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Altera_Forum
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21 years ago

about component made by user logic

hello,

anyone encounter this problem that a component made by user logic can't run with nios system that has comprised ram and flash and so on?

who can give me some suggestion?

thank you!

21 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Thanks

    Sorry I omit another two user logics in my design. The following is the complete structure.

    i) Custom Logic I -> FIFO -> IUL (Read) - Nios - IUL (Write) -> FIFO -> Custom Logic II

    ii) Custome Logic III -> FIFO -> IUL (Read) - Nios

    iii) Custom Logic IV <- Memory <- IUL (Write) - Nios

    iv) A PLL provide a systme clk to such logic blocks respectively. They finished the information transmission thru FIFO.

    Custom Logic I/II/III are verified that they comply with the timing requirements. However, when Custom Logic IV is added, Custom Logic I/II/III can&#39;t work well. The result is not correct as before. Even Nios refuse to work. I slacken delay requirements between SRAM and Avalon so that Nios can work well now.

    I read the timing analyses. Only Custome IV have some critical paths which are not in the normal range. Need I add some timing constraints on such paths?