Now that 18 Holes Pro Golf is in a much better shape (needs that somebody would like to decrypt the original version to get it fully working), I’ve moved my attention to Pro Soccer.  Surprisingly, the main issue is that this one uses some sort of protection involving gfx addresses that are scrambled thanks to 1+ PAL(s). I’ve started to compare it with the Cassette version, and got some results:

As you can see from snap 4, work isn’t yet 100% complete, plus this version is not 1:1 compatible with the cassette one (some gfxs addresses are different). But for sure, this descrambling work is just more time consuming rather than requiring programming skills… 😉

EDIT: noticed that actually the game uses dynamic tiles instead of the aforementioned PAL descramble guess. Weird but possible…

EDIT2: Fixed the Goal Keeper screen, the tilemap was using a vram mirror for the banking. Game promoted to working now.

I’ve convinced myself in looking the three GNW “Dec0 Pro” games series (a.k.a. 18 Holes Pro Golf, Pro Sport and Pro Soccer). The game with the worst condition was 18 Holes Pro Golf, so I’ve started to look at it for first. It’s basically a nightmare, with a background layer and a tilemap/bitmap framebuffer hybrid mess, with “tilemap cells” that are written to the resulting screen as-is, without any tilemap hook-up for it as you might expect…

And now the bad news: it has issues with the main program (for example hazards doesn’t do anything), that might be caused by a bad rom or a slightly bad decryption (service mode returns “rom bad error 6″ as well).