AN427 Video Sample Design for VGA

First, thanks for your prompt response to my first ever forum posting.

I'm using the Cyclone III Video Kit (from BItec), which expects 12-bit multiplexed RGB and which seems to use both edges of the video clock to drive its video output chip. I've tried to come up with a hybrid sytem based on the Altera Video reference design (which has DVI o/p) but but adapted to VGA by looking at the reference design that comes with the Bitec Kit (which doesn't use the Avalon clocked output component, just loads of VHDL).

The suggested thread is helpful to give me increased confidence in getting the right parameter settings for the clocked output, but there are still too many unknowns and I still can't quite get it working (eg required clock rate - I'm using 25MHz). I think I might have to refer this to the Bitec people.