Rewrite gus emulation a bit to make things a bit clearer
Remove the automatic amplification Slight rounding offset in the panning tables to match original gus tables Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@4001
This commit is contained in:
Sjoerd van der Berg
parent
7cd00b3d84
commit
22fff83790
1 changed files with 126 additions and 101 deletions
|
|
@ -32,10 +32,9 @@
|
|||
using namespace std;
|
||||
|
||||
//Extra bits of precision over normal gus
|
||||
#define WAVE_BITS 2
|
||||
#define WAVE_FRACT (9+WAVE_BITS)
|
||||
#define WAVE_FRACT 9
|
||||
#define WAVE_FRACT_MASK ((1 << WAVE_FRACT)-1)
|
||||
#define WAVE_MSWMASK ((1 << (16+WAVE_BITS))-1)
|
||||
#define WAVE_MSWMASK ((1 << 16)-1)
|
||||
#define WAVE_LSWMASK (0xffffffff ^ WAVE_MSWMASK)
|
||||
|
||||
//Amount of precision the volume has
|
||||
|
|
@ -44,14 +43,24 @@ using namespace std;
|
|||
|
||||
#define GUS_BASE myGUS.portbase
|
||||
#define GUS_RATE myGUS.rate
|
||||
#define LOG_GUS 0
|
||||
#define LOG_GUS 1
|
||||
|
||||
#define VOL_SHIFT 14
|
||||
|
||||
#define WCTRL_STOPPED 0x01
|
||||
#define WCTRL_STOP 0x02
|
||||
#define WCTRL_16BIT 0x04
|
||||
#define WCTRL_LOOP 0x08
|
||||
#define WCTRL_BIDIRECTIONAL 0x10
|
||||
#define WCTRL_IRQENABLED 0x20
|
||||
#define WCTRL_DECREASING 0x40
|
||||
#define WCTRL_IRQPENDING 0x80
|
||||
|
||||
Bit8u adlib_commandreg;
|
||||
static MixerChannel * gus_chan;
|
||||
static Bit8u irqtable[8] = { 0, 2, 5, 3, 7, 11, 12, 15 };
|
||||
static Bit8u dmatable[8] = { 0, 1, 3, 5, 6, 7, 0, 0 };
|
||||
static Bit8u GUSRam[1024*1024]; // 1024K of GUS Ram
|
||||
static Bit32s AutoAmp = 512;
|
||||
static Bit16u vol16bit[4096];
|
||||
static Bit32u pantable[16];
|
||||
|
||||
|
|
@ -102,41 +111,6 @@ Bitu DEBUG_EnableDebugger(void);
|
|||
|
||||
static void GUS_DMA_Callback(DmaChannel * chan,DMAEvent event);
|
||||
|
||||
// Returns a single 16-bit sample from the Gravis's RAM
|
||||
static INLINE Bit32s GetSample(Bit32u Delta, Bit32u CurAddr, bool eightbit) {
|
||||
Bit32u useAddr;
|
||||
Bit32u holdAddr;
|
||||
useAddr = CurAddr >> WAVE_FRACT;
|
||||
if (eightbit) {
|
||||
if (Delta >= (1 << WAVE_FRACT)) {
|
||||
Bit32s tmpsmall = (Bit8s)GUSRam[useAddr];
|
||||
return tmpsmall << 8;
|
||||
} else {
|
||||
// Interpolate
|
||||
Bit32s w1 = ((Bit8s)GUSRam[useAddr+0]) << 8;
|
||||
Bit32s w2 = ((Bit8s)GUSRam[useAddr+1]) << 8;
|
||||
Bit32s diff = w2 - w1;
|
||||
return (w1+((diff*(Bit32s)(CurAddr&WAVE_FRACT_MASK ))>>WAVE_FRACT));
|
||||
}
|
||||
} else {
|
||||
// Formula used to convert addresses for use with 16-bit samples
|
||||
holdAddr = useAddr & 0xc0000L;
|
||||
useAddr = useAddr & 0x1ffffL;
|
||||
useAddr = useAddr << 1;
|
||||
useAddr = (holdAddr | useAddr);
|
||||
|
||||
if(Delta >= (1 << WAVE_FRACT)) {
|
||||
return (GUSRam[useAddr+0] | (((Bit8s)GUSRam[useAddr+1]) << 8));
|
||||
} else {
|
||||
// Interpolate
|
||||
Bit32s w1 = (GUSRam[useAddr+0] | (((Bit8s)GUSRam[useAddr+1]) << 8));
|
||||
Bit32s w2 = (GUSRam[useAddr+2] | (((Bit8s)GUSRam[useAddr+3]) << 8));
|
||||
Bit32s diff = w2 - w1;
|
||||
return (w1+((diff*(Bit32s)(CurAddr&WAVE_FRACT_MASK ))>>WAVE_FRACT));
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
class GUSChannels {
|
||||
public:
|
||||
Bit32u WaveStart;
|
||||
|
|
@ -183,7 +157,46 @@ public:
|
|||
PanLeft = 0;
|
||||
PanRight = 0;
|
||||
PanPot = 0x7;
|
||||
};
|
||||
}
|
||||
|
||||
// Returns a single 16-bit sample from the Gravis's RAM
|
||||
|
||||
INLINE Bit32s GetSample8() const {
|
||||
Bit32u useAddr = WaveAddr >> WAVE_FRACT;
|
||||
if (WaveAdd >= (1 << WAVE_FRACT)) {
|
||||
Bit32s tmpsmall = (Bit8s)GUSRam[useAddr];
|
||||
return tmpsmall << 8;
|
||||
}
|
||||
else {
|
||||
Bit32u nextAddr = (useAddr + 1) & ( 1024 * 1024 - 1 );
|
||||
// Interpolate
|
||||
Bit32s w1 = ((Bit8s)GUSRam[useAddr]) << 8;
|
||||
Bit32s w2 = ((Bit8s)GUSRam[nextAddr]) << 8;
|
||||
Bit32s diff = w2 - w1;
|
||||
Bit32s scale = (Bit32s)(WaveAddr&WAVE_FRACT_MASK);
|
||||
return (w1 + ((diff*scale) >> WAVE_FRACT));
|
||||
}
|
||||
}
|
||||
|
||||
INLINE Bit32s GetSample16() const {
|
||||
// Formula used to convert addresses for use with 16-bit samples
|
||||
Bit32u holdAddr = WaveAddr & 0xc0000L;
|
||||
Bit32u useAddr = WaveAddr & 0x1ffffL;
|
||||
useAddr = useAddr << 1;
|
||||
useAddr = (holdAddr | useAddr);
|
||||
if (WaveAdd >= (1 << WAVE_FRACT)) {
|
||||
return (GUSRam[useAddr + 0] | (((Bit8s)GUSRam[useAddr + 1]) << 8));
|
||||
}
|
||||
else {
|
||||
// Interpolate
|
||||
Bit32s w1 = (GUSRam[useAddr + 0] | (((Bit8s)GUSRam[useAddr + 1]) << 8));
|
||||
Bit32s w2 = (GUSRam[useAddr + 2] | (((Bit8s)GUSRam[useAddr + 3]) << 8));
|
||||
Bit32s diff = w2 - w1;
|
||||
Bit32s scale = (Bit32s)(WaveAddr&WAVE_FRACT_MASK);
|
||||
return (w1 + ((diff*scale) >> WAVE_FRACT));
|
||||
}
|
||||
}
|
||||
|
||||
void WriteWaveFreq(Bit16u val) {
|
||||
WaveFreq = val;
|
||||
double frameadd = double(val >> 1)/512.0; //Samples / original gus frame
|
||||
|
|
@ -219,13 +232,17 @@ public:
|
|||
void WriteRampCtrl(Bit8u val) {
|
||||
Bit32u old=myGUS.RampIRQ;
|
||||
RampCtrl = val & 0x7f;
|
||||
if ((val & 0xa0)==0xa0) myGUS.RampIRQ|=irqmask;
|
||||
else myGUS.RampIRQ&=~irqmask;
|
||||
if (old != myGUS.RampIRQ) CheckVoiceIrq();
|
||||
//Manually set the irq
|
||||
if ((val & 0xa0)==0xa0)
|
||||
myGUS.RampIRQ|=irqmask;
|
||||
else
|
||||
myGUS.RampIRQ&=~irqmask;
|
||||
if (old != myGUS.RampIRQ)
|
||||
CheckVoiceIrq();
|
||||
}
|
||||
INLINE Bit8u ReadRampCtrl(void) {
|
||||
Bit8u ret=RampCtrl;
|
||||
if (myGUS.RampIRQ & irqmask) ret|=0x80;
|
||||
if (myGUS.RampIRQ & irqmask) ret |= 0x80;
|
||||
return ret;
|
||||
}
|
||||
void WriteRampRate(Bit8u val) {
|
||||
|
|
@ -235,16 +252,18 @@ public:
|
|||
RampAdd = (Bit32u)realadd;
|
||||
}
|
||||
INLINE void WaveUpdate(void) {
|
||||
if (WaveCtrl & 0x3) return;
|
||||
if (WaveCtrl & ( WCTRL_STOP | WCTRL_STOPPED)) return;
|
||||
Bit32s WaveLeft;
|
||||
if (WaveCtrl & 0x40) {
|
||||
WaveAddr-=WaveAdd;
|
||||
WaveLeft=WaveStart-WaveAddr;
|
||||
if (WaveCtrl & WCTRL_DECREASING) {
|
||||
WaveAddr -= WaveAdd;
|
||||
WaveLeft = WaveStart-WaveAddr;
|
||||
} else {
|
||||
WaveAddr+=WaveAdd;
|
||||
WaveLeft=WaveAddr-WaveEnd;
|
||||
WaveAddr += WaveAdd;
|
||||
WaveLeft = WaveAddr-WaveEnd;
|
||||
}
|
||||
if (WaveLeft<0) return;
|
||||
//Not yet reaching a boundary
|
||||
if (WaveLeft<0)
|
||||
return;
|
||||
/* Generate an IRQ if needed */
|
||||
if (WaveCtrl & 0x20) {
|
||||
myGUS.WaveIRQ|=irqmask;
|
||||
|
|
@ -252,13 +271,13 @@ public:
|
|||
/* Check for not being in PCM operation */
|
||||
if (RampCtrl & 0x04) return;
|
||||
/* Check for looping */
|
||||
if (WaveCtrl & 0x08) {
|
||||
if (WaveCtrl & WCTRL_LOOP) {
|
||||
/* Bi-directional looping */
|
||||
if (WaveCtrl & 0x10) WaveCtrl^=0x40;
|
||||
WaveAddr = (WaveCtrl & 0x40) ? (WaveEnd-WaveLeft) : (WaveStart+WaveLeft);
|
||||
if (WaveCtrl & WCTRL_BIDIRECTIONAL) WaveCtrl^= WCTRL_DECREASING;
|
||||
WaveAddr = (WaveCtrl & WCTRL_DECREASING) ? (WaveEnd-WaveLeft) : (WaveStart+WaveLeft);
|
||||
} else {
|
||||
WaveCtrl|=1; //Stop the channel
|
||||
WaveAddr = (WaveCtrl & 0x40) ? WaveStart : WaveEnd;
|
||||
WaveAddr = (WaveCtrl & WCTRL_DECREASING) ? WaveStart : WaveEnd;
|
||||
}
|
||||
}
|
||||
INLINE void UpdateVolumes(void) {
|
||||
|
|
@ -299,21 +318,32 @@ public:
|
|||
}
|
||||
UpdateVolumes();
|
||||
}
|
||||
void generateSamples(Bit32s * stream,Bit32u len) {
|
||||
int i;
|
||||
Bit32s tmpsamp;
|
||||
bool eightbit;
|
||||
if (RampCtrl & WaveCtrl & 3) return;
|
||||
eightbit = ((WaveCtrl & 0x4) == 0);
|
||||
|
||||
for(i=0;i<(int)len;i++) {
|
||||
// Get sample
|
||||
tmpsamp = GetSample(WaveAdd, WaveAddr, eightbit);
|
||||
// Output stereo sample
|
||||
stream[i<<1]+= tmpsamp * VolLeft;
|
||||
stream[(i<<1)+1]+= tmpsamp * VolRight;
|
||||
WaveUpdate();
|
||||
RampUpdate();
|
||||
void generateSamples(Bit32s * stream,Bit32u len) {
|
||||
//Disabled channel
|
||||
if (RampCtrl & WaveCtrl & 3) return;
|
||||
|
||||
if (WaveCtrl & WCTRL_16BIT) {
|
||||
for (int i = 0; i < (int)len; i++) {
|
||||
// Get sample
|
||||
Bit32s tmpsamp = GetSample16();
|
||||
// Output stereo sample
|
||||
stream[i << 1] += tmpsamp * VolLeft;
|
||||
stream[(i << 1) + 1] += tmpsamp * VolRight;
|
||||
WaveUpdate();
|
||||
RampUpdate();
|
||||
}
|
||||
}
|
||||
else {
|
||||
for (int i = 0; i < (int)len; i++) {
|
||||
// Get sample
|
||||
Bit32s tmpsamp = GetSample8();
|
||||
// Output stereo sample
|
||||
stream[i << 1] += tmpsamp * VolLeft;
|
||||
stream[(i << 1) + 1] += tmpsamp * VolRight;
|
||||
WaveUpdate();
|
||||
RampUpdate();
|
||||
}
|
||||
}
|
||||
}
|
||||
};
|
||||
|
|
@ -401,20 +431,20 @@ static Bit16u ExecuteReadRegister(void) {
|
|||
else return 0x0300;
|
||||
|
||||
case 0x82: // Channel MSB start address register
|
||||
if (curchan) return (Bit16u)(curchan->WaveStart >> (WAVE_BITS+16));
|
||||
if (curchan) return (Bit16u)(curchan->WaveStart >> 16);
|
||||
else return 0x0000;
|
||||
case 0x83: // Channel LSW start address register
|
||||
if (curchan) return (Bit16u)(curchan->WaveStart >> WAVE_BITS);
|
||||
if (curchan) return (Bit16u)(curchan->WaveStart );
|
||||
else return 0x0000;
|
||||
|
||||
case 0x89: // Channel volume register
|
||||
if (curchan) return (Bit16u)((curchan->RampVol >> RAMP_FRACT) << 4);
|
||||
else return 0x0000;
|
||||
case 0x8a: // Channel MSB current address register
|
||||
if (curchan) return (Bit16u)(curchan->WaveAddr >> (WAVE_BITS+16));
|
||||
if (curchan) return (Bit16u)(curchan->WaveAddr >> 16);
|
||||
else return 0x0000;
|
||||
case 0x8b: // Channel LSW current address register
|
||||
if (curchan) return (Bit16u)(curchan->WaveAddr >> WAVE_BITS);
|
||||
if (curchan) return (Bit16u)(curchan->WaveAddr );
|
||||
else return 0x0000;
|
||||
|
||||
case 0x8d: // Channel volume control register
|
||||
|
|
@ -461,25 +491,25 @@ static void ExecuteGlobRegister(void) {
|
|||
break;
|
||||
case 0x2: // Channel MSW start address register
|
||||
if (curchan) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData & 0x1fff) << (16+WAVE_BITS);
|
||||
Bit32u tmpaddr = (Bit32u)((myGUS.gRegData & 0x1fff) << 16);
|
||||
curchan->WaveStart = (curchan->WaveStart & WAVE_MSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
case 0x3: // Channel LSW start address register
|
||||
if(curchan != NULL) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData) << WAVE_BITS;
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData);
|
||||
curchan->WaveStart = (curchan->WaveStart & WAVE_LSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
case 0x4: // Channel MSW end address register
|
||||
if(curchan != NULL) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData & 0x1fff) << (16+WAVE_BITS);
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData & 0x1fff) << 16;
|
||||
curchan->WaveEnd = (curchan->WaveEnd & WAVE_MSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
case 0x5: // Channel MSW end address register
|
||||
if(curchan != NULL) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData) << WAVE_BITS;
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData);
|
||||
curchan->WaveEnd = (curchan->WaveEnd & WAVE_LSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
|
|
@ -510,13 +540,13 @@ static void ExecuteGlobRegister(void) {
|
|||
break;
|
||||
case 0xA: // Channel MSW current address register
|
||||
if(curchan != NULL) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData & 0x1fff) << (16+WAVE_BITS);
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData & 0x1fff) << 16;
|
||||
curchan->WaveAddr = (curchan->WaveAddr & WAVE_MSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
case 0xB: // Channel LSW current address register
|
||||
if(curchan != NULL) {
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData) << (WAVE_BITS);
|
||||
Bit32u tmpaddr = (Bit32u)(myGUS.gRegData);
|
||||
curchan->WaveAddr = (curchan->WaveAddr & WAVE_LSWMASK) | tmpaddr;
|
||||
}
|
||||
break;
|
||||
|
|
@ -533,9 +563,9 @@ static void ExecuteGlobRegister(void) {
|
|||
if(myGUS.ActiveChannels > 32) myGUS.ActiveChannels = 32;
|
||||
myGUS.ActiveMask=0xffffffffU >> (32-myGUS.ActiveChannels);
|
||||
gus_chan->Enable(true);
|
||||
myGUS.basefreq = (Bit32u)((float)1000000/(1.619695497*(float)(myGUS.ActiveChannels)));
|
||||
myGUS.basefreq = (Bit32u)(0.5 + 1000000.0/(1.619695497*(double)(myGUS.ActiveChannels)));
|
||||
#if LOG_GUS
|
||||
LOG_MSG("GUS set to %d channels", myGUS.ActiveChannels);
|
||||
LOG_MSG("GUS set to %d channels, freq %d", myGUS.ActiveChannels, myGUS.basefreq);
|
||||
#endif
|
||||
for (i=0;i<myGUS.ActiveChannels;i++) guschan[i]->UpdateWaveRamp();
|
||||
break;
|
||||
|
|
@ -740,24 +770,17 @@ static void GUS_DMA_Callback(DmaChannel * chan,DMAEvent event) {
|
|||
}
|
||||
|
||||
static void GUS_CallBack(Bitu len) {
|
||||
memset(&MixTemp,0,len*8);
|
||||
Bitu i;
|
||||
Bit16s * buf16 = (Bit16s *)MixTemp;
|
||||
Bit32s * buf32 = (Bit32s *)MixTemp;
|
||||
for(i=0;i<myGUS.ActiveChannels;i++)
|
||||
guschan[i]->generateSamples(buf32,len);
|
||||
for(i=0;i<len*2;i++) {
|
||||
Bit32s sample=((buf32[i] >> 13)*AutoAmp)>>9;
|
||||
if (sample>32767) {
|
||||
sample=32767;
|
||||
AutoAmp--;
|
||||
} else if (sample<-32768) {
|
||||
sample=-32768;
|
||||
AutoAmp--;
|
||||
}
|
||||
buf16[i] = (Bit16s)(sample);
|
||||
Bit32s buffer[MIXER_BUFSIZE][2];
|
||||
memset(buffer, 0, len * sizeof(buffer[0]));
|
||||
|
||||
for (Bitu i = 0; i < myGUS.ActiveChannels; i++) {
|
||||
guschan[i]->generateSamples(buffer[0], len);
|
||||
}
|
||||
gus_chan->AddSamples_s16(len,buf16);
|
||||
for (Bitu i = 0; i < len; i++) {
|
||||
buffer[i][0] >>= VOL_SHIFT;
|
||||
buffer[i][1] >>= VOL_SHIFT;
|
||||
}
|
||||
gus_chan->AddSamples_s32(len, buffer[0]);
|
||||
CheckVoiceIrq();
|
||||
}
|
||||
|
||||
|
|
@ -768,10 +791,12 @@ static void MakeTables(void) {
|
|||
for (i=4095;i>=0;i--) {
|
||||
vol16bit[i]=(Bit16s)out;
|
||||
out/=1.002709201; /* 0.0235 dB Steps */
|
||||
//Original amplification routine in the hardware
|
||||
//vol16bit[i] = ((256 + i & 0xff) << VOL_SHIFT) / (1 << (24 - (i >> 8)));
|
||||
}
|
||||
pantable[0] = 4095 << RAMP_FRACT;
|
||||
for (i=1;i<16;i++) {
|
||||
pantable[i]=(Bit32u)(-128.0*(log((double)i/15.0)/log(2.0))*(double)(1 << RAMP_FRACT));
|
||||
pantable[i]=(Bit32u)(0.5-128.0*(log((double)i/15.0)/log(2.0))*(double)(1 << RAMP_FRACT));
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -874,7 +899,7 @@ public:
|
|||
|
||||
memset(&myGUS,0,sizeof(myGUS));
|
||||
memset(GUSRam,0,1024*1024);
|
||||
}
|
||||
}
|
||||
};
|
||||
|
||||
static GUS* test;
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue