Maybe some new technical information about the Yamaha YM2612
Moderator: BigEvilCorporation
Maybe some new technical information about the Yamaha YM2612
Hello SpritesMind... i'm new here... so sorry if i'm doing something wrong i just want to share a Japanese book that i found in the net a few days ago... here http://retrocdn.net/File:FM_TOWNS_JP_Te ... a_Book.pdf ... is a Technical Book for the FM TOWNS system... as you know this computer has the same YM2612 sound chip as the Mega Drive/Genesis... from pages 218 to 241 has a lot of technical information about the chip... i showed this to a person who has knowledge on Japanese language and the chip and that person assured me that the info in this book his better than the Sega Docs or the Yamaha YM2608 documentation...the book needs translation though ...I think someone should see this.Thanks for the attention...
Re: Maybe some new technical information about the Yamaha YM2612
I meant that it explains things better =P Actually has details about how all the values affect the sound instead of a quick overview (there are even tables indicating how long it takes for envelopes to go mute for every possible decay value). And actually explains how FM works (i.e. where the phase modulation is applied and how it's fed into each operator). It's absurdly in-depth as far as programming manuals go.
I don't think there's anything new though. Once the YM2612 got decapped pretty much everything was visible.
Sik is pronounced as "seek", not as "sick".
Re: Maybe some new technical information about the Yamaha YM2612
Oh... ok... I misinterpreted you ... sorry... now is better explained... thank you... It's a pity that it was not discovered earlier....
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Re: Maybe some new technical information about the Yamaha YM2612
Outside of telling how the phase modulation works and the tables there isn't anything new there. I does mention test registers explicitly though, but no extra info haha.
Values in the tables aren't very useful for MD though, because the YM runs at 8MHz there, so all the values are slightly too big. Sega docs also have the values based on 8MHz clock and not (53.203424 / 7) or (53.693175 / 7).
Values in the tables aren't very useful for MD though, because the YM runs at 8MHz there, so all the values are slightly too big. Sega docs also have the values based on 8MHz clock and not (53.203424 / 7) or (53.693175 / 7).
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
Re: Maybe some new technical information about the Yamaha YM2612
That's why I said "maybe"... i'm not a "Tech Guy" just a curious one... I just wanted to share this ... i hope it helps on something...
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Re: Maybe some new technical information about the Yamaha YM2612
It is definitely cool stuff, thänk you for digging it up ~
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
Re: Maybe some new technical information about the Yamaha YM2612
No need to thank me ... I was just lucky to find this.Those "Engrish" words on the page 218 "FM MODURATION" and "YM2612" caught my attention ...
Re: Maybe some new technical information about the Yamaha YM2612
I'm not even sure if the decay tables are really useful anyway since the durations specified in them only make sense when the decay starts from the peak (otherwise they last shorter). The other tables make more sense since they deal with frequency and the values are relative (e.g. how many cents are added).TmEE co.(TM) wrote: ↑Mon Jul 31, 2017 9:53 amOutside of telling how the phase modulation works and the tables there isn't anything new there. I does mention test registers explicitly though, but no extra info haha.
Values in the tables aren't very useful for MD though, because the YM runs at 8MHz there, so all the values are slightly too big. Sega docs also have the values based on 8MHz clock and not (53.203424 / 7) or (53.693175 / 7).
Still, I'd assume that the circuit used to compute all this is already visible from the decap shots, right?
Sik is pronounced as "seek", not as "sick".