How to debug Stm32H755 Cm4 Core to get SPI clock running.

[ACand.3]

Hey Everyone, 

I am having an issue with the stm32h755 dual debugging. Im trying to run cm4 by itself without cm7. 

But the issue im having is, whenever I reset the MCU and check the SPI lines, I see a clock running. When I debug just cm4, I do not see the SPI clock at all. As if my Cm4 is not running on its own properly. 

Is there a way I can debug just the cm4 inside the stm32h755? 

I did follow guides online, I have halt all cores unchecked, I setup the flashing correctly as well.  

[Imen.D]

Hello @ACand.3 , 

If the two applications on CM4 and CM7 are independent, you may only connect the CM4 for debug and let the CM7 running. When CM4 debugs, CM7 must be run and wake up the CM4 in advance.

I advise you to have a look on application note AN5286. It provides guidelines for the debug applications which run on the STM32H7x5/x7 Dual-core microcontrollers. 

• AN5286 STM32H7x5/x7 dual-core microcontroller debugging (In order to debug only CM4, please follow the described steps on "CM4-project configuration")
• AN5361 Getting started with projects based on dual-core STM32H7 microcontrollers in STM32CubeIDE 

[ACand.3]

Hi Imen, this is what I have for CM4 and CM7. 

The only way I can have spi running is if I run both cores at the same time ( I select both main threads to run) and then I can see the spi working on cm4. But my other issue is, I have a breakpoint on my cm4 code before calling spi, but when I click "resume" on both main threads, the debugger skips the breakpoint and proceeds with my code. 

[ACand.3 · Accepted solution]

Hey everyone, I had to reinstall the vendors bootloader and it started working. 

I can now debug cm4 on its own without debugging cm7. 
I am not sure exactly how, but I do want to thank @Imen.D  for responding. 

Thank You very much