mednafen debugger mute sound channel PCE patch

diff --git a/src/debug.h b/src/debug.h
index 6e101a6..75d9502 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -174,7 +174,7 @@ typedef struct
  void (*SetGraphicsDecode)(MDFN_Surface *surface, int line, int which, int xscroll, int yscroll, int pbn);

  void (*SetLogFunc)(void (*logfunc)(const char *type, const char *text));
-
+ void (*MuteChannel)(uint8 chan);
  // Game emulation code shouldn't touch these directly.
  std::vector<AddressSpaceType> *AddressSpaces;
  std::vector<RegGroupType*> *RegGroups;
diff --git a/src/drivers/debugger.cpp b/src/drivers/debugger.cpp
index 1cf404c..a8da6e0 100644
--- a/src/drivers/debugger.cpp
+++ b/src/drivers/debugger.cpp
@@ -1486,6 +1486,29 @@ void Debugger_GT_Event(const SDL_Event *event)
      default: break;
     }
    }
+   else if(event->key.keysym.mod & KMOD_SHIFT)
+   {
+    switch(event->key.keysym.sym)
+    {
+     if (CurGame->Debugger->MuteChannel)
+     {
+      case SDLK_1: CurGame->Debugger->MuteChannel(0);
+       break;
+      case SDLK_2: CurGame->Debugger->MuteChannel(1);
+       break;
+      case SDLK_3: CurGame->Debugger->MuteChannel(2);
+       break;
+      case SDLK_4: CurGame->Debugger->MuteChannel(3);
+       break;
+      case SDLK_5: CurGame->Debugger->MuteChannel(4);
+       break;
+      case SDLK_6: CurGame->Debugger->MuteChannel(5);
+       break;
+     }
+
+     default: break;
+    }
+   }
   }

   if(WhichMode == 1)
diff --git a/src/hw_sound/pce_psg/pce_psg.cpp b/src/hw_sound/pce_psg/pce_psg.cpp
index 8217bdf..d6afcbf 100644
--- a/src/hw_sound/pce_psg/pce_psg.cpp
+++ b/src/hw_sound/pce_psg/pce_psg.cpp
@@ -291,6 +291,16 @@ uint32 PCE_PSG::GetRegister(const unsigned int id, char *special, const uint32 s
  return(value);
 }

+void PCE_PSG::MuteChannel(uint8 chan)
+{
+  uint32 val = 0;
+  if (channel_mute & (1<<chan))
+    val = 0xFF;
+  channel[chan].balance = val & 0xFF;
+  //SetRegister(PSG_GSREG_CH0_BALANCE | (channel << 8), 0);
+  channel_mute ^= (1<<chan);
+}
+

 void PCE_PSG::SetRegister(const unsigned int id, const uint32 value)
 {
@@ -333,7 +343,8 @@ void PCE_PSG::SetRegister(const unsigned int id, const uint32 value)
    break;

   case PSG_GSREG_CH0_BALANCE:
-   channel[ch].balance = value & 0xFF;
+  if (!(channel_mute & (1<<ch)))
+    channel[ch].balance = value & 0xFF;
    break;

   case PSG_GSREG_CH0_WINDEX:
@@ -434,6 +445,8 @@ PCE_PSG::PCE_PSG(int32* hr_l, int32* hr_r, int want_revision)
     channel[ch].lastts = 0;
    }

+  channel_mute = 0;
+
    SetVolume(1.0); // Will build dbtable in the process.
    Power(0);
 }
@@ -531,7 +544,8 @@ void PCE_PSG::Write(int32 timestamp, uint8 A, uint8 V)

         case 0x05: /* Channel balance */
        if(select > 5) return; // no more than 6 channels, silly game.
-            ch->balance = V;
+            if (!(channel_mute & (1<<select)))
+              ch->balance = V;

        vol_pending = true;
             break;
diff --git a/src/hw_sound/pce_psg/pce_psg.h b/src/hw_sound/pce_psg/pce_psg.h
index 4405ac3..af471b3 100644
--- a/src/hw_sound/pce_psg/pce_psg.h
+++ b/src/hw_sound/pce_psg/pce_psg.h
@@ -129,6 +129,8 @@ class PCE_PSG
         PCE_PSG(int32* hr_l, int32* hr_r, int want_revision);
         ~PCE_PSG();

+        void MuteChannel(const uint8 chan);
+
    void StateAction(StateMem *sm, const unsigned load, const bool data_only);

         void Power(const int32 timestamp);
@@ -166,6 +168,7 @@ class PCE_PSG
    void RecalcNoiseFreqCache(int chnum);
    void RunChannel(int chc, int32 timestamp, bool LFO_On);

+        uint8 channel_mute;         /* bit flags */
         uint8 select;               /* Selected channel (0-5) */
         uint8 globalbalance;        /* Global sound balance */
         uint8 lfofreq;              /* LFO frequency */
diff --git a/src/pce/debug.cpp b/src/pce/debug.cpp
index 1021b11..4f0712e 100644
--- a/src/pce/debug.cpp
+++ b/src/pce/debug.cpp
@@ -1116,6 +1116,7 @@ DebuggerInfoStruct PCEDBGInfo =
  GetBranchTrace,
  SetGraphicsDecode,
  PCEDBG_SetLogFunc,
+ PCEDBG_MuteChannel,
 };

 static void Cleanup(void)
@@ -1127,6 +1128,11 @@ static void Cleanup(void)
  }
 }

+void PCEDBG_MuteChannel(uint8 chan)
+{
+  psg->MuteChannel(chan);
+}
+
 void PCEDBG_Kill(void)
 {
  Cleanup();
diff --git a/src/pce/debug.h b/src/pce/debug.h
index 792b855..14bf4c1 100644
--- a/src/pce/debug.h
+++ b/src/pce/debug.h
@@ -7,7 +7,7 @@

 namespace MDFN_IEN_PCE
 {
-
+void PCEDBG_MuteChannel(uint8 channel);
 void PCEDBG_MachineStateChanged(void);

 void PCEDBG_FlushBreakPoints(int type);