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Altera_Forum's avatar
Altera_Forum
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15 years ago

Help: Writing into CVO registers

My system consists of only TPG , CVO and SD-SDI output.

TPG (720x480)>> CVO >> SD SDI output

Using Neo, I can read/write the TPG correctly, but each time

when I try to write into the VCO the software hung.

Does this mean I have to do something on TPG (i.e stop) or put into certain operating mode before I can write into any of the VCO registers ? My goal is I want to be able to change VCO parameters at runtime and view the changes of video image on SDI monitor.

Thanks in advance.

3 Replies

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

    You should be able to read/write the CVO registers at any time without hanging the system. The only thing I can think of is that maybe you selected the a wrong/bad clock in SOPC builder for the CVO.

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

    Thanks, Kevin. I will check.

    Since I can read/write the TPG fine, I would think my clock (27MHZ) should be fine.

    Question for you though: At the moment I am only interested in using MODE1 of the CVO, the following two parameters were what I set on the megawizard that I am not very certain about !

    Runtime configurable video modes = 1

    Width of "vid_std" bus = 1

    Are these setting correct?

    Again thank you for your help,

    JIMMY
  • CSoil's avatar
    CSoil
    Icon for New Contributor rankNew Contributor
    7 years ago

    Hi Jimmy, did you ever figure out your issue? I am having issues with the CVO not getting the mode matched.