Sonic 3 stuck sound under waterfall

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dink
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Sonic 3 stuck sound under waterfall

Post by dink » Sat Jul 22, 2017 4:01 am

Hi all,
In Sonic 3 / first stage - after going past the 2nd loop, then go downward there is some water with a waterfall in the middle. When Sonic falls into the water, no problem - but when it goes under the waterfall, all sound emulation stops, and there's a hung fm note slowly decaying while he's there. As soon as Sonic goes past underneath the waterfall or jumps out of the water, the music continues. I've been trying to fix this emulation bug for ages it seems, and well, it still confuses me.
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Hopefully someone has run into this one before :) Sound in every other game is just fine.

best regards,
- dink

Natsumi
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Re: Sonic 3 stuck sound under waterfall

Post by Natsumi » Sat Jul 22, 2017 6:42 am

I am guessing you mean you are making a custom emulator and having this issue? No, I've never seen this happen, not on hardware nor any emulators. It is probably a timing related issue, like h-ints which are stopping Z80 for a few scanlines, which could cause issues... I would definitely see what happens during the h-int handler to see if there are any issues there. Maybe Z80 isn't reset properly somehow? Hard to tell with not much details given

dink
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Re: Sonic 3 stuck sound under waterfall

Post by dink » Sat Jul 22, 2017 10:07 pm

Thanks for the "hints" :) I re-ordered the syncing of z80 cpu in my frame and the problem is gone!

best regards & thanks,
- dink

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