How to know CPU working frequency and enabled cores - STM32H747I-DISCO

Hello everyone,

I am an owner of an STM32H747I-Discovery kit, I am playing with it trying some stuffs.
For a case study now I would like to know at which frequency is running the uC, I know that the board has two cores that can work at different frequency (480 MHz ARM Cortex M7 and 240 MHz Cortex M4).
I am wondering if it possible to program the board to enable just one of the two cores and to know at which frequency it is working.

I am sorry if the question is too general and I hope it is clear.

Thank you very much to who will help.


I do not have this piece of hardware so I have not personal experience with that but I will try to make an answer.

According to this, there is DISCO_H747I which is probably used by the Oline Compiler by default, and that use only Cortex M7. In the Mbed Studio is also available DISCO_H747I_CM7 (DISCO_H747I inherit from it) and DISCO_H747I_CM4.
The Mbed do not know to use multicore, so one core = one standalone project.

For the CPU speed check I use this

printf("CPU SystemCoreClock is %d Hz\r\n", SystemCoreClock);

BR, Jan


Maybe some answer is in