Flashing procedure for dual-core processor on STM32 H755 ZI-Q board.

[Ankita]

I am trying to flash and debug on CM4 on stm32 H755 ZI-Q board.

1. Firstly i tried debugging CM7 , with debug configurations --> Connecting under reset and halt all cores.
2. Then i tried debugging CM4, with debug configuration -->None(no reset)
3. Also added .elf files in startup while debugging CM7.
4. I separately debugged cm7 and then cm4, but got only cm7 prints output.
5. So then i tried in other way,
I launch the group debug, adding cm4 and cm7 both elf files,, still the cm7 i could able to see prints,, cm4 no prints.. basically, I think cm4 is not able to get up from stop mode.

So, provide me solution

1.How to run cm4 independently?

If this is not possible, 

2. How to run the code written in m4, along with m7 in stm32 h755 zi-q series board.

[Andrew Neil]

Welcome to the forum.

Please give some more detail - see How to write your question to maximize your chances to find a solution for best results.

[Ankita]

Regarding STM32 H755 ZI-Q board, (which has dual processor CM7 and CM4)

I was working on CM7 (which acts as master and initializes clock) on the dual core board, was trying to print some random statement using printf. I was successfully able to see the prints using UART on console.

Now I want to work CM4(according to my project requirements)
Firstly the set-up what i did was,
In debug configuration(of CM7)--> 1. checked the box for the connect under reset and halted all cores.

                                                      2.In startup, i have added .elf files of cm7 and cm4 both(no need to download the elf file for cm4 again)

In debug configuration(of CM4)--> 1. checked the box for the none  for reset.

I debugged first CM7 and then tried to debug CM4. But i am able to see prints of cm4, successfully able to debug and flash cm7.
i also tried doing group launch(from cm7 debug configurations), debugging both cores together, still couldnt see cm4 prints.

Please provide me solution 
1. How to flash or debug CM4 independently(of CM7)?

2. If the above is not possible, How to run the code and see prints of cm4 (with cm7)?

note: cm7 initializes the clock, acts as master. Initially it executes, it sends semaphore message for activation of CM4, if CM4 didn't able to get up from stop mode, then it can't run or execute the code.

I am using UART ,
Initially I used UART3 for both CM7 and CM4, i tried the same, only cm7 prints i was able to see.
I also changed later, UART3 for Cm7 and UART2 for cm4.

[Andrew Neil]

You still haven't said

• What board is it ?
• What tools are you using, and versions?
• etc.

[mƎALLEm]

Hello @Ankita and welcome to the ST community,

You need to bear in mind that when you generate a code with CubeMx for STM32H7 Dual core, there is a synchronization mechanism between the cores and M4 enters the low power mode waiting M7 to configure the system including the clocks then it wakes up M4. You can't debug M4 while in low power mode. So I recommend first to comment the line:

#define DUAL_CORE_BOOT_SYNC_SEQUENCE

This excludes the synchronization between the cores. Note you need to do that just to test CM4, but if you need CM7 to configure the system before making M4 to start, you need to enable that synchronization.