Hi all,
My Donpachi plays music and sound effects just fine but has lost the 'layer' with the explosions/speech etc. Does anyone know where on the board that is generated so I can narrow down my search for issues? I mainly repair older classic era games so the lack of a schematic as well as my unfamiliarity with Cave board layout in general is hurting me here. Thanks in advance.
Donpachi losing certain audio
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system11
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Re: Donpachi losing certain audio
Check the analogue output of both OKI chips, one plays the music, one plays the effects, trace from there. It'll be quickly obvious which one is music, for the other if you see nothing on the chip then it's logic (or OKI) related, if you see the effects on a scope it's time to trace the audio path, op-amp would be a potential culprit.
http://www.ec66.com/market/sheet/msm6295.pdf
http://www.ec66.com/market/sheet/msm6295.pdf
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http://blog.system11.org
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hanasu
- Posts: 129
- Joined: Fri Nov 29, 2013 7:24 pm
Re: Donpachi losing certain audio
Thanks, will take a look.system11 wrote:Check the analogue output of both OKI chips, one plays the music, one plays the effects, trace from there. It'll be quickly obvious which one is music, for the other if you see nothing on the chip then it's logic (or OKI) related, if you see the effects on a scope it's time to trace the audio path, op-amp would be a potential culprit.
http://www.ec66.com/market/sheet/msm6295.pdf
