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aamodini's avatar
aamodini
Icon for New Contributor rankNew Contributor
1 year ago

Transfer Data from Nios II to FPGA using Avalon-ST

I am trying to transfer a chunk of data from Nios II to the FPGA fabric using the Avalon Streaming interface, and am facing a couple of challenges in implementing the same.

1. I'm unable to connect almost_full and almost_empty signals to the sink.

2. Are the driver APIs same as those available for Avalon FIFO Memory IP? If yes, how do we write data to the FIFO and read from it using Avalon-ST? I am unable to generate in_csr base address.

Board Debug
Fpga Devkit

5 Replies

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor
    1 year ago

    1) Not sure why you want to connect these status signals to the sink (which sink?). They are single bit Avalon streaming status signals that indicate when the FIFO is above or below the thresholds you've set, which is accessible via CSR access: https://www.intel.com/content/www/us/en/docs/programmable/683130/24-1/register-description-68335.html

    2) This is Avalon streaming, not memory-mapped, so there would be no API. You would control whatever component drives data into the FIFO (another source component). I don't think NIOS has a streaming option (I could be wrong on that; and FYI you should be looking at NIOS V since NIOS II is basically discontinued at this point) so I'm not sure why you are looking at this FIFO instead of a memory-mapped FIFO.

  • aamodini's avatar
    aamodini
    Icon for New Contributor rankNew Contributor
    1 year ago

    1. I see two warnings on the Platform Designer that say almost_full and almost_empty signals must be connected to an Avalon-ST sink (as seen in the first image attached). Hence I was just wondering if they should be connected.

    2. Does it mean I would just write to the FIFO just as I would in the case of a simple array/buffer?

    Oh I wasn't aware NIOS doesn't support streaming. Is there a documentation that says so?

    Thanks for the inputs!

  • tehjingy_Altera's avatar
    tehjingy_Altera
    Icon for Regular Contributor rankRegular Contributor
    1 year ago

    Hi


    We sincerely apologize for the inconvenience caused by the delay in addressing your Forum queries. Due to an unexpected back-end issue in our system, your Forum cases, along with others, did not get through as intended. As a result, we have a backlog of cases that we are currently working through one by one.

    Please be assured that we are doing everything we can to resolve this issue as quickly as possible. However, this process will take some time, and we kindly ask for your patience and understanding during this period. The cases will be attended by AE shortly.

    We appreciate your patience and understanding, and we are committed to providing you with the best support possible.

    Thank you for your understanding.


    Back to your issue, niosII only supports Avalon MM interface and not Avalon Stream Interface.

    You could not connect them together.


    Regards

    Jingyang, Teh


    Regards

    Jingyang, Teh


  • tehjingy_Altera's avatar
    tehjingy_Altera
    Icon for Regular Contributor rankRegular Contributor
    1 year ago

    Hi


    Do you have anymore follow up question on this case?


    Regards

    Jingyang, Teh


  • tehjingy_Altera's avatar
    tehjingy_Altera
    Icon for Regular Contributor rankRegular Contributor
    1 year ago

    Hi


    As we do not receive any response from you on the previous question/reply/answer that we have provided. Please login to ‘https://supporttickets.intel.com/s/?language=en_US’, view details of the desire request, and post a feed/response within the next 15 days to allow me to continue to support you. After 15 days, this thread will be transitioned to community support. The community users will be able to help you on your follow-up questions.


    Regards

    Jingyang, Teh