How to Interface wifi module with 2 MCUs: STM32N6 & STM32U5

[sakshi]

Hello All,

We are developing 2 MCU (STM32U5 and STM32N6) based solution which has a Wi-Fi module. There is a need that should allow either STM32U5 or STM32N6 to communicate with ST67W611M1A6BTR Wi-Fi module at any given time. The FW is under our control, and we know that at any given time only one MCU will interact with Wi-Fi module. Do I need to use a multiplexer to decide which MCU to communicate or is it possible with the help of FW. Please suggest what needs to be done on schematic and FW.

Regards,

Sakshi 

[TDK]

There's probably 100 different ways to do this.

Have one STM32 be the master and have the other request access by raising a GPIO. The master would respond by raising a different GPIO to let the other chip know it can use the wifi.

[sakshi]

Hi @TDK 

Thanks for the solution but is thr any hardware refrence which I can take up.

Regards

Sakshi

[Andrew Neil]

I think the best approach is likely to be to have the WiFi dedicated to just one MCU, and have the other MCU go via that MCU.

+-------+          +-------+          +-------+
|       |          |       |          |       |
| MCU 1 |<========>| MCU 2 |<========>| WiFi  |
|       |          |       |          |       |
+-------+          +-------+          +-------+

Otherwise, both MCUs are going to have to keep each other updated at all times with the current state of the WiFi.

Or they'll both have to spend a lot of time querying the WiFi to find what state it is currently in before they can use it for anything.

Whatever you do, you'll need comms between the MCUs to know when the WiFi is "busy" or available for use...

PS:

This also means that you only have to implement the WiFi stuff in one microcontroller - instead of having to duplicate it on both.

[Andrew Neil]

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@sakshi wrote:

is thr any hardware refrence which I can take up.

---

I doubt it.

The normal use case is that the WiFi module has just one "Host"