Is there any sample source code that implements the transfer from Cortex-A to Cortex-M?

[HMasu.1]

I want to implement the program that exchange large data with each other on Cortex-A7 and Cortex-M4 by using DDR.

Thanks to following wiki page, I have understand the mechanism that exchange large data from Cortex-M4 to Cortex-A7 by using DDR.

https://wiki.st.com/stm32mpu-ecosystem-v1/wiki/How_to_exchange_large_data_buffers_with_the_coprocessor_-_principle

Now, I want to know the way that exchange large data from Cortex-A7 to Cortex-M4 by using DDR.

I especially want to know how to read data on DDR from Cortex-M4.​

I would be grateful if there is any sample source code.

Is there any sample source code that transfer large data from Cortex-A to Cortex-M?

Best Regards,

H. Masuda

[Olivier GALLIEN]

Hi @HMasu.1​ 

The page you mention is coupled with the one containing sample source code :

https://wiki.st.com/stm32mpu-ecosystem-v1/wiki/How_to_exchange_large_data_buffers_with_the_coprocessor_-_example

You didn't notice it or it does not suit your need ?

Olivier

[HMasu.1]

Hi @Community member​ ,

Thank you for your reply.

I understand that the following wiki page describes the example that transfer large data from Cortex-M4 to Cortex-A7 by using DDR.

https://wiki.st.com/stm32mpu-ecosystem-v1/wiki/How_to_exchange_large_data_buffers_with_the_coprocessor_-_example

I want to know how to transfer large data from Cortex-A7 to Cortex-M4 by using DDR.

I especially want to know how to read data on DDR from Cortex-M4.​

Is there any sample source code that transfer large data from Cortex-A to Cortex-M?

Best Regards,

H. Masuda

[HMasu.1]

Hi @Community member (ST Employee)​ ,

I understand that Cortex-M4 program can not access DDR directly.

How can Cortex-M4 program receive large data in DDR from Cortex-A7?

Best Regards,

H. Masuda

[HMasu.1]

Hi @Community member​ ,

Is this thread's support over...?

I'm in trouble because sometimes I suddenly lose response in the middle of communication even in the other question.

I would be very grateful if you could support me.

Best Regards.

H. Masuda

[Olivier GALLIEN · Accepted solution]

Hi @HMasu.1​ ,

You may know that as per disclaimed in :

https://community.st.com/s/question/0D50X0000C0xW4jSQE/community-ground-rules-and-etiquette

"ST does not guarantee responses to every question posted in the community, yet we will provide programs and engagement to make the response rate and availability of useful content as high as possible"

If you need specific and dedicated support I invite you to contact your local ST sales office in order to setup a privilege link.

Then back to this post question.

No we do not provide on the shelve example from Cortex-A to Cortex-M but we consider that the provided example from Cortex-M to Cortex-A is a good based that can be modified without much obstacle to revert to data direction.

Olivier

[HMasu.1]

Hi @Community member​ ,

​Thank you for your response.

I understood the disclaimed of the community.

I'm sorry I misunderstood.

And I understood that this sample source code can help me to implement the source code that send large data from Cortex-A7 to Cortex-M4 with using DDR.

I will carefully analyze this sample source code.

Thank you.

H. Masuda