Merge pull request #969 from tildearrow/sm8521

Add SM8521 chip support

CMakeLists.txt

@@ -455,6 +455,8 @@ src/engine/platform/sound/snes/SPC_DSP.cpp
 
 src/engine/platform/sound/ga20/iremga20.cpp
 
+src/engine/platform/sound/sm8521.c
+
 src/engine/platform/oplAInterface.cpp
 src/engine/platform/ym2608Interface.cpp
 src/engine/platform/ym2610Interface.cpp
@@ -539,6 +541,7 @@ src/engine/platform/rf5c68.cpp
 src/engine/platform/snes.cpp
 src/engine/platform/k007232.cpp
 src/engine/platform/ga20.cpp
+src/engine/platform/sm8521.cpp
 src/engine/platform/pcmdac.cpp
 src/engine/platform/dummy.cpp
 )

papers/format.md

@@ -284,6 +284,7 @@ size | description
      |   - 0xc5: YM2610B CSM - 20 channels
      |   - 0xc6: K007232 - 2 channels
      |   - 0xc7: GA20 - 4 channels
+     |   - 0xc8: SM8521 - 3 channels
      |   - 0xde: YM2610B extended - 19 channels
      |   - 0xe0: QSound - 19 channels
      |   - 0xfc: Pong - 1 channel

papers/newIns.md

@@ -115,6 +115,7 @@ the following instrument types are available:
 - 45: K007232
 - 46: GA20
 - 47: Pokémon Mini
+- 48: SM8521
 
 the following feature codes are recognized:
 

src/engine/dispatchContainer.cpp

@@ -75,6 +75,7 @@
 #include "platform/vb.h"
 #include "platform/k007232.h"
 #include "platform/ga20.h"
+#include "platform/sm8521.h"
 #include "platform/pcmdac.h"
 #include "platform/dummy.h"
 #include "../ta-log.h"
@@ -489,6 +490,9 @@ void DivDispatchContainer::init(DivSystem sys, DivEngine* eng, int chanCount, do
     case DIV_SYSTEM_GA20:
       dispatch=new DivPlatformGA20;
       break;
+    case DIV_SYSTEM_SM8521:
+      dispatch=new DivPlatformSM8521;
+      break;
     case DIV_SYSTEM_PCM_DAC:
       dispatch=new DivPlatformPCMDAC;
       break;

src/engine/instrument.cpp

@@ -924,6 +924,10 @@ void DivInstrument::putInsData2(SafeWriter* w, bool fui, const DivSong* song) {
         break;
       case DIV_INS_POKEMINI:
         break;
+      case DIV_INS_SM8521:
+        checkForWL=true;
+        if (ws.enabled) featureWS=true;
+        break;
       
       case DIV_INS_MAX:
         break;

src/engine/instrument.h

@@ -78,6 +78,7 @@ enum DivInstrumentType: unsigned short {
   DIV_INS_K007232=45,
   DIV_INS_GA20=46,
   DIV_INS_POKEMINI=47,
+  DIV_INS_SM8521=48,
   DIV_INS_MAX,
   DIV_INS_NULL
 };

src/engine/platform/sm8521.cpp

@@ -0,0 +1,402 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2023 tildearrow and contributors
+ *
+ * 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.
+ */
+
+#include "sm8521.h"
+#include "../engine.h"
+#include <math.h>
+
+//#define rWrite(a,v) pendingWrites[a]=v;
+#define rWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v); if (dumpWrites) {addWrite(a,v);} }
+
+#define CHIP_DIVIDER 64
+
+const char* regCheatSheetSM8521[]={
+  "SGC", "40",
+  "SG0L", "42",
+  "SG1L", "44",
+  "SG0TL", "46",
+  "SG0TH", "47",
+  "SG1TL", "48",
+  "SG1TH", "49",
+  "SG2L", "4A",
+  "SG2TL", "4C",
+  "SG2TH", "4D",
+  "SGDA", "4E",
+  "SG0Wn", "60+n",
+  "SG1Wn", "70+n",
+  NULL
+};
+
+const char** DivPlatformSM8521::getRegisterSheet() {
+  return regCheatSheetSM8521;
+}
+
+void DivPlatformSM8521::acquire(short** buf, size_t len) {
+  while (!writes.empty()) {
+    QueuedWrite w=writes.front();
+    sm8521_write(&sm8521,w.addr,w.val);
+    regPool[w.addr&0xff]=w.val;
+    writes.pop();
+  }
+  for (size_t h=0; h<len; h++) {
+    sm8521_sound_tick(&sm8521,8);
+    buf[0][h]=sm8521.out<<6;
+    for (int i=0; i<2; i++) {
+      oscBuf[i]->data[oscBuf[i]->needle++]=sm8521.sg[i].base.out<<6;
+    }
+    oscBuf[2]->data[oscBuf[2]->needle++]=sm8521.noise.base.out<<6;
+  }
+}
+
+void DivPlatformSM8521::updateWave(int ch) {
+  if (ch<2) {
+    const unsigned char temp=regPool[0x40];
+    rWrite(0x40,temp&~(1<<ch));
+    for (int i=0; i<16; i++) {
+      int nibble1=(chan[ch].ws.output[((i<<1)+chan[ch].antiClickWavePos-1)&31]-8)&0xf;
+      int nibble2=(chan[ch].ws.output[((1+(i<<1))+chan[ch].antiClickWavePos-1)&31]-8)&0xf;
+      rWrite(0x60+i+(ch*16),(nibble2<<4)|nibble1);
+    }
+    if (chan[ch].active) {
+      rWrite(0x40,temp|(1<<ch));
+    }
+    chan[ch].antiClickWavePos&=31;
+  }
+}
+
+void DivPlatformSM8521::tick(bool sysTick) {
+  unsigned char keyState=0x80;
+  for (int i=0; i<3; i++) {
+    // anti-click
+    if (antiClickEnabled && sysTick && chan[i].freq>0) {
+      chan[i].antiClickPeriodCount+=(chipClock/MAX(parent->getCurHz(),1.0f));
+      chan[i].antiClickWavePos+=chan[i].antiClickPeriodCount/chan[i].freq;
+      chan[i].antiClickPeriodCount%=chan[i].freq;
+    }
+
+    chan[i].std.next();
+    if (chan[i].std.vol.had) {
+      chan[i].outVol=((chan[i].vol&31)*MIN(31,chan[i].std.vol.val))>>5;
+      if (!isMuted[i]) {
+        chan[i].volumeChanged=true;
+      }
+    }
+    if (NEW_ARP_STRAT) {
+      chan[i].handleArp();
+    } else if (chan[i].std.arp.had) {
+      if (!chan[i].inPorta) {
+        chan[i].baseFreq=NOTE_PERIODIC(parent->calcArp(chan[i].note,chan[i].std.arp.val));
+      }
+      chan[i].freqChanged=true;
+    }
+    if (chan[i].volumeChanged) {
+      if (isMuted[i]) {
+        rWrite(volMap[i],0);
+      } else {
+        rWrite(volMap[i],chan[i].outVol&0x1f);
+      }
+      chan[i].volumeChanged=false;
+    }
+    if (chan[i].std.wave.had) {
+      if (chan[i].wave!=chan[i].std.wave.val || chan[i].ws.activeChanged()) {
+        chan[i].wave=chan[i].std.wave.val;
+        chan[i].ws.changeWave1(chan[i].wave);
+        if (!chan[i].keyOff) chan[i].keyOn=true;
+      }
+    }
+    if (chan[i].std.pitch.had) {
+      if (chan[i].std.pitch.mode) {
+        chan[i].pitch2+=chan[i].std.pitch.val;
+        CLAMP_VAR(chan[i].pitch2,-32768,32767);
+      } else {
+        chan[i].pitch2=chan[i].std.pitch.val;
+      }
+      chan[i].freqChanged=true;
+    }
+    if (chan[i].std.phaseReset.had && chan[i].std.phaseReset.val==1) {
+      chan[i].antiClickWavePos=0;
+      chan[i].antiClickPeriodCount=0;
+    }
+    if (chan[i].active) {
+      if (chan[i].ws.tick() || (chan[i].std.phaseReset.had && chan[i].std.phaseReset.val==1)) {
+        updateWave(i);
+      }
+    }
+    if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
+      chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,chan[i].fixedArp?chan[i].baseNoteOverride:chan[i].arpOff,chan[i].fixedArp,true,0,chan[i].pitch2,chipClock,CHIP_DIVIDER)-1;
+      if (chan[i].freq<1) chan[i].freq=1;
+      if (chan[i].freq>4095) chan[i].freq=4095;
+      rWrite(freqMap[i][0],chan[i].freq>>8);
+      rWrite(freqMap[i][1],chan[i].freq&0xff);
+      if (chan[i].keyOn) {
+      }
+      if (chan[i].keyOff) {
+      }
+      if (chan[i].keyOn) chan[i].keyOn=false;
+      if (chan[i].keyOff) chan[i].keyOff=false;
+      chan[i].freqChanged=false;
+    }
+    if (!isMuted[i] && chan[i].active) {
+      keyState|=(1<<i);
+    } else {
+      keyState&=~(1<<i);
+    }
+  }
+  if (regPool[0x40]!=keyState) {
+    rWrite(0x40,keyState);
+    regPool[0x40]=keyState;
+  }
+}
+
+int DivPlatformSM8521::dispatch(DivCommand c) {
+  switch (c.cmd) {
+    case DIV_CMD_NOTE_ON: {
+      DivInstrument* ins=parent->getIns(chan[c.chan].ins,DIV_INS_PCE);
+      if (c.value!=DIV_NOTE_NULL) {
+        chan[c.chan].baseFreq=NOTE_PERIODIC(c.value);
+        chan[c.chan].freqChanged=true;
+        chan[c.chan].note=c.value;
+      }
+      chan[c.chan].active=true;
+      chan[c.chan].keyOn=true;
+      chan[c.chan].macroInit(ins);
+      if (!parent->song.brokenOutVol && !chan[c.chan].std.vol.will) {
+        chan[c.chan].outVol=chan[c.chan].vol;
+      }
+      if (chan[c.chan].wave<0) {
+        chan[c.chan].wave=0;
+        chan[c.chan].ws.changeWave1(chan[c.chan].wave);
+      }
+      chan[c.chan].ws.init(ins,32,15,chan[c.chan].insChanged);
+      chan[c.chan].insChanged=false;
+      if (!isMuted[c.chan]) {
+        chan[c.chan].volumeChanged=true;
+      }
+      break;
+    }
+    case DIV_CMD_NOTE_OFF:
+      chan[c.chan].active=false;
+      chan[c.chan].keyOff=true;
+      chan[c.chan].macroInit(NULL);
+      break;
+    case DIV_CMD_NOTE_OFF_ENV:
+    case DIV_CMD_ENV_RELEASE:
+      chan[c.chan].std.release();
+      break;
+    case DIV_CMD_INSTRUMENT:
+      if (chan[c.chan].ins!=c.value || c.value2==1) {
+        chan[c.chan].ins=c.value;
+        chan[c.chan].insChanged=true;
+      }
+      break;
+    case DIV_CMD_VOLUME:
+      if (chan[c.chan].vol!=c.value) {
+        chan[c.chan].vol=c.value;
+        if (!chan[c.chan].std.vol.has) {
+          chan[c.chan].outVol=c.value;
+          if (!isMuted[c.chan]) {
+            chan[c.chan].volumeChanged=true;
+          }
+        }
+      }
+      break;
+    case DIV_CMD_GET_VOLUME:
+      if (chan[c.chan].std.vol.has) {
+        return chan[c.chan].vol;
+      }
+      return chan[c.chan].outVol;
+      break;
+    case DIV_CMD_PITCH:
+      chan[c.chan].pitch=c.value;
+      chan[c.chan].freqChanged=true;
+      break;
+    case DIV_CMD_WAVE:
+      chan[c.chan].wave=c.value;
+      chan[c.chan].ws.changeWave1(chan[c.chan].wave);
+      chan[c.chan].keyOn=true;
+      break;
+    case DIV_CMD_NOTE_PORTA: {
+      int destFreq=NOTE_PERIODIC(c.value2);
+      bool return2=false;
+      if (destFreq>chan[c.chan].baseFreq) {
+        chan[c.chan].baseFreq+=c.value*((parent->song.linearPitch==2)?1:8);
+        if (chan[c.chan].baseFreq>=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      } else {
+        chan[c.chan].baseFreq-=c.value*((parent->song.linearPitch==2)?1:8);
+        if (chan[c.chan].baseFreq<=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      }
+      chan[c.chan].freqChanged=true;
+      if (return2) {
+        chan[c.chan].inPorta=false;
+        return 2;
+      }
+      break;
+    }
+    case DIV_CMD_LEGATO:
+      chan[c.chan].baseFreq=NOTE_PERIODIC(c.value+((HACKY_LEGATO_MESS)?(chan[c.chan].std.arp.val):(0)));
+      chan[c.chan].freqChanged=true;
+      chan[c.chan].note=c.value;
+      break;
+    case DIV_CMD_PRE_PORTA:
+      if (chan[c.chan].active && c.value2) {
+        if (parent->song.resetMacroOnPorta) chan[c.chan].macroInit(parent->getIns(chan[c.chan].ins,DIV_INS_PCE));
+      }
+      if (!chan[c.chan].inPorta && c.value && !parent->song.brokenPortaArp && chan[c.chan].std.arp.will && !NEW_ARP_STRAT) chan[c.chan].baseFreq=NOTE_PERIODIC(chan[c.chan].note);
+      chan[c.chan].inPorta=c.value;
+      break;
+    case DIV_CMD_GET_VOLMAX:
+      return 31;
+      break;
+    case DIV_CMD_MACRO_OFF:
+      chan[c.chan].std.mask(c.value,true);
+      break;
+    case DIV_CMD_MACRO_ON:
+      chan[c.chan].std.mask(c.value,false);
+      break;
+    case DIV_ALWAYS_SET_VOLUME:
+      return 1;
+      break;
+    default:
+      break;
+  }
+  return 1;
+}
+
+void DivPlatformSM8521::muteChannel(int ch, bool mute) {
+  isMuted[ch]=mute;
+  chan[ch].volumeChanged=true;
+  if (mute) {
+    rWrite(0x40,regPool[0x40]&~(1<<ch));
+  } else if (chan[ch].active) {
+    rWrite(0x40,regPool[0x40]|0x80|(1<<ch));
+  }
+}
+
+void DivPlatformSM8521::forceIns() {
+  for (int i=0; i<3; i++) {
+    chan[i].insChanged=true;
+    chan[i].freqChanged=true;
+    updateWave(i);
+  }
+}
+
+void* DivPlatformSM8521::getChanState(int ch) {
+  return &chan[ch];
+}
+
+DivMacroInt* DivPlatformSM8521::getChanMacroInt(int ch) {
+  return &chan[ch].std;
+}
+
+DivDispatchOscBuffer* DivPlatformSM8521::getOscBuffer(int ch) {
+  return oscBuf[ch];
+}
+
+unsigned char* DivPlatformSM8521::getRegisterPool() {
+  return regPool;
+}
+
+int DivPlatformSM8521::getRegisterPoolSize() {
+  return 256;
+}
+
+void DivPlatformSM8521::reset() {
+  while (!writes.empty()) writes.pop();
+  memset(regPool,0,256);
+  for (int i=0; i<3; i++) {
+    chan[i]=DivPlatformSM8521::Channel();
+    chan[i].std.setEngine(parent);
+    chan[i].ws.setEngine(parent);
+    chan[i].ws.init(NULL,32,15,false);
+  }
+  if (dumpWrites) {
+    addWrite(0xffffffff,0);
+  }
+  sm8521_reset(&sm8521);
+  rWrite(0x40,0x80); // initialize SGC
+}
+
+int DivPlatformSM8521::getOutputCount() {
+  return 1;
+}
+
+bool DivPlatformSM8521::keyOffAffectsArp(int ch) {
+  return true;
+}
+
+void DivPlatformSM8521::notifyWaveChange(int wave) {
+  for (int i=0; i<2; i++) {
+    if (chan[i].wave==wave) {
+      chan[i].ws.changeWave1(wave);
+      updateWave(i);
+    }
+  }
+}
+
+void DivPlatformSM8521::notifyInsDeletion(void* ins) {
+  for (int i=0; i<3; i++) {
+    chan[i].std.notifyInsDeletion((DivInstrument*)ins);
+  }
+}
+
+void DivPlatformSM8521::setFlags(const DivConfig& flags) {
+  antiClickEnabled=!flags.getBool("noAntiClick",false);
+  chipClock=11059200;
+  CHECK_CUSTOM_CLOCK;
+  rate=chipClock/4/8; // CKIN -> fCLK(/2) -> Function blocks (/2)
+  for (int i=0; i<3; i++) {
+    oscBuf[i]->rate=rate;
+  }
+}
+
+void DivPlatformSM8521::poke(unsigned int addr, unsigned short val) {
+  rWrite(addr,val);
+}
+
+void DivPlatformSM8521::poke(std::vector<DivRegWrite>& wlist) {
+  for (DivRegWrite& i: wlist) rWrite(i.addr,i.val);
+}
+
+int DivPlatformSM8521::init(DivEngine* p, int channels, int sugRate, const DivConfig& flags) {
+  parent=p;
+  dumpWrites=false;
+  skipRegisterWrites=false;
+  for (int i=0; i<3; i++) {
+    isMuted[i]=false;
+    oscBuf[i]=new DivDispatchOscBuffer;
+  }
+  setFlags(flags);
+  reset();
+  return 6;
+}
+
+void DivPlatformSM8521::quit() {
+  for (int i=0; i<3; i++) {
+    delete oscBuf[i];
+  }
+}
+
+DivPlatformSM8521::~DivPlatformSM8521() {
+}

src/engine/platform/sm8521.h

@@ -0,0 +1,86 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2023 tildearrow and contributors
+ *
+ * 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.
+ */
+
+#ifndef _SM8521_H
+#define _SM8521_H
+
+#include "../dispatch.h"
+#include <queue>
+#include "../waveSynth.h"
+#include "sound/sm8521.h"
+
+class DivPlatformSM8521: public DivDispatch {
+  const unsigned char volMap[3]={0x42,0x44,0x4a};
+
+  const unsigned char freqMap[3][2]={{0x46,0x47},{0x48,0x49},{0x4c,0x4d}};
+
+  struct Channel: public SharedChannel<signed char> {
+    int antiClickPeriodCount, antiClickWavePos;
+    signed short wave;
+    bool volumeChanged;
+    DivWaveSynth ws;
+    Channel():
+      SharedChannel<signed char>(31),
+      antiClickPeriodCount(0),
+      antiClickWavePos(0),
+      wave(-1),
+      volumeChanged(false) {}
+  };
+  Channel chan[3];
+  DivDispatchOscBuffer* oscBuf[3];
+  bool isMuted[3];
+  struct QueuedWrite {
+      unsigned short addr;
+      unsigned char val;
+      QueuedWrite(unsigned short a, unsigned char v): addr(a), val(v) {}
+  };
+  std::queue<QueuedWrite> writes;
+
+  bool antiClickEnabled;
+  struct sm8521_t sm8521;
+  unsigned char regPool[256];
+  void updateWave(int ch);
+  friend void putDispatchChip(void*,int);
+  friend void putDispatchChan(void*,int,int);
+  public:
+    void acquire(short** buf, size_t len);
+    int dispatch(DivCommand c);
+    void* getChanState(int chan);
+    DivMacroInt* getChanMacroInt(int ch);
+    DivDispatchOscBuffer* getOscBuffer(int chan);
+    unsigned char* getRegisterPool();
+    int getRegisterPoolSize();
+    void reset();
+    void forceIns();
+    void tick(bool sysTick=true);
+    void muteChannel(int ch, bool mute);
+    int getOutputCount();
+    bool keyOffAffectsArp(int ch);
+    void setFlags(const DivConfig& flags);
+    void notifyWaveChange(int wave);
+    void notifyInsDeletion(void* ins);
+    void poke(unsigned int addr, unsigned short val);
+    void poke(std::vector<DivRegWrite>& wlist);
+    const char** getRegisterSheet();
+    int init(DivEngine* parent, int channels, int sugRate, const DivConfig& flags);
+    void quit();
+    ~DivPlatformSM8521();
+};
+
+#endif

src/engine/platform/sound/sm8521.c

@@ -0,0 +1,235 @@
+/*
+
+============================================================================
+
+SM8521 sound emulator
+by cam900
+
+This file is licensed under zlib license.
+
+============================================================================
+
+zlib License
+
+(C) 2023-present cam900 and contributors
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+
+============================================================================
+
+TODO:
+- needs hardware test
+
+*/
+
+#include "sm8521.h"
+#include <stdlib.h>
+
+enum sm8521_sgc
+{
+	SM8521_SGC_SONDOUT = (1 << 7),
+	SM8521_SGC_DIROUT = (1 << 3),
+	SM8521_SGC_SG2OUT = (1 << 2),
+	SM8521_SGC_SG1OUT = (1 << 1),
+	SM8521_SGC_SG0OUT = (1 << 0)
+};
+
+void sm8521_sg_wave_tick(struct sm8521_wave_t *sg, const int cycle)
+{
+	sg->base.counter += cycle;
+	while (sg->base.counter >= (sg->base.t + 1))
+	{
+		sg->addr++;
+		sg->base.counter -= (sg->base.t + 1);
+	}
+	int wave = (sg->wave[(sg->addr >> 1) & 0xf] >> ((sg->addr & 1) << 2)) & 0xf;
+	if (wave & 0x8)
+	{
+		wave = -(0x8 - (wave & 0x7));
+	}
+	sg->base.out = (wave * sg->base.level) >> 1; // scale out to 8bit
+}
+
+void sm8521_noise_tick(struct sm8521_noise_t *noise, const int cycle)
+{
+	noise->base.counter += cycle;
+	while (noise->base.counter >= (noise->base.t + 1))
+	{
+		noise->lfsr = rand() & 0x1; // unknown algorithm
+		noise->base.counter -= (noise->base.t + 1);
+	}
+	noise->base.out = (((noise->lfsr & 0x1) ? 7 : -8) * noise->base.level) >> 1; // scale out to 8bit
+}
+
+void sm8521_sound_tick(struct sm8521_t *sm8521, const int cycle)
+{
+	int out = 0;
+	if (sm8521->sgc & SM8521_SGC_SONDOUT)
+	{
+		if (sm8521->sgc & SM8521_SGC_DIROUT)
+		{
+			out = sm8521->sgda - 0x80;
+		}
+		else
+		{
+			if (sm8521->sgc & SM8521_SGC_SG0OUT)
+			{
+				sm8521_sg_wave_tick(&sm8521->sg[0], cycle);
+				out += sm8521->sg[0].base.out;
+			}
+			if (sm8521->sgc & SM8521_SGC_SG1OUT)
+			{
+				sm8521_sg_wave_tick(&sm8521->sg[1], cycle);
+				out += sm8521->sg[1].base.out;
+			}
+			if (sm8521->sgc & SM8521_SGC_SG2OUT)
+			{
+				sm8521_noise_tick(&sm8521->noise, cycle);
+				out += sm8521->noise.base.out;
+			}
+			out = (out < -0x80) ? -0x80 : ((out > 0x7f) ? 0x7f : out); // clamp
+		}
+	}
+	sm8521->out = out;
+}
+
+void sm8521_reset(struct sm8521_t *sm8521)
+{
+	for (int i = 0; i < 2; i++)
+	{
+		sm8521->sg[i].base.t = 0;
+		sm8521->sg[i].base.level = 0;
+		sm8521->sg[i].base.out = 0;
+		sm8521->sg[i].base.counter = 0;
+		sm8521->sg[i].addr = 0;
+		for (int j = 0; j < 16; j++)
+		{
+			sm8521->sg[i].wave[j] = 0;
+		}
+	}
+	sm8521->noise.base.t = 0;
+	sm8521->noise.base.level = 0;
+	sm8521->noise.base.out = 0;
+	sm8521->noise.base.counter = 0;
+	sm8521->noise.lfsr = 0;
+	sm8521->out = 0;
+	sm8521->sgda = 0;
+	sm8521->sgc = 0;
+}
+
+unsigned char sm8521_read(struct sm8521_t *sm8521, const unsigned char a)
+{
+	if ((a & 0xe0) == 0x60)
+	{
+		if ((a & 0x10) && (!(sm8521->sgc & SM8521_SGC_SG1OUT))) // 0x70-0x7f SG1W0-15
+		{
+			return sm8521->sg[1].wave[a & 0xf];
+		}
+		else if ((!(a & 0x10)) && (!(sm8521->sgc & SM8521_SGC_SG0OUT))) // 0x60-0x6f SG0W0-15
+		{
+			return sm8521->sg[0].wave[a & 0xf];
+		}
+		return 0;
+	}
+	switch (a)
+	{
+		case 0x40: // SGC
+			return sm8521->sgc;
+			break;
+		case 0x42: // SG0L
+			return sm8521->sg[0].base.level & 0x1f;
+			break;
+		case 0x44: // SG1L
+			return sm8521->sg[1].base.level & 0x1f;
+			break;
+		case 0x46: // SG0TH
+			return (sm8521->sg[0].base.t >> 8) & 0xf;
+			break;
+		case 0x47: // SG0TL
+			return sm8521->sg[0].base.t & 0xff;
+			break;
+		case 0x48: // SG1TH
+			return (sm8521->sg[1].base.t >> 8) & 0xf;
+			break;
+		case 0x49: // SG1TL
+			return sm8521->sg[1].base.t & 0x0ff;
+			break;
+		case 0x4a: // SG2L
+			return sm8521->noise.base.level & 0x1f;
+			break;
+		case 0x4c: // SG2TH
+			return (sm8521->noise.base.t >> 8) & 0xf;
+			break;
+		case 0x4d: // SG2TL
+			return sm8521->noise.base.t & 0xff;
+			break;
+		default:
+			return 0;
+			break;
+	}
+}
+void sm8521_write(struct sm8521_t *sm8521, const unsigned char a, const unsigned char d)
+{
+	if ((a & 0xe0) == 0x60)
+	{
+		if ((a & 0x10) && (!(sm8521->sgc & SM8521_SGC_SG1OUT))) // 0x70-0x7f SG1W0-15
+		{
+			sm8521->sg[1].wave[a & 0xf] = d;
+		}
+		else if ((!(a & 0x10)) && (!(sm8521->sgc & SM8521_SGC_SG0OUT))) // 0x60-0x6f SG0W0-15
+		{
+			sm8521->sg[0].wave[a & 0xf] = d;
+		}
+		return;
+	}
+	switch (a)
+	{
+		case 0x40: // SGC
+			sm8521->sgc = d;
+			break;
+		case 0x42: // SG0L
+			sm8521->sg[0].base.level = d & 0x1f;
+			break;
+		case 0x44: // SG1L
+			sm8521->sg[1].base.level = d & 0x1f;
+			break;
+		case 0x46: // SG0TH
+			sm8521->sg[0].base.t = (sm8521->sg[0].base.t & 0x0ff) | ((d << 8) & 0xf00);
+			break;
+		case 0x47: // SG0TL
+			sm8521->sg[0].base.t = (sm8521->sg[0].base.t & 0xf00) | (d & 0x0ff);
+			break;
+		case 0x48: // SG1TH
+			sm8521->sg[1].base.t = (sm8521->sg[1].base.t & 0x0ff) | ((d << 8) & 0xf00);
+			break;
+		case 0x49: // SG1TL
+			sm8521->sg[1].base.t = (sm8521->sg[1].base.t & 0xf00) | (d & 0x0ff);
+			break;
+		case 0x4a: // SG2L
+			sm8521->noise.base.level = d & 0x1f;
+			break;
+		case 0x4c: // SG2TH
+			sm8521->noise.base.t = (sm8521->noise.base.t & 0x0ff) | ((d << 8) & 0xf00);
+			break;
+		case 0x4d: // SG2TL
+			sm8521->noise.base.t = (sm8521->noise.base.t & 0xf00) | (d & 0x0ff);
+			break;
+		case 0x4e: // SGDA
+			sm8521->sgda = d;
+			break;
+	}
+}

src/engine/platform/sound/sm8521.h

@@ -0,0 +1,92 @@
+/*
+
+============================================================================
+
+SM8521 sound emulator
+by cam900
+
+This file is licensed under zlib license.
+
+============================================================================
+
+zlib License
+
+(C) 2023-present cam900 and contributors
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+
+============================================================================
+
+TODO:
+- needs hardware test
+
+*/
+
+#ifndef _SM8521_EMU_H
+#define _SM8521_EMU_H
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+struct sm8521_sg_t
+{
+	unsigned short t; // Time constant register
+	unsigned char level; // Output level control register
+	signed short out; // output
+	int counter; // clock counter
+};
+
+struct sm8521_wave_t
+{
+	struct sm8521_sg_t base;
+	unsigned char addr; // waveform address
+	unsigned char wave[16]; // 4 bit waveform (32 nybbles)
+};
+
+struct sm8521_noise_t
+{
+	struct sm8521_sg_t base;
+	unsigned int lfsr; // LFSR
+};
+
+struct sm8521_t
+{
+	struct sm8521_wave_t sg[2];
+	struct sm8521_noise_t noise;
+	signed short out; // output
+	signed char sgda; // D/A direct output register (write only)
+	unsigned char sgc; // Control register
+};
+
+void sm8521_sg_wave_tick(struct sm8521_wave_t *sg, const int cycle);
+
+void sm8521_noise_tick(struct sm8521_noise_t *noise, const int cycle);
+
+void sm8521_sound_tick(struct sm8521_t *sm8521, const int cycle);
+
+void sm8521_reset(struct sm8521_t *sm8521);
+
+unsigned char sm8521_read(struct sm8521_t *sm8521, const unsigned char a);
+void sm8521_write(struct sm8521_t *sm8521, const unsigned char a, const unsigned char d);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // _SM8521_EMU_H

src/engine/song.h

@@ -124,7 +124,8 @@ enum DivSystem {
   DIV_SYSTEM_YM2610_CSM,
   DIV_SYSTEM_YM2610B_CSM,
   DIV_SYSTEM_YM2203_CSM,
-  DIV_SYSTEM_YM2608_CSM
+  DIV_SYSTEM_YM2608_CSM,
+  DIV_SYSTEM_SM8521
 };
 
 struct DivGroovePattern {

src/engine/sysDef.cpp

@@ -1822,6 +1822,17 @@ void DivEngine::registerSystems() {
     {DIV_INS_AMIGA, DIV_INS_AMIGA, DIV_INS_AMIGA, DIV_INS_AMIGA}
   );
 
+  sysDefs[DIV_SYSTEM_SM8521]=new DivSysDef(
+    "Sharp SM8521", NULL, 0xc8, 0, 3, false, true, 0, false, 0,
+    "a SoC with wavetable sound hardware.",
+    {"Channel 1", "Channel 2", "Noise"},
+    {"CH1", "CH2", "NS"},
+    {DIV_CH_WAVE, DIV_CH_WAVE, DIV_CH_NOISE},
+    {DIV_INS_SM8521, DIV_INS_SM8521, DIV_INS_SM8521},
+    {},
+    namcoEffectHandlerMap
+  );
+
   sysDefs[DIV_SYSTEM_DUMMY]=new DivSysDef(
     "Dummy System", NULL, 0xfd, 0, 8, false, true, 0, false, 0,
     "this is a system designed for testing purposes.",

src/gui/dataList.cpp

@@ -430,6 +430,10 @@ void FurnaceGUI::drawInsList(bool asChild) {
               ImGui::PushStyleColor(ImGuiCol_Text,uiColors[GUI_COLOR_INSTR_POKEMINI]);
               name=fmt::sprintf(ICON_FA_BAR_CHART "##_INS%d",i);
               break;
+            case DIV_INS_SM8521:
+              ImGui::PushStyleColor(ImGuiCol_Text,uiColors[GUI_COLOR_INSTR_SM8521]);
+              name=fmt::sprintf(ICON_FA_PIE_CHART "##_INS%d",i);
+              break;
             default:
               ImGui::PushStyleColor(ImGuiCol_Text,uiColors[GUI_COLOR_INSTR_UNKNOWN]);
               name=fmt::sprintf(ICON_FA_QUESTION "##_INS%d",i);

src/gui/gui.h

@@ -189,6 +189,7 @@ enum FurnaceGUIColors {
   GUI_COLOR_INSTR_K007232,
   GUI_COLOR_INSTR_GA20,
   GUI_COLOR_INSTR_POKEMINI,
+  GUI_COLOR_INSTR_SM8521,
   GUI_COLOR_INSTR_UNKNOWN,
 
   GUI_COLOR_CHANNEL_BG,

src/gui/guiConst.cpp

@@ -129,6 +129,7 @@ const char* insTypes[DIV_INS_MAX+1]={
   "K007232",
   "GA20",
   "Pokémon Mini",
+  "SM8521",
   NULL
 };
 
@@ -818,6 +819,7 @@ const FurnaceGUIColorDef guiColors[GUI_COLOR_MAX]={
   D(GUI_COLOR_INSTR_K007232,"",ImVec4(1.0f,0.8f,0.1f,1.0f)),
   D(GUI_COLOR_INSTR_GA20,"",ImVec4(0.1f,1.0f,0.4f,1.0f)),
   D(GUI_COLOR_INSTR_POKEMINI,"",ImVec4(1.0f,1.0f,0.3f,1.0f)),
+  D(GUI_COLOR_INSTR_SM8521,"",ImVec4(1.0f,1.0f,0.0f,1.0f)),
   D(GUI_COLOR_INSTR_UNKNOWN,"",ImVec4(0.3f,0.3f,0.3f,1.0f)),
 
   D(GUI_COLOR_CHANNEL_BG,"",ImVec4(0.4f,0.6f,0.8f,1.0f)),
@@ -998,6 +1000,7 @@ const int availableSystems[]={
   DIV_SYSTEM_MSM5232,
   DIV_SYSTEM_K007232,
   DIV_SYSTEM_GA20,
+  DIV_SYSTEM_SM8521,
   DIV_SYSTEM_PCM_DAC,
   DIV_SYSTEM_PONG,
   0 // don't remove this last one!
@@ -1084,6 +1087,7 @@ const int chipsSpecial[]={
   DIV_SYSTEM_PET,
   DIV_SYSTEM_VRC6,
   DIV_SYSTEM_MMC5,
+  DIV_SYSTEM_SM8521,
   0 // don't remove this last one!
 };
 

src/gui/insEdit.cpp

@@ -4762,11 +4762,13 @@ void FurnaceGUI::drawInsEdit() {
             (ins->type==DIV_INS_VBOY) ||
             ins->type==DIV_INS_SCC ||
             ins->type==DIV_INS_SNES ||
-            ins->type==DIV_INS_NAMCO) {
+            ins->type==DIV_INS_NAMCO ||
+            ins->type==DIV_INS_SM8521) {
           if (ImGui::BeginTabItem("Wavetable")) {
             switch (ins->type) {
               case DIV_INS_GB:
               case DIV_INS_NAMCO:
+              case DIV_INS_SM8521:
               case DIV_INS_SWAN:
                 wavePreviewLen=32;
                 wavePreviewHeight=15;
@@ -4968,7 +4970,7 @@ void FurnaceGUI::drawInsEdit() {
               }
             }
           }
-          if (ins->type==DIV_INS_PCE || ins->type==DIV_INS_AY8930) {
+          if (ins->type==DIV_INS_PCE || ins->type==DIV_INS_AY8930 || ins->type==DIV_INS_SM8521) {
             volMax=31;
           }
           if (ins->type==DIV_INS_OPL || ins->type==DIV_INS_OPL_DRUMS || ins->type==DIV_INS_VERA || ins->type==DIV_INS_VRC6_SAW) {
@@ -5067,7 +5069,8 @@ void FurnaceGUI::drawInsEdit() {
           }
           if (ins->type==DIV_INS_TIA || ins->type==DIV_INS_AMIGA || ins->type==DIV_INS_SCC ||
               ins->type==DIV_INS_PET || ins->type==DIV_INS_VIC || ins->type==DIV_INS_SEGAPCM ||
-              ins->type==DIV_INS_FM || ins->type==DIV_INS_K007232 || ins->type==DIV_INS_GA20) {
+              ins->type==DIV_INS_FM || ins->type==DIV_INS_K007232 || ins->type==DIV_INS_GA20 ||
+              ins->type==DIV_INS_SM8521) {
             dutyMax=0;
           }
           if (ins->type==DIV_INS_VBOY) {

src/gui/presets.cpp

@@ -2571,6 +2571,11 @@ void FurnaceGUI::initSystemPresets() {
       CH(DIV_SYSTEM_SFX_BEEPER, 1.0f, 0, "")
     }
   );
+  ENTRY(
+    "Sharp SM8521", {
+      CH(DIV_SYSTEM_SM8521, 1.0f, 0, "")
+    }
+  );
   if (settings.hiddenSystems) {
     ENTRY(
       "Dummy System", {

src/gui/settings.cpp

@@ -1907,6 +1907,7 @@ void FurnaceGUI::drawSettings() {
               UI_COLOR_CONFIG(GUI_COLOR_INSTR_K007232,"K007232");
               UI_COLOR_CONFIG(GUI_COLOR_INSTR_GA20,"GA20");
               UI_COLOR_CONFIG(GUI_COLOR_INSTR_POKEMINI,"Pokémon Mini");
+              UI_COLOR_CONFIG(GUI_COLOR_INSTR_SM8521,"SM8521");
               UI_COLOR_CONFIG(GUI_COLOR_INSTR_UNKNOWN,"Other/Unknown");
               ImGui::TreePop();
             }

src/gui/sysConf.cpp

@@ -1694,6 +1694,20 @@ bool FurnaceGUI::drawSysConf(int chan, DivSystem type, DivConfig& flags, bool mo
       }
       break;
     }
+    case DIV_SYSTEM_SM8521:  {
+      bool noAntiClick=flags.getBool("noAntiClick",false);
+
+      if (ImGui::Checkbox("Disable anti-click",&noAntiClick)) {
+        altered=true;
+      }
+
+      if (altered) {
+        e->lockSave([&]() {
+          flags.set("noAntiClick",noAntiClick);
+        });
+      }
+      break;
+    }
     case DIV_SYSTEM_SWAN:
     case DIV_SYSTEM_BUBSYS_WSG:
     case DIV_SYSTEM_PET: