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Swapping in DDRAM3

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  • Swapping in DDRAM3

    Hi Robert Feranec,
    Can you make a video about swapping in DDRAM? I don't understood more about swapping, can you help me?

  • #2
    Hi Khai, I put it on my todo list For now, read this document, that will help you (page 42):

    Click image for larger version

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    Don't forget. It is very important that you use the correct DQS and DQM signals for the specific data byte. That is especially important when you decide to swap the whole bytes - together with the DATA byte, you have to move also DQS and DQM signals.

    For example:

    - Let's say, you have data group with signals DQ0-DQ7,DQS0, DQM0. For bit swapping, based on the note above you can not move DQ0, DQS, DQM, but you can swap signals DQ1-DQ7 between them

    - If you have groups DQ0-DQ7,DQS0, DQM0 and DQ8-DQ15,DQS1, DQM1, you can swap them, but you have to swap the groups completely (all the signals)

    For swapping, there is a build in feature in Altium, but normally I just simply move the nets in schematic and re-synchronize the PCB.


    • #3
      It's very helpful for me.
      Thanks Robert.