I am trying to develop a bluetooth LE peripheral in intel-edison, by using C library. The device should be able to :
advertise (GAP)
accept connection (GAP)
support custom GATT service, simply read/write value of characteristic.
I try to use HCI and bluez to implement this. bluez-experiments, intel-edison-playground, which demonstrate how to advertise and scan, can be compiled and run on edison. BLE advertising and scanning do work.
But I have hard time to figure out how to accept connection and support GATT service. I try to search on goolge about the HCI document but have no luck. Can someone provide a snippet of code (c or pseudo or a description)?
Thank you so much!
Andrew
If you download the bluez source you'll find documentation on the hci protocol in /doc/mgmt-api.txt. I'm not using the hci interface myself, and I'm not sure if the developers intend for implementors to use this interface to implement peripherals, so I'm not sure how well this will work.
I went with the DBus API approach for my project, which is outlined in /doc/gatt-api.txt and /doc/advertising-api.txt. This approach involves writing a program which creates DBus objects which support specific org.bluez DBus interfaces (GattService1 which contains GattCharacteristic1 and GattDescriptor1) and the ObjectManager interface to expose everything to bluez. You then use LEAdvertisment1 to define what is advertised and register the advertisement using the LEAdvertisingManger1 interface on the adapter.
I used Qt to simplify the DBus communication parts.
The DBus API for BLE on bluez is still in heavy development, and not all features are supported (I still haven't found a way to start and stop advertising, for example). 5.31 contains a lot of added supported and some critical bug fixes for descriptors, but requires a newer kernel.
Related
I would like to use the PJSIP library to implement a small SIP softphone on an embedded system. Since this embedded system does not offer Linux or support POSIX, I would like to port the PJLIB library only partially, as described here (https://www.pjsip.org/porting.htm#mozTocId30930). The threading function can be deactivated via a macro, but I'm not quite sure yet how I have to set up this new transport function or where exactly it has to be included so that I can also bypass the IOQUEUE implementation and the PJLIB socket abstraction.
On my embedded system (Keil RTX) I can allocate a UDP socket and register a callback which is called on a network event. I also have a send function which I can use to send data packets. Although I have already looked into the stack, I can't find a way to get started.
Has anyone already dared to the partial porting and can give me a brief assistance. Thank you !
See how Symbian port worked (I think it might be removed from recent versions, but it should be still downloadable) - it was also based on non-POSIX sockets. Create your own platform-specific socket file and ioqueue file.
I did not find more than one normal of the described example for connecting and working the VL53L0X with the STM32 microcontroller. All examples are tied to using the library from ST to work with VL53L0X. Is there any way to work with VL53L0X without using any libraries? Just send an inquiry via I2C and receive a response. Maybe someone faced such a problem and found a solution?
If it is necessary to use the library to work with VL53L0X, then someone can explain in detail how to use it on any microcontroller from ST, and not just with P-NUCLEO-53L0A1 as in the example from ST. In all my programs I use exclusively CMSIS, and not when I didn’t work with HAL libraries, so I don’t know how to connect this library?
Visit https://github.com/yetifrisstlama/vl53l0x-non-arduino
It is a lightweight VL53L0X API which does not use any HAL-Lib. You can easily implement it into your project.
Currently I am working on a Version of this API, including some HAL references for a better i2c communication. Maybe I will leave it here later when done.
I will need the ability to communicate with a device attached via USB that shows up as a serial port. Is this possible with cn1? I haven't seen any reference to it. Does the native java import javax.comm.*; work on all platforms?
No, comm isn't portable. You would be able to bundle it into the desktop port but you'd need a different implementation for everything else using the native interfaces.
Before we had builtin support for sockets Steve created a cn1lib for socket support which you can use as a reference to how one would implement streaming data over native interfaces
I want to establish Bluetooth network where one server can communicate to two clients (ie piconet) using C programm on linux platform, rfcomm based communication.
Can any one please share your guidance or sample source code if have.
I newbie to the bluetooth technology, have not found any useful info or code from internet source so far. so please.
Thank you
Basu
Linux runs open source BlueZ Bluetooth Stack, which works quite well (unless you need Bluetooth Low Energy). You can check out this tutorial: http://people.csail.mit.edu/albert/bluez-intro/c404.html
PS. Mind the GPL license when using #include like in those examples.
Edit:
As for creating piconet specifically, I'm afraid I don't have any snippets. However, after quick search, I would look into using bluez library to open not one but many RFCOMM sockets. So you can listen to and accept multiple connections.
I have a dsPIC33 with ECAN and wish to establish a protocol (using SDO if possible) in such way that it communicate between terminal software and dsPIC33 where I can perform diagnostics within dsPIC33 and supporting ICs.
I do not know what is required, so what is a low cost way of doing this? I could use a CAN-to-USB device, but I am unsure if this will work. What kind of protocol inside CANUSB wraps around the ASCII-based message?
What hardware can I use? Can it be used to monitor the CAN bus as well? I do not wish to invest in an expensive setup as in Vector or similar heavy-weight solution.
When you purchase CAN interface hardware, it does not typically include software to work with specific upper-level CAN protocols (like CANopen). They do usually come with a set of DLL files that allow you to write custom PC applications to interface with your hardware.
If you do not want to purchase any third-party software, then you must:
Implement a basic CAN driver for the dsPIC33 (transmit and receive a basic frame).
Implement the CANopen SDO protocol on top of your basic driver on the dsPIC33.
Purchase a low-cost CAN<->USB interface (which should come with DLLs that allow you to develop in C, C++ or C#.
Write a PC application using the DLL files which implements the CANopen SDO protocol.
You may want to look for open-source implementations of the protocol. One such implementation is CanFestival. However, I have never used this library.
You can download an open source project for CANopen from DATALINK ENGINEERING as this seems to be just what you need.