In short
When I connect to a BLE device with an unofficial app/program, GATT commands are not executed by the device.
Does the app need to run some king of authentication with the device? (a Bulb)
My reverse engineering story
I am trying to reverse-engineer a Bluetooth LE bulb (the Holi Sleep Companion). I have successfully found the GATT messages I need:
by reading the HCI journals from Android (dev tools)
by disassembling the Java code of the Android app (Sleep360)
However, sending the exact same sequence of Bluetooth messages to the Bulb does not work.
While testing, I actually found that the following works for one GATT command if quickly run in the right order:
I connect the official Android app
I close the official Android app
I connect my own app/program and send one GATT command (from the same device or another)
My tests
I run my tests with two methods:
with the nF Connect Android app
with my own python script running on a Linux laptop with bluez
Thank you for you help!
No there is no such "authentication standard". You have the pairing and bonding however in the standard but that is usually taken care of by the system and not by an app in Android.
A manufacturer is free to use GATT as a transport layer and then build an authentication protocol on top of it.
Related
Operating system: MacOS
Just for some context on what I am trying to do, I have an Ikea standing desk which has bluetooth. I am able to control the desk with a built in app. I want to create a server running on a raspberry pi that connects to desk and controls it, I then want to create an Alexa skill which will control the desk by calling the server endpoints.
What's the best language/library you would suggest I use? Ideally something that would run on MacOS and Ubuntu.
I don't know anything about BLE yet which is why it is hard for me to find a good answer. If you have resources, books or tutorials that will help me get running with BLE please recommend them.
My use case:
Get desk to go up
Get desk to go down
Get current position of desk
If you want to write one app that works for both MacOS and Ubuntu then as ukBaz said, python and Bleak are your best options. If you want to use the native way of writing BLE apps for each OS, then you can use CoreBluetooth on MacOS and BlueZ on Ubuntu. The advantage of the former is that you can get an application up and running quickly, and the advantage of the latter is that you will find a lot more resources and advanced functionality.
Below are some resources that can help you in your development:-
Theoretical Bluetooth:
Bluetooth Low Energy: A Primer
Getting Started with Bluetooth Low Energy
Ellisys Bluetooth Series
CoreBluetooth
Getting Started with CoreBluetooth
Ultimate Guide to Apple's CoreBluetooth
iOS App Full Example
BlueZ
Configuring Bluetooth devices with bluetoothctl
Ubuntu: Accessing GATT services
Python
Ikea IDÅSEN desk API and CLI
Idasen controller example
Using Python for Bluetooth
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
I am using MIT App Inventor 2 to do some bluetooth connection. I am trying to connect to my Arduino Bluetooth hc05.
I noticed that if I didn't pair my device, the app I wrote can't connect to the device.
Below is the code that I used to connect to my Bluetooth device.
Is there any way to use the code to connect with the Bluetooth device without having to pair it first?
Or is there any way to use the code to input the pairing password using MIT App Inventor 2?
The devices must be paired before being able to connect.
There is no Pairing method available in the App Inventor Bluetooth components. But you could write your own extension, which does the pairing.
More information about how to create an extension see here.
However that will be more advanced and will require some Java skills...
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
I need to make an app in J2ME that can be able to read a SMS and then print it on an epson tm-p60 printer(ESC/POS emulation) via bluetooth.
i looked at the epson supprt site but the only ADK/drivers they provide are for:
1.Sun Java2 SDK Standard Edition Version 1.4.2_10
2.Sun Java2 SDK Standard Edition Version 1.4.2_04
3.Sun Java SE Development Kit 6 Update 3
so i don't know how am i gonna be able to use ESC/POS commands inJ2ME.
I'm a bit clueless on how i will approach this project.. plus w/c would be better to use for this project? Netbeans or Eclipse?
Thanks!
SPP (Serial Port Profile) over Bluetooth means using an RFCOMM connection to send and receive data as if it were a physical serial connection. This is part of JSR 82, so you will be able to develop only on handsets that support this JSR.
You need to:
Figure out how to discover bluetooth devices, and scan for SPP services on a discovered device, then connect to one of those services, using one of the many JSR 82 tutorials out there.
Then send ESC/POS protocol data over that connection -- I assume you have the protocol specification available? Google turned up this application programming guide.
HTH.
JSR-82 Bluetooth API support L2CAP protocol, RFCOMM and OBEX profile. I don't know detail of Bluetooth basic printing profile (BPP) but, if you look into basic printing profile document you can find that BPP built on OBEX profile.
I can't find open source project for BPP on JSR-82. Please try to search it, but if you can't find one you might need to write your own.