STM32H755 Difference between M4 and M7

[TDP_0000]

MPU:STM32H755XI6

Connection with PC:USART1

RTOS:Zephyr

In order to install Zephyr into STM32H755XIH6, if you build and burn images for M4 and M7, the M4 side will start but the M7 side will not.

The content is LED flashing of PG10 (A9pin).

Are there any signals that cannot be used with M4 and M7?

For example, only M4 can connect to Ether, and only M7 can use SDIO.

[SofLit]

Hello,

I'm not expert of Zephyr RTOS.

Regarding your question:

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@TDP_0000 wrote:

Are there any signals that cannot be used with M4 and M7?

For example, only M4 can connect to Ether, and only M7 can use SDIO.

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The answer is given in the RM0399 / Table 2. Bus-master-to-bus-slave interconnect 

ETH and SDMMC are masters like Cortex-M7 and Cortex-M4 and you can use ETH and SDMMC either on Cortex-M7 or Cortex-M4 but you need to ensure that the shared memory between ETH/SDMMC is accessible by the Cortex-M. For that you need to check that in the table above.

[TDP_0000 · Accepted solution]

Thank you for your confirmation.

The cause was the clock settings on Zephyr.This was because the external clock was set on the M7 even though the external clock was not on the HW.

I was able to confirm the operation by setting the internal clock.

I appreciate your help.