diff --git a/src/engine/platform/su.cpp b/src/engine/platform/su.cpp
index 7acab357..2dca4b3c 100644
--- a/src/engine/platform/su.cpp
+++ b/src/engine/platform/su.cpp
@@ -32,6 +32,62 @@ const char** DivPlatformSoundUnit::getRegisterSheet() {
 }
 
 const char* DivPlatformSoundUnit::getEffectName(unsigned char effect) {
+  switch (effect) {
+    case 0x10:
+      return "10xx: Set waveform (0 to 7)";
+      break;
+    case 0x12:
+      return "12xx: Set pulse width (0 to 7F)";
+      break;
+    case 0x13:
+      return "13xx: Set resonance (0 to F)";
+      break;
+    case 0x14:
+      return "14xx: Set filter mode (bit 0: ring mod; bit 1: low pass; bit 2: band pass; bit 3: high pass)";
+      break;
+    case 0x15:
+      return "15xx: Set frequency sweep period low byte";
+      break;
+    case 0x16:
+      return "16xx: Set frequency sweep period high byte";
+      break;
+    case 0x17:
+      return "17xx: Set volume sweep period low byte";
+      break;
+    case 0x18:
+      return "18xx: Set volume sweep period high byte";
+      break;
+    case 0x19:
+      return "19xx: Set cutoff sweep period low byte";
+      break;
+    case 0x1a:
+      return "1Axx: Set cutoff sweep period high byte";
+      break;
+    case 0x1b:
+      return "1Bxx: Set frequency sweep boundary";
+      break;
+    case 0x1c:
+      return "1Cxx: Set volume sweep boundary";
+      break;
+    case 0x1d:
+      return "1Dxx: Set cutoff sweep boundary";
+      break;
+    case 0x20:
+      return "20xx: Toggle frequency sweep (bit 0-6: speed; bit 7: direction is up)";
+      break;
+    case 0x21:
+      return "21xx: Toggle volume sweep (bit 0-4: speed; bit 5: direciton is up; bit 6: loop; bit 7: alternate)";
+      break;
+    case 0x22:
+      return "22xx: Toggle cutoff sweep (bit 0-6: speed; bit 7: direction is up)";
+      break;
+    case 0x40: case 0x41: case 0x42: case 0x43:
+    case 0x44: case 0x45: case 0x46: case 0x47:
+    case 0x48: case 0x49: case 0x4a: case 0x4b:
+    case 0x4c: case 0x4d: case 0x4e: case 0x4f:
+      return "4xxx: Set cutoff (0 to FFF)";
+      break;
+  }
   return NULL;
 }
 
@@ -50,6 +106,12 @@ void DivPlatformSoundUnit::writeControl(int ch) {
   chWrite(ch,0x04,(chan[ch].wave&7)|(chan[ch].pcm<<3)|(chan[ch].control<<4));
 }
 
+void DivPlatformSoundUnit::writeControlUpper(int ch) {
+  chWrite(ch,0x05,((int)chan[ch].phaseReset)|(chan[ch].filterPhaseReset<<1)|(chan[ch].pcmLoop<<2)|(chan[ch].timerSync<<3)|(chan[ch].freqSweep<<4)|(chan[ch].volSweep<<5)|(chan[ch].cutSweep<<6));
+  chan[ch].phaseReset=false;
+  chan[ch].filterPhaseReset=false;
+}
+
 void DivPlatformSoundUnit::tick(bool sysTick) {
   for (int i=0; i<8; i++) {
     chan[i].std.next();
@@ -80,6 +142,10 @@ void DivPlatformSoundUnit::tick(bool sysTick) {
       chan[i].wave=chan[i].std.wave.val&7;
       writeControl(i);
     }
+    if (chan[i].std.phaseReset.had) {
+      chan[i].phaseReset=chan[i].std.phaseReset.val;
+      writeControlUpper(i);
+    }
     if (chan[i].std.panL.had) {
       chan[i].pan=chan[i].std.panL.val;
       chWrite(i,0x03,chan[i].pan);
diff --git a/src/engine/platform/su.h b/src/engine/platform/su.h
index 5baf13f0..6291d453 100644
--- a/src/engine/platform/su.h
+++ b/src/engine/platform/su.h
@@ -31,7 +31,8 @@ class DivPlatformSoundUnit: public DivDispatch {
     int ins, cutoff, res, control;
     signed char pan;
     unsigned char duty;
-    bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, noise, pcm;
+    bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, noise, pcm, phaseReset, filterPhaseReset;
+    bool pcmLoop, timerSync, freqSweep, volSweep, cutSweep;
     signed char vol, outVol, wave;
     DivMacroInt std;
     Channel():
@@ -53,9 +54,16 @@ class DivPlatformSoundUnit: public DivDispatch {
       inPorta(false),
       noise(false),
       pcm(false),
+      phaseReset(false),
+      filterPhaseReset(false),
+      pcmLoop(false),
+      timerSync(false),
+      freqSweep(false),
+      volSweep(false),
+      cutSweep(false),
       vol(127),
       outVol(127),
-      wave(-1) {}
+      wave(0) {}
   };
   Channel chan[8];
   bool isMuted[8];
@@ -74,6 +82,7 @@ class DivPlatformSoundUnit: public DivDispatch {
   SoundUnit* su;
   unsigned char regPool[128];
   void writeControl(int ch);
+  void writeControlUpper(int ch);
 
   friend void putDispatchChan(void*,int,int);
   public:
diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index 7039f164..8631e74f 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -2890,7 +2890,8 @@ void FurnaceGUI::drawInsEdit() {
                 ins->type==DIV_INS_OPLL ||
                 ins->type==DIV_INS_AY ||
                 ins->type==DIV_INS_AY8930 ||
-                ins->type==DIV_INS_SWAN) {
+                ins->type==DIV_INS_SWAN ||
+                ins->type==DIV_INS_SU) {
               NORMAL_MACRO(ins->std.phaseResetMacro,0,1,"phaseReset","Phase Reset",32,ins->std.phaseResetMacro.open,true,NULL,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[16],0,1,NULL,false);
             }
             if (ex1Max>0) {