First post... so I will just roughly introduce myself.
My name is Brendan, and I am a Mechanical Engineer by nature... but lately I have had a growing interest in electronics. I have now recently modded my Sega Saturn, and now I'm hooked!
However, I have very very little experience... and to be honest, I don't really know what the hell I am doing... but I am trying to use common logic with my ideas.
Now this one problem has me stuck now quite nicly. I am in the process of eliminating all ground loops in my A/V theatre set up. I tried transformers, isolating cables, devices and other do-dads... and to no satisfactory results... until I tried Toslink SPDIF. It just sounds amazing... crisp and clean as one would expect.
Now I am now trying to get the best audio out of my Sega Megadrive. I currently have a model 2 but i would like a model 1 with a megacd1 and (somehow) inbuilt 32x.
Now the problem this presents are many. As you guys know, the system as a whole will output 3 sets of audio sources, one for each system... And that getting a digital signal out of YM2612 is impossible.
I then did a little bit of research and stumbled on some information on this forum and others... http://nfggames.com/forum2/index.php?topic=3719.0
This lead me to make a post on Racketboy.com as follows:
I made contact with a member named Tiido Priimägi... asking for his advice.has anyone used this chip: "Yamaha YM2608" as apposed to the "Yamaha YM2612" to be coupled with another sound processing chip to output spdif?
since it doesn't have an internal DAC, it might be possible... however, I am not sure...
I plan to use the sega megadrive version 1. I will isolate the sound processing chip: YM2612
And then using a multipole double throw switch to connect up YM2608 through the 6 normal FM channels and leave the remaining 10 channels open (not connected to anything)
http://nemesis.hacking-cult.org/MegaDri ... slated.PDF
And then using the digital OPO sound output from YM2608 to input into CS8406
http://pdf1.alldatasheet.com/datasheet- ... S8406.html
And then using the spdif output to send the signal to a toslink transmitter.
If the output from YM2608 fits the serial input into CS8406, then i cant see any reason why it cant work??? I am not sure about the output of the serial audio bit clock and word clock.
I am also looking into the possibility of CS8416 and other chips from cirrus logic though im doubting that they will be compatible :S
Please tell me what you think.
And what he says is very true.This will not work because the YM2608 is not fully software compatiblewith YM2612, all games using the DAC channel will not have PCM samplesounds. I don't think the output is something other DACs can handlebesides Yamaha's own. I do think its far easier to use an ADC+morechips to get SPDIF out of MD.....also you cannot leave the input pins on the 2608 unused, they mustbe tied to either ground or VCC.
So I have then been looking into ADC directly from YM2612, however, I then stumbled upon another issue... Perhaps you guys can see it.
So I am now wondering which circuit I should be using if I am coupling cs5361 and cs8406 from Cirrus Logic.
Another issue I am getting worried about is lag being introduced if I now have 2 more sound processing chips and a complex audio filtering circuit.
So I am posting here... if anyone can help me or give me a little more guidance... as this stuff is such on a crazy advanced level that I am not used to.
Thanks very much for your time in reading my essay.