ShuriZma
/
BizHawk
mirror of https://github.com/TASEmulators/BizHawk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
BizHawk/waterbox/pcfx/pce_psg/pce_psg.cpp

822 lines
20 KiB
C++
Raw Blame History

/* Mednafen - Multi-system Emulator
*
* Original skeleton write handler and PSG structure definition:
* Copyright (C) 2001 Charles MacDonald
*
* 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 "../defs.h"
#include "pce_psg.h"
#include <math.h>
#include <string.h>
// Frequency cache cutoff optimization threshold (<= FREQC7M_COT)
#define FREQC7M_COT 0x7 //0xA
void PCE_PSG::SetVolume(double new_volume)
{
for(int vl = 0; vl < 32; vl++)
{
double flub = 1.0 * new_volume * 8 / 6;
if(vl)
flub /= pow(2, (double)1 / 4 * vl); // ~1.5dB reduction per increment of vl
if(vl == 0x1F)
flub = 0;
for(int samp = 0; samp < 32; samp++)
{
int eff_samp;
if(revision == REVISION_HUC6280)
eff_samp = samp * 2;
else
eff_samp = samp * 2 - 0x1F;
dbtable[vl][samp] = (int32)(flub * eff_samp * 128); // * 256);
dbtable_volonly[vl] = (int32)(flub * 65536);
// dbtable[vl][samp] = (int32)(flub * eff_samp * 128);
// dbtable_volonly[vl] = (int32)(flub * 65536);
}
}
}
// Note: Changing the 0x1F(not that there should be) would require changing the channel pseudo-off volume check logic later on.
static const int scale_tab[] =
{
0x00, 0x03, 0x05, 0x07, 0x09, 0x0B, 0x0D, 0x0F,
0x10, 0x13, 0x15, 0x17, 0x19, 0x1B, 0x1D, 0x1F
};
#define CLOCK_LFSR(lfsr) { unsigned int newbit = ((lfsr >> 0) ^ (lfsr >> 1) ^ (lfsr >> 11) ^ (lfsr >> 12) ^ (lfsr >> 17)) & 1; lfsr = (lfsr >> 1) | (newbit << 17); }
static const int16 Phase_Filter[2][7] =
{
/* 0 */ { 35, 250, 579, 641, 425, 112, 6 }, // 2048
/* 1 */ { 6, 112, 425, 641, 579, 250, 35 }, // 2048
};
INLINE void PCE_PSG::UpdateOutputSub(const int32 timestamp, psg_channel *ch, const int32 samp0, const int32 samp1)
{
int32 delta[2];
delta[0] = samp0 - ch->blip_prev_samp[0];
delta[1] = samp1 - ch->blip_prev_samp[1];
const int16* c = Phase_Filter[(timestamp >> 1) & 1];
const int32 l = (timestamp >> 2) & 0xFFFF;
HRBufs[0][l + 0] += delta[0] * c[0];
HRBufs[0][l + 1] += delta[0] * c[1];
HRBufs[0][l + 2] += delta[0] * c[2];
HRBufs[0][l + 3] += delta[0] * c[3];
HRBufs[0][l + 4] += delta[0] * c[4];
HRBufs[0][l + 5] += delta[0] * c[5];
HRBufs[0][l + 6] += delta[0] * c[6];
HRBufs[1][l + 0] += delta[1] * c[0];
HRBufs[1][l + 1] += delta[1] * c[1];
HRBufs[1][l + 2] += delta[1] * c[2];
HRBufs[1][l + 3] += delta[1] * c[3];
HRBufs[1][l + 4] += delta[1] * c[4];
HRBufs[1][l + 5] += delta[1] * c[5];
HRBufs[1][l + 6] += delta[1] * c[6];
ch->blip_prev_samp[0] = samp0;
ch->blip_prev_samp[1] = samp1;
}
void PCE_PSG::UpdateOutput_Norm(const int32 timestamp, psg_channel *ch)
{
int sv = ch->dda;
UpdateOutputSub(timestamp, ch, dbtable[ch->vl[0]][sv],
dbtable[ch->vl[1]][sv]);
}
void PCE_PSG::UpdateOutput_Noise(const int32 timestamp, psg_channel *ch)
{
int sv = ((ch->lfsr & 1) << 5) - (ch->lfsr & 1); //(ch->lfsr & 0x1) ? 0x1F : 0;
UpdateOutputSub(timestamp, ch, dbtable[ch->vl[0]][sv],
dbtable[ch->vl[1]][sv]);
}
void PCE_PSG::UpdateOutput_Off(const int32 timestamp, psg_channel *ch)
{
UpdateOutputSub(timestamp, ch, 0, 0);
}
void PCE_PSG::UpdateOutput_Accum_HuC6280A(const int32 timestamp, psg_channel *ch)
{
int32 samp[2];
// 31(5-bit max) * 32 samples = 992
// 992 / 2 = 496
//
// 8 + 5 = 13
// 13 - 12 = 1
samp[0] = ((int32)dbtable_volonly[ch->vl[0]] * ((int32)ch->samp_accum - 496)) >> (8 + 5);
samp[1] = ((int32)dbtable_volonly[ch->vl[1]] * ((int32)ch->samp_accum - 496)) >> (8 + 5);
UpdateOutputSub(timestamp, ch, samp[0], samp[1]);
}
void PCE_PSG::UpdateOutput_Accum_HuC6280(const int32 timestamp, psg_channel *ch)
{
int32 samp[2];
samp[0] = ((int32)dbtable_volonly[ch->vl[0]] * (int32)ch->samp_accum) >> (8 + 5);
samp[1] = ((int32)dbtable_volonly[ch->vl[1]] * (int32)ch->samp_accum) >> (8 + 5);
UpdateOutputSub(timestamp, ch, samp[0], samp[1]);
}
// This function should always be called after RecalcFreqCache() (it's not called from RecalcFreqCache to avoid redundant code)
void PCE_PSG::RecalcUOFunc(int chnum)
{
psg_channel *ch = &channel[chnum];
//printf("UO Update: %d, %02x\n", chnum, ch->control);
if((revision != REVISION_HUC6280 && !(ch->control & 0xC0)) || (revision == REVISION_HUC6280 && !(ch->control & 0x80)))
ch->UpdateOutput = &PCE_PSG::UpdateOutput_Off;
else if(ch->noisectrl & ch->control & 0x80)
ch->UpdateOutput = &PCE_PSG::UpdateOutput_Noise;
// If the control for the channel is in waveform play mode, and the (real) playback frequency is too high, and the channel is either not the LFO modulator channel or
// if the LFO trigger bit(which halts the LFO modulator channel's waveform incrementing when set) is clear
else if((ch->control & 0xC0) == 0x80 && ch->freq_cache <= FREQC7M_COT && (chnum != 1 || !(lfoctrl & 0x80)) )
ch->UpdateOutput = UpdateOutput_Accum;
else
ch->UpdateOutput = &PCE_PSG::UpdateOutput_Norm;
}
void PCE_PSG::RecalcFreqCache(int chnum)
{
psg_channel *ch = &channel[chnum];
if(chnum == 0 && (lfoctrl & 0x03))
{
const uint32 shift = (((lfoctrl & 0x3) - 1) << 1);
uint8 la = channel[1].dda;
uint32 tmp_freq = (ch->frequency + ((uint32)(la - 0x10) << shift)) & 0xFFF;
ch->freq_cache = (tmp_freq ? tmp_freq : 4096) << 1;
}
else
{
ch->freq_cache = (ch->frequency ? ch->frequency : 4096) << 1;
if(chnum == 1 && (lfoctrl & 0x03))
ch->freq_cache *= lfofreq ? lfofreq : 256;
}
}
void PCE_PSG::RecalcNoiseFreqCache(int chnum)
{
psg_channel *ch = &channel[chnum];
int32 freq = 0x1F - (ch->noisectrl & 0x1F);
if(!freq)
freq = 0x20;
else
freq <<= 6;
freq <<= 1;
ch->noise_freq_cache = freq;
}
void PCE_PSG::PeekWave(const unsigned int ch, uint32 Address, uint32 Length, uint8 *Buffer)
{
assert(ch <= 5);
while(Length--)
{
Address &= 0x1F;
*Buffer = channel[ch].waveform[Address];
Address++;
Buffer++;
}
}
void PCE_PSG::PokeWave(const unsigned int ch, uint32 Address, uint32 Length, const uint8 *Buffer)
{
assert(ch <= 5);
while(Length--)
{
Address &= 0x1F;
channel[ch].samp_accum -= channel[ch].waveform[Address];
channel[ch].waveform[Address] = *Buffer & 0x1F;
channel[ch].samp_accum += channel[ch].waveform[Address];
Address++;
Buffer++;
}
}
uint32 PCE_PSG::GetRegister(const unsigned int id, char *special, const uint32 special_len)
{
uint32 value = 0xDEADBEEF;
const int ch = (id >> 8) & 0xF;
switch(id & 0xF0FF)
{
default: break;
case PSG_GSREG_SELECT:
value = select;
break;
case PSG_GSREG_GBALANCE:
value = globalbalance;
break;
case PSG_GSREG_LFOFREQ:
value = lfofreq;
break;
case PSG_GSREG_LFOCTRL:
value = lfoctrl;
break;
case PSG_GSREG_CH0_FREQ:
value = channel[ch].frequency;
break;
case PSG_GSREG_CH0_CTRL:
value = channel[ch].control;
break;
case PSG_GSREG_CH0_BALANCE:
value = channel[ch].balance;
break;
case PSG_GSREG_CH0_WINDEX:
value = channel[ch].waveform_index;
break;
case PSG_GSREG_CH0_SCACHE:
value = channel[ch].dda;
break;
case PSG_GSREG_CH0_NCTRL:
value = channel[ch].noisectrl;
break;
case PSG_GSREG_CH0_LFSR:
value = channel[ch].lfsr & 0x3FFFF;
break;
}
return(value);
}
void PCE_PSG::SetRegister(const unsigned int id, const uint32 value)
{
const int ch = (id >> 8) & 0xF;
switch(id & 0xF0FF)
{
default: break;
case PSG_GSREG_SELECT:
select = value & 0x07;
break;
case PSG_GSREG_GBALANCE:
globalbalance = value & 0xFF;
break;
case PSG_GSREG_LFOFREQ:
lfofreq = value & 0xFF;
break;
case PSG_GSREG_LFOCTRL:
lfoctrl = value & 0x83;
RecalcFreqCache(0);
RecalcUOFunc(0);
RecalcFreqCache(1);
RecalcUOFunc(1);
break;
case PSG_GSREG_CH0_FREQ:
channel[ch].frequency = value & 0xFFF;
RecalcFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_CTRL:
channel[ch].control = value & 0xFF;
RecalcFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_BALANCE:
channel[ch].balance = value & 0xFF;
break;
case PSG_GSREG_CH0_WINDEX:
channel[ch].waveform_index = value & 0x1F;
break;
case PSG_GSREG_CH0_SCACHE:
channel[ch].dda = value & 0x1F;
break;
case PSG_GSREG_CH0_NCTRL:
channel[ch].noisectrl = value & 0xFF;
RecalcNoiseFreqCache(ch);
RecalcUOFunc(ch);
break;
case PSG_GSREG_CH0_LFSR:
channel[ch].lfsr = value & 0x3FFFF;
break;
}
}
#if 0
void PSG_SetRegister(const unsigned int id, const uint32 value)
{
if(name == "Select")
PSG_Write(0x00, V);
else if(name == "GBalance")
PSG_Write(0x01, V);
else if(name == "LFOFreq")
{
PSG_Write(0x08, V);
}
else if(name == "LFOCtrl")
PSG_Write(0x09, V);
else if(!strncmp(name.c_str(), "CH", 2))
{
unsigned int psg_sel_save = select;
int ch = name[2] - '0';
char moomoo[64];
strncpy(moomoo, name.c_str() + 3, 63);
PSG_Write(0x00, ch);
if(!strcmp(moomoo, "Freq"))
{
PSG_Write(0x02, V);
PSG_Write(0x03, V >> 8);
}
else if(!strcmp(moomoo, "Ctrl"))
PSG_Write(0x04, V);
else if(!strcmp(moomoo, "Balance"))
PSG_Write(0x05, V);
else if(!strcmp(moomoo, "WIndex"))
psg.channel[ch].waveform_index = V & 0x1F;
else if(!strcmp(moomoo, "SCache"))
psg.channel[ch].dda = V & 0x1F;
else if(!strcmp(moomoo, "NCtrl") && ch < 4)
psg.channel[ch].noisectrl = V;
else if(!strcmp(moomoo, "LFSR") && ch < 4)
psg.channel[ch].lfsr = V & 0x3FFFF;
PSG_Write(0x00, psg_sel_save);
}
}
#endif
PCE_PSG::PCE_PSG(int32* hr_l, int32* hr_r, int want_revision)
{
//printf("Test: %u, %u\n", sizeof(psg_channel), (uint8*)&channel[0].balance - (uint8*)&channel[0].waveform[0]);
revision = want_revision;
switch(revision)
{
default:
abort();
break;
case REVISION_HUC6280:
UpdateOutput_Accum = &PCE_PSG::UpdateOutput_Accum_HuC6280;
break;
case REVISION_HUC6280A:
UpdateOutput_Accum = &PCE_PSG::UpdateOutput_Accum_HuC6280A;
break;
}
HRBufs[0] = hr_l;
HRBufs[1] = hr_r;
lastts = 0;
for(int ch = 0; ch < 6; ch++)
{
channel[ch].blip_prev_samp[0] = 0;
channel[ch].blip_prev_samp[1] = 0;
channel[ch].lastts = 0;
}
SetVolume(1.0); // Will build dbtable in the process.
Power(0);
}
PCE_PSG::~PCE_PSG()
{
}
int32 PCE_PSG::GetVL(const int chnum, const int lr)
{
psg_channel *ch = &channel[chnum];
const int gbal = 0x1F - scale_tab[(globalbalance >> (lr ? 0 : 4)) & 0xF];
const int bal = 0x1F - scale_tab[(ch->balance >> (lr ? 0 : 4)) & 0xF];
const int al = 0x1F - (ch->control & 0x1F);
int vol_reduction;
vol_reduction = gbal + bal + al;
if(vol_reduction > 0x1F)
vol_reduction = 0x1F;
return(vol_reduction);
}
void PCE_PSG::Write(int32 timestamp, uint8 A, uint8 V)
{
A &= 0x0F;
if(A == 0x00)
{
select = (V & 0x07);
return;
}
Update(timestamp);
psg_channel *ch = &channel[select];
//if(A == 0x01 || select == 5)
// printf("Write Ch: %d %04x %02x, %d\n", select, A, V, timestamp);
switch(A)
{
default: break;
case 0x01: /* Global sound balance */
globalbalance = V;
vol_pending = true;
break;
case 0x02: /* Channel frequency (LSB) */
if(select > 5) return; // no more than 6 channels, silly game.
ch->frequency = (ch->frequency & 0x0F00) | V;
RecalcFreqCache(select);
RecalcUOFunc(select);
break;
case 0x03: /* Channel frequency (MSB) */
if(select > 5) return; // no more than 6 channels, silly game.
ch->frequency = (ch->frequency & 0x00FF) | ((V & 0x0F) << 8);
RecalcFreqCache(select);
RecalcUOFunc(select);
break;
case 0x04: /* Channel enable, DDA, volume */
if(select > 5) return; // no more than 6 channels, silly game.
if((ch->control & 0x40) && !(V & 0x40))
{
ch->waveform_index = 0;
ch->dda = ch->waveform[ch->waveform_index];
ch->counter = ch->freq_cache;
}
if(!(ch->control & 0x80) && (V & 0x80))
{
if(!(V & 0x40))
{
ch->waveform_index = (ch->waveform_index + 1) & 0x1F;
ch->dda = ch->waveform[ch->waveform_index];
}
}
ch->control = V;
RecalcFreqCache(select);
RecalcUOFunc(select);
vol_pending = true;
break;
case 0x05: /* Channel balance */
if(select > 5) return; // no more than 6 channels, silly game.
ch->balance = V;
vol_pending = true;
break;
case 0x06: /* Channel waveform data */
if(select > 5) return; // no more than 6 channels, silly game.
V &= 0x1F;
if(!(ch->control & 0x40))
{
ch->samp_accum -= ch->waveform[ch->waveform_index];
ch->waveform[ch->waveform_index] = V;
ch->samp_accum += ch->waveform[ch->waveform_index];
}
if((ch->control & 0xC0) == 0x00)
ch->waveform_index = ((ch->waveform_index + 1) & 0x1F);
if(ch->control & 0x80)
{
// According to my tests(on SuperGrafx), writing to this channel
// will update the waveform value cache/latch regardless of DDA mode being enabled.
ch->dda = V;
}
break;
case 0x07: /* Noise enable and frequency */
if(select > 5) return; // no more than 6 channels, silly game.
if(select >= 4)
{
ch->noisectrl = V;
RecalcNoiseFreqCache(select);
RecalcUOFunc(select);
}
break;
case 0x08: /* LFO frequency */
lfofreq = V & 0xFF;
//printf("LFO Freq: %02x\n", V);
break;
case 0x09: /* LFO trigger and control */
//printf("LFO Ctrl: %02x\n", V);
if(V & 0x80)
{
channel[1].waveform_index = 0;
channel[1].dda = channel[1].waveform[channel[1].waveform_index];
channel[1].counter = channel[1].freq_cache;
}
lfoctrl = V;
RecalcFreqCache(0);
RecalcUOFunc(0);
RecalcFreqCache(1);
RecalcUOFunc(1);
break;
}
}
// Don't use INLINE, which has always_inline in it, due to gcc's inability to cope with the type of recursion
// used in this function.
void PCE_PSG::RunChannel(int chc, int32 timestamp, const bool LFO_On)
{
psg_channel *ch = &channel[chc];
int32 running_timestamp = ch->lastts;
int32 run_time = timestamp - ch->lastts;
ch->lastts = timestamp;
if(!run_time)
return;
(this->*ch->UpdateOutput)(running_timestamp, ch);
if(chc >= 4)
{
int32 freq = ch->noise_freq_cache;
ch->noisecount -= run_time;
if(&PCE_PSG::UpdateOutput_Noise == ch->UpdateOutput)
while(ch->noisecount <= 0)
{
CLOCK_LFSR(ch->lfsr);
UpdateOutput_Noise(timestamp + ch->noisecount, ch);
ch->noisecount += freq;
}
else
while(ch->noisecount <= 0)
{
CLOCK_LFSR(ch->lfsr);
ch->noisecount += freq;
}
}
// D7 of control is 0, don't clock the counter at all.
// D7 of lfocontrol is 1(and chc == 1), don't clock the counter at all(not sure about this)
// In DDA mode, don't clock the counter.
// (Noise being enabled isn't handled here since AFAIK it doesn't disable clocking of the waveform portion, its sound just overrides the sound from
// the waveform portion when the noise enable bit is set, which is handled in our RecalcUOFunc).
if(!(ch->control & 0x80) || (chc == 1 && (lfoctrl & 0x80)) || (ch->control & 0x40))
return;
ch->counter -= run_time;
if(!LFO_On && ch->freq_cache <= FREQC7M_COT)
{
if(ch->counter <= 0)
{
const int32 inc_count = ((0 - ch->counter) / ch->freq_cache) + 1;
ch->counter += inc_count * ch->freq_cache;
ch->waveform_index = (ch->waveform_index + inc_count) & 0x1F;
ch->dda = ch->waveform[ch->waveform_index];
}
}
while(ch->counter <= 0)
{
ch->waveform_index = (ch->waveform_index + 1) & 0x1F;
ch->dda = ch->waveform[ch->waveform_index];
(this->*ch->UpdateOutput)(timestamp + ch->counter, ch);
if(LFO_On)
{
RunChannel(1, timestamp + ch->counter, false);
RecalcFreqCache(0);
RecalcUOFunc(0);
ch->counter += (ch->freq_cache <= FREQC7M_COT) ? FREQC7M_COT : ch->freq_cache; // Not particularly accurate, but faster.
}
else
ch->counter += ch->freq_cache;
}
}
void PCE_PSG::UpdateSubLFO(int32 timestamp)
{
for(int chc = 0; chc < 6; chc++)
RunChannel(chc, timestamp, chc == 0);
}
void PCE_PSG::UpdateSubNonLFO(int32 timestamp)
{
for(int chc = 0; chc < 6; chc++)
RunChannel(chc, timestamp, false);
}
void PCE_PSG::Update(int32 timestamp)
{
int32 run_time = timestamp - lastts;
if(vol_pending && !vol_update_counter && !vol_update_which)
{
vol_update_counter = 1;
vol_pending = false;
}
bool lfo_on = (bool)(lfoctrl & 0x03);
if(lfo_on)
{
if(!(channel[1].control & 0x80) || (lfoctrl & 0x80))
{
lfo_on = 0;
RecalcFreqCache(0);
RecalcUOFunc(0);
}
}
int32 clocks = run_time;
int32 running_timestamp = lastts;
while(clocks > 0)
{
int32 chunk_clocks = clocks;
if(vol_update_counter > 0 && chunk_clocks > vol_update_counter)
chunk_clocks = vol_update_counter;
running_timestamp += chunk_clocks;
clocks -= chunk_clocks;
if(lfo_on)
UpdateSubLFO(running_timestamp);
else
UpdateSubNonLFO(running_timestamp);
if(vol_update_counter > 0)
{
vol_update_counter -= chunk_clocks;
if(!vol_update_counter)
{
const int phase = vol_update_which & 1;
const int lr = ((vol_update_which >> 1) & 1) ^ 1;
const int chnum = vol_update_which >> 2;
if(!phase)
{
//printf("Volume update(Read, %d since last): ch=%d, lr=%d, ts=%d\n", running_timestamp - last_read, chnum, lr, running_timestamp);
if(chnum < 6)
{
vol_update_vllatch = GetVL(chnum, lr);
}
//last_read = running_timestamp;
}
else
{
// printf("Volume update(Apply): ch=%d, lr=%d, ts=%d\n", chnum, lr, running_timestamp);
if(chnum < 6)
{
channel[chnum].vl[lr] = vol_update_vllatch;
}
//last_apply = running_timestamp;
}
vol_update_which = (vol_update_which + 1) & 0x1F;
if(vol_update_which)
vol_update_counter = phase ? 1 : 255;
else if(vol_pending)
{
vol_update_counter = phase ? 1 : 255;
vol_pending = false;
}
}
}
lastts = running_timestamp;
}
}
void PCE_PSG::ResetTS(int32 ts_base)
{
lastts = ts_base;
for(int chc = 0; chc < 6; chc++)
channel[chc].lastts = ts_base;
}
void PCE_PSG::Power(const int32 timestamp)
{
// Not sure about power-on values, these are mostly just intuitive guesses(with some laziness thrown in).
if(timestamp != lastts)
Update(timestamp);
// Don't memset channel to 0, there's stuff like lastts and blip_prev_samp that shouldn't be altered on Power().
select = 0;
globalbalance = 0;
lfofreq = 0;
lfoctrl = 0;
for(int ch = 0; ch < 6; ch++)
{
channel[ch].frequency = 0;
channel[ch].control = 0x00;
channel[ch].balance = 0;
memset(channel[ch].waveform, 0, 32);
channel[ch].samp_accum = 0;
channel[ch].waveform_index = 0;
channel[ch].dda = 0x00;
channel[ch].noisectrl = 0x00;
channel[ch].vl[0] = 0x1F;
channel[ch].vl[1] = 0x1F;
channel[ch].samp_accum = 0;
RecalcFreqCache(ch);
RecalcUOFunc(ch);
channel[ch].counter = channel[ch].freq_cache;
if(ch >= 4)
{
RecalcNoiseFreqCache(ch);
}
channel[ch].noisecount = 1;
channel[ch].lfsr = 1;
}
vol_pending = false;
vol_update_counter = 0;
vol_update_which = 0;
}
Reference in New Issue View Git Blame Copy Permalink