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Altera_Forum's avatar
Altera_Forum
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14 years ago

VIP Clocked Video Output- MODES

I'm using the Clocked Video Output (CVO) core from the VIP (Video and Image Processing) suite

on Altera Cyclone III video development card with Bitec HSMC DVI input/output daughtercard to display

a mixed video (non interlaced) on a DVI monitor.

I want the CVO modes to display different output resolutions:1280x1024, 1024x768 and 800x600

The default mode configured in the QSYS hardware is for 1024x768 resolution.

The way I configure the modes is: set mode invalid, write registers, stop CVO, set mode valid, start CVO.

When I run this and ask for the "Video Mode Matched" register I get "0" with a 1024x768 input and it displays the image.

But after changing the input I get the different modes from "Video Mode Matched" but I don't get any image and the display enters into sleep mode.

So, my questions are...

Where can I find all those video parameters, in case i'm not adding them correctly?

Are there any examples which uses different output modes?

Is there another possible error in my design?

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    I went through the examples but I couldn't find any example of run-time configuration for the CVO. The timing table is useful, but now I'm confused with the different Pclk MHz frequencies. I'm using a constant frequency of 100MHz for the CVO, how should I interpret these values then?

    Thank you
  • Altera_Forum's avatar
    Altera_Forum
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    See this I share it with you. It is the timing from one of the docments

  • Altera_Forum's avatar
    Altera_Forum
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    Anyway, I've used different parameters but the problem is I get no output at all, my display enters sleep mode whenever I change the system video input. The CVO status bit is always 0 after writing the GO bit.

    I also have a mixer with a TPG and a frame read from memory so I change the TPG resolution to the new one every time it changes after checking if the CVI is stable and has a valid resolution.