Matter nRF Connect Lock Example Application#
The nRF Connect Lock Example demonstrates how to remotely control a door lock device with one basic bolt. It uses buttons to test changing the lock and device states and LEDs to show the state of these changes. You can use this example as a reference for creating your own application.
The example is based on Matter and Nordic Semiconductor’s nRF Connect SDK, and was created to facilitate testing and certification of a Matter device communicating over a low-power, 802.15.4 Thread network, or Wi-Fi network.
The example behaves as a Matter accessory, that is a device that can be paired into an existing Matter network and can be controlled by this network. In the case of Thread, this device works as a Thread Sleepy End Device. Support for both Thread and Wi-Fi is mutually exclusive and depends on the hardware platform, so only one protocol can be supported for a specific lock device.
Overview#
This example is running on the nRF Connect platform, which is based on Nordic Semiconductor’s nRF Connect SDK and Zephyr RTOS. Visit Matter’s nRF Connect platform overview to read more about the platform structure and dependencies.
By default, the Matter accessory device has IPv6 networking disabled. You must pair it with the Matter controller over Bluetooth® LE to get the configuration from the controller to use the device within a Thread or Wi-Fi network. You have to make the device discoverable manually (for security reasons). See Bluetooth LE advertising to learn how to do this. The controller must get the commissioning information from the Matter accessory device and provision the device into the network.
The sample uses buttons for changing the lock and device states, and LEDs to show the state of these changes. You can test it in the following ways:
Standalone, using a single DK that runs the door lock application.
Remotely over the Thread or the Wi-Fi protocol, which in either case requires more devices, including a Matter controller that you can configure either on a PC or a mobile device.
Bluetooth LE advertising#
In this example, to commission the device onto a Matter network, it must be discoverable over Bluetooth LE. For security reasons, you must start Bluetooth LE advertising manually after powering up the device by pressing:
On nRF52840 DK, nRF5340 DK, and nRF21540 DK: Button 4.
On nRF7002 DK: Button 2.
Bluetooth LE rendezvous#
In this example, the commissioning procedure is done over Bluetooth LE between a Matter device and the Matter controller, where the controller has the commissioner role.
To start the rendezvous, the controller must get the commissioning information from the Matter device. The data payload is encoded within a QR code, printed to the UART console, and shared using an NFC tag. The emulation of the NFC tag emulation starts automatically when Bluetooth LE advertising is started and stays enabled until Bluetooth LE advertising timeout expires.
Thread or Wi-Fi provisioning#
The provisioning operation, which is the Last part of the rendezvous procedure, involves sending the Thread or Wi-Fi network credentials from the Matter controller to the Matter device. As a result, the device joins the Thread or Wi-Fi network and can communicate with other devices in the network.
Device Firmware Upgrade#
The example supports over-the-air (OTA) device firmware upgrade (DFU) using one of the two available methods:
Matter OTA update that is mandatory for Matter-compliant devices and enabled by default
Simple Management Protocol over Bluetooth LE, an optional proprietary method that can be enabled to work alongside the default Matter OTA update. Note that this protocol is not a part of the Matter specification.
For both methods, the MCUboot bootloader solution is used to replace the old firmware image with the new one.
Matter Over-the-Air Update#
The Matter over-the-air update distinguishes two types of nodes: OTA Provider and OTA Requestor.
An OTA Provider is a node that hosts a new firmware image and is able to respond on an OTA Requestor’s queries regarding availability of new firmware images or requests to start sending the update packages.
An OTA Requestor is a node that wants to download a new firmware image and sends requests to an OTA Provider to start the update process.
Simple Management Protocol#
Simple Management Protocol (SMP) is a basic transfer encoding that is used for device management purposes, including application image management. SMP supports using different transports, such as Bluetooth LE, UDP, or serial USB/UART.
In this example, the Matter device runs the SMP Server to download the application update image using the Bluetooth LE transport.
See the Building with Device Firmware Upgrade support section to learn how to enable SMP and use it for the DFU purpose in this example.
Bootloader#
MCUboot is a secure bootloader used for swapping firmware images of different versions and generating proper build output files that can be used in the device firmware upgrade process.
The bootloader solution requires an area of flash memory to swap application images during the firmware upgrade. Nordic Semiconductor devices use an external memory chip for this purpose. The memory chip communicates with the microcontroller through the QSPI bus.
See the Building with Device Firmware Upgrade support section to learn how to change MCUboot and flash configuration in this example.
Requirements#
The application requires a specific revision of the nRF Connect SDK to work correctly. See Setting up the environment for more information.
Supported devices#
The example supports building and running on the following devices:
Hardware platform |
Build target |
Platform image |
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IPv6 network support#
The development kits for this sample offer the following IPv6 network support for Matter:
Matter over Thread is supported for
nrf52840dk_nrf52840andnrf5340dk_nrf5340_cpuapp.Matter over Wi-Fi is supported for
nrf7002dk_nrf5340_cpuapp.
Device UI#
This section lists the User Interface elements that you can use to control and monitor the state of the device. These correspond to PCB components on the platform image.
LED 1 shows the overall state of the device and its connectivity. The following states are possible:
Short Flash On (50 ms on/950 ms off) — The device is in the unprovisioned (unpaired) state and is waiting for a commissioning application to connect.
Rapid Even Flashing (100 ms on/100 ms off) — The device is in the unprovisioned state and a commissioning application is connected through Bluetooth LE.
Short Flash Off (950ms on/50ms off) — The device is fully provisioned, but does not yet have full connectivity for Thread or Wi-Fi network.
Solid On — The device is fully provisioned.
LED 2 simulates the lock bolt and shows the state of the lock. The following states are possible:
Solid On — The bolt is extended and the door is locked.
Off — The bolt is retracted and the door is unlocked.
Rapid Even Flashing (100 ms on/100 ms off during 2 s) — The simulated bolt is in motion from one position to another.
Additionally, the LED starts blinking evenly (500 ms on/500 ms off) when the Identify command of the Identify cluster is received on the endpoint 1. The command’s argument can be used to specify the duration of the effect.
Button 1 can be used for the following purposes:
Pressed for less than 3 s — Initiates the OTA software update process. This feature is disabled by default, but can be enabled by following the Building with Device Firmware Upgrade support instructions.
Pressed for more than 3 s — initiates the factory reset of the device. Releasing the button within the 3-second window cancels the factory reset procedure.
Button 2 — Pressing the button once changes the lock state to the opposite one.
On nRF52840 DK, nRF5340 DK, and nRF21540 DK: Changes the lock state to the opposite one.
On nRF7002 DK:
If pressed for less than three seconds, it changes the lock state to the opposite one.
If pressed for more than three seconds, it starts the NFC tag emulation, enables Bluetooth LE advertising for the predefined period of time (15 minutes by default), and makes the device discoverable over Bluetooth LE.
Button 4:
On nRF52840 DK, nRF5340 DK, and nRF21540 DK: Starts the NFC tag emulation, enables Bluetooth LE advertising for the predefined period of time (15 minutes by default), and makes the device discoverable over Bluetooth LE. This button is used during the commissioning procedure.
On nRF7002 DK: Not available.
SEGGER J-Link USB port can be used to get logs from the device or communicate with it using the command line interface.
NFC port with antenna attached can be used to start the rendezvous by providing the commissioning information from the Matter device in a data payload that can be shared using NFC.
Setting up the environment#
Before building the example, check out the Matter repository and sync submodules using the following command:
$ python3 scripts/checkout_submodules.py --shallow --platform nrfconnect
Note:
For Linux operating system install SEGGER J-Link Software.
Install Command Line Tools#
With admin permissions enabled, download and install the nRF Command Line Tools.
Install Toolchain Manager#
Toolchain Manager is available from nRF Connect for Desktop, a cross-platform tool that provides different applications that simplify installing the nRF Connect SDK. Both the tool and the application are available for Windows, Linux, and macOS.
To install the Toolchain Manager app, complete the following steps:
Download nRF Connect for Desktop for your operating system.
Install and run the tool on your machine.
In the APPS section, click Install button on the Toolchain Manager tab.
Install nRF Connect SDK#
Complete the following steps to install the nRF Connect SDK:
Open Toolchain Manager in nRF Connect for Desktop.
Click the Install button next to the recommended version of the nRF Connect SDK.
A pop-up window will inform you about the current installation directory. If you want to change the directory, click the Change directory button. Otherwise, click the Continue installation button.
When the nRF Connect SDK is installed on your machine, the Install button changes to the Open VS Code button.
Click the dropdown menu next to the Open VS Code button for the installed nRF Connect SDK version, and select Open terminal.
Make sure that the nRF Connect SDK version is compatible with the Matter SDK version:
$ cd {connectedhomeip directory} $ python3 scripts/setup/nrfconnect/update_ncs.py --update
Now you can proceed with the Building instruction.
Building#
Complete the following steps to build the sample:
Navigate to the example’s directory:
$ cd examples/lock-app/nrfconnect
Run the following command to build the example, with build-target replaced with the build target name of the Nordic Semiconductor’s kit you own, for example
nrf52840dk_nrf52840:$ west build -b build-target
You only need to specify the build target on the first build. See Requirements for the build target names of compatible kits.
The output zephyr.hex file will be available in the build/zephyr/ directory.
Removing build artifacts#
If you’re planning to build the example for a different kit or make changes to the configuration, remove all build artifacts before building. To do so, use the following command:
$ rm -r build
Building with release configuration#
To build the example with release configuration that disables the diagnostic features like logs and command-line interface, run the following command:
$ west build -b build-target -- -DCONF_FILE=prj_release.conf
Remember to replace build-target with the build target name of the Nordic Semiconductor’s kit you own.
Building with Device Firmware Upgrade support#
Support for DFU using Matter OTA is enabled by default.
To enable DFU over Bluetooth LE, run the following command with build-target
replaced with the build target name of the Nordic Semiconductor kit you are
using (for example nrf52840dk_nrf52840):
$ west build -b build-target -- -DCONFIG_CHIP_DFU_OVER_BT_SMP=y
To completely disable support for both DFU methods, run the following command
with build-target replaced with the build target name of the Nordic
Semiconductor kit you are using (for example nrf52840dk_nrf52840):
$ west build -b build-target -- -DCONF_FILE=prj_no_dfu.conf
Note:
There are two types of Device Firmware Upgrade modes: single-image DFU and multi-image DFU. Single-image mode supports upgrading only one firmware image, the application image, and should be used for single-core nRF52840 DK devices. Multi-image mode allows to upgrade more firmware images and is suitable for upgrading the application core and network core firmware in two-core nRF5340 DK devices.
Changing bootloader configuration#
To change the default MCUboot configuration, edit the prj.conf file located in
the child_image/mcuboot directory.
Make sure to keep the configuration consistent with changes made to the application configuration. This is necessary for the configuration to work, as the bootloader image is a separate application from the user application and it has its own configuration file.
Changing flash memory settings#
In the default configuration, the MCUboot uses the Partition Manager to configure flash partitions used for the bootloader application image slot purposes. You can change these settings by defining static partitions. This example uses this option to define using an external flash.
To modify the flash settings of your board (that is, your build-target, for
example nrf52840dk_nrf52840), edit the pm_static_dfu.yml file located in the
configuration/build-target/ directory.
Configuring the example#
The Zephyr ecosystem is based on Kconfig files and the settings can be modified using the menuconfig utility.
To open the menuconfig utility, run the following command from the example directory:
$ west build -b build-target -t menuconfig
Remember to replace build-target with the build target name of the Nordic Semiconductor’s kit you own.
Changes done with menuconfig will be lost if the build directory is deleted.
To make them persistent, save the configuration options in the prj.conf file.
Example build types#
The example uses different configuration files depending on the supported features. Configuration files are provided for different build types and they are located in the application root directory.
The prj.conf file represents a debug build type. Other build types are covered
by dedicated files with the build type added as a suffix to the prj part, as per
the following list. For example, the release build type file name is
prj_release.conf. If a board has other configuration files, for example
associated with partition layout or child image configuration, these follow the
same pattern.
Before you start testing the application, you can select one of the build types supported by the sample. This sample supports the following build types, depending on the selected board:
debug – Debug version of the application - can be used to enable additional features for verifying the application behavior, such as logs or command-line shell.
release – Release version of the application - can be used to enable only the necessary application functionalities to optimize its performance.
no_dfu – Debug version of the application without Device Firmware Upgrade feature support - can be used only for the nRF52840 DK and nRF5340 DK, as those platforms have DFU enabled by default.
For more information, see the Configuring nRF Connect SDK examples page.
Flashing and debugging#
To flash the application to the device, use the west tool and run the following command from the example directory:
$ west flash --erase
If you have multiple development kits connected, west will prompt you to pick the correct one.
To debug the application on target, run the following command from the example directory:
$ west debug
Testing the example#
Check the CLI tutorial to learn how to use command-line interface of the application.
Testing using Linux CHIPTool#
Read the CHIP Tool user guide to see how to use CHIP Tool for Linux or mac OS to commission and control the application within a Matter-enabled Thread or Wi-Fi network.
Testing using Android CHIPTool#
Read the Android commissioning guide to see how to use CHIPTool for Android smartphones to commission and control the application within a Matter-enabled Thread or Wi-Fi network.
Testing Device Firmware Upgrade#
Read the DFU tutorial to see how to upgrade your device firmware.