From f8796f8ec9d749615e9f9c3dd7bb1477d67083d1 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 28 May 2022 18:15:26 -0500
Subject: [PATCH] MSM6295: VGM export!

---
 src/engine/platform/msm6295.cpp | 29 ++++++++++++++++++--------
 src/engine/platform/msm6295.h   |  1 +
 src/engine/sysDef.cpp           |  2 +-
 src/engine/vgmOps.cpp           | 36 +++++++++++++++++++++++++++++++++
 4 files changed, 59 insertions(+), 9 deletions(-)

diff --git a/src/engine/platform/msm6295.cpp b/src/engine/platform/msm6295.cpp
index 950f80a7..f1d4e997 100644
--- a/src/engine/platform/msm6295.cpp
+++ b/src/engine/platform/msm6295.cpp
@@ -57,7 +57,7 @@ void DivPlatformMSM6295::acquire(short* bufL, short* bufR, size_t start, size_t
           case 11:
             break;
           case 12: // rate select
-            msm->ss_w(w.val);
+            msm->ss_w(!w.val);
             break;
           case 14: // enable bankswitch
             break;
@@ -181,7 +181,7 @@ int DivPlatformMSM6295::dispatch(DivCommand c) {
     }
     case DIV_CMD_SAMPLE_FREQ:
       rateSel=c.value;
-      rWrite(12,rateSel);
+      rWrite(12,!rateSel);
       break;
     case DIV_CMD_SAMPLE_BANK:
       sampleBank=c.value;
@@ -220,7 +220,7 @@ void DivPlatformMSM6295::forceIns() {
   for (int i=0; i<4; i++) {
     chan[i].insChanged=true;
   }
-  rWrite(12,rateSel);
+  rWrite(12,!rateSel);
 }
 
 void* DivPlatformMSM6295::getChanState(int ch) {
@@ -273,6 +273,10 @@ bool DivPlatformMSM6295::keyOffAffectsArp(int ch) {
   return false;
 }
 
+float DivPlatformMSM6295::getPostAmp() {
+  return 3.0f;
+}
+
 void DivPlatformMSM6295::notifyInsChange(int ins) {
   for (int i=0; i<4; i++) {
     if (chan[i].ins==ins) {
@@ -335,12 +339,21 @@ void DivPlatformMSM6295::renderSamples() {
 }
 
 void DivPlatformMSM6295::setFlags(unsigned int flags) {
-  if (flags&1) {
-    chipClock=8448000;
-  } else {
-    chipClock=8000000;
+  switch (flags) {
+    case 0:
+      chipClock=4000000/4;
+      break;
+    case 1:
+      chipClock=4224000/4;
+      break;
+    case 2:
+      chipClock=4000000;
+      break;
+    case 3:
+      chipClock=4224000;
+      break;
   }
-  rate=chipClock/((flags&2)?6:24);
+  rate=chipClock/3;
   for (int i=0; i<4; i++) {
     isMuted[i]=false;
     oscBuf[i]->rate=rate/22;
diff --git a/src/engine/platform/msm6295.h b/src/engine/platform/msm6295.h
index d63a01dc..2930a169 100644
--- a/src/engine/platform/msm6295.h
+++ b/src/engine/platform/msm6295.h
@@ -120,6 +120,7 @@ class DivPlatformMSM6295: public DivDispatch {
     void tick(bool sysTick=true);
     void muteChannel(int ch, bool mute);
     bool keyOffAffectsArp(int ch);
+    float getPostAmp();
     void notifyInsChange(int ins);
     void notifyInsDeletion(void* ins);
     void poke(unsigned int addr, unsigned short val);
diff --git a/src/engine/sysDef.cpp b/src/engine/sysDef.cpp
index 2ef13df2..45fde718 100644
--- a/src/engine/sysDef.cpp
+++ b/src/engine/sysDef.cpp
@@ -1949,7 +1949,7 @@ void DivEngine::registerSystems() {
   );
 
   sysDefs[DIV_SYSTEM_MSM6295]=new DivSysDef(
-    "OKI MSM6295", NULL, 0xaa, 0, 4, false, true, 0, false,
+    "OKI MSM6295", NULL, 0xaa, 0, 4, false, true, 0x161, false,
     "an ADPCM sound chip manufactured by OKI and used in many arcade boards.",
     {"Channel 1", "Channel 2", "Channel 3", "Channel 4"},
     {"CH1", "CH2", "CH3", "CH4"},
diff --git a/src/engine/vgmOps.cpp b/src/engine/vgmOps.cpp
index 0ba6bd28..e2754bb6 100644
--- a/src/engine/vgmOps.cpp
+++ b/src/engine/vgmOps.cpp
@@ -488,6 +488,14 @@ void DivEngine::performVGMWrite(SafeWriter* w, DivSystem sys, DivRegWrite& write
         w->writeC(rf5c68Addr);
         w->writeC(8);
         w->writeC(0xff);
+      case DIV_SYSTEM_MSM6295:
+        w->writeC(0xb8); // disable all channels
+        w->writeC(baseAddr2|0);
+        w->writeC(0x78);
+        w->writeC(0xb8); // select rate
+        w->writeC(baseAddr2|12);
+        w->writeC(1);
+      break;
       default:
         break;
     }
@@ -782,6 +790,11 @@ void DivEngine::performVGMWrite(SafeWriter* w, DivSystem sys, DivRegWrite& write
       w->writeC(write.addr&0xff);
       w->writeC(write.val);
       break;
+    case DIV_SYSTEM_MSM6295:
+      w->writeC(0xb8);
+      w->writeC(baseAddr2|(write.addr&0x7f));
+      w->writeC(write.val);
+      break;
     default:
       logW("write not handled!");
       break;
@@ -907,6 +920,7 @@ SafeWriter* DivEngine::saveVGM(bool* sysToExport, bool loop, int version) {
   DivDispatch* writeQSound[2]={NULL,NULL};
   DivDispatch* writeZ280[2]={NULL,NULL};
   DivDispatch* writeRF5C68[2]={NULL,NULL};
+  DivDispatch* writeMSM6295[2]={NULL,NULL};
 
   for (int i=0; i<song.systemLen; i++) {
     willExport[i]=false;
@@ -1299,6 +1313,19 @@ SafeWriter* DivEngine::saveVGM(bool* sysToExport, bool loop, int version) {
           writeRF5C68[0]=disCont[i].dispatch;
         }
         break;
+      case DIV_SYSTEM_MSM6295:
+        if (!hasOKIM6295) {
+          hasOKIM6295=disCont[i].dispatch->chipClock;
+          willExport[i]=true;
+          writeMSM6295[0]=disCont[i].dispatch;
+        } else if (!(hasOKIM6295&0x40000000)) {
+          isSecond[i]=true;
+          willExport[i]=true;
+          writeMSM6295[1]=disCont[i].dispatch;
+          hasOKIM6295|=0x40000000;
+          howManyChips++;
+        }
+        break;
       default:
         break;
     }
@@ -1645,6 +1672,15 @@ SafeWriter* DivEngine::saveVGM(bool* sysToExport, bool loop, int version) {
       w->writeI(0);
       w->write(writeRF5C68[i]->getSampleMem(),writeRF5C68[i]->getSampleMemUsage());
     }
+    if (writeMSM6295[i]!=NULL && writeMSM6295[i]->getSampleMemUsage()>0) {
+      w->writeC(0x67);
+      w->writeC(0x66);
+      w->writeC(0x8b);
+      w->writeI((writeMSM6295[i]->getSampleMemUsage()+8)|(i*0x80000000));
+      w->writeI(writeMSM6295[i]->getSampleMemCapacity());
+      w->writeI(0);
+      w->write(writeMSM6295[i]->getSampleMem(),writeMSM6295[i]->getSampleMemUsage());
+    }
   }
 
   // initialize streams