SMS: add modified Nuked-PSG core

CMakeLists.txt

@@ -275,6 +275,7 @@ extern/adpcm/ymb_codec.c
 extern/adpcm/ymz_codec.c
 
 extern/Nuked-OPN2/ym3438.c
+extern/Nuked-PSG/ympsg.c
 extern/opm/opm.c
 extern/Nuked-OPLL/opll.c
 extern/opl/opl3.c

extern/Nuked-PSG/LICENSE

@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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extern/Nuked-PSG/README.md

@@ -0,0 +1,6 @@
+# Nuked-PSG
+Yamaha YM7101 PSG emulator
+
+# modification disclaimer
+
+this is a modified version of Nuked-PSG which adds support for changing the noise LFSR size and taps.

extern/Nuked-PSG/ympsg.c

@@ -0,0 +1,403 @@
+// Copyright (C) 2021 Nuke.YKT
+// License: GPLv2+
+// Version 1.0.1
+#include <string.h>
+#include "ympsg.h"
+
+const float ympsg_vol[17] = {
+    1.0, 0.772, 0.622, 0.485, 0.382, 0.29, 0.229, 0.174, 0.132, 0.096, 0.072, 0.051, 0.034, 0.019, 0.009, 0.0, -1.059
+};
+
+static void YMPSG_WriteLatch(ympsg_t *chip)
+{
+    uint8_t data = chip->data;
+    if (chip->data_mask)
+    {
+        data = 0;
+    }
+    if (data & 128)
+    {
+        chip->latch = (data >> 4) & 7;
+    }
+}
+
+static void YMPSG_UpdateRegisters(ympsg_t* chip)
+{
+    uint8_t data = chip->data;
+    if (chip->data_mask)
+    {
+        data = 0;
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 1))
+    {
+        chip->volume[0] = data & 15;
+        if (chip->data_mask)
+        {
+            chip->volume[0] = 15;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 3))
+    {
+        chip->volume[1] = data & 15;
+        if (chip->data_mask)
+        {
+            chip->volume[1] = 15;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 4))
+    {
+        if ((data & 128) || chip->reg_reset)
+        {
+            chip->freq[2] &= 1008;
+            chip->freq[2] |= data & 15;
+        }
+        if (!(data & 128))
+        {
+            chip->freq[2] &= 15;
+            chip->freq[2] |= (data << 4) & 1008;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 2))
+    {
+        if ((data & 128) || chip->reg_reset)
+        {
+            chip->freq[1] &= 1008;
+            chip->freq[1] |= data & 15;
+        }
+        if (!(data & 128))
+        {
+            chip->freq[1] &= 15;
+            chip->freq[1] |= (data << 4) & 1008;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 5))
+    {
+        chip->volume[2] = data & 15;
+        if (chip->data_mask)
+        {
+            chip->volume[2] = 15;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 0))
+    {
+        if ((data & 128) || chip->reg_reset)
+        {
+            chip->freq[0] &= 1008;
+            chip->freq[0] |= data & 15;
+        }
+        if (!(data & 128))
+        {
+            chip->freq[0] &= 15;
+            chip->freq[0] |= (data << 4) & 1008;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 7))
+    {
+        chip->volume[3] = data & 15;
+        if (chip->data_mask)
+        {
+            chip->volume[3] = 15;
+        }
+    }
+    if (chip->reg_reset || (chip->write_flag_l && chip->latch == 6))
+    {
+        chip->noise_data = data & 7;
+        chip->noise_trig = 1;
+    }
+}
+
+static void YMPSG_ClockInternal1(ympsg_t *chip)
+{
+    uint16_t freq = 0;
+    uint8_t chan_sel = chip->chan_sel;
+    uint8_t noise_of, noise_bit1, noise_bit2, noise_next;
+    if ((chip->noise_data & 3) == 3)
+    {
+        noise_of = (chip->sign >> 1) & 1;
+    }
+    else
+    {
+        noise_of = chip->sign & 1;
+    }
+    if (chip->noise_trig_l || (chip->ic_latch2 & 1))
+    {
+        chip->noise = 0;
+    }
+    else if (noise_of && !chip->noise_of)
+    {
+        noise_bit1 = (chip->noise >> 15) & 1;
+        noise_bit2 = (chip->noise >> 12) & 1;
+        noise_bit1 ^= noise_bit2;
+        noise_next = ((noise_bit1 && ((chip->noise_data >> 2) & 1)) || ((chip->noise & 32767) == 0));
+        chip->noise <<= 1;
+        chip->noise |= noise_next;
+    }
+    chip->noise_of = noise_of;
+    if (chip->ic_latch2 & 2)
+    {
+        chan_sel = 0;
+    }
+    if (chip->chan_sel & 1)
+    {
+        freq |= chip->freq[0];
+    }
+    if (chip->chan_sel & 2)
+    {
+        freq |= chip->freq[1];
+    }
+    if (chip->chan_sel & 4)
+    {
+        freq |= chip->freq[2];
+    }
+    if (chip->chan_sel & 8)
+    {
+        if ((chip->noise_data & 3) == 0)
+        {
+            freq |= 16;
+        }
+        if ((chip->noise_data & 3) == 1)
+        {
+            freq |= 32;
+        }
+        if ((chip->noise_data & 3) == 2)
+        {
+            freq |= 64;
+        }
+    }
+    if (chip->chan_sel & 1)
+    {
+        chip->sign ^= chip->counter_of & 15;
+    }
+    if (chip->ic_latch2 & 2)
+    {
+        chip->sign = 0;
+    }
+    chip->counter_of <<= 1;
+    if (chip->counter[chip->rot] >= freq)
+    {
+        chip->counter_of |= 1;
+        chip->counter[chip->rot] = 0;
+    }
+    if (chip->ic_latch2 & 2)
+    {
+        chip->counter[chip->rot] = 0;
+    }
+    chip->counter[chip->rot]++;
+    chip->counter[chip->rot] &= 1023;
+    if ((chip->ic_latch2 & 1) || (chip->chan_sel & 7) != 0)
+    {
+        chip->chan_sel <<= 1;
+    }
+    else
+    {
+        chip->chan_sel <<= 1;
+        chip->chan_sel |= 1;
+    }
+    chip->ic_latch2 <<= 1;
+    chip->ic_latch2 |= chip->ic & 1;
+    chip->noise_trig_l = chip->noise_trig;
+}
+
+static void YMPSG_ClockInternal2(ympsg_t *chip)
+{
+    chip->data_mask = (chip->ic_latch2 >> 1) & 1;
+    chip->reg_reset = (chip->ic_latch2 >> 0) & 1;
+    if (chip->noise_trig_l)
+    {
+        chip->noise_trig = 0;
+    }
+    YMPSG_UpdateRegisters(chip);
+
+    chip->rot = (chip->rot + 1) & 3;
+    chip->sign_l = chip->sign;
+    chip->noise_sign_l = (chip->noise >> 14) & 1;
+}
+
+static void YMPSG_UpdateSample(ympsg_t *chip)
+{
+    uint32_t i;
+    uint8_t sign = chip->sign & 14;
+    sign |= chip->noise_sign_l;
+    if (chip->test & 1)
+    {
+        sign |= 15;
+    }
+    for (i = 0; i < 4; i++)
+    {
+        if ((sign >> (3 - i)) & 1)
+        {
+            chip->volume_out[i] = chip->volume[i];
+        }
+        else
+        {
+            chip->volume_out[i] = 15;
+        }
+    }
+}
+
+void YMPSG_Write(ympsg_t *chip, uint8_t data)
+{
+    chip->data = data;
+    chip->write_flag = 1;
+}
+
+uint16_t YMPSG_Read(ympsg_t *chip)
+{
+    uint16_t data = 0;
+    uint32_t i;
+    YMPSG_UpdateSample(chip);
+    for (i = 0; i < 4; i++)
+    {
+        data |= chip->volume_out[i] << ((3 - i) * 4);
+    }
+    return data;
+}
+
+void YMPSG_Init(ympsg_t *chip)
+{
+    uint32_t i;
+    memset(chip, 0, sizeof(ympsg_t));
+    YMPSG_SetIC(chip, 1);
+    for (i = 0; i < 16; i++)
+    {
+        YMPSG_Clock(chip);
+    }
+    YMPSG_SetIC(chip, 0);
+}
+
+void YMPSG_SetIC(ympsg_t *chip, uint32_t ic)
+{
+    chip->ic = (uint8_t)ic;
+}
+
+void YMPSG_Clock(ympsg_t *chip)
+{
+    uint8_t prescaler2_latch;
+    prescaler2_latch = chip->prescaler_2;
+    chip->prescaler_2 += chip->prescaler_1;
+    chip->prescaler_2 &= 1;
+    chip->prescaler_1 ^= 1;
+    if ((chip->ic_latch1 & 3) == 2)
+    {
+        chip->prescaler_1 = 0;
+        chip->prescaler_2 = 0;
+    }
+    chip->ic_latch1 <<= 1;
+    chip->ic_latch1 |= chip->ic & 1;
+    YMPSG_UpdateRegisters(chip);
+    chip->write_flag_l = 0;
+    if (chip->write_flag)
+    {
+        YMPSG_WriteLatch(chip);
+        chip->write_flag = 0;
+        chip->write_flag_l = 1;
+    }
+    if (chip->prescaler_1)
+    {
+        if (!prescaler2_latch)
+        {
+            YMPSG_ClockInternal1(chip);
+        }
+        else
+        {
+            YMPSG_ClockInternal2(chip);
+        }
+    }
+}
+
+float YMPSG_GetOutput(ympsg_t *chip)
+{
+    float sample = 0.f;
+    uint32_t i;
+    YMPSG_UpdateSample(chip);
+    if (chip->test & 1)
+    {
+        sample += ympsg_vol[chip->volume_out[chip->test >> 1]];
+        sample += ympsg_vol[16] * 3.f;
+    }
+    else if (!chip->mute)
+    {
+        sample += ympsg_vol[chip->volume_out[0]];
+        sample += ympsg_vol[chip->volume_out[1]];
+        sample += ympsg_vol[chip->volume_out[2]];
+        sample += ympsg_vol[chip->volume_out[3]];
+    }
+    else
+    {
+        for (i = 0; i < 4; i++)
+        {
+            if (!((chip->mute>>i) & 1))
+                sample += ympsg_vol[chip->volume_out[i]];
+        }
+    }
+    return sample;
+}
+
+void YMPSG_Test(ympsg_t *chip, uint16_t test)
+{
+    chip->test = (test >> 9) & 7;
+}
+
+
+void YMPSG_Generate(ympsg_t *chip, int32_t *buf)
+{
+    uint32_t i;
+    float out;
+
+    for (i = 0; i < 16; i++)
+    {
+        YMPSG_Clock(chip);
+
+        while (chip->writebuf[chip->writebuf_cur].time <= chip->writebuf_samplecnt)
+        {
+            if (!chip->writebuf[chip->writebuf_cur].stat)
+            {
+                break;
+            }
+            chip->writebuf[chip->writebuf_cur].stat = 0;
+            YMPSG_Write(chip, chip->writebuf[chip->writebuf_cur].data);
+            chip->writebuf_cur = (chip->writebuf_cur + 1) % YMPSG_WRITEBUF_SIZE;
+        }
+        chip->writebuf_samplecnt++;
+    }
+    out = YMPSG_GetOutput(chip);
+    *buf = (int32_t)(out * 8192.f);
+}
+
+void YMPSG_WriteBuffered(ympsg_t *chip, uint8_t data)
+{
+    uint64_t time1, time2;
+    uint64_t skip;
+
+    if (chip->writebuf[chip->writebuf_last].stat)
+    {
+        YMPSG_Write(chip, chip->writebuf[chip->writebuf_last].data);
+
+        chip->writebuf_cur = (chip->writebuf_last + 1) % YMPSG_WRITEBUF_SIZE;
+        skip = chip->writebuf[chip->writebuf_last].time - chip->writebuf_samplecnt;
+        chip->writebuf_samplecnt = chip->writebuf[chip->writebuf_last].time;
+        while (skip--)
+        {
+            YMPSG_Clock(chip);
+        }
+    }
+
+    chip->writebuf[chip->writebuf_last].stat = 1;
+    chip->writebuf[chip->writebuf_last].data = data;
+    time1 = chip->writebuf_lasttime + YMPSG_WRITEBUF_DELAY;
+    time2 = chip->writebuf_samplecnt;
+
+    if (time1 < time2)
+    {
+        time1 = time2;
+    }
+
+    chip->writebuf[chip->writebuf_last].time = time1;
+    chip->writebuf_lasttime = time1;
+    chip->writebuf_last = (chip->writebuf_last + 1) % YMPSG_WRITEBUF_SIZE;
+}
+
+void YMPSG_SetMute(ympsg_t *chip, uint8_t mute)
+{
+    chip->mute = mute;
+}

extern/Nuked-PSG/ympsg.h

@@ -0,0 +1,77 @@
+// Copyright (C) 2021 Nuke.YKT
+// License: GPLv2+
+// Version 1.0.1
+#ifndef _YMPSG_H_
+#define _YMPSG_H_
+#include <stdint.h>
+
+#define YMPSG_WRITEBUF_SIZE 2048
+#define YMPSG_WRITEBUF_DELAY 8
+
+typedef struct _ympsg_writebuf {
+    uint64_t time;
+    uint8_t stat;
+    uint8_t data;
+} ympsg_writebuf;
+
+typedef struct {
+    // IO
+    uint8_t data;
+    uint8_t latch;
+    uint8_t write_flag;
+    uint8_t write_flag_l;
+
+    uint8_t prescaler_1;
+    uint8_t prescaler_2;
+    uint8_t prescaler_2_l;
+    uint8_t reset_latch;
+    uint8_t ic;
+    uint8_t ic_latch1;
+    uint8_t ic_latch2;
+    uint8_t data_mask;
+    uint8_t reg_reset;
+    uint8_t volume[4];
+    uint16_t freq[3];
+    uint8_t noise_data;
+    uint8_t noise_of;
+    uint8_t noise_trig;
+    uint8_t noise_trig_l;
+    uint8_t rot;
+
+    uint8_t chan_sel;
+
+    uint16_t counter[4];
+    uint8_t counter_of;
+    uint8_t sign;
+    uint8_t sign_l;
+    uint8_t noise_sign_l;
+    uint16_t noise;
+    uint8_t test;
+    uint8_t volume_out[4];
+
+    //
+    uint64_t writebuf_samplecnt;
+    uint32_t writebuf_cur;
+    uint32_t writebuf_last;
+    uint64_t writebuf_lasttime;
+    ympsg_writebuf writebuf[YMPSG_WRITEBUF_SIZE];
+
+    uint8_t mute;
+} ympsg_t;
+
+
+void YMPSG_Write(ympsg_t *chip, uint8_t data);
+uint16_t YMPSG_Read(ympsg_t *chip);
+void YMPSG_Init(ympsg_t *chip);
+void YMPSG_SetIC(ympsg_t *chip, uint32_t ic);
+void YMPSG_Clock(ympsg_t *chip);
+float YMPSG_GetOutput(ympsg_t *chip);
+void YMPSG_Test(ympsg_t *chip, uint16_t test);
+
+
+void YMPSG_Generate(ympsg_t *chip, int32_t *buf);
+void YMPSG_WriteBuffered(ympsg_t *chip, uint8_t data);
+
+void YMPSG_SetMute(ympsg_t *chip, uint8_t mute);
+
+#endif

src/engine/dispatchContainer.cpp

@@ -191,6 +191,7 @@ void DivDispatchContainer::init(DivSystem sys, DivEngine* eng, int chanCount, do
       break;
     case DIV_SYSTEM_SMS:
       dispatch=new DivPlatformSMS;
+      ((DivPlatformSMS*)dispatch)->setNuked(eng->getConfInt("snCore",0));
       break;
     case DIV_SYSTEM_GB:
       dispatch=new DivPlatformGB;

src/engine/platform/sms.cpp

@@ -21,7 +21,7 @@
 #include "../engine.h"
 #include <math.h>
 
-#define rWrite(v) {if (!skipRegisterWrites) {sn->write(v); if (dumpWrites) {addWrite(0x200,v);}}}
+#define rWrite(v) {if (!skipRegisterWrites) {writes.push(v); if (dumpWrites) {addWrite(0x200,v);}}}
 
 const char* regCheatSheetSN[]={
   "DATA", "0",
@@ -41,7 +41,47 @@ const char* DivPlatformSMS::getEffectName(unsigned char effect) {
   return NULL;
 }
 
-void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+void DivPlatformSMS::acquire_nuked(short* bufL, short* bufR, size_t start, size_t len) {
+  for (size_t h=start; h<start+len; h++) {
+    if (!writes.empty()) {
+      unsigned char w=writes.front();
+      YMPSG_Write(&sn_nuked,w);
+      writes.pop();
+    }
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    YMPSG_Clock(&sn_nuked);
+    bufL[h]=YMPSG_GetOutput(&sn_nuked)*8192.0;
+    /*
+    for (int i=0; i<4; i++) {
+      if (isMuted[i]) {
+        oscBuf[i]->data[oscBuf[i]->needle++]=0;
+      } else {
+        oscBuf[i]->data[oscBuf[i]->needle++]=sn->get_channel_output(i);
+      }
+    }*/
+  }
+}
+
+void DivPlatformSMS::acquire_mame(short* bufL, short* bufR, size_t start, size_t len) {
+  while (!writes.empty()) {
+    unsigned char w=writes.front();
+    sn->write(w);
+    writes.pop();
+  }
   for (size_t h=start; h<start+len; h++) {
     sn->sound_stream_update(bufL+h,1);
     for (int i=0; i<4; i++) {
@@ -54,6 +94,14 @@ void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len)
   }
 }
 
+void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+  if (nuked) {
+    acquire_nuked(bufL,bufR,start,len);
+  } else {
+    acquire_mame(bufL,bufR,start,len);
+  }
+}
+
 int DivPlatformSMS::acquireOne() {
   short v;
   sn->sound_stream_update(&v,1);
@@ -301,6 +349,7 @@ DivDispatchOscBuffer* DivPlatformSMS::getOscBuffer(int ch) {
 }
 
 void DivPlatformSMS::reset() {
+  while (!writes.empty()) writes.pop();
   for (int i=0; i<4; i++) {
     chan[i]=DivPlatformSMS::Channel();
     chan[i].std.setEngine(parent);
@@ -309,6 +358,7 @@ void DivPlatformSMS::reset() {
     addWrite(0xffffffff,0);
   }
   sn->device_start();
+  YMPSG_Init(&sn_nuked);
   snNoiseMode=3;
   rWrite(0xe7);
   updateSNMode=false;
@@ -352,6 +402,7 @@ void DivPlatformSMS::setFlags(unsigned int flags) {
     chipClock=COLOR_NTSC;
   }
   resetPhase=!(flags&16);
+  
   if (sn!=NULL) delete sn;
   switch ((flags>>2)&3) {
     case 1: // TI
@@ -377,6 +428,10 @@ void DivPlatformSMS::setFlags(unsigned int flags) {
   }
 }
 
+void DivPlatformSMS::setNuked(bool value) {
+  nuked=value;
+}
+
 int DivPlatformSMS::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
   parent=p;
   dumpWrites=false;

src/engine/platform/sms.h

@@ -23,6 +23,10 @@
 #include "../dispatch.h"
 #include "../macroInt.h"
 #include "sound/sn76496.h"
+extern "C" {
+  #include "../../../extern/Nuked-PSG/ympsg.h"
+}
+#include <queue>
 
 class DivPlatformSMS: public DivDispatch {
   struct Channel {
@@ -59,8 +63,14 @@ class DivPlatformSMS: public DivDispatch {
   bool updateSNMode;
   bool resetPhase;
   bool isRealSN;
+  bool nuked;
   sn76496_base_device* sn;
+  ympsg_t sn_nuked;
+  std::queue<unsigned char> writes;
   friend void putDispatchChan(void*,int,int);
+
+  void acquire_nuked(short* bufL, short* bufR, size_t start, size_t len);
+  void acquire_mame(short* bufL, short* bufR, size_t start, size_t len);
   public:
     int acquireOne();
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
@@ -80,6 +90,7 @@ class DivPlatformSMS: public DivDispatch {
     void poke(std::vector<DivRegWrite>& wlist);
     const char** getRegisterSheet();
     const char* getEffectName(unsigned char effect);
+    void setNuked(bool value);
     int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
     void quit();
     ~DivPlatformSMS();

src/gui/gui.h

@@ -864,6 +864,7 @@ class FurnaceGUI {
     int audioQuality;
     int arcadeCore;
     int ym2612Core;
+    int snCore;
     int saaCore;
     int nesCore;
     int fdsCore;
@@ -958,6 +959,7 @@ class FurnaceGUI {
       audioQuality(0),
       arcadeCore(0),
       ym2612Core(0),
+      snCore(0),
       saaCore(1),
       nesCore(0),
       fdsCore(0),

src/gui/settings.cpp

@@ -79,6 +79,11 @@ const char* ym2612Cores[]={
   "ymfm"
 };
 
+const char* snCores[]={
+  "MAME",
+  "Nuked-PSG Mod"
+};
+
 const char* saaCores[]={
   "MAME",
   "SAASound"
@@ -872,6 +877,10 @@ void FurnaceGUI::drawSettings() {
           ImGui::SameLine();
           ImGui::Combo("##YM2612Core",&settings.ym2612Core,ym2612Cores,2);
 
+          ImGui::Text("SN76489 core");
+          ImGui::SameLine();
+          ImGui::Combo("##SNCore",&settings.snCore,snCores,2);
+
           ImGui::Text("SAA1099 core");
           ImGui::SameLine();
           ImGui::Combo("##SAACore",&settings.saaCore,saaCores,2);
@@ -1889,6 +1898,7 @@ void FurnaceGUI::syncSettings() {
   settings.audioRate=e->getConfInt("audioRate",44100);
   settings.arcadeCore=e->getConfInt("arcadeCore",0);
   settings.ym2612Core=e->getConfInt("ym2612Core",0);
+  settings.snCore=e->getConfInt("snCore",0);
   settings.saaCore=e->getConfInt("saaCore",1);
   settings.nesCore=e->getConfInt("nesCore",0);
   settings.fdsCore=e->getConfInt("fdsCore",0);
@@ -1975,6 +1985,7 @@ void FurnaceGUI::syncSettings() {
   clampSetting(settings.audioRate,8000,384000);
   clampSetting(settings.arcadeCore,0,1);
   clampSetting(settings.ym2612Core,0,1);
+  clampSetting(settings.snCore,0,1);
   clampSetting(settings.saaCore,0,1);
   clampSetting(settings.nesCore,0,1);
   clampSetting(settings.fdsCore,0,1);
@@ -2089,6 +2100,7 @@ void FurnaceGUI::commitSettings() {
   e->setConf("audioRate",settings.audioRate);
   e->setConf("arcadeCore",settings.arcadeCore);
   e->setConf("ym2612Core",settings.ym2612Core);
+  e->setConf("snCore",settings.snCore);
   e->setConf("saaCore",settings.saaCore);
   e->setConf("nesCore",settings.nesCore);
   e->setConf("fdsCore",settings.fdsCore);