nRF52840/nRF5340 + nRF7002 with external MCU

[djgj]

Hello,

     We are evaluating a solution for our product where we would like to use

• Zephyr RTOS with NCS
• nRF52840/nRF5340 + nRF7002 for a combined WiFi/BLE solution. nRF52/53 will run the code for both BLE and WiFi combo.
• an External MCU which is not from one of Nordic MCUs.

Is it possible to use this combination for using nRF combo only as connectivity solution?
Is there an example already on zephyr or NCS for this solution? Can you guide us to relevant samples or documents on this?

Is there anything we would need to take care in this combination? How does interfacing with nRF52/53 MCU in this case looks like?

I feel firmware update might be difficult but not impossible?

Thank you for your support.

Regards,

DJ

[AHaug]

Hi,

Is it possible to use this combination for using nRF combo only as connectivity solution?

Yes, this is possible. The nRF7002 can be used together with either the nRF52840 or the nRF5340, and we use nRF5340 in the nRF7002DK due to the addition of the netcore and the additional computational power.

You can also use this combination (52840/5340+7002) in addition to an external MCU, but you will have to create your own solutions for interfacing between them w.r.t regular "activities" and w.r.t DFU and flashing of the devices. We do unfortunately not have any out of the box solutions for how to use an external mcu in a two/three-chip solution since it's hard to create a generic 1-solution fits all potential candidates as an external MCU.

Is there an example already on zephyr or NCS for this solution? Can you guide us to relevant samples or documents on this?

You can find a list of WiFi samples here: https://docs.nordicsemi.com/bundle/ncs-2.6.99-cs1/page/nrf/samples/wifi.html and I would specially point to the BLE coexistence sample: https://docs.nordicsemi.com/bundle/ncs-2.6.99-cs1/page/nrf/samples/wifi/ble_coex/README.html as well as the Wi-Fi fundamentals course on our academy pages https://academy.nordicsemi.com/courses/wi-fi-fundamentals/ (there is also a BLE course if thats of any interest).

I would also recommend that you start with the nRF7002DK (which features the nRF5340) as a starting point w.r.t investigating the samples.

How does interfacing with nRF52/53 MCU in this case looks like?

https://docs.nordicsemi.com/bundle/ncs-2.6.99-cs1/page/nrf/device_guides/nrf70.html and the subopages under https://docs.nordicsemi.com/bundle/ncs-2.6.99-cs1/page/nrf/device_guides/working_with_nrf/nrf70/developing/index.html should explain this quite well

Let me know if this is enough to get you going!

Kind regards,
Andreas

[djgj]

Hello,

    Thank you very much for the response.
I will take a look at those documentations.

Also w.r.t interfacing options
Can you kindly suggest/share your opinion on these interfacing? which might be better in terms of simplicity? Provided we have experience working with Nordic MCUs for BLE. 

Regards,

Dhananjay

[djgj]

hello,

   Thank you for the response. which download library do you mean? is it useful for updating the firmware of nRF7002?

Regards,

djgj

[Marte Myrvold]

Hi,

The Download client library, but this was just an example of one of the helper libraries for the nRF7002.
Another thing to mention is that even though the driver is supported in upstream Zephyr, there might be helper libraries available in the nRF Connect SDK that are not in Zephyr. These are not required, but they might provide more features or better support for the nRF7002 than libraries in Zephyr.

Best regards,
Marte

[djgj]

Thank you Marte.

I will take a look at the libraries we might need.

Also is there any option to update the firmware of nRF7002 in the field?

Also do you have any comment on BLE/WiFi coexistence when using with nRF5340 vs non-nRF MCU?
Is Coexistence only supported if we use BLE softdevice Controller? will there be any support in Zephyr regarding this when using nRF7002?

regards,

djgj

[Marte Myrvold]

Hi,

djgj said:

Also is there any option to update the firmware of nRF7002 in the field?

Yes, you can update the nRF7002 firmware in the field. We do not have any samples showing the complete process of this as of now, but the Download client sample can be used as a starting point for downloading a firmware update. After the firmware image is downloaded, you can use the available DFU alternatives described in the Device Firmware Updates page. You can find more information in the nRF70 Series - Firmware patch update page.

djgj said:

Also do you have any comment on BLE/WiFi coexistence when using with nRF5340 vs non-nRF MCU?
Is Coexistence only supported if we use BLE softdevice Controller? will there be any support in Zephyr regarding this when using nRF7002?

If the host MCU uses the SoftDevice Controller, you can use coexistence based on the Short-Range Protocols External Radio Coexistence provided by the Multiprotocol Service Layer (MPSL) library, also called the MPSL CX API. The nRF Connect SDK provides a wrapper that configures coex based on devicetree and Kconfig options. You can read more about this in Coexistence based on MPSL CX API and nRF70 Series Wi-Fi coexistence.

With a third-party host, the specific details of Bluetooth and Wi-Fi coexistence might depend on the host's capabilities and configurations. We do have some general information on coexistence in nRF70 Series Bluetooth LE/IEEE 802.15.4 Coexistence and in the nRF7002 datasheet.

Best regards,
Marte

[djgj]

Thank you very much Marte,

* Regarding nRF7002 firmware update, do you know if it will work when i use the non-nRF MCU with MCUboot bootloader? Documentation only mentions about using with nRF5340 or nRF52840. My concern is how do i use `CONFIG_NRF_WIFI_FW_PATCH_DFU` when using non-nRF MCU? 

* Regarding Coexistence, i have gone through documentations. However i am entirely not sure how i can make use of this with non-nRF host MCU?

This is my rough setup and we can assume that non-nRF MCU will be similar to nRF5340 in terms of memory and Capabilites. 

I will run zephyr BLE host implementation on non-nRF MCU.

However, i cannot run soft device controller on my non-nRF MCU due to Nordic license.
On nRF5340, i can either run softdevice BLE controller or zephyr BLE controller. 

We have COEX pins (REQ, GRANT, STATUS) from nRF7002, Should these pins be connected to nRF5340 or non-nRFMCU for ensuring BLE& WiFi coexistence?

* Will the coexistence be simplified if i use softdevice controller on my nRF5340 (netcore)?

* Will there any code needed on non-nRF MCU to ensure CoEx support?

* I also saw that in the recent nRF7002 zephyr upstream, coex files are also pushed like
https://github.com/zephyrproject-rtos/zephyr/blob/878640fa0817a5c6684758d68dcb824e24571612/drivers/wifi/nrfwifi/src/coex.c
Where should i use these APIs non-nRF or nRF5340 MCU for coexistence?

* If i understand from this sample application: https://github.com/nrfconnect/sdk-nrf/blob/main/samples/wifi/ble_coex/src/main.c
we should ensure that COEX pins are connected in HW and configured in DTS file and then call the coex APIs in the application?

Thanks for your support.

Regards,

djgj

[Marte Myrvold]

Hi,

I have forwarded your questions internally, and I will get back to you early next week.

Best regards,
Marte

[Marte Myrvold]

Hi,

I have not received a reply yet but have asked for an update. I will update you when I hear back.

Best regards,
Marte