Hello renaudberube!
Thx for your reply! I found out what was wrong - I made some terrible mistake while adding sdram to my project (used output instead of bidirectional pin). Now everything is working like a charm :) Anyway many thx for your concern :)
Regards
@speak48
Probably you pixel buffer device has different name in your sopc system, maybe "pixel_buffer_0" or something like that...
Many people have problems with this VGA stuff, so I attached some basic project including pixel buffer and simple software that draws some garbage on the screen. Hope some of You will find that useful. Project is for DE-2 board