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Can I use an YMZ284 instead if I connect:

PRG A13 to A0
(NOT PRG_CE) NAND PRG_A14 to /CE (/CE goes low when PRG /CE is low AND PRG A14 is high)
PRG R/W to /WR

...and everything else like the previous versions? I'm new to this cart hacking stuff.

Thanks

Yes, I did exactly that and it works. Interestingly, R/W doesn't really work on this chip and it is not possible to read it, so there will never be bus conflicts with reads with this chip.

Beware: the output is quite weak and is only able to source current; it can't sink current.

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((λ (x) (x x)) (λ (x) (x x)))

Thank you very much! Maybe I can use one of the NAND-gates (74HC02) to form a NOT-gate and use a feedback resistor to use it as a crude amplifier to save a chip? Nintendo used that trick to amplify the sound output of the 2A03. Probably I should just use an op-amp, but I like "elegant" solutions.

That's how the ORIGINAL game works so I don't see why that wouldn't work.

Edit: I think it has to be HCU type though ...

I think the 74HC will work just fine. Sure, HCU's are more linear and work from rail to rail, but for beeps and bloops it should work just fine(?) I will test it.

EDIT:
The famicom uses a 74HC368 for its sound.

HC won't work because it "won't oscillate"... I mean it won't amplify anything. I tried some and it didn't go well. Nintendo used HCU for a reason and I understood when I tried to mimic their circuit. Well try it and let us know how it goes !

http://www.fairchildsemi.com/an/AN/AN-88.pdf

Not very linear indeed, but it should work. I don't have the parts yet.

Hi, all!
What do you think about this schematic with YMZ284 sound?

Anybody???

Lacks an amplifier. Even if the logic is fine the sound will be too low on volume.

Amplifier is not a problem. Logic is important...

Did you try building that ? I never tried that particular chip. I did try the GI AY-3-8910 and YM2149. Nothing else. The logic would be different depending on how the enable works for your chip.

I was under the impression a clock divider wasn't needed? If you look at the data sheet you can see a clock divider in the block diagram. Can someone spread some light on this?

I did not need any when I used the YM2149. AY-3-8910 did require it.

Neither the 8910 nor the 2149 is self sufficient, but they're each lacking different things.

AY-3-8910: You must add a clock divider since it doesn't have one built in. However it's output doesn't require an amplifier.
YM2149: Has built in clock divider, but has a weak output so you have to add an amplifier.

Both require the same address decoder.

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If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers