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added 2 and 3 bit adpcm (Srecko)

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Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@1618
This commit is contained in:
Peter Veenstra 2004-01-28 19:42:08 +00:00
parent 66aa286476
commit 028737db18
1 changed files with 115 additions and 1 deletions
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116
src/hardware/sblaster.cpp
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@ -65,6 +65,8 @@ enum DSP_MODES {
enum DMA_MODES {
DMA_NONE,
DMA_8_SILENCE,
DMA_2_SINGLE,
DMA_3_SINGLE,
DMA_4_SINGLE,
DMA_8_SINGLE,DMA_8_AUTO,
DMA_16_SINGLE,DMA_16_AUTO,
@ -285,6 +287,34 @@ INLINE Bit16s decode_ADPCM_4_sample(Bit8u sample,Bits& reference,Bits& scale) {
#endif
INLINE Bit16s decode_ADPCM_2_sample(Bit8u sample,Bits& reference,Bits& scale) {
static Bits scaleMap[8] = { -2, -1, 0, 0, 1, 1, 1, 1 };
if (sample & 0x02) {
reference = max(0x00, reference - ((sample & 0x01) << (scale+2)));
} else {
reference = min(0xff, reference + ((sample & 0x01) << (scale+2)));
}
scale = max(2, min(6, scaleMap[sample & 0x07]));
return (((Bit8s)reference)^0x80)<<8;
}
INLINE Bit16s decode_ADPCM_3_sample(Bit8u sample,Bits& reference,Bits& scale) {
static Bits scaleMap[8] = { -2, -1, 0, 0, 1, 1, 1, 1 };
if (sample & 0x04) {
reference = max(0x00, reference - ((sample & 0x03) << (scale+1)));
} else {
reference = min(0xff, reference + ((sample & 0x03) << (scale+1)));
}
scale = max(2, min(6, scaleMap[sample & 0x07]));
return (((Bit8s)reference)^0x80)<<8;
}
static void GenerateDMASound(Bitu size) {
/* Check some variables */
if (!size) return;
@ -296,8 +326,72 @@ static void GenerateDMASound(Bitu size) {
#else
if (index<2000) size=sb.dma.left;
#endif
Bitu read,i;
Bitu read,i,ad;
switch (sb.dma.mode) {
case DMA_2_SINGLE:
if (sb.adpcm.reference==0x1000000 && sb.dma.left) {
Bit8u ref;
read=DMA_8_Read(sb.hw.dma8,&ref,1);
if (!read) { sb.mode=MODE_NONE;return; }
sb.dma.left--;
sb.adpcm.reference=0;
sb.adpcm.stepsize=MIN_ADAPTIVE_STEP_SIZE;
}
if (sb.dma.left<size) size=sb.dma.left;
read=DMA_8_Read(sb.hw.dma8,sb.dma.buf.b8,size);
sb.dma.left-=read;
if (sb.dma.left==0 || !read) {
sb.mode=MODE_NONE;
SB_RaiseIRQ(SB_IRQ_8);
}
for (i=0;i<read;i++) {
sb.tmp.buf.m[i*4+0]=decode_ADPCM_2_sample(sb.dma.buf.b8[i] >> 6,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*4+1]=decode_ADPCM_2_sample((sb.dma.buf.b8[i] >>4) & 0x3,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*4+2]=decode_ADPCM_2_sample((sb.dma.buf.b8[i] >>2)& 0x3,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*4+3]=decode_ADPCM_2_sample(sb.dma.buf.b8[i] & 0x3,sb.adpcm.reference,sb.adpcm.stepsize);
}
read*=4;
break;
case DMA_3_SINGLE:
if (sb.adpcm.reference==0x1000000 && sb.dma.left) {
Bit8u ref;
read=DMA_8_Read(sb.hw.dma8,&ref,1);
if (!read) { sb.mode=MODE_NONE;return;}
sb.dma.left--;
sb.adpcm.reference=0;
sb.adpcm.stepsize=MIN_ADAPTIVE_STEP_SIZE;
}
if (sb.dma.left<size) size=sb.dma.left;
read=DMA_8_Read(sb.hw.dma8,sb.dma.buf.b8,size);
sb.dma.left-=read;
if (sb.dma.left==0 || !read) {
sb.mode=MODE_NONE;
SB_RaiseIRQ(SB_IRQ_8);
}
ad=read%3;read/=3;
for (i=0;i<read;i++) {
sb.tmp.buf.m[i*8+0]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3])&7, sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+1]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3]>>3)&7, sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+2]=decode_ADPCM_3_sample(((sb.dma.buf.b8[i*3] >>6)&3)&((sb.dma.buf.b8[i*3+1]&1)<<2),sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+3]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3+1]>>1)&7,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+4]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3+1]>>4)&7,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+5]=decode_ADPCM_3_sample(((sb.dma.buf.b8[i*3+1]>>7)&1)&((sb.dma.buf.b8[i*3+2]&3)<<1),sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+6]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3+2]>>2)&7,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[i*8+7]=decode_ADPCM_3_sample((sb.dma.buf.b8[i*3+2]>>5)&7,sb.adpcm.reference,sb.adpcm.stepsize);
}
read*=8;
if (ad) {
sb.tmp.buf.m[read]=decode_ADPCM_3_sample((sb.dma.buf.b8[read*3/8])&7,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[read+1]=decode_ADPCM_3_sample((sb.dma.buf.b8[read*3/8]>>3)&7,sb.adpcm.reference,sb.adpcm.stepsize);
read+=2;
if (ad==2) {
sb.tmp.buf.m[read]=decode_ADPCM_3_sample(((sb.dma.buf.b8[(read-2)*3/8-1]>>6)&3)&(sb.dma.buf.b8[read*3/8]&1), sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[read+1]=decode_ADPCM_3_sample((sb.dma.buf.b8[(read-2)*3/8]>>1)&7,sb.adpcm.reference,sb.adpcm.stepsize);
sb.tmp.buf.m[read+2]=decode_ADPCM_3_sample((sb.dma.buf.b8[(read-2)*3/8]>>4)&7,sb.adpcm.reference,sb.adpcm.stepsize);
read+=3;
}
}
break;
case DMA_4_SINGLE:
if (sb.adpcm.reference==0x1000000 && sb.dma.left) {
//TODO Check this
@ -489,6 +583,14 @@ static void DSP_StartDMATranfser(DMA_MODES mode) {
type="4-Bit ADPCM Single Cycle";
sb.tmp.add_index=(sb.dma.rate<<16)/sb.hw.rate;
break;
case DMA_3_SINGLE:
type="3-Bit ADPCM Single Cycle";
sb.tmp.add_index=(sb.dma.rate<<16)/sb.hw.rate;
break;
case DMA_2_SINGLE:
type="2-Bit ADPCM Single Cycle";
sb.tmp.add_index=(sb.dma.rate<<16)/sb.hw.rate;
break;
default:
LOG(LOG_SB,LOG_ERROR)("DSP:Illegal transfer mode %d",mode);
return;
@ -594,6 +696,18 @@ static void DSP_DoCommand(void) {
sb.dma.total=1+sb.dsp.in.data[0]+(sb.dsp.in.data[1] << 8);
DSP_StartDMATranfser(DMA_4_SINGLE);
break;
case 0x77: /* 074h : Single Cycle 3-bit(2.6bit) ADPCM Reference*/
sb.adpcm.reference=0x1000000;
case 0x76: /* 074h : Single Cycle 3-bit(2.6bit) ADPCM */
sb.dma.total=1+sb.dsp.in.data[0]+(sb.dsp.in.data[1] << 8);
DSP_StartDMATranfser(DMA_3_SINGLE);
break;
case 0x17: /* 074h : Single Cycle 2-bit ADPCM Reference*/
sb.adpcm.reference=0x1000000;
case 0x16: /* 074h : Single Cycle 2-bit ADPCM */
sb.dma.total=1+sb.dsp.in.data[0]+(sb.dsp.in.data[1] << 8);
DSP_StartDMATranfser(DMA_2_SINGLE);
break;
case 0x80: /* Silence DAC */
sb.dma.total=1+sb.dsp.in.data[0]+(sb.dsp.in.data[1] << 8);
DSP_StartDMATranfser(DMA_8_SILENCE);