From 6dc01159ee076ba757c677442cd0605725d69cd9 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 28 Feb 2022 01:25:10 -0500
Subject: [PATCH] OPLL: 88%

TODO:
- effects
- FM macros (ugh)
- muting
- proper drum mode
- proper VRC7
---
 src/engine/platform/opll.cpp | 51 ++++++++++++++++++++++++------------
 src/engine/platform/opll.h   |  4 +--
 2 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/src/engine/platform/opll.cpp b/src/engine/platform/opll.cpp
index 28285931..a9f98b53 100644
--- a/src/engine/platform/opll.cpp
+++ b/src/engine/platform/opll.cpp
@@ -241,7 +241,7 @@ void DivPlatformOPLL::tick() {
     }*/
 
     if (chan[i].keyOn || chan[i].keyOff) {
-      if (chan[i].drums) {
+      if (i>=6 && drums) {
         drumState&=~(0x10>>(chan[i].note%12));
         immWrite(0x0e,0x20|drumState);
       } else {
@@ -266,11 +266,11 @@ void DivPlatformOPLL::tick() {
       int freqt=toFreq(chan[i].freq);
       chan[i].freqH=freqt>>8;
       chan[i].freqL=freqt&0xff;
-      if (!chan[i].drums) {
+      if (i<6 || !drums) {
         immWrite(0x10+i,freqt&0xff);
       }
     }
-    if (chan[i].keyOn && chan[i].drums) {
+    if (chan[i].keyOn && i>=6 && drums) {
       //printf("%d\n",chan[i].note%12);
       drumState|=(0x10>>(chan[i].note%12));
       immWrite(0x0e,0x20|drumState);
@@ -374,19 +374,24 @@ int DivPlatformOPLL::dispatch(DivCommand c) {
           rWrite(0x07,(car.sl<<4)|(car.rr));
         }
         if (chan[c.chan].state.opllPreset==16) { // compatible drums mode
-          chan[c.chan].drums=true;
-          immWrite(0x16,0x20);
-          immWrite(0x26,0x05);
-          immWrite(0x16,0x20);
-          immWrite(0x26,0x05);
-          immWrite(0x17,0x50);
-          immWrite(0x27,0x05);
-          immWrite(0x17,0x50);
-          immWrite(0x27,0x05);
-          immWrite(0x18,0xC0);
-          immWrite(0x28,0x01);
+          if (c.chan>=6) {
+            drums=true;
+            immWrite(0x16,0x20);
+            immWrite(0x26,0x05);
+            immWrite(0x16,0x20);
+            immWrite(0x26,0x05);
+            immWrite(0x17,0x50);
+            immWrite(0x27,0x05);
+            immWrite(0x17,0x50);
+            immWrite(0x27,0x05);
+            immWrite(0x18,0xC0);
+            immWrite(0x28,0x01);
+          }
         } else {
-          chan[c.chan].drums=false;
+          if (c.chan>=6) {
+            drums=false;
+            immWrite(0x0e,0);
+          }
           rWrite(0x30+c.chan,(15-(chan[c.chan].outVol*(15-chan[c.chan].state.op[1].tl))/15)|(chan[c.chan].state.opllPreset<<4));
         }
       }
@@ -397,7 +402,7 @@ int DivPlatformOPLL::dispatch(DivCommand c) {
         chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value);
         chan[c.chan].note=c.value;
 
-        if (chan[c.chan].drums) {
+        if (c.chan>=6 && drums) {
           switch (chan[c.chan].note%12) {
             case 0: // kick
               drumVol[0]=(15-(chan[c.chan].outVol*(15-chan[c.chan].state.op[1].tl))/15);
@@ -444,7 +449,7 @@ int DivPlatformOPLL::dispatch(DivCommand c) {
       if (!chan[c.chan].std.hasVol) {
         chan[c.chan].outVol=c.value;
       }
-      if (!chan[c.chan].drums) {
+      if (c.chan<6 || !drums) {
         rWrite(0x30+c.chan,(15-(chan[c.chan].outVol*(15-chan[c.chan].state.op[1].tl))/15)|(chan[c.chan].state.opllPreset<<4));
       }
       break;
@@ -587,6 +592,18 @@ void DivPlatformOPLL::forceIns() {
       chan[i].freqChanged=true;
     }
   }
+  if (drums) {
+    immWrite(0x16,0x20);
+    immWrite(0x26,0x05);
+    immWrite(0x16,0x20);
+    immWrite(0x26,0x05);
+    immWrite(0x17,0x50);
+    immWrite(0x27,0x05);
+    immWrite(0x17,0x50);
+    immWrite(0x27,0x05);
+    immWrite(0x18,0xC0);
+    immWrite(0x28,0x01);
+  }
 }
 
 void DivPlatformOPLL::toggleRegisterDump(bool enable) {
diff --git a/src/engine/platform/opll.h b/src/engine/platform/opll.h
index 5db8e26a..415cda8a 100644
--- a/src/engine/platform/opll.h
+++ b/src/engine/platform/opll.h
@@ -35,7 +35,7 @@ class DivPlatformOPLL: public DivDispatch {
       unsigned char freqH, freqL;
       int freq, baseFreq, pitch, note;
       unsigned char ins;
-      bool active, insChanged, freqChanged, keyOn, keyOff, drums, portaPause, furnaceDac, inPorta;
+      bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, furnaceDac, inPorta;
       int vol, outVol;
       unsigned char pan;
       Channel():
@@ -51,7 +51,6 @@ class DivPlatformOPLL: public DivDispatch {
         freqChanged(false),
         keyOn(false),
         keyOff(false),
-        drums(false),
         portaPause(false),
         furnaceDac(false),
         inPorta(false),
@@ -76,6 +75,7 @@ class DivPlatformOPLL: public DivDispatch {
     unsigned char regPool[256];
 
     bool useYMFM;
+    bool drums;
   
     short oldWrites[256];
     short pendingWrites[256];