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/*
Fake86: A portable, open-source 8086 PC emulator.
Copyright (C)2010-2013 Mike Chambers
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
/* speaker.c: function to generate output samples for PC speaker emulation. */
#include "config.h"
#include <stdint.h>
#include "i8253.h"
#include "mutex.h"
extern struct i8253_s i8253;
extern uint64_t gensamplerate;
uint64_t speakerfullstep, speakerhalfstep, speakercurstep = 0;
int16_t speakerpos = 0;
int16_t speakergensample() {
int16_t speakervalue;
speakerfullstep = (uint64_t) ( (float) gensamplerate / (float) i8253.chanfreq[2]);
if (speakerfullstep < 2) speakerfullstep = 2;
speakerhalfstep = speakerfullstep >> 1;
if (speakercurstep < speakerhalfstep) {
speakervalue = 32;
}
else {
speakervalue = -32;
}
speakercurstep = (speakercurstep + 1) % speakerfullstep;
return (speakervalue);
}
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