Matter MCXW71 Contact Sensor Example Application

For generic information related to contact sensor application, please see the common README.

• Matter MCXW71 Contact Sensor Example Application

  • Introduction

  • Device UI

  • Building

  • Flashing

    • Flashing the NBU image

    • Flashing the host image

  • Debugging

  • OTA

Introduction

This is a contact sensor application implemented for an mcxw71 device.

The following board was used when testing this Matter reference app for an mcxw71 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 StateValue attribute of the BooleanState cluster is true (simulating detection).
RGB LED	off	The StateValue attribute of the BooleanState cluster is false (simulating no detection).

NOTE: LED2 will be disabled when OTA is used. On FRDM-MCXW71 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	state	output
SW2	short press	not commissioned	Enable BLE advertising
SW2	short press	commissioned + device is LIT	Enable Active Mode
SW2	long press	NA	Initiate a factory reset (can be cancelled by pressing the button again within the factory reset timeout limit - 6 seconds by default)
SW2	double press	commissioned + device is LIT + supports DSLS	Enable / Disable SIT Mode
SW3	short press	NA	Toggle attribute StateValue value
SW3	long press	NA	Clean soft reset of the device (takes into account proper Matter shutdown procedure)

Building

Manually building requires running the following commands:

user@ubuntu:~/Desktop/git/connectedhomeip$ cd examples/contact-sensor-app/nxp/mcxw71
user@ubuntu:~/Desktop/git/connectedhomeip/examples/contact-sensor-app/nxp/mcxw71$ gn gen out/debug
user@ubuntu:~/Desktop/git/connectedhomeip/examples/contact-sensor-app/nxp/mcxw71$ 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-mcxw71-contact-example.

Flashing

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

Flashing the NBU image

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

1. Install Secure Provisioning SDK tool using Python:

   pip install spsdk
   

   Note: There might be some dependencies that cause conflicts with already installed Python modules. However, blhost tool is still installed and can be used.

2. Updating NBU for Wireless examples

   It is necessary to work with the matching NBU image for the SDK version of the application you are working with. This means that when you download your SDK, prior to loading any wireless SDK example, update your NBU image with the SDK provided binaries. For FRDM users, please write the following binary:

   middleware\wireless\ieee-802.15.4\bin\mcxw71\mcxw71_nbu_ble_15_4_dyn_matter_<nbu_version>.sb3

   Please note that <nbu_version> may vary depending on the SDK version.

   1. Place your device in ISP mode.

      • Make sure a jumper is placed on JP25

      • Press and hold SW4, press and release Reset, then release SW4

   2. Once the device is connected, you may find the assigned port by running:

      nxpdevscan
      

   3. Run the blhost command to write the sb3 file:

      blhost -p <assigned_port> receive-sb-file <path_to_SDK>\middleware\wireless\ieee-802.15.4\bin\mcxw71\mcxw71_nbu_ble_15_4_dyn_matter_<nbu_version>.sb3
      

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 can be used:

• Plug MCXW71 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 MCXW71 -if SWD -speed 4000 -autoconnect 1
  

• Run the following commands:

  reset
  halt
  loadfile chip-mcxw71-contact-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 MCXW71 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 MCXW71 application:

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

OTA

Please see mcxw71 OTA guide.