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Altera_Forum
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12 years ago

Digitize RGB video using DE0-Nano

Hi all, I'm building a 15Khz RGB to VGA converter using the DE0-Nano, to be used with old computers from the 80's. I know there are some boards in the market like GBS8200 but I'm not happy with...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

You won't be able to use HSYNC to directly sync your PLL.

I assume (with your current implementation) you are adjusting the outgoing data, by a full clock cycle, every time you detect a 'change' to the incoming HSYNC pulse timing.

You need to 'hide' these timing changes in the VSYNC inter frame gap - the dead time between frames. Providing you deliver a full frame of video without adjusting your outgoing data and HSYNC timing your jitter should disappear.

Cheers,

Alex