From f62f6ed77bbef759cc2cc4ecb28863b97b7e3134 Mon Sep 17 00:00:00 2001
From: cam900 <dbtlrchl@naver.com>
Date: Sun, 15 May 2022 00:58:00 +0900
Subject: [PATCH] Fix AY VGM output, Fix presets

---
 src/engine/vgmOps.cpp | 35 +++++++++++++++++++++++++++++++++--
 src/gui/presets.cpp   |  3 ++-
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/src/engine/vgmOps.cpp b/src/engine/vgmOps.cpp
index 53eddc1b2..2916c1034 100644
--- a/src/engine/vgmOps.cpp
+++ b/src/engine/vgmOps.cpp
@@ -906,11 +906,41 @@ SafeWriter* DivEngine::saveVGM(bool* sysToExport, bool loop, int version) {
         }
         break;
       case DIV_SYSTEM_AY8910:
-      case DIV_SYSTEM_AY8930:
+      case DIV_SYSTEM_AY8930: {
         if (!hasAY) {
+          bool hasClockDivider=false; // Configurable clock divider
+          bool hasStereo=true; // Stereo
           hasAY=disCont[i].dispatch->chipClock;
-          ayConfig=(song.system[i]==DIV_SYSTEM_AY8930)?3:0;
           ayFlags=1;
+          if (song.system[i]==DIV_SYSTEM_AY8930) { // AY8930
+            ayConfig=0x03;
+            hasClockDivider=true;
+          } else {
+            switch ((song.systemFlags[i]>>4)&3) {
+              default:
+              case 0: // AY8910
+                ayConfig=0x00;
+                break;
+              case 1: // YM2149
+                ayConfig=0x10;
+                hasClockDivider=true;
+                break;
+              case 2: // Sunsoft 5B
+                ayConfig=0x10;
+                ayFlags|=0x12; // Clock internally divided, Single sound output
+                hasStereo=false; // due to above, can't be per-channel stereo configurable
+                break;
+              case 3: // AY8914
+                ayConfig=0x04;
+                break;
+            }
+          }
+          if (hasClockDivider && ((song.systemFlags[i]>>7)&1)) {
+            ayFlags|=0x10;
+          }
+          if (hasStereo && ((song.systemFlags[i]>>6)&1)) {
+            ayFlags|=0x80;
+          }
           willExport[i]=true;
         } else if (!(hasAY&0x40000000)) {
           isSecond[i]=true;
@@ -919,6 +949,7 @@ SafeWriter* DivEngine::saveVGM(bool* sysToExport, bool loop, int version) {
           howManyChips++;
         }
         break;
+      }
       case DIV_SYSTEM_SAA1099:
         if (!hasSAA) {
           hasSAA=disCont[i].dispatch->chipClock;
diff --git a/src/gui/presets.cpp b/src/gui/presets.cpp
index 021f13480..d04d329d7 100644
--- a/src/gui/presets.cpp
+++ b/src/gui/presets.cpp
@@ -647,11 +647,12 @@ void FurnaceGUI::initSystemPresets() {
     "MSX + Darky", {
       DIV_SYSTEM_AY8910, 64, 0, 16,
       DIV_SYSTEM_AY8930, 64, 0, 139, // 3.58MHz
-      DIV_SYSTEM_AY8930, 64, 0, 140, // 3.58MHz or 3.6MHz selectable via register
+      DIV_SYSTEM_AY8930, 64, 0, 139, // 3.58MHz or 3.6MHz selectable via register
       // per-channel mixer (soft panning, post processing) isn't emulated at all
       0
     }
   ));
+  cat.systems.push_back(FurnaceGUISysDef(
     "MSX + SCC", {
       DIV_SYSTEM_AY8910, 64, 0, 16,
       DIV_SYSTEM_SCC, 64, 0, 0,