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Altera_Forum's avatar
Altera_Forum
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15 years ago

interfacing with avalon streaming protocol

Hi all.

I need some hints about interfacing with avalon video-ST protocol.

I am making a video system that should elaborate video data between two VIP megacores fuction.

to test my systems, I am using test pattern generator, YCrCb 4:2:2 8bit per color plane in parallel, in my custom blok I need to handle separately Y and Cb.

How can I work ONLY on video data pakets, without modifing control pakets and stalling all my video system?

Are there any megacore functions or streaming adapters that could help me?

or anyone could give me some hint please?

2 Replies

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

    The first startofpacket where the lower 4 bits of the input data field are 0 is the beginning of your video packet. All data after this condition until the endofpacket is asserted are your valid video samples. All you need to do is look for this condition to begin your processing.

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

    thanks for your answer.

    The problem is that there are others signals in Avalon-ST like the "ready" that I Don't know how to handle.

    I mean, i made this simple module (http://alteraforum.com/forum/showthread.php?t=23187) using registers, but it seems to not work properly until I set a latency of 3 for both avalon sink and avalon source..

    I would like to mantain my personal video streaming block sink and source latency to 1, like other megacore functions.