I think I saw that formula somewhere actually. Can you step me through it?
I have added to the linker flag as you suggested. My output is not garbled. It seems to scroll normally too.
Understood about ramtiles, they come first in the array and that each value in the vram array points to either a flash or ram tile by tile number.
Collision detection. I would like to compare the x and y coordinates for a character sprite against adjoining tiles in vram. If that tile number is, say, the road or a bridge then I want to let the character walk over it. Otherwise I want to block the movement. Think of it as creating a sort of whitelist for tiles that can be traversed by a sprite. This has been my goal this weekend. I've learned a whole lot but haven't made much progress, until now I think. Once I figure out that formula you gave us.Out of curiosity, what's the reason you need a "GetTile()" function in your game? If it has potential for reuse I could just add one in mode 3.
I can handle sprite to sprite detection by using bounding boxes or just plain distance, once I get to that point and understand what that means.
CunningFellow, thank you for your offer. If I can use that formula then I should be good for the time being. Perhaps I can take a raincheck for the future?