Well, most of the time, we have two kinds of sound drivers on the Sega Genesis:
1- 68k-based driver, that handle the FM and PSG channels, and run a mini-driver on Z80 to play and handle the DAC channel. And yes, this is the driver that takes that high 68k CPU percentage I mentioned earlier. The pro of it is a higher possiblity of DAC sample rate (because Z80 process is very light and clean), and better versatility, especially considering it doesn't need any kind of ROM padding at all.
2- Z80-based driver, that handle the full sound process, FM, PSG and DAC outside the 68k, almost always at the cost of some sample rate. The pro of it is that 68k gets totally free of the sound process, so I get an extra chunk of RAM available, and I can take approach of those extra cycles for other more tasks without dropping frames.
For my game, I have changed to a Z80-based driver. This could me allow to achieve more "fancy" stuff without lagging, maybe more objects on the screen, more screen effects, and such. With C2 I'd have to revert to the 68k driver; and although the 68k is clocked to work on a higher speed, I can't avoid feeling a bit more nervous about this. Effects that use the Horizontal Interrupt are very likely to break upon the slightest lag, for example.
Edited by CrazyMonkey (02/16/16 10:54 PM)
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