doc/connectivity/bluetooth/bluetooth-dev.rst - third_party/github/zephyrproject-rtos/zephyr - Git at Google

 .. _bluetooth-dev:

 Application Development
 #######################

 Bluetooth applications are developed using the common infrastructure and
 approach that is described in the :ref:`application` section of the
 documentation.

 Additional information that is only relevant to Bluetooth applications can be
 found on this page.

 .. contents::
     :local:
     :depth: 2

 Thread safety
 *************

 Calling into the Bluetooth API is intended to be thread safe, unless otherwise
 noted in the documentation of the API function. The effort to ensure that this
 is the case for all API calls is an ongoing one, but the overall goal is
 formally stated in this paragraph. Bug reports and Pull Requests that move the
 subsystem in the direction of such goal are welcome.

 .. _bluetooth-hw-setup:

 Hardware setup
 **************

 This section describes the options you have when building and debugging Bluetooth
 applications with Zephyr. Depending on the hardware that is available to you,
 the requirements you have and the type of development you prefer you may pick
 one or another setup to match your needs.

 There are 3 possible setups:

 #. :ref:`Embedded <bluetooth-hw-setup-embedded>`
 #. :ref:`External controller <bluetooth-hw-setup-external-ll>`

    - :ref:`QEMU host <bluetooth-hw-setup-qemu-host>`
    - :ref:`native_sim host <bluetooth-hw-setup-native-sim-host>`

 #. :ref:`Simulated nRF5x with BabbleSim <bluetooth-hw-setup-bsim>`

 .. _bluetooth-hw-setup-embedded:

 Embedded
 ========

 This setup relies on all software running directly on the embedded platform(s)
 that the application is targeting.
 All the :ref:`bluetooth-configs` and :ref:`bluetooth-build-types` are supported
 but you might need to build Zephyr more than once if you are using a dual-chip
 configuration or if you have multiple cores in your SoC each running a different
 build type (e.g., one running the Host, the other the Controller).

 To start developing using this setup follow the :ref:`Getting Started Guide
 <getting_started>`, choose one (or more if you are using a dual-chip solution)
 boards that support Bluetooth and then :ref:`run the application
 <application_run_board>`).

 There is a way to access the :ref:`HCI <bluetooth-hci>` traffic between the Host
 and Controller, even if there is no physical transport. See :ref:`Embedded HCI
 tracing <bluetooth-embedded-hci-tracing>` for instructions.

 .. _bluetooth-hw-setup-external-ll:

 Host on Linux with an external Controller
 =========================================

 .. note::
    This is currently only available on GNU/Linux

 This setup relies on a "dual-chip" :ref:`configuration <bluetooth-configs>`
 which is comprised of the following devices:

 #. A :ref:`Host-only <bluetooth-build-types>` application running in the
    :ref:`QEMU <application_run_qemu>` emulator or the :ref:`native_sim <native_sim>` native
    port of Zephyr
 #. A Controller, which can be one of the following types:

    * A commercially available Controller
    * A :ref:`Controller-only <bluetooth-build-types>` build of Zephyr
    * A :ref:`Virtual controller <bluetooth_virtual_posix>`

 .. warning::
    Certain external Controllers are either unable to accept the Host to
    Controller flow control parameters that Zephyr sets by default (Qualcomm), or
    do not transmit any data from the Controller to the Host (Realtek). If you
    see a message similar to::

      <wrn> bt_hci_core: opcode 0x0c33 status 0x12

    when booting your sample of choice (make sure you have enabled
    :kconfig:option:`CONFIG_LOG` in your :file:`prj.conf` before running the
    sample), or if there is no data flowing from the Controller to the Host, then
    you need to disable Host to Controller flow control. To do so, set
    ``CONFIG_BT_HCI_ACL_FLOW_CONTROL=n`` in your :file:`prj.conf`.

 .. _bluetooth-hw-setup-qemu-host:

 QEMU
 ----

 You can run the Zephyr Host on the :ref:`QEMU emulator<application_run_qemu>`
 and have it interact with a physical external Bluetooth Controller.

 Refer to :ref:`bluetooth_qemu_native` for full instructions on how to build and
 run an application in this setup.

 .. _bluetooth-hw-setup-native-sim-host:

 native_sim
 ----------

 .. note::
    This is currently only available on GNU/Linux

 The :ref:`native_sim <native_sim>` target builds your Zephyr application
 with the Zephyr kernel, and some minimal HW emulation as a native Linux
 executable.

 This executable is a normal Linux program, which can be debugged and
 instrumented like any other, and it communicates with a physical or virtual
 external Controller. Refer to:

 - :ref:`bluetooth_qemu_native` for the physical controller
 - :ref:`bluetooth_virtual_posix` for the virtual controller

 .. _bluetooth-hw-setup-bsim:

 Simulated nRF5x with BabbleSim
 ==============================

 .. note::
    This is currently only available on GNU/Linux

 The :ref:`nrf52_bsim <nrf52_bsim>` and :ref:`nrf5340bsim <nrf5340bsim>` boards,
 are simulated target boards
 which emulate the necessary peripherals of a nRF52/53 SOC to be able to develop
 and test BLE applications.
 These boards, use:

    * `BabbleSim`_ to simulate the nRF5x modem and the radio environment.
    * The POSIX arch and native simulator to emulate the processor, and run natively on your host.
    * `Models of the nrf5x HW <https://github.com/BabbleSim/ext_NRF_hw_models/>`_

 Just like with the :ref:`native_sim <native_sim>` target, the build result is a normal Linux
 executable.
 You can find more information on how to run simulations with one or several
 devices in either of :ref:`these boards's documentation <nrf52bsim_build_and_run>`.

 With the :ref:`nrf52_bsim <nrf52_bsim>`, typically you do :ref:`Combined builds
 <bluetooth-build-types>`, but it is also possible to build the controller with one of the
 :zephyr:code-sample:`bluetooth_hci_uart` samples in one simulated device, and the host with
 the H4 driver instead of the integrated controller in another simulated device.

 With the :ref:`nrf5340bsim <nrf5340bsim>`, you can build with either, both controller and host
 on its network core, or, with the network core running only the controller, the application
 core running the host and your application, and the HCI transport over IPC.

 Initialization
 **************

 The Bluetooth subsystem is initialized using the :c:func:`bt_enable`
 function. The caller should ensure that function succeeds by checking
 the return code for errors. If a function pointer is passed to
 :c:func:`bt_enable`, the initialization happens asynchronously, and the
 completion is notified through the given function.

 Bluetooth Application Example
 *****************************

 A simple Bluetooth beacon application is shown below. The application
 initializes the Bluetooth Subsystem and enables non-connectable
 advertising, effectively acting as a Bluetooth Low Energy broadcaster.

 .. literalinclude:: ../../../samples/bluetooth/beacon/src/main.c
    :language: c
    :lines: 19-
    :linenos:

 The key APIs employed by the beacon sample are :c:func:`bt_enable`
 that's used to initialize Bluetooth and then :c:func:`bt_le_adv_start`
 that's used to start advertising a specific combination of advertising
 and scan response data.

 More Examples
 *************

 More :zephyr:code-sample-category:`sample Bluetooth applications <bluetooth>` are available in
 ``samples/bluetooth/``.

 .. _BabbleSim: https://babblesim.github.io/
	.. _bluetooth-dev:

	Application Development
	#######################

	Bluetooth applications are developed using the common infrastructure and
	approach that is described in the :ref:`application` section of the
	documentation.

	Additional information that is only relevant to Bluetooth applications can be
	found on this page.

	.. contents::
	:local:
	:depth: 2

	Thread safety
	*************

	Calling into the Bluetooth API is intended to be thread safe, unless otherwise
	noted in the documentation of the API function. The effort to ensure that this
	is the case for all API calls is an ongoing one, but the overall goal is
	formally stated in this paragraph. Bug reports and Pull Requests that move the
	subsystem in the direction of such goal are welcome.

	.. _bluetooth-hw-setup:

	Hardware setup
	**************

	This section describes the options you have when building and debugging Bluetooth
	applications with Zephyr. Depending on the hardware that is available to you,
	the requirements you have and the type of development you prefer you may pick
	one or another setup to match your needs.

	There are 3 possible setups:

	#. :ref:`Embedded <bluetooth-hw-setup-embedded>`
	#. :ref:`External controller <bluetooth-hw-setup-external-ll>`

	- :ref:`QEMU host <bluetooth-hw-setup-qemu-host>`
	- :ref:`native_sim host <bluetooth-hw-setup-native-sim-host>`

	#. :ref:`Simulated nRF5x with BabbleSim <bluetooth-hw-setup-bsim>`

	.. _bluetooth-hw-setup-embedded:

	Embedded
	========

	This setup relies on all software running directly on the embedded platform(s)
	that the application is targeting.
	All the :ref:`bluetooth-configs` and :ref:`bluetooth-build-types` are supported
	but you might need to build Zephyr more than once if you are using a dual-chip
	configuration or if you have multiple cores in your SoC each running a different
	build type (e.g., one running the Host, the other the Controller).

	To start developing using this setup follow the :ref:`Getting Started Guide
	<getting_started>`, choose one (or more if you are using a dual-chip solution)
	boards that support Bluetooth and then :ref:`run the application
	<application_run_board>`).

	There is a way to access the :ref:`HCI <bluetooth-hci>` traffic between the Host
	and Controller, even if there is no physical transport. See :ref:`Embedded HCI
	tracing <bluetooth-embedded-hci-tracing>` for instructions.

	.. _bluetooth-hw-setup-external-ll:

	Host on Linux with an external Controller
	=========================================

	.. note::
	This is currently only available on GNU/Linux

	This setup relies on a "dual-chip" :ref:`configuration <bluetooth-configs>`
	which is comprised of the following devices:

	#. A :ref:`Host-only <bluetooth-build-types>` application running in the
	:ref:`QEMU <application_run_qemu>` emulator or the :ref:`native_sim <native_sim>` native
	port of Zephyr
	#. A Controller, which can be one of the following types:

	* A commercially available Controller
	* A :ref:`Controller-only <bluetooth-build-types>` build of Zephyr
	* A :ref:`Virtual controller <bluetooth_virtual_posix>`

	.. warning::
	Certain external Controllers are either unable to accept the Host to
	Controller flow control parameters that Zephyr sets by default (Qualcomm), or
	do not transmit any data from the Controller to the Host (Realtek). If you
	see a message similar to::

	<wrn> bt_hci_core: opcode 0x0c33 status 0x12

	when booting your sample of choice (make sure you have enabled
	:kconfig:option:`CONFIG_LOG` in your :file:`prj.conf` before running the
	sample), or if there is no data flowing from the Controller to the Host, then
	you need to disable Host to Controller flow control. To do so, set
	``CONFIG_BT_HCI_ACL_FLOW_CONTROL=n`` in your :file:`prj.conf`.

	.. _bluetooth-hw-setup-qemu-host:

	QEMU
	----

	You can run the Zephyr Host on the :ref:`QEMU emulator<application_run_qemu>`
	and have it interact with a physical external Bluetooth Controller.

	Refer to :ref:`bluetooth_qemu_native` for full instructions on how to build and
	run an application in this setup.

	.. _bluetooth-hw-setup-native-sim-host:

	native_sim
	----------

	.. note::
	This is currently only available on GNU/Linux

	The :ref:`native_sim <native_sim>` target builds your Zephyr application
	with the Zephyr kernel, and some minimal HW emulation as a native Linux
	executable.

	This executable is a normal Linux program, which can be debugged and
	instrumented like any other, and it communicates with a physical or virtual
	external Controller. Refer to:

	- :ref:`bluetooth_qemu_native` for the physical controller
	- :ref:`bluetooth_virtual_posix` for the virtual controller

	.. _bluetooth-hw-setup-bsim:

	Simulated nRF5x with BabbleSim
	==============================

	.. note::
	This is currently only available on GNU/Linux

	The :ref:`nrf52_bsim <nrf52_bsim>` and :ref:`nrf5340bsim <nrf5340bsim>` boards,
	are simulated target boards
	which emulate the necessary peripherals of a nRF52/53 SOC to be able to develop
	and test BLE applications.
	These boards, use:

	* `BabbleSim`_ to simulate the nRF5x modem and the radio environment.
	* The POSIX arch and native simulator to emulate the processor, and run natively on your host.
	* `Models of the nrf5x HW <https://github.com/BabbleSim/ext_NRF_hw_models/>`_

	Just like with the :ref:`native_sim <native_sim>` target, the build result is a normal Linux
	executable.
	You can find more information on how to run simulations with one or several
	devices in either of :ref:`these boards's documentation <nrf52bsim_build_and_run>`.

	With the :ref:`nrf52_bsim <nrf52_bsim>`, typically you do :ref:`Combined builds
	<bluetooth-build-types>`, but it is also possible to build the controller with one of the
	:zephyr:code-sample:`bluetooth_hci_uart` samples in one simulated device, and the host with
	the H4 driver instead of the integrated controller in another simulated device.

	With the :ref:`nrf5340bsim <nrf5340bsim>`, you can build with either, both controller and host
	on its network core, or, with the network core running only the controller, the application
	core running the host and your application, and the HCI transport over IPC.

	Initialization
	**************

	The Bluetooth subsystem is initialized using the :c:func:`bt_enable`
	function. The caller should ensure that function succeeds by checking
	the return code for errors. If a function pointer is passed to
	:c:func:`bt_enable`, the initialization happens asynchronously, and the
	completion is notified through the given function.

	Bluetooth Application Example
	*****************************

	A simple Bluetooth beacon application is shown below. The application
	initializes the Bluetooth Subsystem and enables non-connectable
	advertising, effectively acting as a Bluetooth Low Energy broadcaster.

	.. literalinclude:: ../../../samples/bluetooth/beacon/src/main.c
	:language: c
	:lines: 19-
	:linenos:

	The key APIs employed by the beacon sample are :c:func:`bt_enable`
	that's used to initialize Bluetooth and then :c:func:`bt_le_adv_start`
	that's used to start advertising a specific combination of advertising
	and scan response data.

	More Examples
	*************

	More :zephyr:code-sample-category:`sample Bluetooth applications <bluetooth>` are available in
	``samples/bluetooth/``.

	.. _BabbleSim: https://babblesim.github.io/