Use nrf7002 DK for Matter over Thread Light Bulb example

[rlk0]

nRF Connect SDK v3.2.1 on Windows 11

I am trying to build the Matter Light Bulb sample using a nRF7002DK but run it over Thread instead of WiFi (the default). Since this example supports the nRF5340 DK using Thread, it seems like it should be possible to do this by effectively ignoring the nRF7002 on the DK. The example builds and runs fine as a WiFi app. After looking at the config files for the nRF5340 DK vs the nRF7002 DK I found that the following sysbuild.conf would result in an output zephr/.config file that was essentially identical for the two platforms (other than 3 lines reflecting the DK being used).

SB_CONFIG_MATTER=y
SB_CONFIG_WIFI_NRF70=n
#SB_CONFIG_NETCORE_HCI_IPC=y
SB_CONFIG_NETCORE_IPC_RADIO=y

It builds, but fails at boot with the following:

*** Using nRF Connect SDK v3.2.1-d8887f6f32df ***
*** Using Zephyr OS v4.2.99-ec78104f1569 ***
I: 136 [DL]BLE address: DE:9D:2C:56:2A:B5
E: Endpoint binding failed with -11
E: HCI driver open failed (-11)
E: 2148 [DL]BLEManager initialization failed: 200000b
E: PlatformMgr().InitChipStack() failed [Error: 0]
E: Exited with code 200000b

Based on searching the DevZone, I tried also uncommenting the SB_CONFIG_NETCORE_HCI_IPC=y, but that made no difference. 

Any ideas on what is wrong?

[rlk0]

After more digging through config files, I finally found that adding CONFIG_CHIP_WIFI=n to prj.conf fixed the issue.

[Samruddhi Jadhav]

Hi,

Your solution of adding CONFIG_CHIP_WIFI=n to proj.conf seems right. CONFIG_CHIP_WIFI tells Matter that the device uses Wi-Fi. So, by setting it to "n", the stack stops running in Wi-Fi mode which is what you want for a Thread only build. 

Best Regards,

Samruddhi