I'm trying to setup a bluetooth server for one device with Qt and can't figure out how to use QDbus and bluez.
The device is going to send strings. The two are already paired.
Your question is quite generic, what is your problem exactly?
A very good resource to start understanding bluetooth protocol and its programming model in C is http://www.btessentials.com/
The original resource that has reorganised into the mentioned book is available online here Once you will have a fair understanding of the basic you could seriously think to wrap everything with Qt :)
Related
I want to create a TAS that can play the Nintendo Switch games that are only compatible with the joy cons.
There are turbo pro controllers in the market but there is no turbo joy cons, so my next idea is one of two:
To use the Bluetooth to connect a devise that I could control with my PC and can be connected to the Nintendo switch via Bluetooth (or USB) and trick it into thinking that it is a joy con and not a pro controller.
Use the idea above but the devise is the joy con itself, in this case, I would have to connect the joy cont to the PC and command it while it is still paired with the Nintendo Switch
Is there any way to achieve what i'm looking for? Thanks in advise.
Also, if there is a better branch in stack-overflow to post this question I will move it.
Looks like it's already been done, and you'll need a product called vJoy.
https://www.pcgamesn.com/nintendo/nintendo-switch-joy-con-pc-guide
Looks like you'd need to reverse engineer the communication protocol used by those controllers and then emulate that protocol with software. Here is a resource I have found regarding RE bluetooth. Another one I have found here. Redfang may help you in that endeavor, it is software that helps you find bluetooth addresses of devices that you you can't discover normally.
Another idea I would have is to open your controller and solder on some wires to a micro controller, such as an Arduino, Raspberry or something similar to the buttons and analogue controllers and 'input' the commands that way.
Unfortunately I can not offer you any more advice. I hope this helps in some way.
One possible way is to use JoyCon Droid app in Android to controll the Nintendo Switch. If this app can work, it should be possible to make one as PC software too.
Luckily, there are a few easy ways to control Android from PC such as using AirDroid which allows you to touch the Android screen from PC. You can refer to How to remote control Android device from a computer with AirDroid?. It can both mirror the screen and give you the touchscreen control, which you can utilize it to control the JoyCon Droid app.
I've just found another way which is to use a microcontroller as a USB controller here.
I want to use a bluetoothmodul like this Waveshare Core51822 to send data to a raspberry. I want to use the SPI on the bluetooth modul but i dont have a plan how to configure that.
What do i need?
Thanks
The SPI and BLE are all documented extensively at http://infocenter.nordicsemi.com/, including examples, specifications, and an API.
In the future, you should give much more information about your situation. For instance, what platform/IDE are you using to develop? If your module is compatible, you would probably be best off using ARM's mbed compiler (https://os.mbed.com).
I have a device with a few custom GATT services, and I would like to write a Linux program to interact with it. After some searching I found out that Linux is using BlueZ to handle the Bluetooth LE protocol. I'm using Ubuntu 15.10 with BlueZ 5.35, but I cannot figure out how use this BlueZ from a user-space program. I cannot find an API documentation anywhere, no tutorials, examples, nothing. Is it even possible to use this BlueZ stack to do anything other than just connecting to Bluetooth devices with default services? And if so, where is the documentation? (Preferably C/C++ API but at this point anything goes)
Have a look at attrib/gatttool.c in the bluez sources [1]. Gatttool is a command line utility for connecting to BTLE devices using the C "API". The GATT interface is not exposed in libbluetooth though.
A newer alternative to gatttool and thus another example to learn
from is the btgatt-client, which you can find in
tools/btgatt-client.c (to enable compilation configure bluez with
--enable-experimental).
Besides the C interface bluez integrated a DBUS interface.
bluetoothctl is an example tool using the DBUS interface. The code of
bluetoothctl can be found in client/ [2].
Another example program using the C interface of bluez is the Anki
Drive SDK [3]. It packaged the bluez GATT C interface in its own
library libbzle [4]. When using the C interface you have to connect a
socket when establishing a BTLE connection. The gatttool does this
via the GATT interface, which in turn uses glib iirc. But you can
also do this using syscalls (socket, connect, ...) as explained e.g.
here [5]. This document also explains:
Unfortunately, as of now there is no official API reference to refer to, so more curious readers are advised to download and examine the BlueZ source code.
Gilbert Brault also extracted the GATT interface from bluez [6] and links to a rudimentary doxygen documentation of the GATT interface [7] with the following disclaimer:
This is a work in progress with the intent of documenting all important functions and data structures
Also Szymon Janc gave a nice overview in his talk "Bluetooth on Modern Linux" at the Embedded Linux Conference 2016 [8]. Starting at 42:00 he talks about the unexposed C interface. But in general he seems to recommend the DBUS API (see "Tips" slide at 45:30). Some DBUS documentation can be found in doc/gatt-api.txt [9] and Python examples using the DBUS interface can be found in test/.
Hope this helps.
[1] http://git.kernel.org/cgit/bluetooth/bluez.git/tree/attrib/gatttool.c
[2] http://git.kernel.org/cgit/bluetooth/bluez.git/tree/client/
[3] https://github.com/anki/drive-sdk/
[4] https://github.com/anki/drive-sdk/tree/master/deps/bzle/
[5] https://people.csail.mit.edu/albert/bluez-intro/c404.html
[6] https://github.com/gbrault/gattclient
[7] http://gbrault.github.io/gattclient/index.html
[8] https://www.youtube.com/watch?v=tclS9arLFzk
[9] http://git.kernel.org/cgit/bluetooth/bluez.git/tree/doc/gatt-api.txt
I feel your pain. I needed to add user input from a custom BLE peripheral, a simple remote pushbutton, to an embedded program running under Linux (Stretch) on a Raspberry Pi. I was stunned by the needless complexity and Spartan (not a compliment) documentation of the BlueZ API. All the BlueZ “examples” are written from the perspective that Bluetooth is the center of the universe and the user wants to support every Bluetooth device ever invented. In my case I knew exactly the device, service, and GATT characteristics I needed to interact with, and I wanted a minimum overhead task that would do its thing in a low priority thread.
It turns out a BLE central client is pretty straightforward using BlueZ, but it was an arduous road starting with the source for the BlueZ utility bluetoothctl in release 5.49. I accomplished my needs using only three unmodified source files from the BlueZ distribution and excerpts from an additional three source files. Since the BlueZ source is inextricably dependent on D-Bus and the Gnome GLib main loop, I grudgingly included them.
Following OlivierM's generous lead, and in hopes that my embarrassingly massive investment in time saves someone else a month of their life, I have posted my example Bluetooth BLE client on GitHub: https://github.com/jjjsmit/BluetoothBLEClient
It would arguably be simpler and quicker to write a shell script on Linux to do what you need to do. The BlueZ commands are relatively simple and straightforward, and there are many tutorials and questions on how to use it.
Tutorials:-
http://www.jaredwolff.com/blog/get-started-with-bluetooth-low-energy/
https://learn.adafruit.com/reverse-engineering-a-bluetooth-low-energy-light-bulb/control-with-bluez
https://lilyhack.wordpress.com/2014/02/03/ble-read-write-arduino-raspberry-pi/
http://joost.damad.be/2013/08/experiments-with-bluetooth-low-energy.html
Questions:-
Using Bluetooth low energy in linux command line
Bluetooth Low Energy: listening for notifications/indications in linux
How can I connect to the FitBit Zip over Bluetooth 4.0 LE on Linux with bluez?
Once you are more familiar with using the commands manually you can then write a minimal shell script so that this is automated for you.
I had a similar issue which is to interact with a BLE device with a GATT C/C++ API. I have realized there was no such API existing.
The way I fixed my issue was to write my own GATT library. I have pushed the code on Github: https://github.com/labapart/gattlib
I use this library in my own BLE project and it fulfils my needs. I created few examples https://github.com/labapart/gattlib/tree/master/examples that use the library to encourage people to use it and have better feedback.
I recently found out that Qt has Bluetooth Low Energy support as host since Qt 5.7. Qt Bluetooth LE. It is available under LGPLv3 or commercial license, and exposes a C++ API.
I have recently purchased an RFID reader that uses RS232 communication. What I want to do is essentially to use this reader on my Raspberry Pi(which does not use x86 architecture). However the seller only sent me SDKs that uses .DLL for C#, Visual C, Delphi and even for Java SDKs!
I tried looking for generic SDKs online but couldn't really find any.
My question is is there any way to convert these into Linux compatible that would work with any other architecture?
Since the Raspberry Pi uses an ARM architecture you are most likely out of luck as the DLL SDK is probably x86 architecture only.
But don't give up hope. You still have more options:
You may be able to use a Minnowboard and get x86 Linux with Wine running under it and make use of the DLLs that way. I believe the Wine COM port code is pretty stable.
If it is truly an RS-232 you should be able to hook the reader up to the serial port of a Raspberry Pi, set your com settings ('baud', stop bits, parity, handshake) with stty and read the output of the reader in Linux. It should be a simple dump of the RFID interrogations.
You may need to do a little bit of protocol reverse engineering, but for a RFID reader this should be pretty easy (about as easy as it gets). If you need to, you might be able to dig up some stuff on-line or ask the manufacturer for the device communication protocol specs.
Here's a link to a serial library for the Raspberry Pi in straight C that should get you going.
Is it possible to make a computer behave as a bluetooth HID device? That is, given a local machine with a standard USB keyboard plugged into it, other devices could discover this machine and use it as a bluetooth keyboard.
I'd like to create a linux or OS X application (or use an existing one, though I've found none) which can behave as described above, but I'm not sure where to start, or if it's even possible.
So:
Is what I'm describing possible?
Are there any existing applications that do what I describe?
If no application already exists (I'm assuming not), are there bluetooth libraries or bindings that will help? (I'm pretty comfortable using most of today's popular languages, so I'd prefer a library most directly suited to the task, so long as it's available in linux or OS X.)
Failing any of the above, the bluetooth spec looks pretty dense. Are there specific guides or other starting points applicable to the problem at hand that I can read?
I realize that such an application would most likely need to steal the normal keyboard input, possibly providing some KVM-like hotkey for switching between providing input to the host operating system and sending the input over bluetooth to the connected device, but I'm considering that problem to be outside the scope of this question.
It is definitely possible on Linux. Some time ago I found this project:
http://nohands.sourceforge.net/index.html
They emulate a full-blown headset with audio and keyboard controls on the Linux bluetooth stack. If they can emulate something like that, you would probably be able to emulate something simpler like a keyboard.
It is possible, however I don't think I'll be able explain it very well and I don't know the entire answer. A BT HID device works as a server and waits for connections to come to it. In linux, using the bluez stack, first you would have to advertise the HID service for other devices to see. I think you do that using the sdp.h and sdp-lib.h header files(the second header maybe called something else, I'm on a windows computer and can't check). So you would have to add the HID service record to you computer for other devices to see it. You would have to create a program that first adds this service to the record, then waits for other devices to connect, then handle the pairing process, Bluez might handle this for you, or you might have to do some things to it, I'm not quite sure. You should also read the Bluetooth HID Spec found at the http://www.bluetooth.com/English/Technology/Building/Pages/Specification.aspx site. This document contains the details of the SDP record relevant to HID. Also the book Bluetooth essentials for programmers is pretty good to introduce you into bluetooth programming
I would like to have given a more concise answer, with more detail, but that's all I know ATM. I am also trying do something similar, but spare time is so hard to find ;) I'm also not on my Linux box and can't check all the details. If your are still interested, let me know and i'll try to expand my answer.
I don't know if this is helpful, nor if it is still alive and working, but perhaps you could try this link.
Another one that might or might not be helpful in some way is remuco, but I don't know if they are using a Bluetooth HID profile.
It is indeed entirely possible with Linux and Bluez. See: https://github.com/lkundrak/virtkbd/blob/master/btkbdd.pod
Try Across, unfortuantly for me my phone was lacking support.