Color is up and running!
I had a lot of problems with instability. Sometimes a build worked, I then changed some small detail and it stopped working. The synthesizer says it should work up to 115MHz and I ran it at 100MHz. Should be OK. But when I went down to 90MHz the problems seemed to stop. Now it seems stable.
Just a few strange problems left. When a sprite is half outside the screen to the right some red pixels show up to the left, outside the picture. Should be impossible. Very strange. 🙂 A color seems a bit off on the sprites as well. If you look you can see that the right white stripe on each sprite is thicker than the left one. It should be a black and a white stripe. Not two white. But I don’t see this problem on other sprite shapes. I have to investigate…
After that, if nothing else turns up, it’s time for some serious C and C++ coding to make use of it. 🙂