Running an AI model in Low-Power?

[F F]

Hi,

I'm working on an application on a STM32WB55 which is sampling sensor data with 52Hz and feed it into a Keras model. Both the raw sampling sensor data as the output of the model will be saved to external flash memory (every 64 samples). A 52Hz interrupt DRDY signal will trigger to start a sample. The device will sample the data for several hours a day. At the end of the day all data will be offloaded over BLE. So in the project the BLE stack is included as well. Now I wonder if I can add some low-power features to this project.

I would like to have some advice:

• My clock (HSE/ sysclock) are now running on 32 MHz. Is this something I can lower when running an AI model?
• Any advice on which mode is possible (like low-power RUN/SLEEP/STOP) ?
• Is it possible to shutdown CPU2 (BLE core) while CPU1 is running the AI code / sampling data?

I hope one of you can help me with one or more of above questions.

Thanks already!

[Remy ISSALYS]

Hello,

You can reduce the CPU1 frequency according to your need for your AI model. You can perform STOP2 low power mode using low power manager. You can look BLE_HeartRate example which allow to do STOP2 low power mode.

If there isn't any RF activity the consumption of CPU2 is very close to the consumption when the CPU2 is shutdown.

Best Regards