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Altera_Forum's avatar
Altera_Forum
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15 years ago

ADV7181B and Clocked input megacore function

Hello

could somebody help me?

I need to interface the adv7181B (with an YCbCr 4:2:2) with the Clocked Video Input function, but I have no idea about the settings I have to use.

I think that i need to load the PAL presets, but the output from the adv is 8bit wide, the CVI needs 10bit. I've tried to put the V_sync and H_sync on the same bus, but it doesn't seem to work.

Any hint, please?

8 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Currently, I set CVI as 8 bit and embedded sync format.

    I've set vid_datavalid as vcc, but all that i get is onle a black screen.

    So, i've tryed to set CVI as 8 bit and separate sync format, but still, using vid_datavalid as vcc it does't work.

    Output from the video conerter, in 4:2:2 YCbCr there are only

    TD_DATA[7..0]

    TD_HS

    TD_VS

    TD_RESET

    TD_CLOCK (@27MHz)

    I REALLY don't know how to interface them correctly with the CVI.

    Any hint wold be precious..
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    I think "Vid_datavalid" should be conncet to a pin that is low level when Vertical Blanking Interval,and hight when signal is valid.Just like PIN "RTS" in SAA7113.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    oh, thanls for your reply.

    Right now, I "resolved" that problem long time ago!
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    @Phate,

    May I ask how you have solved this problem? When I use the Test Pattern Generator (YCbCr, 8 bit, 4:2:2, Interlaced, Sequential) I get a correct image on the screen, so all the components between the generator and the VCO are correct. When I attach the TV Decoder, i just get a black (or grey) image, with a correct sync on the screen (well, most of the times).

    I use the following signals with embedded sync signals:

    TD_CLK

    TD_DATA

    TD_RESET

    vid_locked and vid_datavalid are tied to VCC. Is this correct?

    Any help would be appreciated!
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Hi,

    right now, I don't remember how I did; there should be a couple of posts in this forum where other users helped me. If I find them, I link them.

    Anyway, I should have sources at home.

    Phate.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Hi Phate,

    Thnx for your reply. I switched to the University Program cores, they just do the job perfect.