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Altera_Forum's avatar
Altera_Forum
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17 years ago

DDR2 Controller controlling 4-chips

Hello, I am new to using the DDR2 Megacore Controller and have a quick question. I have a board that has 4 DDR2 memories and has created 2-banks of memory each bank has 2-DDR2 memories. Each memory is 16-bits wide making each bank 32-bits. I would like to access the full 64-bits, could I achieve that by using a DDR2 MegaCore Controller with the data width 64-bits?

I was thinking that I might have to use 2-DDR2 MegaCore controllers each 32bits.

I've include a schematic how the DDR2 is configured.

Thank you very much,

joe

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    If the two banks are intended to operate independantly, either different addresses or R/W direction, you need two separate controllers, if they are working fully parallel, you can use a single controller with double data width.

    P.S.: My above answer is wrong regarding your hardware. The two banks could be operated from one controller only if they would share the address and control pins. There is no option in the controller IP to split these signals to two physical pins. So you have to use two controller instances in any case.
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Hello, thank you very much for taking the time to answer my post. Looking over the documentation I see it states "two independent banks of 64Mx32 words of ddr2 sdram". So I must use 2-controllers.

    That shouldn't be a problem or difficultly should it?

    thanks,

    joe
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    No problem at all. Just create two seperate controllers using the megawizard. If you're using Stratix II GX, I recommend using the new High-Performance DDR2 core as it may save you some headaches. However, the regular DDR2 core works fine as long as you configure everything appropriately.

    Jake