Matter K32W1 Lighting Example Application

For generic information related to on/off light application, please see the common README.

• Matter K32W1 Lighting Example Application
  • Introduction
  • Device UI
  • Building
    • SMU2 Memory
    • LED PWM
  • Flashing
    • Flashing the NBU image
    • Flashing the host image
  • Debugging
  • Running RPC console
  • OTA

Introduction

This is an on/off lighting application implemented for a k32w1 device.

The following board was used when testing this Matter reference app for a k32w1 device:

Device UI

The state feedback is provided through LED effects:

widget	effect	description
LED2	short flash on (50ms on/950ms off)	The device is in an unprovisioned (unpaired) state and is waiting for a commissioner to connect.
LED2	rapid even flashing (100ms period)	The device is in an unprovisioned state and a commissioner is connected via BLE.
LED2	short flash off (950ms on/50ms off)	The device is fully provisioned, but does not yet have full network (Thread) or service connectivity.
LED2	solid on	The device is fully provisioned and has full network and service connectivity.
RGB LED	on	The OnOff attribute of the On/Off cluster is true (simulating device turned on).
RGB LED	off	The OnOff attribute of the On/Off cluster is false (simulating device turned off).

NOTE: LED2 will be disabled when OTA is used. On K32W1 EVK board, PTB0 is wired to both LED2 and CS (Chip Select) of the External Flash Memory. Since the OTA image is stored in external memory, LED2 operations will affect OTA operation by corrupting packages and OTA will not work.

The user actions are summarized below:

button	action	output
SW2	short press	Enable BLE advertising
SW2	long press	Initiate a factory reset (can be cancelled by pressing the button again within the factory reset timeout limit - 6 seconds by default)
SW3	short press	Toggle attribute OnOff value
SW3	long press	Clean soft reset of the device (takes into account proper Matter shutdown procedure)

The example application provides a simple UI that depicts the state of the device and offers basic user control. This UI is implemented via the general-purpose LEDs and buttons built in the K32W1 EVK board.

Building

Manually building requires running the following commands:

user@ubuntu:~/Desktop/git/connectedhomeip$ cd examples/lighting-app/nxp/k32w1
user@ubuntu:~/Desktop/git/connectedhomeip/examples/lighting-app/nxp/k32w1$ gn gen out/debug
user@ubuntu:~/Desktop/git/connectedhomeip/examples/lighting-app/nxp/k32w1$ ninja -C out/debug

Please note that running gn gen out/debug without --args option will use the default gn args values found in args.gni.

After a successful build, the elf and srec files are found in out/debug/. See the files prefixed with chip-k32w1-light-example.

SMU2 Memory

Additional memory is provided to the application by moving some Matter instances and global variables in the shared memory area from NBU domain.

Note: These instances and global variables are placed in SMU2 memory through name matching in the application linker script. They should not be changed or, if changed, the names must be updated in app.ld. See app.ld for names and SMU2 memory range size.

When compiling the application as an OT Full Thread Device (chip_openthread_ftd=true), using use_smu2_static=true gn arg will cause the following symbols to be moved to SMU2 area:

symbol name	file
gImageProcessor	OTAImageProcessorImpl.cpp
gApplicationProcessor	OTAHooks.cpp
Server::sServer	Server.cpp
ThreadStackManagerImpl::sInstance	ThreadStackManagerImpl.cpp

Additionally, using use_smu2_dynamic=true will cause the OpenThread buffers to be dynamically allocated from a 13KB SMU2 range after a successful commissioning process.

use_smu2_static and use_smu2_dynamic are set to true in the default example.

LED PWM

In the default configuration, the onboard RGB LED pins are configured as GPIO pins. In order to enable the dimming feature, the pins need to be configured in PWM mode and synced with channels of the TPM (Timer PWM Module). To enable this feature, compile the application with: chip_config_dimmable_led=true

If the feature is enabled, the LED brightness can be controlled using LevelControl cluster commands.

Flashing

Two images must be written to the board: one for the host (CM33) and one for the NBU (CM3).

The image needed on the host side is the one generated in out/debug/ while the one needed on the NBU side can be found in the downloaded NXP-SDK package at path - middleware\wireless\ieee-802.15.4\bin\k32w1\k32w1_nbu_ble_15_4_dyn_matter.sb3.

Flashing the NBU image

NBU image should be written only when a new NXP-SDK is released.

K32W148 board quick start guide can be used for updating the NBU/radio core:

• Section 2.5 – Get Software – install SPSDK (Secure Provisioning Command Line Tool)
• Section 3.3 – Updating NBU for Wireless examples - use the corresponding .sb3 file found in the SDK package at path middleware\wireless\ieee-802.15.4\bin\k32w1\

Flashing the host image

Host image is the one found under out/debug/. It should be written after each build process.

If debugging is needed then jump directly to the Debugging section. Otherwise, if only flashing is needed then JLink 7.84b or greater can be used:

• Plug K32W1 to the USB port (no need to keep the SW4 button pressed while doing this, e.g. ISP mode is not needed for host flashing)

• Connect JLink to the device:

  JLinkExe -device K32W1480 -if SWD -speed 4000 -autoconnect 1
  

• Run the following commands:

  reset
  halt
  loadfile chip-k32w1-light-example.srec
  reset
  go
  quit
  

Debugging

One option for debugging would be to use MCUXpresso IDE.

• Drag-and-drop the zip file containing the NXP SDK in the “Installed SDKs” tab:

• Import any demo application from the installed SDK:

Import SDK example(s).. -> choose a demo app (demo_apps -> hello_world) -> Finish

• Flash the previously imported demo application on the board:

Right click on the application (from Project Explorer) -> Debug as -> JLink/CMSIS-DAP

After this step, a debug configuration specific for the K32W1 board was created. This debug configuration will be used later on for debugging the application resulted after ot-nxp compilation.

• Import Matter repo in MCUXpresso IDE as Makefile Project. Use none as Toolchain for Indexer Settings:

File -> Import -> C/C++ -> Existing Code as Makefile Project

• Replace the path of the existing demo application with the path of the K32W1 application:

Run -> Debug Configurations... -> C/C++ Application

Running RPC console

To build example with RPC enabled, use the following gn command: gn gen out/debug --args='import("//with_pw_rpc.gni") treat_warnings_as_errors=false'

The application runs an RPC server and processes events coming from an RPC client. An example of an RPC client is the chip-console, which can be accessed by running: chip-console --device /dev/tty.<SERIALDEVICE> -b 115200 -o pw_log.out

The console should have already been installed in the virtual environment. From the chip-console, a user can send specific commands to the device.

For button commands, please run rpcs.chip.rpc.Button.Event(idx=index) based on the table below:

index	action
0	Start/stop BLE advertising
1	Factory reset the device
2	Application specific action (e.g. toggle LED)
3	Soft reset the device

To reboot the device, please run rpcs.chip.rpc.Device.Reboot().

OTA

Please see k32w1 OTA guide.