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Altera_Forum's avatar
Altera_Forum
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15 years ago

DDR HP Controller with Bursts

Hello All,

Having an application with NIOSII, DDR HP Controller and others, all are running the same ddr_sysclk at 133MHz. Using Quartus8.1, CycloneIII and the basic application works with single accesses to DDR. Now we are trying to use the DDR burst capability in order to get over the Latency time. We'we tried a Avalon Pipline Bridge with bursts enabled with no success, the reads and writes to succesive addresses are still dispatched as single accesses. Does anybody have expirience in using bursts???? Our DDR is a single 16 bit device and all accesses from NIOS are 32bit.

Thanks

MKopo

2 Replies

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

    The NIOS will only perform bursting when

    1 - Bursting is enabled on its bus masters

    2 - Data access is performed via the cache.

    The pipeline bridge will only add latency. If you don't need it to meet timing requirements, remove it.

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

    use Q9.1. The new HPCII controller will group transactions to create bursts automatically, so there is no need to enable bursts on the processor or sopc builder side.

    --dalon