Scan for Bluetooth devices in range
3) Pair with the HxM device found in range
4) Discover Services of Paired HxM
5) Connect to serial port of HxM device
The diagram above shows that the Bluetooth HxM typically communicates with a mobile device over the Bluetooth
link. The HxM only supports one link at a time and uses the Bluetooth SPP (Serial Port Profile) to communicate
with other devices with the following low-level protocol:
• 115,200 baud
• 8 data bits
• 1 stop bit
• No parity
Any suggestions are very much appreciated
edit: I just want to add that I'm testing the code with a console input loop, so the program is not immediately terminated after calling searchServices, it should have time to complete unless I'm misunderstanding async tasks

I just wanted to update this and say that I found the problem, it seems that I had to use a short UUID instead of a long. I should have tried both of these options before I deemed myself stuck, but I didn't think it would make any difference.

Related

How to connect with a Bluetooth device without pairing

I'm currently developping my first app in java.
This app requires a direct connection with my BL652, which doesn' t accept any kind of pairing option. That being said, I'm stuck with the code below, which still tries to pair with my bluetooth device instead of just connecting. Therefore, I wanted to know what am i supposed to do in order to make a connection that doesnt require pairing.
Thanks in advance for any response.
String mac_address = "DA:72:21:29:0F:F0";
private static final UUID MY_UUID = UUID.fromString("E54B0002-67F5-479E-8711-B3B99198CE6C");
lvNewDevices.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
BluetoothDevice device = (BluetoothDevice) mBluetoothAdapter.getRemoteDevice(mac_address);
try {
socket = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
socket.connect();
} catch (IOException e) {
e.printStackTrace();
}
I'm not sure about connection to external hardware but it's definetly possible to connect 2 phones without pairing. I made it using Android Nearby Connections . And yeah it's basically working with BLE. As far as I know it's possible to connect to RaspberryPi using that API.
Bluetooth devices can be made to communicate with each other using master-slave configuration. I first tried with two BLE-HC05s, made one as master and the other as slave, and as expected the master is able to send data, slave is able to receive data, that can be seen using the Serial Monitor in Arduino IDE. I have developed a similar app, which connects to a BLE-HC05 device, sends and receives data. But since you are trying to get data or send data to the App on your phone, Android will not support such unpaired anonymous communications. If you are having trouble with connection or pairing Bluetooth device and your app, I may help you with that. But as far as Bluetooth communication without pairing is concerned, you may not be able to find a way.
Edit: The code to connect any bluetooth device, like BLE-HC06 as you have mentioned, is 1234 (Only if you have not changed it)

Using kura framework, how can I specify the address type to "random static" when connecting to a BLE device

I'm trying to create an OSGi bundle that'd be installed on a eurotech gateway (reliagate 10 05).
This bundle would essentially connect the gateway to a BLE device.
To do so, I use a framework provided by eurotech called Everyware™ Software Framework (ESF) that adds up an extra layer on top of the kura v1.2.0 framework.
The catch is, the BLE device only accepts random static address type.
I managed to connect the gateway manually to the BLE device using the following commands in console:
hcitool -i hci0 lecc --random <BD_ADDR>
then
gatttool -i hci0 -b <BD_ADDR> --interactive
This works fine. The hard part is when I try to do the same thing in code using the ESF/kura framework.
Here's a snippet from a sample I use that I found on this page
public boolean connect(String adapterName) {
this.bluetoothGatt = this.device.getBluetoothGatt();
boolean connected = false;
try {
connected = this.bluetoothGatt.connect(adapterName);
} catch (KuraException e) {
logger.error(e.toString());
}
if (connected) {
this.bluetoothGatt.setBluetoothLeNotificationListener(this);
this.isConnected = true;
return true;
} else {
// If connect command is not executed, close gatttool
this.bluetoothGatt.disconnect();
this.isConnected = false;
return false;
}
}
Here is a list of some objects that the sample uses to scan and establish a connection:
org.eclipse.kura.bluetooth.BluetoothAdapter;
org.eclipse.kura.bluetooth.BluetoothDevice;
org.eclipse.kura.bluetooth.BluetoothGattSecurityLevel;
org.eclipse.kura.bluetooth.BluetoothGattService;
org.eclipse.kura.bluetooth.BluetoothLeScanListener;
org.eclipse.kura.bluetooth.BluetoothService;
org.eclipse.kura.bluetooth.BluetoothDevice;
org.eclipse.kura.bluetooth.BluetoothGatt;
org.eclipse.kura.bluetooth.BluetoothGattCharacteristic;
org.eclipse.kura.bluetooth.BluetoothLeNotificationListener;
So I searched through the api doc but didn't find anything.
Though, one interesting SO post mentions a command code to send to the device.
I found a method in kura framework that might help.
Here's the signature:
void ExecuteCmd(java.lang.String ogf, java.lang.String ocf, java.lang.String parameter)
but I couldn't figure out the OpCode Group Field (ogf) associated to the OpCode Command Field(ocf) in any documentation (I skimmed the ~2300 pages of the Bluetooth 4.0 core spec). If anyone knows where to search... :)
In the end, the question is: is there a way to set the address type to random (as with the hcitool command) with the kura framework ?
Or am I totally misleaded ? :/
Anyway, I'm really new to the kura and ble ecosystems so, sorry if it looks like an obvious thing to do but I feel like I'm running out of inspiration and could totally use a hand!
PS: Congrats if you made it to the end!
Haha lol. Kura seems to just start a gatttool process, send commands in text, and parse the output as its interface...
Here is where it is stated, using the address as parameter: https://github.com/eclipse/kura/blob/0339ac787f90debdfc270c1dee0c16de16ea6f7e/kura/org.eclipse.kura.linux.bluetooth/src/main/java/org/eclipse/kura/linux/bluetooth/util/BluetoothUtil.java#L319. Unfortunately the Kura developers seem to have missed that there is something called Random Address in the BLE standard and I don't see how that could be worked around using the current API.
Okay so for those who find themselves in my position in the future, I just received an answer from the Eurotech support team.
Dear Mr. Carneiro,
[...]
Regarding the random BD_ADDR, this is a configuration of the BLE device.
So, your BLE device is advertising an address of type random, not public, and you should specify the address type on the connection string, as you already did.
Unfortunately, current Kura Bluetooth API doesn't provide a way to specify the type of address into the connection string. We are developing a new set of APIs for BLE that will be available on preview on the next Kura/ESF release, but the Reliagate 10-05 will not support these yet.

Arduino HC-05 Bluetooth module disconnects when sending data

I'm new to Arduino. I'm trying to build a program to control a breadboard through Arduino using the bluetooth module HC-05. At the moment I don't have anything on the breadboard and I'm just trying to test the connection. This is what I've done so far:
I put the module on the breadboard and I've paired it with the computer. When it's paired, the red led starts blinking slowly. I've connected the bluetooth Rx to Arduino Tx and Arduino Rx to bluetooth Tx following this tutorial: http://playground.arduino.cc/Learning/Tutorial01
I've also implemented both Java and Arduino programs following that tutorial. Here they are:
JAVA
public class Arduino extends PApplet{
public void connect(){
String[] serials = Serial.list();
Serial port = new Serial(this, Serial.list()[0], 9600);
port.write('H');
port.dispose();
}
ARDUINO
void setup() {
Serial.begin(9600);
Serial.println("Start");
}
void loop() {
if(Serial.available()){
int a = Serial.read();
Serial.print(a);
}
}
The Java part should send the letter H to Arduino and Arduino should detect that and print it on the Serial monitor. But what actually happens is that I send data, and the led on the HC-05 starts blinking faster (which means the connection is lost). Why does that happen? I'm pretty confused. For the communication I'm using the port COM6 and COM7. It depends on how it connects. To see what port to use I just run the Java program: if the port is not correct, it will just get stuck and send nothing.
Any help is appreciated. Thanks!
In the end, I've solved this problem by removing this line of code:
port.dispose();
It would never work with it because I was getting rid of the connection. I don't know what I was thinking at the time I did that. That was very silly of me.
Ok so I had this problem.
If you are using the L293D motor shield, you'll be running the arduino of the same power supply, which I think must affect the power output the the bluetooth HC05 module.
Take out the jumper plug on the L293D motor shield, and run the arduino of a separate power source (e.g PP3 battery) and the problem disappears, OK.

Detect Beacon (Eddystone) with Android Nearby API

I'm trying to detect beacons around me, but with the Nearby API, i can't seem to find them.
I'm using this method to detect nearby devices :
public void startDiscovery(String serviceId, final OnDiscoveryListener l) {
Nearby.Connections.startDiscovery(googleApiClient, serviceId, Connections.DURATION_INDEFINITE, new Connections.EndpointDiscoveryListener() {
#Override
public void onEndpointFound(String endpointId, String deviceId, String serviceId, String endpointName) {
if (l != null) {
l.onEndpointFound(endpointId, deviceId, serviceId, endpointName);
}
}
#Override
public void onEndpointLost(String s) {
if (l != null) {
l.onEndpointLost(s);
}
}
})
.setResultCallback(new ResultCallback<Status>() {
#Override
public void onResult(Status status) {
if (l != null) {
l.onResult(status);
}
}
});
}
The listener looks like this :
public interface OnDiscoveryListener {
public void onResult(Status status);
public void onEndpointFound(String endpointId, String deviceId, String serviceId, String endpointName);
public void onEndpointLost(String s);
}
But i can't detect anything
I work on the Nearby API at Google. The code snippet above uses the Nearby Connections API--which is actually geared towards different use-cases. To work with Eddystone, use the Nearby Messages API. Here's an example of using Nearby Messages to subscribe to the presence of beacons
Note that you need to first associate a Message payload with the beacon using the Proximity Beacon API.
Even though Google advertised the usage of the Nearby API to detect beacons around us :
The Nearby API for Android and iOS makes it easier for apps to find and communicate with nearby devices and beacons
Source : http://android-developers.blogspot.be/2015/07/lighting-way-with-ble-beacons.html
I wasn't able to use the Nearby API to detect Eddystone beacons. I will describe bellow all the information I have gathered during my research hoping this might save some people some time.
I had setup about the same code as you to detect Estimote beacons but I wasn't able to find the Service ID to provide to Nearby.Connections.startDiscovery() to make it detect my beacon (I tried to use the beacon UUID and some variants without success).
I found on Estimote's website that you need to update the beacon firmware to be able to configure it as an Eddystone beacon : http://developer.estimote.com/eddystone/#configure-estimote-beacons-to-broadcast-eddystone. Mine wasn't so I did it.
Nevertheless, that didn't solve my problem and I was still unable to detect the beacon using the Nearby API. I tried setting it as a Eddystone-UID and a Eddystone-URL and tried several combination (based on the information provided by the Estimote app) as Service ID unsuccessfully.
A more deeper look into the Nearby API's documentation shows that Google doesn't mention anything about beacons nor Eddystone in their Nearby API documentation (https://developers.google.com/nearby/connections/overview) and Google's sample about beacons is not using the Nearby API at all : https://github.com/google/beacon-platform/tree/master/samples/android
Yet, they do mention that Nearby Messages will allow rich interaction such as "collaborative editing, forming a group, voting, or broadcasting a resource" and is coming soon :
Coming Soon: The Nearby Messages API will be available in Google Play service 7.8. This site will be updated with the complete API documentation when the new version is available.
Source : https://developers.google.com/nearby/
My understanding is the support for beacons will be available with the Google Play Services 7.8 since the beacons are broadcasting resources.
In the meantime, if you still wish to be able to detect Eddystone beacons around you, you can use Estimote's Android SDK : https://github.com/estimote/android-sdk#quick-start-for-eddystone
or implement the same code as Google's Beacon Proximity sample :
https://github.com/google/beacon-platform/tree/master/samples/android
This may sound like an odd thing - but try turning you wifi on and off. A lot of cheaper devices are really bad with bluetooth and fail to connect, but for some reason turning wifi off and on fixes it for a while.
I was having a similar problem - everything in my code was correct but not detecting beacons. I even tried with the manufacturers app, and theirs also couldn't detect the beacon (but their iPhone version did). I turned my wifi off, then back on again and the manufacturers app worked and so did mine.
Yes, you can discover Eddystone beacons using the Nearby API. But to detect beacons you have to use the Nearby Messages API not the Nearby Connections API, as #Andrew Bunner also mentions.
To be able to detect the beacons using NearbyMessagesAPI you will have to also register the beacons with Google first, and than configure them to have a message payload associated with them.
You can find all the steps in my blog post or this other answer I posted.

How can I emulate a COM port, write data to it and read data from it?

I'm trying to test my code that reads from a USB port (COM25 when the device is connected) that is created when a device is connected to my computer and to a boat. I cannot power the USB device when not on the boat so testing is difficult. Can someone let me know how to simulate a COM port and write data to it so my test program is able to connect to that simulated COM port and read that data?
I'm reading this from a Java program but the simulation doesn't need to be in Java or any specific language. Just a program that will simulate the COM port and allow me to connect to it. I downloaded a COM port emulator from AGG Software and it appears that it's writing to what I deem COM25 but I'm not able to connect to it from my Java test.
The general answer for this kind of problem is to wrap the code that talks to the COM port in a class that implements an interface. If you do this as a Facade (pattern) then you can also make the COM methods you call sensible from your end.
The interface can then be mocked or faked for the test. (There is a great article on test objects, but I haven't been able to find it yet.) One advantage here is that you can create a fake version that throws exceptions or otherwise does things that are possible for the port to do but hard to get it to do in practice.
Where I work, we solved a similar issue by having our emulator not spoof a COM port at all. Here's how you can do it:
Define an interface for talking with your COM port, something like IUsbCommService
Implement your real COM-communcation service, using the standard Java Comm API
For your emulator, simply kick of a thread that spits out the same sort of data you can expect from your USB device at regular intervals.
Use your IOC framework of choice (e.g., Spring) to wire up either the emulator or the real service.
As long as you hide your implementation logic appropriately, and as long as you code to your interface, your service-consumer code won't care whether it's talking to the real USB device or to the emulator.
For example:
import yourpackage.InaccessibleDeviceException;
import yourpackage.NoDataAvailableException;
public interface IUsbProviderService {
public void initDevice() throws InaccessibleDeviceException;
public UsbData getUsbData()
throws InaccessibleDeviceException, NoDataAvailableException;
}
// The real service
import javax.comm.SerialPort; //....and the rest of the java comm API
public class UsbService implements IUsbProviderService {
.
.
.
}
// The emulator
public class UsbServiceEmulator implements IUsbProviderService {
private Thread listenerThread;
private static final Long WAITTIMEMS = 10L;
private String usbData;
public UsbServiceEmulator(long maxWaitTime) throws InaccessibleDeviceException{
initialize();
boolean success = false;
long slept = 0;
while (!success && slept < maxWaitTime) {
Thread.sleep(WAITTIMEMS);
slept += WAITTIMEMS;
}
}
private void initialize() throws InaccessibleDeviceException{
listenerThread = new Thread();
listenerThread.start();
}
private class UsbRunner implements Runnable {
private String[] lines = {"Data line 1", "Data line 2", "Data line 3"};
public void run() {
int line = 0;
while(true) {
serialEvent(lines[line]);
if(line == 3) {
line = 0;
} else {
line++;
}
try {
Thread.sleep(200);
} catch (InterruptedException e) {
//handle the error
}
}
private void serialEvent(String line) {
if(/*you have detected you have enough data */) {
synchronized(this) {
usbData = parser.getUsbData();
}
}
}
}
Hope this helps!
Thanks to all the answers so far! Here's what I ended up doing as a result of recommendations from someone at work.
Downloaded the COM Port Data Emulator (CPDE) from AGG Software
Downloaded the Virtual Serial Port Driver (VSPD) from Eltima Software
(I just randomly picked a free data emulator and virtual serial port package. There are plenty of alternatives out there)
Using VSPD, created virtual serial ports 24 and 25 and connected them via a virtual null modem cable. This effectively creates a write port at 24 and a read port at 25.
Ran the CPDE, connected to 24 and started writing my test data.
Ran my test program, connected to 25 and was able to read the test data from it
There are plenty of relevant answers in this section. But as for me, I personally use Virtual Serial Port Driver, which works perfect for me. But I must admit that there are plenty alternatives when it comes to creating virtual ports: freevirtualserialports.com; comOcom to name a few. But I haven't got a chance to use them, so my recommendation for solving this problem is Virtual Serial Port Driver.
I recommend fabulatech's virtual modem.
Get it at http://www.virtual-modem.com
You might also want to get a COM port monitor for your tests - You can find it at
http://www.serial-port-monitor.com
Good luck with the boat! :)
I use com0com and it works great for what I need.
In addition all others, I would like to added this nice, free emulator https://sites.google.com/site/terminalbpp/ I do use. I do also use AGG Com port data emulator.

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