How to wake up CPU1 with RF subsystem?

[FDumontKeller]

Hi everybody, 

how can the CPU1 of module STM32WB5MMG be waken up by the RF subsystem?
The idea in mind is to use the module as a BLE Server, have the CPU2 perform advertising while the CPU1 is in STOP2 mode. 
According to the reference manual RM0434, this could be done? 

And in the Datasheet of STM32WB55xx, the RF is listed as a possible wake up source as well.

Waking up with the the RTC, an EXTI event and EXTI interrupt worked, but the CPU2 stops its advertising shortly after the CPU1 goes to STOP2 mode, even though the low power mode for the CPU2 is disabled. 

I thought that the CPU2 would continue the adversiting and either the EXTI listed as "CPU2 SEV interrupt..." or "PWR switching on the fly, ..." could wake up the CPU1 if a connection is requested from the client. 

Obviosly I am missing somehting, does anybody has an idea of what am I getting wrong?

Thanks in advance!

[STTwo-32 · Accepted solution]

Hello @FDumontKeller 

Yes, it is possible for the M4 core to enter the stop2 mode while keeping the M0+ core advertising. The LPM manager is managing it. Note that there is no need to wake up the M4 core when a scan request is received by the MO+. The data to be inserted in the scan response is managed by the M0+ core alone.

Best regards.

STTwo-32

[FDumontKeller]

Hi @STTwo-32, 
After reading in more detail how the LPM works and manages the transisions of between low power modes while using a BLE application, it is more clear to me how to use it. 

thanks for the answer!!
Best Regards.