→ jeff0811:又解決了一個謎團，這些天才真是造福人類 12/17 13:50
http://mamedev.emulab.it/kale/?p=1271
Even deeper inside two smoking barrels
Irem M107 HW, a driver that indeed didn’t received much love in his life.
The driver was a complete mess, with completely broken World PK Soccer, Dream
Soccer ’94 with huge slowdowns and Fire Barrel … well, it was marked as
working but imho it wasn’t really working, with that layer covering half the
screen and completely missing sound, effectively making it a painful
experience to play. After some study at the code, I’ve realized that the
driver was continously triggering an unmapped line from the main CPU,
directly correlated to some sound response r/w. Easy fix, that’s a reset
line directly connected to the sound CPU.
Then the graphics. After some study at the code me and Haze realized that
current rowscroll handling was entirely wrong, since that rowscroll is
enabled thru a completely different bit (used by World PK Soccer gameplay) …
we studied some videos of the real PCB floating around the net and realized
it was actually enabling row select, a kind of effect also used in this game
for stretching the tilemap in the vertical axis (effectively doing some
pseudo zooming).
Fire Barrel
http://www.youtube.com/watch?v=nJM85xbmHKU&feature=player_embedded
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