Oops, I post it at the wrong place this morning.
I'm confused when something like this occurs, I've posted it in the Hardware section instead of the NESdev one.
I've done a little code working on MMC5 to test scanline waiting/timing and it should be tested on a real NES.
So here is the link :
http://nesdev.parodius.com/cgi-bin/wwwthreads/showpost.pl?Board=hardware&Number=1049&page=0&view=collapsed&sb=5

Long live to Chrono Trigger !