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/*
* petsound.c - implementation of PET sound code
*
* Written by
* Teemu Rantanen (tvr@cs.hut.fi)
*
* This file is part of VICE, the Versatile Commodore Emulator.
* See README for copyright notice.
*
* 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., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307 USA.
*
*/
#include <stdio.h>
#include "vice.h"
#include <math.h>
#include "petsound.h"
#include "maincpu.h"
#include "sound.h"
#include "utils.h"
struct sound_s
{
int on;
CLOCK t;
BYTE sample;
double b;
double bs;
int speed;
int cycles_per_sec;
};
static warn_t *pwarn;
static BYTE snddata[4];
/* XXX: this is not correct */
static WORD pet_makesample(double s, double e, BYTE sample)
{
double v;
int sc, ec, sf, ef, i, nr;
sc = ceil(s);
sf = floor(s);
ec = ceil(e);
ef = floor(e);
nr = 0;
for (i = sc; i < ef; i++)
if (sample & (1 << (i%8)))
nr++;
v = nr;
if (sample & (1 << (sf % 8)))
v += sc - s;
if (sample & (1 << (ef % 8)))
v += e - ef;
return v * 4095.0 / (e-s);
}
int sound_machine_calculate_samples(sound_t *psid, SWORD *pbuf, int nr)
{
int i;
WORD v = 0;
#if 0
{
char *t = " ";
warn(pwarn, 4,
"Sound support for PET is at _very_ experimental stage.\n"
"%sIf you think this doesn't sound right, please wait\n"
"%sfor the next snapshot or help me get this right.\n"
"%s //tvr", t, t, t);
}
#endif
for (i = 0; i < nr; i++)
{
if (psid->on)
v = pet_makesample(psid->b, psid->b + psid->bs, psid->sample);
pbuf[i] = v;
psid->b += psid->bs;
while (psid->b >= 8.0)
psid->b -= 8.0;
}
return 0;
}
void sound_machine_init(void)
{
pwarn = warn_init("SOUNDPET", 128);
}
sound_t *sound_machine_open(int speed, int cycles_per_sec)
{
sound_t *psid;
int i;
psid = xmalloc(sizeof(*psid));
memset(psid, 0, sizeof(psid));
psid->speed = speed;
psid->cycles_per_sec = cycles_per_sec;
if (!psid->t)
psid->t = 32;
psid->b = 0.0;
psid->bs = (double)psid->cycles_per_sec/(psid->t*psid->speed);
snddata[0] = 0;
snddata[1] = 0;
snddata[2] = 4;
snddata[3] = 0;
for (i = 0; i < 4; i++)
sound_machine_store(psid, i, snddata[i]);
return psid;
}
void sound_machine_close(sound_t *psid)
{
free(psid);
}
void store_petsnd_onoff(int value)
{
snddata[0] = value;
sound_store(0, snddata[0]);
}
void store_petsnd_rate(CLOCK t)
{
snddata[2] = t & 0xff;
snddata[3] = (t >> 8) & 0xff;
sound_store(2, snddata[2]);
sound_store(3, snddata[3]);
}
void store_petsnd_sample(BYTE sample)
{
snddata[1] = sample;
sound_store(1, snddata[1]);
}
void sound_machine_store(sound_t *psid, ADDRESS addr, BYTE val)
{
switch (addr)
{
case 0:
psid->on = val;
break;
case 1:
psid->sample = val;
while (psid->b >= 1.0)
psid->b -= 1.0;
break;
case 2:
psid->t = val;
break;
case 3:
psid->t = (psid->t & 0xff) | (val << 8);
psid->bs = (double)psid->cycles_per_sec/(psid->t*psid->speed);
break;
default:
abort();
}
}
void petsnd_reset(void)
{
store_petsnd_onoff(0);
sound_prevent_clk_overflow(clk);
}
BYTE sound_machine_read(sound_t *psid, ADDRESS addr)
{
abort();
return 0;
}
void sound_machine_prevent_clk_overflow(sound_t *psid, CLOCK sub)
{
}
char *sound_machine_dump_state(sound_t *psid)
{
char buf[256];
sprintf(buf, "on=%d sample=%d rate=%d\n", psid->on, psid->sample, psid->t);
return stralloc(buf);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.