06:39 <cr1901_modern> Wb Foone... there was something I actually wanted to ask you relevant to this channel (or ISA cards- one of the two), but I unfortunately can not remember it for the life of me :(

06:39 <cr1901_modern> Guess it wasn't important

23:32 <KillaMaaki2> Started trying to dive into the internals of the YM3812 for the purposes of emulation. I've been using this doc for reference https://docs.google.com/document/d/18IGx18NQY_Q1PJVZ-bHywao9bhsDoAqoIn1rIm42nwo/edit

23:32 <KillaMaaki2> I've reproduced the exp and log-sin tables in C#, which was easy enough.

23:33 <KillaMaaki2> But I'm trying to figure out how the exp table is actually used.

23:35 <KillaMaaki2> The doc says you take the 8 least significant bits of the "input" (which, I'm assuming, is the output from the log-sin table?) and index the exp table, add 1024, and you get the significand, and then use the remaining upper bits of that input as the exponent.

23:37 <KillaMaaki2> Trying to cross reference this with the YM3014B DAC, which seems to take a 10-bit mantissa and 3-bit exponent. The 3014 seems to just feed the mantissa through a 10-bit DAC, then use the 3 bit exponent put through a 3 -> 7 decoder and input into an analog shift.

23:37 <KillaMaaki2> Or at least that's what the data sheet seems to be saying.

23:40 <KillaMaaki2> As far as I can tell, if I've retrieved the mantissa and exponent from that exp table operation, then the resulting value should be something like ( (mantissa/1024.0) * pow(2, -exponent) ).... right? But that doesn't seem to be giving results that look correct, though I cross-referenced my exp/significand results with a spreadsheet someone else posted.

23:40 <KillaMaaki2> I assume I'm just being dumb and completely misinterpreted something

23:45 <Lord_Nightmare> Foone: you forgot something: the smurfs nightmare is a gbc rerelease of the smurfs 3 for original gb

23:45 <Lord_Nightmare> so that's even more gfx to rip

23:45 <Lord_Nightmare> fortunately the gb->gbc porting of the smurfs nightmare barely used any of the gbc extra features like the second vram page except for the status bar iirc

23:46 <Lord_Nightmare> monster go go go (which i think the existing dump of is actually bad) was a pirate port of smurfs 3 to run on gbc, and was done incredibly poorly (the parallax ground is broken among other things)

23:47 <Lord_Nightmare> the dump we have of monster go go go is actually of a later cart version, the oldest version was just a smurfs 3 hack and had no gbc stuff bolted on at all

23:47 <Lord_Nightmare> these messages have been brought to you by "stuff i remember from 16 years ago when I worked on gnuboy"