From 0d4f20b7a6f500bfbd7731169421a0eeac0bf608 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Wed, 3 Aug 2022 00:05:58 -0500
Subject: [PATCH] SoundUnit: add 64K chip revision

---
 src/engine/platform/sound/su.cpp | 16 ++++++++--------
 src/engine/platform/sound/su.h   |  7 +++----
 src/engine/platform/su.cpp       | 11 ++++++++---
 src/engine/platform/su.h         |  1 +
 src/gui/sysConf.cpp              | 17 +++++++++++++++++
 5 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/engine/platform/sound/su.cpp b/src/engine/platform/sound/su.cpp
index b7fa731a..0dd6dcdc 100644
--- a/src/engine/platform/sound/su.cpp
+++ b/src/engine/platform/sound/su.cpp
@@ -54,7 +54,7 @@ void SoundUnit::NextSample(short* l, short* r) {
               chan[i].pcmpos=chan[i].pcmrst;
             }
           }
-          chan[i].pcmpos&=(SOUNDCHIP_PCM_SIZE-1);
+          chan[i].pcmpos&=(pcmSize-1);
         } else if (chan[i].flags.pcmloop) {
           chan[i].pcmpos=chan[i].pcmrst;
         }
@@ -228,9 +228,10 @@ void SoundUnit::NextSample(short* l, short* r) {
   *r=minval(32767,maxval(-32767,tnsR));
 }
 
-void SoundUnit::Init() {
+void SoundUnit::Init(int sampleMemSize) {
+  pcmSize=sampleMemSize;
   Reset();
-  memset(pcm,0,SOUNDCHIP_PCM_SIZE);
+  memset(pcm,0,pcmSize);
   for (int i=0; i<256; i++) {
     SCsine[i]=sin((i/128.0f)*M_PI)*127;
     SCtriangle[i]=(i>127)?(255-i):(i);
@@ -242,9 +243,6 @@ void SoundUnit::Init() {
     SCpantabR[128+i]=i-1;
   }
   SCpantabR[128]=0;
-  for (int i=0; i<8; i++) {
-    muted[i]=false;
-  }
 }
 
 void SoundUnit::Reset() {
@@ -282,6 +280,8 @@ void SoundUnit::Write(unsigned char addr, unsigned char data) {
 }
 
 SoundUnit::SoundUnit() {
-  Init();
-  memset(pcm,0,SOUNDCHIP_PCM_SIZE);
+  Init(65536); // default
+  for (int i=0; i<8; i++) {
+    muted[i]=false;
+  }
 }
diff --git a/src/engine/platform/sound/su.h b/src/engine/platform/sound/su.h
index 3152e856..3b125f03 100644
--- a/src/engine/platform/sound/su.h
+++ b/src/engine/platform/sound/su.h
@@ -3,8 +3,6 @@
 #include <math.h>
 #include <assert.h>
 
-#define SOUNDCHIP_PCM_SIZE 8192
-
 class SoundUnit {
   signed char SCsine[256];
   signed char SCtriangle[256];
@@ -24,6 +22,7 @@ class SoundUnit {
   int tnsL, tnsR;
   unsigned short oldfreq[8];
   unsigned short oldflags[8];
+  unsigned int pcmSize;
   public:
     unsigned short resetfreq[8];
     unsigned short voldcycles[8];
@@ -84,7 +83,7 @@ class SoundUnit {
       unsigned short wc;
       unsigned short restimer;
     } chan[8];
-    signed char pcm[SOUNDCHIP_PCM_SIZE];
+    signed char pcm[65536];
     bool muted[8];
     void Write(unsigned char addr, unsigned char data);
     void NextSample(short* l, short* r);
@@ -94,7 +93,7 @@ class SoundUnit {
       if (ret>32767) ret=32767;
       return ret;
     }
-    void Init();
+    void Init(int sampleMemSize=8192);
     void Reset();
     SoundUnit();
 };
diff --git a/src/engine/platform/su.cpp b/src/engine/platform/su.cpp
index c2cd6b25..2d1a3893 100644
--- a/src/engine/platform/su.cpp
+++ b/src/engine/platform/su.cpp
@@ -555,6 +555,11 @@ void DivPlatformSoundUnit::setFlags(unsigned int flags) {
   for (int i=0; i<8; i++) {
     oscBuf[i]->rate=rate;
   }
+
+  sampleMemSize=flags&16;
+
+  su->Init(sampleMemSize?65536:8192);
+  renderSamples();
 }
 
 void DivPlatformSoundUnit::poke(unsigned int addr, unsigned short val) {
@@ -570,7 +575,7 @@ const void* DivPlatformSoundUnit::getSampleMem(int index) {
 }
 
 size_t DivPlatformSoundUnit::getSampleMemCapacity(int index) {
-  return (index==0)?8192:0;
+  return (index==0)?(sampleMemSize?65536:8192):0;
 }
 
 size_t DivPlatformSoundUnit::getSampleMemUsage(int index) {
@@ -583,6 +588,7 @@ void DivPlatformSoundUnit::renderSamples() {
   size_t memPos=0;
   for (int i=0; i<parent->song.sampleLen; i++) {
     DivSample* s=parent->song.sample[i];
+    if (s->data8==NULL) continue;
     int paddedLen=s->samples;
     if (memPos>=getSampleMemCapacity(0)) {
       logW("out of PCM memory for sample %d!",i);
@@ -609,9 +615,8 @@ int DivPlatformSoundUnit::init(DivEngine* p, int channels, int sugRate, unsigned
     isMuted[i]=false;
     oscBuf[i]=new DivDispatchOscBuffer;
   }
-  setFlags(flags);
   su=new SoundUnit();
-  su->Init();
+  setFlags(flags);
   reset();
   return 6;
 }
diff --git a/src/engine/platform/su.h b/src/engine/platform/su.h
index 1d39854f..e882c398 100644
--- a/src/engine/platform/su.h
+++ b/src/engine/platform/su.h
@@ -96,6 +96,7 @@ class DivPlatformSoundUnit: public DivDispatch {
   };
   std::queue<QueuedWrite> writes;
   unsigned char lastPan;
+  bool sampleMemSize;
 
   int cycles, curChan, delay;
   short tempL;
diff --git a/src/gui/sysConf.cpp b/src/gui/sysConf.cpp
index 36531242..7c624f30 100644
--- a/src/gui/sysConf.cpp
+++ b/src/gui/sysConf.cpp
@@ -120,6 +120,23 @@ void FurnaceGUI::drawSysConf(int chan, DivSystem type, unsigned int& flags, bool
       }
       break;
     }
+    case DIV_SYSTEM_SOUND_UNIT: {
+      ImGui::Text("CPU rate:");
+      if (ImGui::RadioButton("6.18MHz (NTSC)",(flags&15)==0)) {
+        copyOfFlags=(flags&(~15))|0;
+      }
+      if (ImGui::RadioButton("5.95MHz (PAL)",(flags&15)==1)) {
+        copyOfFlags=(flags&(~15))|1;
+      }
+      ImGui::Text("Chip revision (sample memory):");
+      if (ImGui::RadioButton("A/B/E (8K)",(flags&16)==0)) {
+        copyOfFlags=(flags&(~16))|0;
+      }
+      if (ImGui::RadioButton("D/F (64K)",(flags&16)==16)) {
+        copyOfFlags=(flags&(~16))|16;
+      }
+      break;
+    }
     case DIV_SYSTEM_GB: {
       bool antiClick=flags&8;
       if (ImGui::Checkbox("Disable anti-click",&antiClick)) {