Bluetooth Low Energy:Android Gatt-Client Connect to Linux Gatt Server

Bluetooth Low Energy in C - using Bluez to create a GATT server

I got the example GATT server running for BlueZ 5.31 (latest as of this post):

My environment:

Vagrant

Virtual Box

Ubuntu Trusty Tahr as a guest OS (v. 14.04 32-bit OS)

Updated to linux kernel 3.19

Installed packages:

* libglib2.0-dev

* libdbus-1-dev

* libudev-dev

* libical-dev

* libreadline-dev

Downloaded BlueZ 5.31 from here: https://www.kernel.org/pub/linux/bluetooth/bluez-5.31.tar.xz

Installation of updated kernel (v. 3.19):

sudo apt-get update

sudo apt-get install --install-recommends linux-generic-lts-vivid

A reboot is necessary. I'm using Vagrant and lost shared folder access. If this happens to you, wait for vagrant to report the error and go into the VM anyway (vagrant ssh). In the VM, issue this command to fix the shared folder problem:

sudo /etc/init.d/vboxadd setup

I would reboot again (probably not necessary), to check that the shared folder is active again.

Once back in the VM, continue the installation of BlueZ 5.31:

cd ~

sudo apt-get install libglib2.0-dev libdbus-1-dev libudev-dev libical-dev libreadline-dev

wget https://www.kernel.org/pub/linux/bluetooth/bluez-5.31.tar.xz

tar xvf bluez-5.31.tar.xz

cd bluez-5.31

./configure --prefix=/usr --mandir=/usr/share/man --sysconfdir=/etc --localstatedir=/var --disable-systemd --enable-experimental --enable-maintainer-mode

make

sudo make install

sudo cp attrib/gatttool /usr/bin

Installation completed. Check it as follows:

hciconfig
You should get the follow response (or something similar):

hci0: Type: BR/EDR Bus: USB

BD Address: 00:1A:7D:DA:71:0C ACL MTU: 310:10 SCO MTU: 64:8

DOWN

RX bytes:15528 acl:126 sco:0 events:683 errors:0

TX bytes:6459 acl:146 sco:0 commands:234 errors:0

Configure the Bluetooth adapter, start advertising, start example GATT server (heart rate service) with verbose on (my adapter is hci0):

cd BlueZ 5.31 directory
sudo tools/btmgmt -i hci0 power off

sudo tools/btmgmt -i hci0 le on

sudo tools/btmgmt -i hci0 connectable on

sudo tools/btmgmt -i hci0 name "some friendly name"

sudo tools/btmgmt -i hci0 advertising on

sudo tools/btmgmt -i hci0 power on

tools/btgatt-server -i hci0 -s low -t public -r -v

Go to another device (I've used an iPod, an Android -- Samsung Galaxy 5S and Nexus tablet -- and another PC running BlueZ) and connect to the service. Here is how I did it on another PC running BlueZ:

gatttool -b MAC address of GATT server -I

connect

primary

characteristics

You can issue other commands to read and write to the GATT server.

I've also created a custom GATT server (your original request) by copying and editing this file: tools/btgatt-server.c. You can edit the Makefile.tools file to include your custom server in the build. You'll have to run automake, make, and sudo make install to get it running.

Python BLE GATT Server personalised characteristic read

ReadValue and WriteValue have an options parameter that contains the connected device path, and this will identify it.

  def WriteValue(self, value, options):

    if ("device" in options):
      print(options['device'])

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