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YM2610(B): use f-num/block baseFreq calculation

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also allow for different octave boundary f-nums depending on chip clock
This commit is contained in:
tildearrow 2022-05-10 02:22:08 -05:00
parent da71a6a804
commit 5e14177e4e
12 changed files with 198 additions and 170 deletions
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56
src/engine/platform/ym2610bext.cpp
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@ -120,31 +120,51 @@ int DivPlatformYM2610BExt::dispatch(DivCommand c) {
break;
}
case DIV_CMD_NOTE_PORTA: {
int destFreq=NOTE_FREQUENCY(c.value2);
int boundaryBottom=parent->calcBaseFreq(chipClock,CHIP_FREQBASE,0,false);
int boundaryTop=parent->calcBaseFreq(chipClock,CHIP_FREQBASE,12,false);
int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
int newFreq;
bool return2=false;
if (opChan[ch].portaPause) {
opChan[ch].baseFreq=opChan[ch].portaPauseFreq;
}
if (destFreq>opChan[ch].baseFreq) {
newFreq=opChan[ch].baseFreq+c.value*octave(opChan[ch].baseFreq);
newFreq=opChan[ch].baseFreq+c.value;
if (newFreq>=destFreq) {
newFreq=destFreq;
return2=true;
}
} else {
newFreq=opChan[ch].baseFreq-c.value*octave(opChan[ch].baseFreq);
newFreq=opChan[ch].baseFreq-c.value;
if (newFreq<=destFreq) {
newFreq=destFreq;
return2=true;
}
}
// what the heck!
if (!opChan[ch].portaPause) {
if (octave(opChan[ch].baseFreq)!=octave(newFreq)) {
opChan[ch].portaPause=true;
break;
if ((newFreq&0x7ff)>boundaryTop && (newFreq&0xf800)<0x3800) {
if (parent->song.fbPortaPause) {
opChan[ch].portaPauseFreq=(boundaryBottom)|((newFreq+0x800)&0xf800);
opChan[ch].portaPause=true;
break;
} else {
newFreq=(newFreq>>1)|((newFreq+0x800)&0xf800);
}
}
if ((newFreq&0x7ff)<boundaryBottom && (newFreq&0xf800)>0) {
if (parent->song.fbPortaPause) {
opChan[ch].portaPauseFreq=newFreq=(boundaryTop-1)|((newFreq-0x800)&0xf800);
opChan[ch].portaPause=true;
break;
} else {
newFreq=(newFreq<<1)|((newFreq-0x800)&0xf800);
}
}
}
opChan[ch].baseFreq=newFreq;
opChan[ch].portaPause=false;
opChan[ch].freqChanged=true;
opChan[ch].baseFreq=newFreq;
if (return2) return 2;
break;
}
@ -364,14 +384,20 @@ void DivPlatformYM2610BExt::tick(bool sysTick) {
unsigned char writeMask=2;
if (extMode) for (int i=0; i<4; i++) {
if (opChan[i].freqChanged) {
opChan[i].freq=parent->calcFreq(opChan[i].baseFreq,opChan[i].pitch,false,octave(opChan[i].baseFreq),opChan[i].pitch2);
if (opChan[i].freq>262143) opChan[i].freq=262143;
int freqt=toFreq(opChan[i].freq);
opChan[i].freqH=freqt>>8;
opChan[i].freqL=freqt&0xff;
immWrite(opChanOffsH[i],opChan[i].freqH);
immWrite(opChanOffsL[i],opChan[i].freqL);
opChan[i].freqChanged=false;
int fNum=parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch,false,4,opChan[i].pitch2);
int block=(opChan[i].baseFreq&0xf800)>>11;
if (fNum<0) fNum=0;
if (fNum>2047) {
while (block<7) {
fNum>>=1;
block++;
}
if (fNum>2047) fNum=2047;
}
opChan[i].freq=(block<<11)|fNum;
if (opChan[i].freq>0x3fff) opChan[i].freq=0x3fff;
immWrite(opChanOffsH[i],opChan[i].freq>>8);
immWrite(opChanOffsL[i],opChan[i].freq&0xff);
}
writeMask|=opChan[i].active<<(4+i);
if (opChan[i].keyOn) {