Posted By
Luca
on 2024-03-16
03:24:34
 |  Re: SD2IEC SID Player V2
You have noticed? Really? 
Ok, the situation is a little more complex than that, so let's recap.
Initially, in order to test the ReSeed, I used SD2IEC SID Player V2 playing Last Ninja 2 music, and the output went bad: channel 2 tended to vanish, the volume was in general very low, some Sustain/Release were weird.
But if you play Last Ninja 2 with any impromptu player which copies the $D400 registers to $FD40 at the end of the play call, the result is the same, as tested on YAPE. On the other side, playing it directly on the C64 registers at $D400 works the right way.
Ok, it's the classic case in which you can't simply copy $D400 to $FD40 because the player handles in several ways the registers within the same frame. This is what Solder has written in the 13th chapter of Signals 3 diskmagazine: they only way to prevent this, is to directly convert the SID file itself by intercepting every single call to the $D400 registers and shifting'em to the $FD40 base. Solder finishes the note writing that this direct method fully substitutes the simple $D400->$FD40 copy which had been initially used as player in the Synergy SIDcard Software suite which had been released embedded with the original hardware.
Good, so what's happened when I compared the usage of the ReSeed, which we have now definitively interpreted, with a C264's Audio Extension? Well, it plays perfect even using SD2IEC SID Player V2! And no, we're not in the C64 Legacy mode which reads at $D400! Why this happens? I would have expected the same result as for the ReSeed, but: no.
In the next hours, I'm gonna test the same both on the NST's Audio Extension V2.0 and the original Solder's SID Card (Newer). meanwhile, is there a reason for this oddity?
Ok, I did it, and actually it works
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