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matt's mind

^ is (theoretically) very doable, the design was oriented towards this.  access to the source is the hurdle, as you noted...

DDS output goes to the 'breakout header', so you can send the audio wherever you want.  controlling it is the big part, having it done ROM-side is very possible if there is support from the developer.

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matt's mind

or, (just thinking out loud), breakout circuits which could do EVEN MORE

sorry for the crappy looking board, it was pre-cleaning, during testing, i just happen to have had the pic handy for the editing atm

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Abandoned on Fire
kitsch wrote:

(i posted some updates weeks ago, they didn't bump the thread, no one noticed, but some news is worth the bumping so imma do it now)

pay particular attention to a link in the 'CPLD' section.

Yeah, completely slipped by me!  These are some very interesting details.

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Dallas, Texas

While I don't know how hard it was to actually create that extra sound channel (You're prolly a genius wizard), but I'm a tiny bit disappointed to find out there's no filter. The one thing IMO the GameBoy and NES are missing is some awesome filter action. (LSDj soft filters don't count tongue)

Bravo for an amazing and intriguing looking cart opportunity. I can't want to see this cart in action.

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Cleveland, OH
kitsch wrote:

-- CPLD --

Altera Max II

an interesting feature of kk_gb_8m is its ability to provide another channel of sound via an onboard monophonic Direct Digital Synthesizer (DDS).   

here are the specifications for controlling the DDS. 

recordings soon!

So.. I need a special version of LSDJ for this? wink

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matt's mind

as of now, lsdj doesn't support it, and if it did yeah it'd be a special rom to support this hardware.  or else a feature which could be hidden unless this cart was used, or just a null effect without it.  something like that. 

but, really, any developer could support this.  hopefully as straightforwardly as they'd do the other 4 (at least the goal was to make it somewhat easily integrative (strange word, i mean 'integrate-able'))

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Unsubscribe

Well give one free to Johan or Trash80 (or both) and see what magic happens big_smile

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matt's mind

johan wasn't interested, hadn't considered trash80 but thats a wonderful idea!

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Abandoned on Fire

Also nitro2k, maybe he'd do a weekly project on it.

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matt's mind

yup, in touch with nitro2k01, excellent thought too...  he actually has been a big (and kind) help in one particular area on the cart... 

thanks guys!

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Just curious - what is the progress with this cart?

Specifically, is it at the point where there are some recordings, even drone tones we can listen to? smile
Super excited for this.

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matt's mind

nearly done!

still have programming/testing to do after they are assembled, but its just about time.

recordings: i've actually got some made!  the tunes were created directly in the CPLD (rather than controlled by a ROM), i'll upload some sample code for one of the songs too.  i've done christmas tunes and a michael jackson song.

i'll try to get those gathered up and linked to asap.

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Toronto, Ontario, Canada

I'd love to buy one of these once they're ready to try out. I recently had to write a little Game Boy sound routine and I've been thinking of making it open source and adding support for this would be really easy given your documentation.

Any eta for an earliest beta version?

Last edited by jefftheworld (Jul 31, 2013 1:50 pm)

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matt's mind

eta: fingers crossed i'm thinking in < 2 weeks now.  the assembly took a little longer than anticipated, the unknown variable right now is the amount of troubleshooting i'll need to do to get these programmed and tested and wrapped up completely. 

there is always something tongue 

as soon as possible, basically.  to where its not rushed and compromises the quality of the product. 

and glad the docs seem like they'll be enough!  if you do take this on, and find there is info missing or whatever, PLEASE let me know i'd be happy to update it.  i think its enough for most everyone to add support for the 5th channel though (as long as the address range isn't already being used). 

if you pipe the 5th channel's sound through the gameboy, check out this part of pandocs too: http://nocash.emubase.de/pandocs.htm#so … lregisters

^ this link should take you to the Sound Control Registers section, not the bottom.  so, if it doesn't take you there, reload the page.  mine messed up on me and reloading it took me to the right part

(the header on kk_gb_8m is there so you can send the new audio wherever.  straight to its own mono jack, back into the game cart (and to the cart edge), or whatever you want.  its not hardwired to the cart edge, its available in the breakout header to do with what people wish)

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Toronto, Ontario, Canada

Yeah, I have a crib sheet with the game boy registers and that's part of my excitement here. It's a feature that I've always wanted to use!

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Abandoned on Fire

Hey I see there's a "regulated 5V" on the breakout header.  Is that something that can be controlled by a rom and is it ac coupled?  I'm sure you can see where I'm going with this...