a lot of work

- round to nearest instead of round to zero in SMS period calc
- implement arpeggio
- implement arp macro (kinda)
- polish the SMS platform
- correct the DIV_CMD_PITCH range to 1 semitone
- fix PSG volume in Genesis
- use a better register write strat in Genesis
- fix a bug caused by legacy code
- implement ECxx command
- implement EDxx command
- implement SN noise mode command
- vibrato table is now 64 positions long (instead of 60)

src/engine/dispatch.h

@@ -1,6 +1,8 @@
 #ifndef _DISPATCH_H
 #define _DISPATCH_H
 
+#define ONE_SEMITONE 2200
+
 enum DivDispatchCmds {
   DIV_CMD_NOTE_ON=0,
   DIV_CMD_NOTE_OFF,
@@ -64,7 +66,7 @@ class DivDispatch {
      * the engine shall resample to the output rate.
      */
     int rate;
-    virtual void acquire(short& l, short& r);
+    virtual void acquire(int& l, int& r);
     virtual int dispatch(DivCommand c);
     virtual void tick();
 

src/engine/engine.cpp

@@ -668,8 +668,8 @@ bool DivEngine::init() {
   bbOut[0]=new short[got.bufsize];
   bbOut[1]=new short[got.bufsize];
 
-  for (int i=0; i<60; i++) {
+  for (int i=0; i<64; i++) {
-    vibTable[i]=127*sin(((double)i/60.0)*(2*M_PI));
+    vibTable[i]=127*sin(((double)i/64.0)*(2*M_PI));
   }
 
   switch (song.system) {

src/engine/engine.h

@@ -8,9 +8,10 @@
 struct DivChannelState {
   std::vector<DivDelayedCommand> delayed;
   int note, pitch, portaSpeed, portaNote;
-  int volume, volSpeed;
+  int volume, volSpeed, cut, rowDelay;
   int vibratoDepth, vibratoRate, vibratoPos;
   int tremoloDepth, tremoloRate, tremoloPos;
+  unsigned char arp, arpStage;
   bool doNote, legato;
 
   DivChannelState():
@@ -20,12 +21,16 @@ struct DivChannelState {
     portaNote(-1),
     volume(0x7f00),
     volSpeed(0),
+    cut(-1),
+    rowDelay(0),
     vibratoDepth(0),
     vibratoRate(0),
     vibratoPos(0),
     tremoloDepth(0),
     tremoloRate(0),
     tremoloPos(0),
+    arp(0),
+    arpStage(-1),
     doNote(false), legato(false) {}
 };
 
@@ -40,12 +45,13 @@ class DivEngine {
   int changeOrd, changePos;
   DivChannelState chan[17];
 
-  short vibTable[60];
+  short vibTable[64];
 
   blip_buffer_t* bb[2];
-  short temp[2], prevSample[2];
+  int temp[2], prevSample[2];
   short* bbOut[2];
 
+  void processRow(int i, bool afterDelay);
   void nextOrder();
   void nextRow();
   void nextTick();

src/engine/platform/abstract.cpp

@@ -1,6 +1,6 @@
 #include "../dispatch.h"
 
-void DivDispatch::acquire(short& l, short& r) {
+void DivDispatch::acquire(int& l, int& r) {
   l=0;
   r=0;
 }

src/engine/platform/dummy.cpp

@@ -1,7 +1,7 @@
 #include "dummy.h"
 #include <math.h>
 
-void DivPlatformDummy::acquire(short& l, short& r) {
+void DivPlatformDummy::acquire(int& l, int& r) {
   l=0;
   for (unsigned char i=0; i<chans; i++) {
     if (chan[i].active) {

src/engine/platform/dummy.h

@@ -13,7 +13,7 @@ class DivPlatformDummy: public DivDispatch {
   Channel chan[17];
   unsigned char chans;
   public:
-    void acquire(short& l, short& r);
+    void acquire(int& l, int& r);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);

src/engine/platform/genesis.cpp

@@ -5,7 +5,7 @@
 
 // TODO fix all the writes.
 // i think there is no wait for data writes, just for ON/OFF writes
-void DivPlatformGenesis::acquire(short& l, short& r) {
+void DivPlatformGenesis::acquire(int& l, int& r) {
   static short o[2];
 
   if (dacMode && dacSample!=-1) {
@@ -43,7 +43,7 @@ void DivPlatformGenesis::acquire(short& l, short& r) {
   if (psgClocks>=rate) {
     psg.acquire(psgOut,psgOut);
     psgClocks-=rate;
-    psgOut>>=2;
+    psgOut=(psgOut>>2)+(psgOut>>3);
   }
 
   l=(o[0]<<7)+psgOut;
@@ -89,9 +89,9 @@ void DivPlatformGenesis::tick() {
   }
 
   for (int i=0; i<512; i++) {
-    if (pendingWrites[i]!=-1) {
+    if (pendingWrites[i]!=oldWrites[i]) {
       writes.emplace(i,pendingWrites[i]&0xff);
-      pendingWrites[i]=-1;
+      oldWrites[i]=pendingWrites[i];
     }
   }
 
@@ -156,28 +156,25 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       }
       DivInstrument* ins=parent->song.ins[chan[c.chan].ins];
       
-      if (chan[c.chan].insChanged) {
+      for (int i=0; i<4; i++) {
-        chan[c.chan].insChanged=false;
+        unsigned short baseAddr=chanOffs[c.chan]|opOffs[i];
-        for (int i=0; i<4; i++) {
+        DivInstrumentFM::Operator op=ins->fm.op[i];
-          unsigned short baseAddr=chanOffs[c.chan]|opOffs[i];
+        rWrite(baseAddr+0x30,(op.mult&15)|(dtTable[op.dt&7]<<4));
-          DivInstrumentFM::Operator op=ins->fm.op[i];
+        if (isOutput[ins->fm.alg][i]) {
-          rWrite(baseAddr+0x30,(op.mult&15)|(dtTable[op.dt&7]<<4));
+          rWrite(baseAddr+0x40,127-(((127-op.tl)*chan[c.chan].vol)/127));
-          if (isOutput[ins->fm.alg][i]) {
+        } else {
-            rWrite(baseAddr+0x40,127-(((127-op.tl)*chan[c.chan].vol)/127));
+          rWrite(baseAddr+0x40,op.tl);
-          } else {
-            rWrite(baseAddr+0x40,op.tl);
-          }
-          rWrite(baseAddr+0x50,(op.ar&31)|(op.rs<<6));
-          rWrite(baseAddr+0x60,(op.dr&31)|(op.am<<7));
-          rWrite(baseAddr+0x70,op.d2r&31);
-          rWrite(baseAddr+0x80,(op.rr&15)|(op.sl<<4));
-          rWrite(baseAddr+0x90,op.ssgEnv&15);
         }
-        rWrite(chanOffs[c.chan]+0xb0,(ins->fm.alg&7)|(ins->fm.fb<<3));
+        rWrite(baseAddr+0x50,(op.ar&31)|(op.rs<<6));
-        rWrite(chanOffs[c.chan]+0xb4,(chan[c.chan].pan<<6)|(ins->fm.fms&7)|((ins->fm.ams&3)<<4));
+        rWrite(baseAddr+0x60,(op.dr&31)|(op.am<<7));
+        rWrite(baseAddr+0x70,op.d2r&31);
+        rWrite(baseAddr+0x80,(op.rr&15)|(op.sl<<4));
+        rWrite(baseAddr+0x90,op.ssgEnv&15);
       }
+      rWrite(chanOffs[c.chan]+0xb0,(ins->fm.alg&7)|(ins->fm.fb<<3));
+      rWrite(chanOffs[c.chan]+0xb4,(chan[c.chan].pan<<6)|(ins->fm.fms&7)|((ins->fm.ams&3)<<4));
       chan[c.chan].baseFreq=644.0f*pow(2.0f,((float)c.value/12.0f));
-      chan[c.chan].freq=(chan[c.chan].baseFreq*(2048+chan[c.chan].pitch))>>11;
+      chan[c.chan].freq=(chan[c.chan].baseFreq*(ONE_SEMITONE+chan[c.chan].pitch))/ONE_SEMITONE;
       chan[c.chan].freqChanged=true;
       chan[c.chan].keyOn=true;
       chan[c.chan].active=true;
@@ -225,7 +222,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
     }
     case DIV_CMD_PITCH: {
       chan[c.chan].pitch=c.value;
-      chan[c.chan].freq=(chan[c.chan].baseFreq*(2048+chan[c.chan].pitch))>>11;
+      chan[c.chan].freq=(chan[c.chan].baseFreq*(ONE_SEMITONE+chan[c.chan].pitch))/ONE_SEMITONE;
       chan[c.chan].freqChanged=true;
       break;
     }
@@ -245,7 +242,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
           return2=true;
         }
       }
-      chan[c.chan].freq=(chan[c.chan].baseFreq*(2048+chan[c.chan].pitch))>>11;
+      chan[c.chan].freq=(chan[c.chan].baseFreq*(ONE_SEMITONE+chan[c.chan].pitch))/ONE_SEMITONE;
       chan[c.chan].freqChanged=true;
       if (return2) return 2;
       break;
@@ -259,7 +256,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
     }
     case DIV_CMD_LEGATO: {
       chan[c.chan].baseFreq=644.0f*pow(2.0f,((float)c.value/12.0f));
-      chan[c.chan].freq=(chan[c.chan].baseFreq*(2048+chan[c.chan].pitch))>>11;
+      chan[c.chan].freq=(chan[c.chan].baseFreq*(ONE_SEMITONE+chan[c.chan].pitch))/ONE_SEMITONE;
       chan[c.chan].freqChanged=true;
       break;
     }
@@ -312,6 +309,7 @@ int DivPlatformGenesis::init(DivEngine* p, int channels, int sugRate) {
   }
 
   for (int i=0; i<512; i++) {
+    oldWrites[i]=-1;
     pendingWrites[i]=-1;
   }
 

src/engine/platform/genesis.h

@@ -26,7 +26,7 @@ class DivPlatformGenesis: public DivDispatch {
   ym3438_t fm;
   DivPlatformSMS psg;
   int psgClocks;
-  short psgOut;
+  int psgOut;
   int delay;
   unsigned char lastBusy;
 
@@ -36,10 +36,11 @@ class DivPlatformGenesis: public DivDispatch {
   int dacPos;
   int dacSample;
 
+  short oldWrites[512];
   short pendingWrites[512];
 
   public:
-    void acquire(short& l, short& r);
+    void acquire(int& l, int& r);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);

src/engine/platform/sms.cpp

@@ -2,7 +2,7 @@
 #include "../engine.h"
 #include <math.h>
 
-void DivPlatformSMS::acquire(short& l, short& r) {
+void DivPlatformSMS::acquire(int& l, int& r) {
   short v;
   sn->sound_stream_update(&v,1);
   l=v;
@@ -13,10 +13,14 @@ void DivPlatformSMS::tick() {
   for (int i=0; i<4; i++) {
     chan[i].std.next();
     if (chan[i].std.hadVol) sn->write(0x90|(i<<5)|(15-((chan[i].vol*chan[i].std.vol)>>4)));
+    if (chan[i].std.hadArp) {
+      chan[i].baseFreq=round(1712.0f/pow(2.0f,((float)(chan[i].note+chan[i].std.arp-12)/12.0f)));
+      chan[i].freqChanged=true;
+    }
   }
   for (int i=0; i<3; i++) {
     if (chan[i].freqChanged) {
-      chan[i].freq=(chan[i].baseFreq*(2048-chan[i].pitch))>>11;
+      chan[i].freq=(chan[i].baseFreq*(ONE_SEMITONE-chan[i].pitch))/ONE_SEMITONE;
       sn->write(0x80|i<<5|(chan[i].freq&15));
       sn->write(chan[i].freq>>4);
       chan[i].freqChanged=false;
@@ -24,7 +28,7 @@ void DivPlatformSMS::tick() {
   }
   if (chan[3].freqChanged || updateSNMode) {
     updateSNMode=false;
-    chan[3].freq=(chan[3].baseFreq*(2048-chan[3].pitch))>>11;
+    chan[3].freq=(chan[3].baseFreq*(ONE_SEMITONE-chan[3].pitch))/ONE_SEMITONE;
     chan[3].freqChanged=false;
     if (snNoiseMode&2) { // take period from channel 3
       if (snNoiseMode&1) {
@@ -47,7 +51,7 @@ void DivPlatformSMS::tick() {
 int DivPlatformSMS::dispatch(DivCommand c) {
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON:
-      chan[c.chan].baseFreq=1712/pow(2.0f,((float)c.value/12.0f));
+      chan[c.chan].baseFreq=round(1712.0f/pow(2.0f,((float)c.value/12.0f)));
       chan[c.chan].freqChanged=true;
       chan[c.chan].note=c.value;
       chan[c.chan].active=true;
@@ -61,7 +65,7 @@ int DivPlatformSMS::dispatch(DivCommand c) {
       break;
     case DIV_CMD_INSTRUMENT:
       chan[c.chan].ins=c.value;
-      chan[c.chan].std.init(parent->song.ins[chan[c.chan].ins]);
+      //chan[c.chan].std.init(parent->song.ins[chan[c.chan].ins]);
       break;
     case DIV_CMD_VOLUME:
       chan[c.chan].vol=c.value;
@@ -71,10 +75,35 @@ int DivPlatformSMS::dispatch(DivCommand c) {
       chan[c.chan].pitch=c.value;
       chan[c.chan].freqChanged=true;
       break;
+    case DIV_CMD_NOTE_PORTA: {
+      int destFreq=round(1712.0f/pow(2.0f,((float)c.value2/12.0f)));
+      bool return2=false;
+      if (destFreq>chan[c.chan].baseFreq) {
+        chan[c.chan].baseFreq+=c.value;
+        if (chan[c.chan].baseFreq>=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      } else {
+        chan[c.chan].baseFreq-=c.value;
+        if (chan[c.chan].baseFreq<=destFreq) {
+          chan[c.chan].baseFreq=destFreq;
+          return2=true;
+        }
+      }
+      chan[c.chan].freqChanged=true;
+      if (return2) return 2;
+      break;
+    }
     case DIV_CMD_STD_NOISE_MODE:
       snNoiseMode=(c.value&1)|((c.value&16)>>3);
       updateSNMode=true;
       break;
+    case DIV_CMD_LEGATO:
+      chan[c.chan].baseFreq=round(1712.0f/pow(2.0f,((float)c.value/12.0f)));
+      chan[c.chan].freqChanged=true;
+      chan[c.chan].note=c.value;
+      break;
     default:
       break;
   }

src/engine/platform/sms.h

@@ -19,7 +19,7 @@ class DivPlatformSMS: public DivDispatch {
   bool updateSNMode;
   sn76496_device* sn;
   public:
-    void acquire(short& l, short& r);
+    void acquire(int& l, int& r);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);

src/engine/playback.cpp

@@ -29,6 +29,9 @@ bool DivEngine::perSystemEffect(int ch, unsigned char effect, unsigned char effe
         case 0x17: // DAC enable
           dispatch->dispatch(DivCommand(DIV_CMD_SAMPLE_MODE,ch,(effectVal>0)));
           break;
+        case 0x20: // SN noise mode
+          dispatch->dispatch(DivCommand(DIV_CMD_STD_NOISE_MODE,ch,effectVal));
+          break;
         default:
           return false;
       }
@@ -100,6 +103,155 @@ bool DivEngine::perSystemPostEffect(int ch, unsigned char effect, unsigned char
   return true;
 }
 
+void DivEngine::processRow(int i, bool afterDelay) {
+  DivPattern* pat=song.pat[i]->data[curOrder];
+  // pre effects
+  if (!afterDelay) for (int j=0; j<song.pat[i]->effectRows; j++) {
+    short effect=pat->data[curRow][4+(j<<1)];
+    short effectVal=pat->data[curRow][5+(j<<1)];
+
+    if (effectVal==-1) effectVal=0;
+    if (effect==0xed) {
+      chan[i].rowDelay=effectVal+1;
+      return;
+    }
+  }
+
+  // instrument
+  if (pat->data[curRow][2]!=-1) {
+    dispatch->dispatch(DivCommand(DIV_CMD_INSTRUMENT,i,pat->data[curRow][2]));
+  }
+  // note
+  if (pat->data[curRow][0]==100) {
+    chan[i].note=-1;
+    dispatch->dispatch(DivCommand(DIV_CMD_NOTE_OFF,i));
+  } else if (!(pat->data[curRow][0]==0 && pat->data[curRow][1]==0)) {
+    chan[i].note=pat->data[curRow][0]+pat->data[curRow][1]*12;
+    chan[i].doNote=true;
+  }
+
+  // volume
+  if (pat->data[curRow][3]!=-1) {
+    chan[i].volume=pat->data[curRow][3]<<8;
+    dispatch->dispatch(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
+  }
+
+  // effects
+  for (int j=0; j<song.pat[i]->effectRows; j++) {
+    short effect=pat->data[curRow][4+(j<<1)];
+    short effectVal=pat->data[curRow][5+(j<<1)];
+
+    if (effectVal==-1) effectVal=0;
+
+    // per-system effect
+    if (!perSystemEffect(i,effect,effectVal)) switch (effect) {
+      case 0x09: // speed 1
+        song.speed1=effectVal;
+        break;
+      case 0x0f: // speed 2
+        song.speed2=effectVal;
+        break;
+      case 0x0b: // change order
+        changeOrd=effectVal;
+        changePos=0;
+        break;
+      case 0x0d: // next order
+        changeOrd=curOrder+1;
+        changePos=effectVal;
+        break;
+      case 0x08: // panning
+        dispatch->dispatch(DivCommand(DIV_CMD_PANNING,i,effectVal));
+        break;
+      case 0x01: // ramp up
+        if (effectVal==0) {
+          chan[i].portaNote=-1;
+          chan[i].portaSpeed=-1;
+        } else {
+          chan[i].portaNote=0x60;
+          chan[i].portaSpeed=effectVal;
+        }
+        break;
+      case 0x02: // ramp down
+        if (effectVal==0) {
+          chan[i].portaNote=-1;
+          chan[i].portaSpeed=-1;
+        } else {
+          chan[i].portaNote=0x00;
+          chan[i].portaSpeed=effectVal;
+        }
+        break;
+      case 0x03: // portamento
+        if (effectVal==0) {
+          chan[i].portaNote=-1;
+          chan[i].portaSpeed=-1;
+        } else {
+          chan[i].portaNote=chan[i].note;
+          chan[i].portaSpeed=effectVal;
+          chan[i].doNote=false;
+        }
+        break;
+      case 0x04: // vibrato
+        chan[i].vibratoDepth=effectVal&15;
+        chan[i].vibratoRate=effectVal>>4;
+        dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>4)));
+        break;
+      case 0x0a: // volume ramp
+        if (effectVal!=0) {
+          if ((effectVal&15)!=0) {
+            chan[i].volSpeed=-(effectVal&15)*64;
+          } else {
+            chan[i].volSpeed=(effectVal>>4)*64;
+          }
+        } else {
+          chan[i].volSpeed=0;
+        }
+        break;
+      case 0x00: // arpeggio
+        chan[i].arp=effectVal;
+        break;
+      
+      case 0xe1: // portamento up
+        chan[i].portaNote=chan[i].note+(effectVal&15);
+        chan[i].portaSpeed=(effectVal>>4)*3;
+        break;
+      case 0xe2: // portamento down
+        chan[i].portaNote=chan[i].note-(effectVal&15);
+        chan[i].portaSpeed=(effectVal>>4)*3;
+        break;
+      case 0xe5: // pitch
+        chan[i].pitch=effectVal-0x80;
+        dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>2)));
+        break;
+      case 0xea: // legato mode
+        chan[i].legato=effectVal;
+        break;
+      case 0xec: // delayed note cut
+        chan[i].cut=effectVal;
+        break;
+    }
+  }
+
+  if (chan[i].doNote) {
+    chan[i].vibratoPos=0;
+    dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>4)));
+    if (chan[i].legato) {
+      dispatch->dispatch(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
+    } else {
+      dispatch->dispatch(DivCommand(DIV_CMD_NOTE_ON,i,chan[i].note));
+    }
+    chan[i].doNote=false;
+  }
+
+  // post effects
+  for (int j=0; j<song.pat[i]->effectRows; j++) {
+    short effect=pat->data[curRow][4+(j<<1)];
+    short effectVal=pat->data[curRow][5+(j<<1)];
+
+    if (effectVal==-1) effectVal=0;
+    perSystemPostEffect(i,effect,effectVal);
+  }
+}
+
 void DivEngine::nextRow() {
   static char pb[4096];
   static char pb1[4096];
@@ -156,135 +308,7 @@ void DivEngine::nextRow() {
   printf("| %.2x:%s | \x1b[1;33m%3d%s\x1b[m\n",curOrder,pb1,curRow,pb3);
 
   for (int i=0; i<chans; i++) {
-    DivPattern* pat=song.pat[i]->data[curOrder];
+    processRow(i,false);
-
-    // instrument
-    if (pat->data[curRow][2]!=-1) {
-      dispatch->dispatch(DivCommand(DIV_CMD_INSTRUMENT,i,pat->data[curRow][2]));
-    }
-    // note
-    if (pat->data[curRow][0]==100) {
-      chan[i].note=-1;
-      dispatch->dispatch(DivCommand(DIV_CMD_NOTE_OFF,i));
-    } else if (!(pat->data[curRow][0]==0 && pat->data[curRow][1]==0)) {
-      chan[i].note=pat->data[curRow][0]+pat->data[curRow][1]*12;
-      chan[i].doNote=true;
-    }
-
-    // volume
-    if (pat->data[curRow][3]!=-1) {
-      chan[i].volume=pat->data[curRow][3]<<8;
-      dispatch->dispatch(DivCommand(DIV_CMD_VOLUME,i,chan[i].volume>>8));
-    }
-
-    // effects
-    for (int j=0; j<song.pat[i]->effectRows; j++) {
-      short effect=pat->data[curRow][4+(j<<1)];
-      short effectVal=pat->data[curRow][5+(j<<1)];
-
-      if (effectVal==-1) effectVal=0;
-
-      // per-system effect
-      if (!perSystemEffect(i,effect,effectVal)) switch (effect) {
-        case 0x09: // speed 1
-          song.speed1=effectVal;
-          break;
-        case 0x0f: // speed 2
-          song.speed2=effectVal;
-          break;
-        case 0x0b: // change order
-          changeOrd=effectVal;
-          changePos=0;
-          break;
-        case 0x0d: // next order
-          changeOrd=curOrder+1;
-          changePos=effectVal;
-          break;
-        case 0x08: // panning
-          dispatch->dispatch(DivCommand(DIV_CMD_PANNING,i,effectVal));
-          break;
-        case 0x01: // ramp up
-          if (effectVal==0) {
-            chan[i].portaNote=-1;
-            chan[i].portaSpeed=-1;
-          } else {
-            chan[i].portaNote=0x60;
-            chan[i].portaSpeed=effectVal;
-          }
-          break;
-        case 0x02: // ramp down
-          if (effectVal==0) {
-            chan[i].portaNote=-1;
-            chan[i].portaSpeed=-1;
-          } else {
-            chan[i].portaNote=0x00;
-            chan[i].portaSpeed=effectVal;
-          }
-          break;
-        case 0x03: // portamento
-          if (effectVal==0) {
-            chan[i].portaNote=-1;
-            chan[i].portaSpeed=-1;
-          } else {
-            chan[i].portaNote=chan[i].note;
-            chan[i].portaSpeed=effectVal;
-            chan[i].doNote=false;
-          }
-          break;
-        case 0x04: // vibrato
-          chan[i].vibratoDepth=effectVal&15;
-          chan[i].vibratoRate=effectVal>>4;
-          dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>4)));
-          break;
-        case 0x0a: // volume ramp
-          if (effectVal!=0) {
-            if ((effectVal&15)!=0) {
-              chan[i].volSpeed=-(effectVal&15)*64;
-            } else {
-              chan[i].volSpeed=(effectVal>>4)*64;
-            }
-          } else {
-            chan[i].volSpeed=0;
-          }
-          break;
-        
-        case 0xe1: // portamento up
-          chan[i].portaNote=chan[i].note+(effectVal&15);
-          chan[i].portaSpeed=(effectVal>>4)*3;
-          break;
-        case 0xe2: // portamento down
-          chan[i].portaNote=chan[i].note-(effectVal&15);
-          chan[i].portaSpeed=(effectVal>>4)*3;
-          break;
-        case 0xe5: // pitch
-          chan[i].pitch=effectVal-0x80;
-          dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>2)));
-          break;
-        case 0xea: // legato mode
-          chan[i].legato=effectVal;
-          break;
-      }
-    }
-
-    if (chan[i].doNote) {
-      chan[i].vibratoPos=0;
-      dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>4)));
-      if (chan[i].legato) {
-        dispatch->dispatch(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
-      } else {
-        dispatch->dispatch(DivCommand(DIV_CMD_NOTE_ON,i,chan[i].note));
-      }
-      chan[i].doNote=false;
-    }
-
-    // post effects
-    for (int j=0; j<song.pat[i]->effectRows; j++) {
-      short effect=pat->data[curRow][4+(j<<1)];
-      short effectVal=pat->data[curRow][5+(j<<1)];
-
-      if (effectVal==-1) effectVal=0;
-      perSystemPostEffect(i,effect,effectVal);
-    }
   }
 }
 
@@ -309,6 +333,11 @@ void DivEngine::nextTick() {
   }
   // process stuff
   for (int i=0; i<chans; i++) {
+    if (chan[i].rowDelay>0) {
+      if (--chan[i].rowDelay==0) {
+        processRow(i,true);
+      }
+    }
     if (chan[i].volSpeed!=0) {
       chan[i].volume+=chan[i].volSpeed;
       if (chan[i].volume>0x7f00) chan[i].volume=0x7f00;
@@ -317,7 +346,7 @@ void DivEngine::nextTick() {
     }
     if (chan[i].vibratoDepth>0) {
       chan[i].vibratoPos+=chan[i].vibratoRate;
-      if (chan[i].vibratoPos>=60) chan[i].vibratoPos-=60;
+      if (chan[i].vibratoPos>=64) chan[i].vibratoPos-=64;
       dispatch->dispatch(DivCommand(DIV_CMD_PITCH,i,chan[i].pitch+((chan[i].vibratoDepth*vibTable[chan[i].vibratoPos])>>4)));
     }
     if (chan[i].portaSpeed>0) {
@@ -325,6 +354,27 @@ void DivEngine::nextTick() {
         chan[i].portaSpeed=0;
       }
     }
+    if (chan[i].cut>0) {
+      if (--chan[i].cut<1) {
+        chan[i].note=-1;
+        dispatch->dispatch(DivCommand(DIV_CMD_NOTE_OFF,i));
+      }
+    }
+    if (chan[i].arp!=0) {
+      chan[i].arpStage++;
+      if (chan[i].arpStage>2) chan[i].arpStage=0;
+      switch (chan[i].arpStage) {
+        case 0:
+          dispatch->dispatch(DivCommand(DIV_CMD_LEGATO,i,chan[i].note));
+          break;
+        case 1:
+          dispatch->dispatch(DivCommand(DIV_CMD_LEGATO,i,chan[i].note+(chan[i].arp>>4)));
+          break;
+        case 2:
+          dispatch->dispatch(DivCommand(DIV_CMD_LEGATO,i,chan[i].note+(chan[i].arp&15)));
+          break;
+      }
+    }
   }
 
   // system tick

src/main.cpp

@@ -27,6 +27,11 @@ int main(int argc, char** argv) {
     return 1;
   }
   ssize_t len=ftell(f);
+  if (len==0x7fffffffffffffff) {
+    perror("could not get file length");
+    fclose(f);
+    return 1;
+  }
   if (len<1) {
     if (len==0) {
       printf("that file is empty!\n");