Re: [hatari-devel] HATARI sound.c questions

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 21/05/2019 à 21:00, Arnaud Carré a écrit :
> Hi,
>
> First of all, awesome work for HATARI. Emulating so many atari machines 
> is challenging (including ST wakeup state, etc).
>
> Reading a thread from 
> http://www.atari-forum.com/viewtopic.php?f=16&t=36792 I browsed sound.c 
> and find many similar things with YM2149 of SainT emulator. I know 
> HATARI use plenty of code form different authors. As I didn't saw any 
> ref to SainT or StSound in https://hatari.tuxfamily.org/doc/authors.txt 
> I wonder if StSound inspired sound.c long time ago or has nothing to do 
> with it?
>
> cheers
>
> Arnaud

Salut leonard !

Nice to have you on the Hatari mailing list.

If I remember correctly, it's possible you sent me some code from saint 
or stsound regarding sound emulation and also the trick of emulating 
cpu/mfp clocks by using the 31333 / 9600 ratio.

If you look into cycInt.c and sound.c,you will see that you're credited 
there, it seems I forgot to add you in author/thanks.txt file.

But regarding sound emulation, this code of yours is not used anymore, I 
rewrote the YM emulation after doing some high freq recording of my real 
STF to precisely measure how counters are internally 
incremented/decremented (in fact they're decremented) and I use a much 
more accurate engine that fully emulates the 250000 cycles per second as 
a real YM does and then downsample this 250 kHz to the chosen output 
freq on the PC.

Nicolas