My app automates stuff on the device, based on rules. So e.g. bluetooth device xyz connected - turn volume on. That works fine. However I want to extend it to include bluetooth low energy devices. Currently it only supports devices that I can also see as paired in the system's bluetooth settings.
Does anybody have an idea on how to monitor BTLE devices as well?
So I do not want to communicate with these devices myself, I just want to know if another application communicates with one (so receive a broadcast like with the classic BT devices).
Related
I am searching for some way that can connect to Bluetooth devices without pairing. Or at least make a connection first and then it does not need to be established all the time. Like how wearable devices work (i.e. mi band 6 or Huawei band 6). Can someone please guide me towards some helpful demo or documentation for this somewhere?
Also, I was wondering how was the security managed since my Bluetooth is always on to communicate to the wearable device. Though, turning off discoverability does not seem to create any issues in order to communicate with the device.
Most wearables nowadays use Bluetooth Low Energy (BLE), and with BLE you don't need to pair in order to exchange data - i.e. only a connection is needed. That being said, it is recommended to pair as the data exchanged between the wearable device and the phone will be encrypted, in addition to some other benefits in terms of privacy and security, Have a look at the links below that will go over connection/pairing in more detail:-
Should one create a bond with BLE device
The Ultimate Guide to Android Bluetooth Low Energy
Making Android BLE work
I'm trying to implement a Bluetooth (BLE) gateway into a project to transfer data between hardware and a mobile device with an application. The hardware is not unique, it could be mass produced with the controller having the same program flashed into it.
If 100 of the hardware product is made, powered up sitting side by side, what is the best way to set up the information that the BLE broadcasts to advertise so that it can be received by a mobile device, and only 1 hardware and mobile device can be connected at any time.
For example, if you have 3 of the same fitness tracking watches side by side, and you only want to connect to 1 of them, how do you distinguish which is which on say the phones bluetooth pairing menu.
Does each of the manufactured hardware need to have a unique ID that shows on the mobile device (eg ABC11, ABC112, ABC113 etc), and how do you program 100 unique programs into the hardware quickly.
On the other hand, should each of the hardware have the same ID broadcast, and then the user just hopes for the best if the correct hardware is paired.
(BTW, the hardware is an arduino based microcontroller using a BM70 BLE module. neither of which are intended to be modified by the user)
Assistance appreciated.
Thanks. Nunya
You do not have to manually program a different MAC addresses for each device, the BM70 module is the one that provides the BLE MAC address and they are supposed to have unique ones. Sometimes manufacturer recycle (reuse) the addresses, but I think the chance to hit a MAC twice with 100 devies is pretty low.
If your devices are all the same and use the same program they all offer and advertise the same BLE service. The service and containing characteristics are the feature that distinguishes your devices from other BLE devices. A true BLE device that does not also use Bluetooth Classic will not show up in your phones bluetooth settings or pairing menu. BLE requires a dedicated app where you scan for BLE devices and idealy filter for the special service you are using to only find your own devices.
To distinguish between 100 devices placed next to each other (if this even matters since they are all the same) you need to either read the MAC address and prit it on a label for each device or use some status LEDs to show the connection status on your arduino. If you connect to one device the LEDs could start blinking to show which device you are connected to.
I'm setting up a mobile application to support bluetooth communication between an android phone and one dual-mode bluetooth module. Two devices must init a BLE connection and transfer sound through HandsFree profile. At any time, two device must be able to re-establish these communications.
Should application shut down the Classic bluetooth process after sound transferring is done and always connect by BLE??
If I understood your question correctly, you don't need Bluetooth Low Energy (BLE) for your application. If you just want to transfer sound through the HandsFree profile, then this can be accomplished with classic Bluetooth alone and you can even turn BLE for the entirety of the application.
Please see this Android Developer page which gives a step-by-step guide on how to do this and provide sample code:-
https://developer.android.com/guide/topics/connectivity/bluetooth#Profiles
Finally, please note that for the most part BLE and classic Bluetooth are mutually exclusive; even though they are part of the same specification, they are like two different wireless technologies and in almost all cases your application will need one or the other, but not both. Please see this post for more details:-
Can a Bluetooth LE powered device discover a classic Bluetooth device and vice-versa?
I hope this helps.
I've built a dual mode Bluetooth device using the BT 121 from Silicon Labs. The device implements SPP over the classic connection. The device name of the classic node is "XYZ Classic". It also implements a custom service (128-bit UUID) in BLE. The device name of the BLE node is "XYZ_BLE". Both nodes have the same MAC address.
When pairing under 'Bluetooth' settings, sometimes I will see 'XYZ Classic' and sometimes I will see 'XYZ_BLE'. It seems random which one it will pair to but many Android devices I've tested have a tendency to want to pair to the classic node. After pairing, a connection over classic/SPP ALWAYS works. However, I can only connect to the custom service if paired to the BLE node. If paired to classic I can see non-custom BLE services but not my custom service. To summarize:
Function Classic Pairing BLE Pairing
Spp Works Works
Cust BLE Doesn't Work Works
When I pair in code (Android) the problem also happens despite the fact that I search for the devices named 'XYZ_BLE' and then pair to the device returned. I've looked but I can't see a way to force Android to pair to the BLE node.
My only workaround thus far has been to modify my BT 121 firmware to not allow bonding in classic mode. This is not an ideal solution has any Bluetooth Classic only devices will not be able to bond with my device (In reality this might not be too big of a problem but I have one tablet in my possession that only has Bluetooth Classic).
It should be noted that I've used 'BLE Scanner' from the play store to verify that my custom service works/doesn't work depending on the pairing mode. In other words, it's not just my code. :)
So, does anybody have any ideas on how to force Android to pair to the BLE node?
I see similar issues. Some hints:
Android behaviour differs dependent on the bit flags you set in the BLE advertising. There is for example a bit called "no br/edr support" or so. There are also bits telling explicitly that br/edr dual role is supported.
Also ble pairing may be enforced if you access a characteristic which returns a "not authenticated error" from a ble app. At least on iohone, the os will initiate the ble pairing automatically.
I have been doing a ton of research on this project I want to do, probably read every SO post (bluejacking, RFCOMM, beacons, etc...) and my head is spinning.
I want to create a system at home, using Arduino (with bluetooth le) that will scan bluetooth and detect when my phone or any of my family members phones are in proximity. Whether this is a MAC scanner or simply getting the friendly name. I would also like to get the RSSI. I dont need to do accurate distance measurement but I would like to know approximately how close they are. Does anybody have any suggestions for this approach? I know I can create an app on the phone and have it become a beacon and this may be an option but I am concerned with Android, it would have to be Marshmallow 5.0 at a minimum. I would like support to be a little lower than that, like JB or KK. So, it seems like there should be a simple scan, just looking for the MAC or name. That is all I really need.
That said, the main question I have is, can you scan for and see bluetooth devices in range if they are already paired to something? Like a Bluetooth headset? I understand bluetooth is point to point but does it allow multiple connections or at least broadcast the mac or name when paired?
This question, along with any general suggestions will help me out tremendously!
Thanks!
Bluetooth Discovery from the Listener involves Listening for Bluetooth Inquiry packets(RX) and inquiry response (TX).if done continuously this will deplete the battery. Hence most devices (including Mobile Phones and Headsets) has a policy of when to be discover-able and connectable. Headsets in particular are discoverable only when they are instructed and connectable until one device is connected to it ( There are probably exceptions where the headset has the capability to be connected to multiple phones at the same time). Most Mobile Phones are discoverable only when they are in settings screen ( Android,IOS and Windows Phones), but unlike the headset case they are connectable.
so one option with the MobilePhone is to see if it is possible to connect to them after pairing once ( for example by trying a service search on the remote device and see if it returns the service attributes, this internally makes a connection and indirectly ensures the presence of the device).
if you are specific about a mobile phone which is already paired then you might need to establish a higherlayer connection ( such as SPP) with Authentication and encryption. This would force a two way check between devices to see whether they are already paired. other less secure option is to rely on the Phone (Android and IOS phones doesn't generally Allow a higher layer connection without encryption/pairing) and try to establish an SPP connection to the phone.
Another option is to use Bluetooth-LowEnergy. But Note that security in BT was superior to BLE till BTv4.1 and same on BTv4.2.