Video Clocked output and VGA

Thanks for your answer.

I've managed to use text pattern and clocked output, no i can display color bars both in 1024*768 and 640*480.

Right now, I am trying to use the frame buffer between the test pattern generator and the clocked video output, using the sdram to store pixels.

I am not sure on wich clock should I use.

Now, I am in trouble with the frame buffer and clocks...

I am using (in 640*480) 31.5 MHz as pixel video clock, 100 MHz as test video, clocked output and frame buffer clock,finally, a 100Mhz with a -3ns delay for the SDRAM, but the system does not work. I have no DDR2 on the DE2 board, but I think that it shouldn't be necessary in order to use the FB with a 640*480 image.

Any hint?