The nRF Connect Lighting Example demonstrates how to remotely control a white dimmable light bulb. It uses buttons to test changing the lighting 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 supports remote access and control of a lighting over a low-power, 802.15.4 Thread 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. The device works as a Thread Router.
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.
The Matter device that runs the lighting application is controlled by the Matter controller device over the Thread protocol. By default, the Matter device has Thread disabled, and it should be paired with Matter controller and get configuration from it. Some actions required before establishing full communication are described below.
The example can be configured to use the secure bootloader and utilize it for performing over-the-air Device Firmware Upgrade using Bluetooth LE.
To commission the device onto a Matter network, the device must be discoverable over Bluetooth LE that starts automatically upon the device startup, but only for a predefined period of time (15 minutes by default). If the Bluetooth LE advertising times out, you can re-enable it manually using Button 4.
In Matter, 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. NFC tag emulation starts automatically when Bluetooth LE advertising is started and stays enabled until Bluetooth LE advertising timeout expires.
Last part of the rendezvous procedure, the provisioning operation involves sending the Thread network credentials from the Matter controller to the Matter device. As a result, device is able to join the Thread network and communicate with other Thread devices in the network.
The example supports over-the-air (OTA) device firmware upgrade (DFU) using one of the two available methods:
For both methods, the MCUboot bootloader solution is used to replace the old firmware image with the new one.
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 (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.
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.
The application requires a specific revision of the nRF Connect SDK to work correctly. See Setting up the environment for more information.
The example supports building and running on the following devices:
| Hardware platform | Build target | Platform image |
|---|---|---|
| nRF52840 DK | nrf52840dk_nrf52840 | nRF52840 DK |
| nRF5340 DK | nrf5340dk_nrf5340_cpuapp | nRF5340 DK |
| nRF52840 Dongle | nrf52840dongle_nrf52840 | nRF52840 Dongle |
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.
Note:
The following Device UI elements are missing on the nRF52840 Dongle: Button 2, Button 3, Button 4, SEGGER J-Link USB port, and NFC port with antenna attached. You can collect logs from the nRF52840 Dongle using the nRF USB port instead of the SEGGER J-Link USB port. Functionalities associated with the remaining missing elements are inaccessible.
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 Thread network or service connectivity.
Solid On — The device is fully provisioned and has full Thread network and service connectivity.
LED 2 simulates the light bulb and shows the state of the lighting. The following states are possible:
Solid On — The light bulb is on.
Off — The light bulb is off.
LED 3 can be used to identify the device. The LED starts blinking evenly (500 ms on/500 ms off) when the Identify command of the Identify cluster is received. 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 6 s — Initiates the factory reset of the device. Releasing the button within the 6-second window cancels the factory reset procedure. LEDs 1-4 blink in unison when the factory reset procedure is initiated.
Pressed for less than 3 s — Initiates the OTA software update over Bluetooth LE process. This feature is disabled by default, but can be enabled by following the Building with Device Firmware Upgrade support instruction.
Button 2 — Pressing the button once changes the lighting state to the opposite one.
Button 4 — Pressing the button once starts the NFC tag emulation and enables Bluetooth LE advertising for the predefined period of time (15 minutes by default).
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.
Before building the example, check out the Matter repository and sync submodules using the following command:
```
$ git submodule update --init
```
The example requires a specific revision of the nRF Connect SDK. You can either install it along with the related tools directly on your system or use a Docker image that has the tools pre-installed.
If you are a macOS user, you won't be able to use the Docker container to flash the application onto a Nordic development kit due to certain limitations of Docker for macOS. Use the native shell for building instead.
To use the Docker container for setup, complete the following steps:
If you do not have the nRF Connect SDK installed yet, create a directory for it by running the following command:
``` $ mkdir ~/nrfconnect ```
Download the latest version of the nRF Connect SDK Docker image by running the following command:
``` $ docker pull nordicsemi/nrfconnect-chip ```
Start Docker with the downloaded image by running the following command, customized to your needs as described below:
```
$ docker run --rm -it -e RUNAS=$(id -u) -v ~/nrfconnect:/var/ncs -v ~/connectedhomeip:/var/chip \
-v /dev/bus/usb:/dev/bus/usb --device-cgroup-rule "c 189:* rmw" nordicsemi/nrfconnect-chip
```
In this command:
Update the nRF Connect SDK to the most recent supported revision, by running the following command:
``` $ cd /var/chip $ python3 scripts/setup/nrfconnect/update_ncs.py --update ```
Now you can proceed with the Building instruction.
To use the native shell for setup, complete the following steps:
Download and install the following additional software:
If you do not have the nRF Connect SDK installed, follow the guide in the nRF Connect SDK documentation to install the latest stable nRF Connect SDK version. Since command-line tools will be used for building the example, installing SEGGER Embedded Studio is not required.
If you have the SDK already installed, continue to the next step and update the nRF Connect SDK after initializing environment variables.
Initialize environment variables referred to by the Matter and the nRF Connect SDK build scripts. Replace nrfconnect-dir with the path to your nRF Connect SDK installation directory, and toolchain-dir with the path to GNU Arm Embedded Toolchain.
``` $ source nrfconnect-dir/zephyr/zephyr-env.sh $ export ZEPHYR_TOOLCHAIN_VARIANT=gnuarmemb $ export GNUARMEMB_TOOLCHAIN_PATH=toolchain-dir ```
Update the nRF Connect SDK to the most recent supported revision by running the following command (replace matter-dir with the path to Matter repository directory):
``` $ cd matter-dir $ python3 scripts/setup/nrfconnect/update_ncs.py --update ```
Now you can proceed with the Building instruction.
Complete the following steps, regardless of the method used for setting up the environment:
Navigate to the example's directory:
``` $ cd examples/lighting-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.
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 ```
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.
The RPCs in lighting-common/lighting_service/lighting_service.proto can be used to control various functionalities of the lighting app from a USB-connected host computer. To build the example with the RPC server, run the following command with build-target replaced with the build target name of the Nordic Semiconductor's kit you own:
``` $ west build -b build-target -- -DOVERLAY_CONFIG=rpc.overlay ```
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.
Currently the multi-image mode is only available for the DFU over Bluetooth LE method.
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.
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.
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.
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:
For more information, see the Configuring nRF Connect SDK examples page.
The flashing and debugging procedure is different for the development kits and the nRF52840 Dongle.
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
```
Visit Programming and Debugging nRF52840 Dongle to read more about flashing on the nRF52840 Dongle.
Check the CLI tutorial to learn how to use command-line interface of the application.
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 network.
Read the DFU tutorial to see how to upgrade your device firmware.
If the flashed device has been built with the pigweed RPCs, the RPC console can be used to interact with the device.
Build or install the rpc console
Start the console
```
$ chip-console --device /dev/ttyUSB0
```
From within the console you can then invoke rpcs:
```python
rpcs.chip.rpc.Lighting.Get()
rpcs.chip.rpc.Lighting.Set(on=True, level=128, color=protos.chip.rpc.LightingColor(hue=5, saturation=5))
```
Device tracing is available to analyze the device performance. To turn on tracing, build with RPC enabled. See Using the RPC console.
Obtain tracing json file.
$ ./{PIGWEED_REPO}/pw_trace_tokenized/py/pw_trace_tokenized/get_trace.py -d {PORT} -o {OUTPUT_FILE} \
-t {ELF_FILE} {PIGWEED_REPO}/pw_trace_tokenized/pw_trace_protos/trace_rpc.proto