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Altera_Forum's avatar
Altera_Forum
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16 years ago

vga controller not working.

Hi,

I am a Ph.D. student at purdue university. I was planning on porting some video applications onto nios processor on DE2 board.

I am trying to setup VGA for these apps. I downloaded the video controller IP from

ftp://ftp.altera.com/up/pub/university_program_ip_cores/90/

video_out.zip.

I am using sram as a pixel buffer.

I am supplying 50MHz clock to all the components of the system.

and 25MHZ VGA_CLK.

My monitor always outputs "No Signal" . I am completely clueless about this. Can anyone help me on this?

Thanks,

Vinay.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I would suggest to take an oscilloscope and see if anything is getting out of the VGA connector first. It should help you find where the problem comes from. You can start with the horizontal and vertical sync signals.

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I am having the same difficulties, first of all recheck your design and make sure that the clock signals are exactly as described in the documentation of the vga in the doc folder under the university program path. If the clocks aren't configured correctly, the "ON" light on your screen shouldn't even light up when its connected to the board. After you have done that either 1: it will work, or 2: you will be stuck like I am. :D .

    After tracking down which function fails to execute through the IDE. I found

    my system gets stuck in the IOWR_32DIRECT command. which means that the Sram connection isn't working well. I am currently looking to see if the clock gets a -3ns shift as required in the sram spec and if maybe the vga_controller address space is protected in some way. If you solve your problem please inform me. Good hunting!

    Jonathan.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Anyone of You succeeded in making that vga controller working? Please share Your experiences...

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    hello faddi!

    check out this thread: 

    http://www.alteraforum.com/forum/showthread.php?t=20085

    I've posted some working code, that displays some garbage on the screen, but it's working and can be easly modyfied in NIOS IDE