Street Fighter 2 Audio Problems

XianXi

Member
Joined
May 23, 2007
Messages
801
Reaction score
4
Location
Honolulu, Hawaii
Got a SF2 that I'm fixing for a friend.

Background music is perfectly normal, the analog channel is on the fritz to where is plays sounds randomly during attract and gameplay.

The A board uses a Z80 and YM2151 and an OKI6235 (I think, faded ss). I know the Z80 is good and the YM2151 so I am almost certain that it is the OKI as it is connected to one of the address lines on chip 19 and it just reads low.

Can anyone confirm that it is an OKI6235 and if it handles the analog (sound fx)?
 
The OKI does D/A conversions of whatever samples you have in ROMs. The ROMs are on the B board - the 2 1Mb chips next to the 512Kb chip that is the sound program ROM. Check traces/pins and board interconnects. Also make sure the 2 ROMs haven't been swapped.
 
It's an Oki m6295 chip.

And make sure the sound roms have the code for that SF rom set (date code on the boot up screen).

Mixing and matching sound files can do odd things.
 
Last edited:
Fixed.

Turns out Q0 and Q3 on 19 had corroded traces. Now only thing left to fix is a missing address/data line for tile data.
 
Back
Top Bottom