From 8b879053047383cf86b942b27dfe7280ccccf1bd Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Tue, 11 Oct 2022 03:52:25 -0500
Subject: [PATCH] Virtual Boy: fix noise phase reset

---
 src/engine/platform/vb.cpp |  8 +++++---
 src/engine/platform/vb.h   |  2 +-
 src/gui/presets.cpp        | 12 ++++++++++++
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/engine/platform/vb.cpp b/src/engine/platform/vb.cpp
index dfb79348..ddc1e568 100644
--- a/src/engine/platform/vb.cpp
+++ b/src/engine/platform/vb.cpp
@@ -128,9 +128,11 @@ void DivPlatformVB::updateWave(int ch) {
   }
 }
 
-void DivPlatformVB::writeEnv(int ch) {
+void DivPlatformVB::writeEnv(int ch, bool upperByteToo) {
   chWrite(ch,0x04,(chan[ch].outVol<<4)|(chan[ch].envLow&15));
-  chWrite(ch,0x05,chan[ch].envHigh);
+  if (ch<5 || upperByteToo) {
+    chWrite(ch,0x05,chan[ch].envHigh);
+  }
 }
 
 void DivPlatformVB::tick(bool sysTick) {
@@ -298,7 +300,7 @@ int DivPlatformVB::dispatch(DivCommand c) {
       if (c.chan!=5) break;
       chan[c.chan].envHigh&=~0x70;
       chan[c.chan].envHigh|=(c.value&7)<<4;
-      writeEnv(c.chan);
+      writeEnv(c.chan,true);
       break;
     case DIV_CMD_STD_NOISE_FREQ:
       chan[c.chan].envHigh&=~3;
diff --git a/src/engine/platform/vb.h b/src/engine/platform/vb.h
index af3ef6dc..baefc03f 100644
--- a/src/engine/platform/vb.h
+++ b/src/engine/platform/vb.h
@@ -81,7 +81,7 @@ class DivPlatformVB: public DivDispatch {
   VSU* vb;
   unsigned char regPool[0x600];
   void updateWave(int ch);
-  void writeEnv(int ch);
+  void writeEnv(int ch, bool upperByteToo=false);
   friend void putDispatchChip(void*,int);
   friend void putDispatchChan(void*,int,int);
   public:
diff --git a/src/gui/presets.cpp b/src/gui/presets.cpp
index f78f7514..a8c49703 100644
--- a/src/gui/presets.cpp
+++ b/src/gui/presets.cpp
@@ -438,6 +438,12 @@ void FurnaceGUI::initSystemPresets() {
       0
     }
   ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "Virtual Boy", {
+      DIV_SYSTEM_VBOY, 64, 0, 0,
+      0
+    }
+  ));
   cat.systems.push_back(FurnaceGUISysDef(
     "Seta/Allumer X1-010", {
       DIV_SYSTEM_X1_010, 64, 0, 0,
@@ -704,6 +710,12 @@ void FurnaceGUI::initSystemPresets() {
       0
     }
   ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "Virtual Boy", {
+      DIV_SYSTEM_VBOY, 64, 0, 0,
+      0
+    }
+  ));
   cat.systems.push_back(FurnaceGUISysDef(
     "Gamate", {
       DIV_SYSTEM_AY8910, 64, 0, 73,