shutting down "spare" Cortex-M4

BradWalker · ‎2024-10-18

I've taken over this project that is using the STM32h755 CPU. The software is not currently using the Cortex-M4 processor inside the chip. I'm reworking the software so that it will be able to use it sometime in the future. But, until then, I was hoping to "turn off" the M4 to save power.

I think there is something about disabling the clocks in the RCC register for the M4 cpu. But, uncertain as if that is the propery way to go about this.

I could references to software or places in the documentation.

Thanks.

SofLit · ‎2024-10-18

You can disable CM4 with option bytes with CubeProgrammer, so you will be in Single core config:

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View solution in original post

SofLit · ‎2024-10-18

You can disable CM4 with option bytes with CubeProgrammer, so you will be in Single core config:

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.
PS: This is NOT an online support (https://ols.st.com) but a collaborative space. So please be polite in your reply. Otherwise, it will be reported as inappropriate and you will be permanently blacklisted from my help/support.

BradWalker · ‎2024-10-23

Thanks. As I'm new to the STM32 line, I was unsure where to find it.