PowerPak SPC player issues

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Ramsis
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PowerPak SPC player issues

Post by Ramsis »

These have lurked in my firmware ever since its initial beta-1 release, and I finally want to get rid of 'em. :wink:

1. Some older (?) SPCs, mainly from SquareSoft games, only play with echo-like artifacts right at the beginning. I made a short video to show what I mean exactly: http://manuloewe.de/snestuff/temp/spc.flv

I should mention that the SPC uploader used is blargg's, just like what sd2snes uses (and where I stole the code from, actually :P ). I've already tried tweaking the timing by relocating some buffer vars from/to the direct page, but to no avail. I also tried to revert to the latest version of mic_'s uploader at some point, which I could only get to play the very first note or chord of any given song, and then freeze. Tell you what, the exact same artifacts could still be heard. :|

2. Occasionally, SPCs won't play at all (e.g. 01:36 in the video). I do clear the RDNMI flag before re-enabling NMI and IRQ after the upload procedure has completed, in case that matters.

Needless to say, neither of these issues occurs on sd2snes.

Here's the code: SPC player / SPC uploading routines

Thanks for any helpful input on this! :)
Some of my projects:
Furry RPG!
Unofficial SNES PowerPak firmware
(See my GitHub profile for more)
User avatar
Ramsis
Posts: 341
Joined: Sun Jul 01, 2012 6:44 am
Location: Lion's den :3
Contact:

Re: PowerPak SPC player issues

Post by Ramsis »

Anyone, please ...? :|
Some of my projects:
Furry RPG!
Unofficial SNES PowerPak firmware
(See my GitHub profile for more)
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