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Altera_Forum's avatar
Altera_Forum
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14 years ago

Overcloking SGDMA transfer using clock crossing bridge

Hi,

I am trying to increase data transfer rate of SGDMA using clock crossing bridge. Does anyone know how to connect them in SOPC builder??

I've successfully increased data transfer rate for DMA in the past. Attached picture shows the connection, but i have no idea how to do it with SGDMA, tried many different ways to do so.

Anyone who knows, please help!!

Thank you

Regards,

Michael

3 Replies

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

    It's pretty much the same thing when you use the SGDMA. It's hard to give an exact answer without knowing what you are trying to do. Inserting clock crossing bridges at random doesn't always have a positive result.

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

    I just want memory transfer from onchip RAM to SRAM to go faster than 50MB/s.

    I've tried putting clock crossing bridge between CPU and SGDMA and memories, but i dont get positive results, and sometimes no results at all. so i really need to know how and where to put this bridge.

    Michael
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    If that SRAM is not synchronous (not SSRAM) I wouldn't expect too much more performance out of it.

    Assuming you are using SSRAM then you would probably want the clock crossing bridge to be between the DMA masters and the on chip memory if you want to put the SSRAM and DMA on a different clock domain. This will make sure SOPC Builder doesn't insert a clock crossing adapter for you which only handles a read every 9 clock cycles approximately.