About STM32WBA25 RAM Size for Multiple Functions

[CY_Tsai]

Hi

If I develop an application using the STM32WBA25 MCU with BLE, ThreadX, and USBX, is the RAM size sufficient?

[Pavel A.]

96KB looks like decent amount of RAM  - but RTOSes such as ThreadX require a lot of RAM for thread stacks. So it highly depends on the number of your tasks/threads. 

[CY_Tsai]

Hi @Pavel A. ,

Given that my application includes approximately 3 KB of historical data, a CC protocol using the FUSB302B, and a USBX CDC stack requiring at least 12 KB of memory, would you recommend continuing development with the STM32WBA25 series?

Sincerely.

Eric

[Pavel A. · Accepted solution]

Eric,

It looks feasible, but actually depends on the application RAM usage, on the compiler (some compilers optimize better) so it's hard to tell. Do you have alternatives?

[CY_Tsai]

Hi @Pavel A.,

Previously, I used the STM32WBA62 MCU, which provides a large RAM capacity, allowing flexible memory allocation. However, when using the same configuration on the STM32WBA25, I must carefully optimize memory usage to ensure the program fits within the available RAM. Therefore, I want to make sure the RAM size is sufficient before designing the MCU into my project.

Sincerely.

Eric

[Imen.D]

Hi @CY_Tsai 

You can find more information about STM32WBA memory requirement and consideration on the wiki page: 

STM32WBA Zigbee/BLE memory requirements

[CY_Tsai]

Hi @Imen.D ,

Thank you for your response. I would like the MCU to support both BLE and USB functionality. Currently, only the WBA2x and WBA6x series meet these requirements. Considering functionality and cost, the WBA2x appears to be the preferred option. The only remaining concern is the RAM size. To mitigate this risk, I plan to design and fabricate a test board to evaluate overall system stability.

Sincerely,

Eric

[Imen.D]

Hi @CY_Tsai ,

You are right. Both STM32WBA2x and STM32WBA6x series support BLE and USB: 

STM32WBA2 wireless MCU series overview

Regarding the RAM size, validating with a dedicated test board is the correct approach. This will help ensure the application fits within constraints and allows you to assess RAM usage.

Please feel free to share your findings with Community users and don't hesitate to ask for support during your evaluation phase if needed.

Thank you for your contribution.

[CY_Tsai]

Hi @Imen.D, 

I am currently designing the PCB and preparing the peripheral components. I expect to begin experiments within one to two weeks. I hope I will be able to successfully complete the project.

Sincerely,

Eric