Project2612 Forums

Hi everyone,

Some of you may know of my work making hardware VGM player in my YMK YM2612 (OPN2), and YM3438 (OPN2C) synthesizer.

I don't know what was on me that I never thought of posting about this before, anyway, there are a few packs that have hardware incompatibility, a fact that became highlighted when Nuked OPN2 core started being used in VGM players. This issue was also reported in this thread.

I had already seen this issue on my hardware VGM player, but initially I thought it was due to my code having bugs on access timing to the chip. However, eventually I noticed that the same issues I had were present when I switched my in_vgm plugin to using Nuked OPN2 core, which I had heard before in my hardware vgm player. It took me many months to make the connection (sorry) but basically the MAME YM2612/YM3438 emulator allows some glitches to get passed, and therefore VGM loggers never knew the problem existed.

Nuked OPN2 core is set to output sound as in the YM2612, and since MAME OPN2 core normally outputs sound more like the OPN2C, I gave it a shot on the YM3438 as well, but the sound glitches are the same on either chip. So conclusion, the issues are with the VGMs themselves.

We can update this list as I find new sets or people report:

Sets mostly or completely unplayable:
-Rocket Knight Adventures

Sets with issues in some tracks:
-Rolling Thunder 2

Sets with undesirable noises at track start:
-Sonic 3
-Shining Force II

Unfortunately that means that these sets most likely need re-logging. If anyone wants recordings of how these tracks sound, I can provide them but get ready for major ear pain.

There are several sets which have issues, some of them do illegal register writes, other initialize all registers at once, etc.

Bear in mind also that the speed (and, as a consequence, the pitch) is wrong and needs adjustments.

Try Comix Zone and you'll see what I mean.