If you don't have it, download FCEUX and Castlevania 3 (could probably use CV1, I didn't check). Run the game and get to stage 1. Now open the hex editor and view the PPU RAM. Scroll down to address $3F00 (near the very bottom). Highlight everything from $3F00 to $3F1F (so the first two lines) and paste these numbers in:
0F1D2D3D0F1D3D2D0F1D2D3D0F2D1D3D0F08003 70F0800100F0806100F081710
Might give some of you some ideas for a new game.
By the way, as soon as you change rooms, you'll have to do it all over again, but it only happens when changing rooms so not much to worry about until then.