MCUXpresso linker file and use for external memory

[samsaprunoff]

Good day All,

I have been using MCUXpresso with my iMXRT parts and always used the RT's parts internal RAM memory for my applications.  However, I have one project where I need more RAM and so I have attached an external SDRAM device.  That said, I am unsure what changes I need to make to the linker file to allow the external SDRAM to be available to my application while still maintaining the use of the RT's internal RAM.  Secondly, once the linker file has been changed, what does one need to do within the application code to ensure that any variables created are to be stored in the external SDRAM.  Historically I used to do this using pragmas with the old CodeWarrior software, but I am unsure how to do this with MCUExpresso.  That said, I thought I would ask the experts here on how how best to implement the above.

Thanks in advance!

Cheers

[samsaprunoff]

Good day All,

Just an update to my original question.  There is a great description on how to direct MCUX to place variables, etc in other parts of memory within the MCUXpresso User's Guide - Section 18 ...18.13 is where I found what I needed.

Cheers,

Sam

[Gavin_Jia · Accepted solution]

Hi @samsaprunoff ,

Hope you are doing well!

A detailed description of the way the RT series uses SDRAM is provided in this link: https://community.nxp.com/t5/Blog/Overview-of-using-the-MIMXRT1170-EVK-with-MCUXpresso-IDE/ba-p/1241..., it should help you.

Please refer to Chapter 14. Building and Debugging Projects for SDRAM

Best regards,
Gavin

[samsaprunoff]

Good day Gavin,

All is well on my side and I hope the same with you!

Thank you for your post and the link!  I will review and will post again if I have more questions.

Thanks again! 

Cheers, Sam