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Here's why you can't save a GBS in .spc format:

The Super Game Boy is considered a coprocessor on the Super NES, just like Super FX, SA-1, etc. Unlike some NSF players that support coprocessor sound in Famicom rips, the SPC players that I'm aware of do not support coprocessor sound.

tepples wrote:Here's why you can't save a GBS in .spc format:

The Super Game Boy is considered a coprocessor on the Super NES, just like Super FX, SA-1, etc. Unlike some NSF players that support coprocessor sound in Famicom rips, the SPC players that I'm aware of do not support coprocessor sound.

Heck, none support processor sound too AFAIK. All that's emulated is the APU. Hence no SPC rips of games that require the main CPU unit - Lost Vikings, FEDA, Furai no Shiren, a few more.

Is the Super Game Boy generating sound and pass it trought an audio pin into the SNES (?) or does it just give parameters to the SPC700 to emulate the GB sound ? As far I know there is no audio pin on the SNES conector, but maybe I'm wrong.

PS : Nonsensedubois lied one more time.

I would guess that the SGB sends some kind of gb-sound engine over to the spc-700 and then only sends commands over to this gb-sound thingy in the spc-700 through the I/O pins of the CPU. And then the sounds get generated in the spc-700.
Either that or everything is taken care of in the SNES CPU and then it just streams the sound over to the spc-700?

edit:
or maybe the SGB takes care of the sound and pass it on to the spc-700 through the cpu?

The hot point is that the SPC700 cannot create Square wave via normal samples, else they'll get filtered because of the cubit interpolation and will sound weird. I hate lowpass filtered NES/GB sound. I didn't use my super game boy since at least 2 years, so I should play it back to remember how it sounded.

SGB sound is identical to GB/GBC sound except faster and half a semitone higher pitched. This leads credence to either 1. sample compression hardware on the SGB along with DMA of compressed sample stream from the SGB through the CPU to the SPC or 2. Famicom style mapper sound.

This may very well be my final GBS request because of I'm leaving in about a week and I'll be back well I don't know. It's Pac-man special color edition, Pokemon Puzzle Challenge (I'm surprised this hasn't been ripped along with pokemon gold/silver because of popularity) Hoyle card games and Stargate. That's it. I'm also thinking of a Nsf requset but I won't post it here.

I finished replaying DK in gameboy mode, and what do you know, credits music.

Today, when I tried to add the track number into the playlist in the gbs, it played way too fast, and it lead me to discover a very beginner error I made... I set the timer interrupt speed wrong (exactly copying the byte from the debugger without masking out the bits that are unused. ), which actually made the entire gbs play at the wrong speed, so to compensate, I played around with the reload counter until the speed sounded right... yeah. So to fix this gbs, I masked out the unused bits in the control register, and set the reload value to what gets set in the game. For some reason, DK will change the reload value when it plays the credits song to make it play slower, and with the borked control byte I had, it made it play much too fast, so I think that's why I left it out of the gbs in the first place. Sorry about that.

You can get the updated gbs at my site. Sorry if I neglected to tackle this issue sooner. :S

tepples wrote:SGB sound is identical to GB/GBC sound except faster and half a semitone higher pitched. This leads credence to either 1. sample compression hardware on the SGB along with DMA of compressed sample stream from the SGB through the CPU to the SPC or 2. Famicom style mapper sound.

The Game Boy core of the SGB runs the CPU and refresh faster than a standard Game Boy (61.17? Hz with the CPU speeded up proportionately), which explains the pitch difference, but that doesn't change your main argument. I'm not an expert on the SGB, so I don't mean to argue anything.
I would like to correct one detail in another post:

Bregalad wrote:...else they'll get filtered because of the cubit (sic) interpolation and will sound weird.

Gaussian interpolation, not cubic interpolation.

Really ? I've heard that Gaussian was an approximate workaround and that Cubic was the actual interpolation.
Or did I mix up and remembered it the wrong way arround ?

I am pretty darn sure that the SGB-CPU just passes its audio along the 2 audio-in pins on the cartridge connector of the SNES.

ccovell wrote:I am pretty darn sure that the SGB-CPU just passes its audio along the 2 audio-in pins on the cartridge connector of the SNES.

yeah I recently read about the audio pins on the cartridge connector. didn't know they exist before.

ccovell wrote:I am pretty darn sure that the SGB-CPU just passes its audio along the 2 audio-in pins on the cartridge connector of the SNES.

I agree, since that makes a lot of sense.

The SGB does send commands to the SPC700, but only for real SNES-generated sound (not for the main Game Boy sound).

So that means the SNES mix audio from the SPC700's DSP output and the cartridge connector to send it to the output ?
Then the SNES does also allow carts with their own synthetizer just like the NES, but none wanted to do that because the SPC700 was powerfull enough... ?

In addition, Nintendo controlled all Game Pak manufacturing on the Super Famicom, unlike the Famicom.