Add Sound Channel toggle for PC Speaker sound

3 files changed, 81 insertions, 25 deletions

diff --git a/Load.HC b/Load.HC
index a70ed1b..fb55fad 100644
--- a/Load.HC
+++ b/Load.HC
@@ -10,6 +10,12 @@ I64 obp03,obp02,obp01,obp00;
 I64 obp13,obp12,obp11,obp10;
 I64 jp_state[8];
 
+I64 apuCtr=0;
+I64 apuToggle=1;
+I64 kAPUChan1=0;
+I64 kAPUChan2=0;
+I64 kAPUChan3=0;
+
 I64 kLoad=0;
 I64 kReset=0;
 I64 kSave=0;
@@ -1018,6 +1024,17 @@ U0 runInterrupt()
 
 U0 updateCore()
 {
+    if (apuToggle==1)
+    {
+      apuCtr++;
+      if(apuCtr>1000)
+      {
+        memory[0xFEED]++;
+        if(memory[0xFEED]>1) { memory[0xFEED]=0; };
+        apuCtr=0;
+      };
+    };
+
     // DIV control
     DIVTicks += CPUTicks;
     if (DIVTicks >= 0x40) {
@@ -1118,6 +1135,45 @@ U0 executeIteration()
         //Keyboard
         
         switch(sc) {
+
+            case 0x10:
+                kAPUChan1=0;
+                break;
+            case 0x10 + 0x80:
+                if(!kAPUChan1) {
+                  kAPUChan1=1;
+                  apuToggle=0;
+                  memory[0xFEED]=0;
+                  StrCpy(DisplayMsg,"APU Ch 01");
+                  DisplayMsgTicks=1;
+                };
+                break;
+
+            case 0x11:
+                kAPUChan2=0;
+                break;
+            case 0x11 + 0x80:
+                if(!kAPUChan2) {
+                  kAPUChan2=1;
+                  apuToggle=0;
+                  memory[0xFEED]=1;
+                  StrCpy(DisplayMsg,"APU Ch 02");
+                  DisplayMsgTicks=1;
+                };
+                break;
+
+            case 0x12:
+                kAPUChan3=0;
+                break;
+            case 0x12 + 0x80:
+                if(!kAPUChan3) {
+                  kAPUChan3=1;
+                  apuToggle=1;
+                  StrCpy(DisplayMsg,"APU Ch Auto");
+                  DisplayMsgTicks=1;
+                };
+                break;
+
             case 0x13:
                 kReset=0;
                 break;
@@ -1302,6 +1358,7 @@ U0 start()
     initCart; // init cartridge bank type
     setupRAMBanks;
     initLCD; // init LCD
+    memory[0xFEED]=1;
     CTask *snd_task=Spawn(&GBSoundTask,&memory,,2);
     // BG Palette $$FF47 
     SetPal(memory[0xFF47],&bgp0,&bgp1,&bgp2,&bgp3);
diff --git a/README.md b/README.md
index 1eca7dd..ac831f4 100644
--- a/README.md
+++ b/README.md
@@ -31,3 +31,9 @@ Load State: `5`
 
 Save State: `7`
 
+Sound Channel 1: `Q`
+
+Sound Channel 2: `W`
+
+Sound Channel Auto Toggle: `E`
+
diff --git a/Sound.HC b/Sound.HC
index 0fd9a31..45dd9e8 100755
--- a/Sound.HC
+++ b/Sound.HC
@@ -1,45 +1,45 @@
-
 U0 GBSoundTask(U8 *regs)
 {
-
-  I64 ch=0;
-  I64 chP=0;
   I64 div;
   I64 freq;
   I64 x;
-  I64 prevX;
+
+  I64 prevA=0;
+  I64 prevB=0;
+
   while (TRUE)
   {
-    if(ch==0 && chP==FALSE)
-    {
-    
+
+    if(memory[0xFEED]==0)
+    {   
       if (memory[0xFF12]>0b10000)
       {
         x = memory[0xFF13];
         x += ((memory[0xFF14] & 0b00000111)<<8);
-        if (x!=prevX)
+        if (x!=prevA)
         {
           freq=131072/(2048-x);
           div=1193180/freq;
+          // I wanted to use Snd(Freq2Ona(freq)); here
+          // instead of I/O port writes, but the 
+          // conversion isn't right...?
           OutU8(0x43, 0xB6);
           OutU8(0x42, div);
           OutU8(0x42, div>>8);
           OutU8(0x61,3|InU8(0x61));
-          prevX=x;
+          prevA=x;
         };
       } else {
-        //SndRst;
-      }
+      };
     };
 
-    if(ch==1)
-    {
-    
+    if(memory[0xFEED]==1)
+    {   
       if (memory[0xFF17]>0b10000)
       {
         x = memory[0xFF18];
         x += ((memory[0xFF19] & 0b00000111)<<8);
-        if (x!=prevX)
+        if (x!=prevB)
         {
           freq=131072/(2048-x);
           div=1193180/freq;
@@ -47,19 +47,12 @@ U0 GBSoundTask(U8 *regs)
           OutU8(0x42, div);
           OutU8(0x42, div>>8);
           OutU8(0x61,3|InU8(0x61));
-          prevX=x;
-          chP=TRUE;
+          prevB=x;
         };
       } else {
-        chP=FALSE;
-      }
+      };
     };
 
-
-
     Sleep(2);
-
-  ch++;
-  if (ch>3) { ch=0; };
   };
 }