I have a BLE thermometer and I'd like to record the data from it as the monitoring application (available for both Android and iOS) that comes with it doesn't do it, it merely displays the data on the screen for a limited time.
I tried all BLE apps on both Android (I have a Nexus5 with Android 4.4) and iOS 7.1 iPad with but, while some discovered the device, none of them could display any data because all try to connect to the sensor whereas the sensor returns 0 for kCBAdvDataIsConnectable.
Is this possible? It must be because its own app does it, but I'm not too familiar with BLE and I may be missing something. I was surprised that none of the apps in the App/Play store had the feature of "listening" what a device sends without connecting. But then again, I'm not very familiar with BLE.
A few pointers are appreciated.
Related
I'm trying to establish a connection between my PC running Ubuntu and my iPhone via Bluetooth automatically when it becomes available, after being manually paired beforehand. I've seen this to be possible with certain peripherals, mainly audio. For example, my phone will automatically connect to a Bluetooth speaker when it is turned on and Bluetooth is active on my phone; another example is my phone automatically connects to my car's radio system via Bluetooth when I turn the car on.
I'm not able to connect my phone to my PC without first initiating the connection from the smartphone's Bluetooth menu. I'm thinking that I could possibly write an application for the PC to attempt to connect to the device every few minutes or something, but it seems that the phone needs to be the device to initiate the connection.
The only information that I need for what I'm trying to do ultimately is that the devices can pair successfully. Essentially I'm trying to build a sort of proximity trigger between my phone and my PC without using Wi-Fi and GPS - I can't use these for some specific reasons.
Is there any way to make this happen?
Yes this should be doable as long as you use the Background Processing feature for iOS apps. In the example I'll give below, we'll have the PC be the peripheral and the phone be the central, but you can really have it working either way. You will need to do the following:-
First initial connection needs to be performed in the foreground (this is due to iOS's background limitations).
On the iOS side, you need an application that acts as a central that scans and connects to the remove device (check this example as a starting point).
Upon connection, you need to bond with the PC. Bonding is important as it will prevent you from having to do the pairing again in the future. However, pairing/bonding is managed by the iPhone's OS so you cannot write it in your application, so the workaround is to have an encrypted characteristic on the PC side that will force the iPhone to bond (this is covered later).
On the PC side, you need to have a BlueZ script that acts as a peripheral that is always advertising. You can do this using bluetoothctl (check the examples here and here).
Before you start advertising, you need to have a GATT server on the PC side (to do this, check this example).
When registering characteristics, ensure that one of them has the encrypt-read property (you can find a full list of the properties here).
Now when you attempt to read this characteristic from the iOS side, the two devices should bond (make sure that your PC is bondable which you can do this via these commands).
Once the devices are paired, your iOS app needs to be working in the background constantly scanning and attempting to connect to the same peripheral (have a look at this and this example).
You can find more useful information at the links below:-
Getting started with Bluetooth Low Energy
The Ultimate Guide to CoreBluetooth Development
How to manage Bluetooth devices on Linux using bluetoothctl
When performing a BLE scan using startScan(onFoundBLEDevice, onBLEScanError). First, is the parameter sent to onFoundBLEDevice a single device or is it a list of devices? And if the answer is "single device" what happens when there is more than one BLE device in the local vicinity when performing the scan?
Secondly, Since my goal is to retrieve the battery level from my own smartphone (the one that is paired AND connected to my smartwatch) how can I tell which of the devices found by my scan is the one that's connected? Or do I even need to perform a scan? Is there another way to retrieve the device object in order to then get the battery service 0x180F and then the battery level characteristic, 0x2a19? In other words, I want to be sure that the battery level I retrieve is that of my phone, not my buddies sitting next to me.
UPDATE: my smartphone is a Samsung Galaxy S3 running Android 4.3 and my smartwatch is a Samsung Gear S2 running Tizen 2.3.1. I'm using Tizen Bluetooth API.
The BluetoothLEScanCallback (In your case onFoundBLEDevice) is invoked everytime a device is found. (For 3 nearby devices -> 3 calls)
I've scanned nearby devices from my gear while it's connected with a Mobile through 'Samsung Gear' app. No, There's no way to distinguish specific Mobile connected via Gear Manager from other devices. So, You can't find the connected device in this procedure. (Unless you are developing the app for personal use, In that case you can hardcode your Mobile device's UUID)
Samsung Provides 'Accessory' SDK for such purposes.
Samsung Accessory SDK
Any data you exchange using Accessory SDK would provide you info of specific 'The Connected' device via Samsung Gear. Check Out the API References, Programming Guides and Android-End Sample apps and Tizen-End Sample apps in Accessory SDK section.
I am developing an app that controls a product's operation. The communication is via BLE. My configuration is
App - Peripheral (iOS, Android)
Product - Central (uses Laird BT900 module)
iOS as a peripheral works fine (pairing and bonding) ; Android PIN pairing works fine, but subsequent bonding (or reconnect when in range) there are a lot of issues and termination of connection. I am using the supported list of devices for Android BLE and I also understand that there are many known issues that come with different manufacturers/chipset vendors
The issue I am getting is, as seen by nrfConnect, is with descriptors. Android app doesnt show descriptors when seen in nrfConnect whereas iOS shows. I do not know what is the difference
Is it a common practice to use a phone as a peripheral ? Or is it a risk - because this is a medical device.
Are there any best practices for Android as a peripheral ?
I have following back up plans in case Android issue is not resolved. I think following would work on any BLE supported phones without having any issues with the variability.
Plan A : PIN pairing on every connection with the product. This is the most secure and most annoying
Plan B : Implement just works pairing with a app layer password before taking control of the product.
Question : Is just works safe and encrypted ? Is it snoop-safe or MITM-safe ?
Thanks in advance!
A few thoughts from your questions:
1a. (From my Android experience) I think its uncommon to have the phone be the peripheral. To my knowledge all iOS devices support peripheral mode but only a very small subset of Android devices are able to support it. I say this because I've been experimenting with BTLE beacons using the AltBeacon library. From this work I have discovered that only certain Android phones can broadcast BTLE advertise packets. Given that BTLE advertising is the first step in initiating a BTLE session I imagine that this prevents many Android phones from being compatible with peripheral mode.
If all of your users can use an iOS device, then you're set, otherwise this may be a problem.
1b) I can't speak to the specific risk of using a mobile device with your medical device, that depends on what the medical device is doing and how you're using the mobile app.
2) See 1a
3) The specific encryption scheme you used is also based on your product's risk profile. I would say that Just Works is not an ideal solution. The just works pairing process is not snoop-safe and can be re-initiated via a MITM. Other than that I can't speak to the strength of BTLE encryption.
I have a WPF desktop application that would make a good candidate as a Universal Windows App. The application has a must-have dependence on USB or Bluetooth devices that act as a Serial Port.
In all my reading I've yet to discover whether there is any access to a SerialPort API in a UWA.
I suspect the answer is 'No support'. If so, does anyone know of a USB or Bluetooth GPS that supports whatever APIs the UWA has for that sort of thing. I have to be able to read things like ground speed, elevation, rate of climb, etc.
If the answer is 'Supported', could you point me to some documentation.
For the "Bluetooth devices that act as a Serial Port", I assume you mean the RFCOMM. They are both supported on Windows Runtime since Windows 8.1 and you can also use them in the Universal Windows Application.
namespace: Windows.Devices.Usb and Windows.Devices.Bluetooth.Rfcomm.
About the Bluetooth GPS, I'm not sure if it uses RFCOMM or not (it depends on the devices), and it is also possible to use the GATT.
Code Sample: Custom USB device access sample
I want to know if the developer team which made the emulator have some information to make bluetooth work in the Android emulator, indicate some links about it, if they have some date for release or if they'll make it works in the future.
as far as I know there is no support in the emulator for bluetooth. And I will have to teach android and bluetooth in some classes. And the students will need to code stuff and test (guess it) in the android emulator.
So I came up with a bare-bone reimplementation of the android bluetooth API on top of tcp. You can find it on here on github.
Basically, you run a tcp-server on your machine, and the emulators will connect through it.
Instead of using the classes in the package android.bluetooth, you just need to use the classes in the package dk.itu.android.bluetooth (and other 2 little modifies).
As for now it supports:
switch on/off the "radio"
discovery devices (only other android emulators)
creating bluetooth services
connecting to bluetooth services
It's not much, but until we got some more from the android guys, I guess there is nothing else around.
Hope it'll be useful, cheers!
The documented bluetooth limitation appears inconsistent with the qemu -bt option. So, how is bluetooth enabled in the emulator so the -bt options can be used, or at least to know that bluetooth is supported?
The target/board/.../BoardConfig.mk having "BOARD_HAVE_BLUETOOTH := true" doesn't provide a bluetooth icon or enable bluetooth. So, how do we turn on bluetooth on the android qemu emulator?
What does it mean that bluetooth is not supported given the -bt option for emulating USB devices that were provided in 2008? The post and limitations are outdated.
The functional limitations of the emulator include:
No support for placing or receiving actual phone calls. You can simulate phone calls (placed and received) through the emulator console, however.
No support for USB connections
No support for device-attached headphones
No support for determining network connected state
No support for determining battery charge level and AC charging state
No support for determining SD card insert/eject
No support for Bluetooth
http://developer.android.com/tools/devices/emulator.html#limitations