Difference between DCD and XMCD formats

[Juozas]

Dear Forum,

Can someone explain the difference between DCD and XMCD data formats? Using MCUXpresso IDE with iMXRT1170-EVK, the IDE constantly generates both dcd.h and xmcd.h files.

I know that XMCD stands for eXternal Memory Configuration Data and DCD for Device Configuration Data, but for me it seems they overlap quite a bit. Is there any advantages of using XMCD format? We have a custom board with HyperFlash NOR, SDRAM and eMMC.

Regards,

[Juozas]

Thank you for the reply, @kerryzhou .
So both DCD and XMCD are purely imxrt1170 BootROM features? XMCD is newer and easier format and DCD is older format (register dump), is that correct? Are there any performance differences comparing DCD and XMCD?

[kerryzhou]

Hi @Juozas ,

  You are always welcome!

  Yes, both DCD and XMCD is the BootROM features.

  XMCD is newer and easier format and DCD is older format!

   No performance difference, as totally the same configuration, just to the XMCD, ROM do more things, to let the customer code more simple.

Wish it helps you!

If you still have question about it, please kindly let me know.

If your question is solved, please help me to fill the feedback as resolved, thanks.

Any new issues, welcome to create the new question post, thanks.

Best Regards,

Kerry

[kerryzhou · Accepted solution]

Hi @Juozas ,

  Thank you for your interest in the NXP MIMXRT product, I would like to provide service for you.

  Both DCD and XMCD can be used to configure the SEMC for the SDRAM.

 DCD will configure the register value one by one.

 XMCD is the new method, you don't need like the DCD to configure each register, you just need to configure the related header, then the ROM will help you do a lot of thinks to configure the external memory.

 Anyway, you just need to use one, if you use DCD, don't need XMCD, if use XMCD, no need DCD.

You can use :

XIP_BOOT_HEADER_DCD_ENABLE
or
XIP_BOOT_HEADER_XMCD_ENABLE

to select it.

I also have write 2 ppt pages about it.

Wish it helps you!

If you still have question about it, please kindly let me know.

If your question is solved, please help me to mark the correct answer, just to close this case, thanks.

Any new issues, welcome to create the new question post, thanks.

Best Regards,

kerry