appeared to be a bad dump, a good dump works fineSangokushi III - Romance of the Three Kingdoms (hangs at Sega logo)
needed SUB-CPU sync before triggering the level 2 interrupt from MAIN-CPU sideEarnest Evans (hangs after Wolf Team logo)
Seirei Shinseiki - Fhey Area (hangs after Wolf Team logo)
were fixed by improving MAIN-CPU polling loop detection, i solved the issue by clearing CPU polling detection flag every time a "DBF" instruction is executed: it appeared that successive readings of the same register were stopping the CPU when they should only have been done a dozen time in a row. Reducing needed cycle gap between two successive read for polling detection would not help: it makes other sensitive games hang since CPU sync is highly tied to MAIN-CPU being stopped on polling loop. So it was tight but it now works for every sync-sensitive games.i'm problably a spammer International Soccer (hangs after Sega logo)
Jeopardy (hangs during intro)
NHL '94 (hangs after intro)
Seima Densetsu 3x3 Eyes (hangs after Sega logo)
gfx errors in the former where fixed by having Word-RAM state being maintaned on mode switchingESPN Sunday Night NFL (hangs when starting new game + gfx errors during intro)
NFL Football Trivia Challenge (hangs when starting a game)
game not starting were because i didn't noticed you needed to use 2nd player controller to go further
were apparently fixed by some of the above changes, though I'm not sure which onesCorpse Killer (random "drive error" hangs during game)
Joe Montana's NFL Football (hangs when starting a game)
i do not know exactly why, on real hardware, when doing DMA from Word-RAM, setting the source address one word above the wanted address solves the VDP "slow" read-out problem but instead of simply decrementing the source address in VDP register, I handle it by dismissing the first read: VDP address is incremented and DMA length decremented but no word is written to VDP and source address is not incremented. It's a little bit different from what Gens/Picodrive are doing (i think).Battle Frenzy / Blood Shot (graphic issues)
Chuck Rock (corrupted tiles)
Ecco the Dolphin (random corrupted tiles)
Ecco: The Tides of Time (random corrupted tiles)
World Cup USA 94 (corrupted tiles)
Anyway, those games do not use an auto-increment of 2 like most other games and I was not taking care of this properly, they were fixed by properly using the auto-increment register when dismissing this first read
expects the TOC to be correct and especially, play some audio track and expects the track index to increment itself up to some point before continuing so if track lengths are not correct, you can get stuck.A-Rank Thunder Tanjouhen (hangs during intro cinematic )
was fixed by improving SUB-CPU polling detection for some undetected cases where the same register was indeed read twice in a loop at two different PC locationsCosmic Fantasy Stories
In the end, this leaves out only two remaining games with graphical bugs:
Adventures of Willy Beamish, The (gfx error in the first logo)
AH3 Thunderstrike / Thunderhawk (gfx errors in radar window, low-half is corrupt)
and about that again
I somehow broke it when experimenting with CDD latency: it appears that it requires at least one interrupt delay before effectively reading data after a PLAY command is sent. It seems like you should always apply at least one interrupt delay when a PLAY command is sent, no matter what is LBA offset or drive status since the drive was already in PLAY "status" when this PLAY command is sent.Is Radical Rex working for you, Eke? Never got that one running (neither did Gens at that time), I did some research into it but don't really remember anything (it has been some years)..