382 lines
No EOL
7 KiB
C++
382 lines
No EOL
7 KiB
C++
/****************************************************************************
|
|
|
|
emu2149.c -- YM2149/AY-3-8910 emulator by Mitsutaka Okazaki 2001-2016
|
|
|
|
2001 04-28 : Version 1.00beta -- 1st Beta Release.
|
|
2001 08-14 : Version 1.10
|
|
2001 10-03 : Version 1.11 -- Added PSG_set_quality().
|
|
2002 03-02 : Version 1.12 -- Removed PSG_init & PSG_close.
|
|
2002 10-13 : Version 1.14 -- Fixed the envelope unit.
|
|
2003 09-19 : Version 1.15 -- Added PSG_setMask and PSG_toggleMask
|
|
2004 01-11 : Version 1.16 -- Fixed the envelope problem where the envelope
|
|
frequency register is written before key-on.
|
|
2015 12-13 : Version 1.17 -- Changed own integer types to C99 stdint.h types.
|
|
2016 09-06 : Version 1.20 -- Support per-channel output.
|
|
|
|
References:
|
|
psg.vhd -- 2000 written by Kazuhiro Tsujikawa.
|
|
s_fme7.c -- 1999,2000 written by Mamiya (NEZplug).
|
|
ay8910.c -- 1998-2001 Author unknown (MAME).
|
|
MSX-Datapack -- 1991 ASCII Corp.
|
|
AY-3-8910 data sheet
|
|
|
|
*****************************************************************************/
|
|
#include "stdafx.h"
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include "emu2149.h"
|
|
|
|
static uint32_t voltbl[2][32] = {
|
|
{0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x07, 0x09,
|
|
0x0B, 0x0D, 0x0F, 0x12,
|
|
0x16, 0x1A, 0x1F, 0x25, 0x2D, 0x35, 0x3F, 0x4C, 0x5A, 0x6A, 0x7F, 0x97,
|
|
0xB4, 0xD6, 0xFF, 0xFF},
|
|
{0x00, 0x00, 0x03, 0x03, 0x04, 0x04, 0x06, 0x06, 0x09, 0x09, 0x0D, 0x0D,
|
|
0x12, 0x12, 0x1D, 0x1D,
|
|
0x22, 0x22, 0x37, 0x37, 0x4D, 0x4D, 0x62, 0x62, 0x82, 0x82, 0xA6, 0xA6,
|
|
0xD0, 0xD0, 0xFF, 0xFF}
|
|
};
|
|
|
|
static uint8_t regmsk[16] = {
|
|
0xff, 0x0f, 0xff, 0x0f, 0xff, 0x0f, 0x1f, 0x3f,
|
|
0x1f, 0x1f, 0x1f, 0xff, 0xff, 0x0f, 0xff, 0xff
|
|
};
|
|
|
|
#define GETA_BITS 24
|
|
|
|
static void
|
|
internal_refresh(PSG* psg)
|
|
{
|
|
if (psg->quality)
|
|
{
|
|
psg->base_incr = 1 << GETA_BITS;
|
|
psg->realstep = (uint32_t)((1 << 31) / psg->rate);
|
|
psg->psgstep = (uint32_t)((1 << 31) / (psg->clk / 8));
|
|
psg->psgtime = 0;
|
|
}
|
|
else
|
|
{
|
|
psg->base_incr =
|
|
(uint32_t)((double)psg->clk * (1 << GETA_BITS) / (8 * psg->rate));
|
|
}
|
|
}
|
|
|
|
void
|
|
PSG_set_clock(PSG* psg, uint32_t c)
|
|
{
|
|
psg->clk = c;
|
|
internal_refresh(psg);
|
|
}
|
|
|
|
void
|
|
PSG_set_rate(PSG* psg, uint32_t r)
|
|
{
|
|
psg->rate = r ? r : 44100;
|
|
internal_refresh(psg);
|
|
}
|
|
|
|
void
|
|
PSG_set_quality(PSG* psg, uint32_t q)
|
|
{
|
|
psg->quality = q;
|
|
internal_refresh(psg);
|
|
}
|
|
|
|
PSG*
|
|
PSG_new(uint32_t c, uint32_t r)
|
|
{
|
|
PSG* psg;
|
|
|
|
psg = (PSG*)malloc(sizeof(PSG));
|
|
if (psg == NULL)
|
|
return NULL;
|
|
|
|
PSG_setVolumeMode(psg, EMU2149_VOL_DEFAULT);
|
|
psg->clk = c;
|
|
psg->rate = r ? r : 44100;
|
|
PSG_set_quality(psg, 0);
|
|
|
|
return psg;
|
|
}
|
|
|
|
void
|
|
PSG_setVolumeMode(PSG* psg, int type)
|
|
{
|
|
switch (type)
|
|
{
|
|
case 1:
|
|
psg->voltbl = voltbl[EMU2149_VOL_YM2149];
|
|
break;
|
|
case 2:
|
|
psg->voltbl = voltbl[EMU2149_VOL_AY_3_8910];
|
|
break;
|
|
default:
|
|
psg->voltbl = voltbl[EMU2149_VOL_DEFAULT];
|
|
break;
|
|
}
|
|
}
|
|
|
|
uint32_t
|
|
PSG_setMask(PSG* psg, uint32_t mask)
|
|
{
|
|
uint32_t ret = 0;
|
|
if (psg)
|
|
{
|
|
ret = psg->mask;
|
|
psg->mask = mask;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
uint32_t
|
|
PSG_toggleMask(PSG* psg, uint32_t mask)
|
|
{
|
|
uint32_t ret = 0;
|
|
if (psg)
|
|
{
|
|
ret = psg->mask;
|
|
psg->mask ^= mask;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void
|
|
PSG_reset(PSG* psg)
|
|
{
|
|
int i;
|
|
|
|
psg->base_count = 0;
|
|
|
|
for (i = 0; i < 3; i++)
|
|
{
|
|
psg->count[i] = 0x1000;
|
|
psg->freq[i] = 0;
|
|
psg->edge[i] = 0;
|
|
psg->volume[i] = 0;
|
|
psg->ch_out[i] = 0;
|
|
}
|
|
|
|
psg->mask = 0;
|
|
|
|
for (i = 0; i < 16; i++)
|
|
psg->reg[i] = 0;
|
|
psg->adr = 0;
|
|
|
|
psg->noise_seed = 0xffff;
|
|
psg->noise_count = 0x40;
|
|
psg->noise_freq = 0;
|
|
|
|
psg->env_volume = 0;
|
|
psg->env_ptr = 0;
|
|
psg->env_freq = 0;
|
|
psg->env_count = 0;
|
|
psg->env_pause = 1;
|
|
|
|
psg->out = 0;
|
|
|
|
}
|
|
|
|
void
|
|
PSG_delete(PSG* psg)
|
|
{
|
|
free(psg);
|
|
}
|
|
|
|
uint8_t
|
|
PSG_readIO(PSG* psg)
|
|
{
|
|
return (uint8_t)(psg->reg[psg->adr]);
|
|
}
|
|
|
|
uint8_t
|
|
PSG_readReg(PSG* psg, uint32_t reg)
|
|
{
|
|
return (uint8_t)(psg->reg[reg & 0x1f]);
|
|
|
|
}
|
|
|
|
void
|
|
PSG_writeIO(PSG* psg, uint32_t adr, uint32_t val)
|
|
{
|
|
if (adr & 1)
|
|
PSG_writeReg(psg, psg->adr, val);
|
|
else
|
|
psg->adr = val & 0x1f;
|
|
}
|
|
|
|
static inline void
|
|
update_output(PSG* psg)
|
|
{
|
|
|
|
int i, noise;
|
|
uint32_t incr;
|
|
|
|
psg->base_count += psg->base_incr;
|
|
incr = (psg->base_count >> GETA_BITS);
|
|
psg->base_count &= (1 << GETA_BITS) - 1;
|
|
|
|
/* Envelope */
|
|
psg->env_count += incr;
|
|
while (psg->env_count >= 0x10000 && psg->env_freq != 0)
|
|
{
|
|
if (!psg->env_pause)
|
|
{
|
|
if (psg->env_face)
|
|
psg->env_ptr = (psg->env_ptr + 1) & 0x3f;
|
|
else
|
|
psg->env_ptr = (psg->env_ptr + 0x3f) & 0x3f;
|
|
}
|
|
|
|
if (psg->env_ptr & 0x20) /* if carry or borrow */
|
|
{
|
|
if (psg->env_continue)
|
|
{
|
|
if (psg->env_alternate ^ psg->env_hold) psg->env_face ^= 1;
|
|
if (psg->env_hold) psg->env_pause = 1;
|
|
psg->env_ptr = psg->env_face ? 0 : 0x1f;
|
|
}
|
|
else
|
|
{
|
|
psg->env_pause = 1;
|
|
psg->env_ptr = 0;
|
|
}
|
|
}
|
|
|
|
psg->env_count -= psg->env_freq;
|
|
}
|
|
|
|
/* Noise */
|
|
psg->noise_count += incr;
|
|
if (psg->noise_count & 0x40)
|
|
{
|
|
if (psg->noise_seed & 1)
|
|
psg->noise_seed ^= 0x24000;
|
|
psg->noise_seed >>= 1;
|
|
psg->noise_count -= psg->noise_freq ? psg->noise_freq : (1 << 1);
|
|
}
|
|
noise = psg->noise_seed & 1;
|
|
|
|
/* Tone */
|
|
for (i = 0; i < 3; i++)
|
|
{
|
|
psg->count[i] += incr;
|
|
if (psg->count[i] & 0x1000)
|
|
{
|
|
if (psg->freq[i] > 1)
|
|
{
|
|
psg->edge[i] = !psg->edge[i];
|
|
psg->count[i] -= psg->freq[i];
|
|
}
|
|
else
|
|
{
|
|
psg->edge[i] = 1;
|
|
}
|
|
}
|
|
|
|
if (psg->mask & PSG_MASK_CH(i))
|
|
continue;
|
|
|
|
if ((psg->tmask[i] || psg->edge[i]) && (psg->nmask[i] || noise))
|
|
{
|
|
if (!(psg->volume[i] & 32))
|
|
psg->ch_out[i] += (psg->voltbl[psg->volume[i] & 31] << 4);
|
|
else
|
|
psg->ch_out[i] += (psg->voltbl[psg->env_ptr] << 4);
|
|
}
|
|
|
|
psg->ch_out[i] >>= 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
static inline int16_t
|
|
mix_output(PSG* psg) {
|
|
return (int16_t)(psg->out = psg->ch_out[0] + psg->ch_out[1] + psg->ch_out[2]);
|
|
}
|
|
|
|
int16_t
|
|
PSG_calc(PSG* psg)
|
|
{
|
|
if (!psg->quality) {
|
|
update_output(psg);
|
|
return mix_output(psg);
|
|
}
|
|
|
|
/* Simple rate converter */
|
|
while (psg->realstep > psg->psgtime)
|
|
{
|
|
psg->psgtime += psg->psgstep;
|
|
update_output(psg);
|
|
}
|
|
psg->psgtime = psg->psgtime - psg->realstep;
|
|
|
|
return mix_output(psg);
|
|
}
|
|
|
|
void
|
|
PSG_writeReg(PSG* psg, uint32_t reg, uint32_t val)
|
|
{
|
|
int c;
|
|
|
|
if (reg > 15) return;
|
|
|
|
val &= regmsk[reg];
|
|
|
|
psg->reg[reg] = (uint8_t)(val & 0xff);
|
|
switch (reg)
|
|
{
|
|
case 0:
|
|
case 2:
|
|
case 4:
|
|
case 1:
|
|
case 3:
|
|
case 5:
|
|
c = reg >> 1;
|
|
psg->freq[c] = ((psg->reg[c * 2 + 1] & 15) << 8) + psg->reg[c * 2];
|
|
break;
|
|
|
|
case 6:
|
|
psg->noise_freq = (val & 31) << 1;
|
|
break;
|
|
|
|
case 7:
|
|
psg->tmask[0] = (val & 1);
|
|
psg->tmask[1] = (val & 2);
|
|
psg->tmask[2] = (val & 4);
|
|
psg->nmask[0] = (val & 8);
|
|
psg->nmask[1] = (val & 16);
|
|
psg->nmask[2] = (val & 32);
|
|
break;
|
|
|
|
case 8:
|
|
case 9:
|
|
case 10:
|
|
psg->volume[reg - 8] = val << 1;
|
|
break;
|
|
|
|
case 11:
|
|
case 12:
|
|
psg->env_freq = (psg->reg[12] << 8) + psg->reg[11];
|
|
break;
|
|
|
|
case 13:
|
|
psg->env_continue = (val >> 3) & 1;
|
|
psg->env_attack = (val >> 2) & 1;
|
|
psg->env_alternate = (val >> 1) & 1;
|
|
psg->env_hold = val & 1;
|
|
psg->env_face = psg->env_attack;
|
|
psg->env_pause = 0;
|
|
psg->env_count = 0x10000 - psg->env_freq;
|
|
psg->env_ptr = psg->env_face ? 0 : 0x1f;
|
|
break;
|
|
|
|
case 14:
|
|
case 15:
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return;
|
|
} |