How to Write Correct Sleep Function for WB55?

[Ygt]

I want to write a function for the STM32WB55 where BLE advertising is always active, and the processor performs the necessary tasks, then sleeps and wakes up using RTC Wakeup.

I want to do it with STOP2 mode, but my processor consumes 3mA and does not enter sleep mode. Instead of doing this through CubeMX, I want to manually put it to sleep whenever I choose, but I haven't been successful. 

Could you show me an example or a resource I can refer to for this?

[Remy ISSALYS]

Hello,

You can look BLE_HeartRate example available in STM32CubeWB package. By default, this application is configured to perform STOP2 low power mode while BLE is running.  Then, you can use the HW timer server module to wake up the system, this module is based on RTC, see HW_TS_Create, HW_TS_Start, HW_TS_Stop APIs. 

Best Regards, 

[Ygt]

I have issues with low power in the project i am developing. As mentioned above, I want the device to always advertising and connectable. I know that the low power features of CPU1 and CPU2 operate independently, and I am trying to configure them accordingly.

For CPU2, I enable LPM Supported through CubeMX, and for CPU1, I try to configure it in the code as shown in the screenshot. I carefully follow the warnings in the Errata document while making these adjustments.

Despite performing all these steps, my custom board draws approximately 250µA, and the advertising stops, plus it does not wake up with the RTC Wakeup. I have tried many things but have not made any progress.  

Note: I tried running it in STOP1 mode because I read comments suggesting that this mode operates more stably.

Looking Forward to Your Response,