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[openMSX-commits] CVS: openMSX/src/sound SCC.cc,1.12,1.13 SCC.hh,1.7,1.8
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From: Wouter V. <m97...@us...> - 2003-02-24 20:30:03
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Update of /cvsroot/openmsx/openMSX/src/sound
In directory sc8-pr-cvs1:/tmp/cvs-serv14940/src/sound
Modified Files:
SCC.cc SCC.hh
Log Message:
Implemented Jon's SCC amplitude measurements
Index: SCC.cc
===================================================================
RCS file: /cvsroot/openmsx/openMSX/src/sound/SCC.cc,v
retrieving revision 1.12
retrieving revision 1.13
diff -u -d -r1.12 -r1.13
--- SCC.cc 2 Feb 2003 14:38:37 -0000 1.12
+++ SCC.cc 24 Feb 2003 20:29:58 -0000 1.13
@@ -1,7 +1,39 @@
// $Id$
-#include "SCC.hh"
+//----------------------------------------------------------------------------
+//
+// On Mon, 24 Feb 2003, Jon De Schrijder wrote:
+//
+// I've done some measurements with the scope on the output of the SCC.
+// I didn't do timing tests, only amplitude checks:
+//
+// I know now for sure, the amplitude calculation works as follows:
+//
+// AmpOut=640+AmpA+AmpB+AmpC+AmpD+AmpE
+//
+// range AmpOut (11 bits positive number=SCC digital output): [+40...+1235]
+//
+// AmpA="((SampleValue*VolA) AND #7FF0) div 16"
+// AmpB="((SampleValue*VolB) AND #7FF0) div 16"
+// AmpC="((SampleValue*VolC) AND #7FF0) div 16"
+// AmpD="((SampleValue*VolD) AND #7FF0) div 16"
+// AmpE="((SampleValue*VolE) AND #7FF0) div 16"
+//
+// Setting the enablebit to zero, corresponds with VolX=0.
+//
+// SampleValue range [-128...+127]
+// VolX range [0..15]
+//
+// Notes:
+// * SampleValue*VolX is calculated (signed multiplication) and the lower 4
+// bits are dropped (both in case the value is positive or negative), before
+// the addition of the 5 values is done. This was tested by setting
+// SampleValue=+1 and VolX=15 of different channels. The resulting AmpOut=640,
+// indicating that the 4 lower bits were dropped *before* the addition.
+//
+//----------------------------------------------------------------------------
+#include "SCC.hh"
#include "Mixer.hh"
@@ -23,7 +55,6 @@
byte SCC::readMemInterface(byte address, const EmuTime &time)
{
- //PRT_DEBUG("SCC read " << std::hex << (int)address << std::dec);
return memInterface[address];
}
@@ -36,65 +67,68 @@
switch (chip) {
case SCC_Real:
// Simply mask upper 128 bytes
- for (int i=0x80; i<=0xFF; i++)
+ for (int i = 0x80; i <= 0xFF; i++) {
memInterface[i] = 0xFF;
+ }
break;
case SCC_Compatible:
// 32 bytes Frequency Volume data
getFreqVol(0x80);
// 32 bytes waveform five
- for (int i=0; i<=0x1F; i++)
- memInterface[0xA0+i] = wave[4][i];
+ for (int i = 0; i <= 0x1F; i++) {
+ memInterface[0xA0 + i] = wave[4][i];
+ }
// 32 bytes deform register
getDeform(0xC0);
// no function area
- for (int i=0xE0; i<=0xFF; i++)
+ for (int i = 0xE0; i <= 0xFF; i++) {
memInterface[i] = 0xFF;
+ }
break;
case SCC_plusmode:
// 32 bytes waveform five
- for (int i=0; i<=0x1F; i++)
- memInterface[0x80+i] = wave[4][i];
+ for (int i = 0; i <= 0x1F; i++) {
+ memInterface[0x80 + i] = wave[4][i];
+ }
// 32 bytes Frequency Volume data
getFreqVol(0xA0);
// 32 bytes deform register
getDeform(0xC0);
// no function area
- for (int i=0xE0; i<=0xFF; i++)
+ for (int i = 0xE0; i <= 0xFF; i++) {
memInterface[i] = 0xFF;
+ }
}
}
void SCC::getDeform(byte offset)
{
// 32 bytes deform register
- for (int i=0; i<=0x1F; i++)
+ for (int i = 0; i <= 0x1F; i++) {
memInterface[i + offset] = deformationRegister;
+ }
}
void SCC::getFreqVol(byte offset)
{
// 32 bytes Frequency Volume data
// Take care of the mirroring
- for (int i=0; i<10; i++) {
+ for (int i = 0; i < 10; i++) {
memInterface[offset + i] =
memInterface[offset + i + 16] =
(i & 1) ? freq[i / 2] >> 8 : freq[i / 2] & 0xFF;
}
for (int i = 0; i < 5; i++) {
memInterface[offset + i + 10] =
- memInterface[offset + i + 10 + 16] =
- volume[i];
+ memInterface[offset + i + 10 + 16] = volume[i];
}
memInterface[offset + 15] =
- memInterface[offset + 31] =
- ch_enable;
+ memInterface[offset + 31] = ch_enable;
}
void SCC::writeMemInterface(byte address, byte value, const EmuTime &time)
{
- //PRT_DEBUG("SCC write " << std::hex <<(int)address << " " << (int)value << std::dec);
Mixer::instance()->updateStream(time);
byte waveborder = (currentChipMode == SCC_plusmode) ? 0xA0 : 0x80;
@@ -104,13 +138,17 @@
int ch = address >> 5;
//if (!rotate[ch]) {
// TODO: Need to figure this noise thing out
- // Don't know why but japanese doesn't change wave when noise is enabled ??
- wave[ch][address & 0x1F] = value;
- volAdjustedWave[ch][address & 0x1F] = ((signed_byte)value * volume[ch] * masterVolume) / 2048;
+ // Don't know why but japanese doesn't change wave
+ // when noise is enabled ??
+ wave[ch][address & 0x1F] = value;
+ int tmp = ((signed_byte)value * volume[ch]) / 16;
+ volAdjustedWave[ch][address & 0x1F] =
+ (tmp * masterVolume) / 256;
if ((currentChipMode != SCC_plusmode) && (ch == 3)) {
// copy waveform 4 -> waveform 5
- wave[4][address & 0x1F] = wave[ch][address & 0x1F];
- volAdjustedWave[4][address & 0x1F] = volAdjustedWave[ch][address & 0x1F];
+ wave[4][address & 0x1F] = wave[ch][address & 0x1F];
+ volAdjustedWave[4][address & 0x1F] =
+ volAdjustedWave[ch][address & 0x1F];
}
//}
@@ -135,8 +173,9 @@
memInterface[address & 0xEF] = value;
} else if ((address >= 0xC0) && (address < 0xE0)) {
setDeformReg(value);
- for (int i=0xC0; i<=0xE0; i++)
+ for (int i = 0xC0; i <= 0xE0; i++) {
memInterface[i] = value;
+ }
}
break;
case SCC_plusmode:
@@ -146,8 +185,9 @@
memInterface[address & 0xEF] = value;
} else if ((address >= 0xC0) && (address < 0xE0)) {
setDeformReg(value);
- for (int i=0xC0; i<=0xE0; i++)
+ for (int i = 0xC0; i <= 0xE0; i++) {
memInterface[i] = value;
+ }
}
}
}
@@ -163,37 +203,44 @@
* Didn't take time to integrate in my method so far
* According to sean these bits should produce noise on the channels
*/
- //for (int ch = 0; ch < 5; ch++)
+ //for (int ch = 0; ch < 5; ch++) {
// rotate[ch] = (value & 0x40) ? 0x1F: 0;
- //if (value & 0x80)
+ //}
+ //if (value & 0x80) {
// rotate[3] = rotate[4] = 0x1F;
+ //}
}
void SCC::setFreqVol(byte value, byte address)
{
- address &= 0x0f; // regio is twice visible
- if (address < 0x0a) {
+ address &= 0x0F; // regio is twice visible
+ if (address < 0x0A) {
// change frequency
byte channel = address / 2;
- if (address & 1)
- freq[channel] = ((value & 0xf)<<8) | (freq[channel] & 0xff);
- else
- freq[channel] = (freq[channel] & 0xf00) | (value & 0xff);
- if (refresh)
+ if (address & 1) {
+ freq[channel] = ((value & 0xF) << 8) | (freq[channel] & 0xFF);
+ } else {
+ freq[channel] = (freq[channel] & 0xF00) | (value & 0xFF);
+ }
+ if (refresh) {
count[channel] = 0;
+ }
unsigned frq = freq[channel];
- if (cycle_8bit)
- frq &= 0xff;
- if (cycle_4bit)
+ if (cycle_8bit) {
+ frq &= 0xFF;
+ }
+ if (cycle_4bit) {
frq >>= 8;
+ }
incr[channel] = (frq <= 8) ? 0 : (2 << GETA_BITS) / (frq + 1);
- }
- else if (address < 0x0f) {
+ } else if (address < 0x0F) {
// change volume
- byte channel = address - 0x0a;
- volume[channel] = value & 0xf;
- for (int i=0; i<32; i++)
- volAdjustedWave[channel][i] = ((signed_byte)(wave[channel][i]) * volume[channel] * masterVolume) / 2048;
+ byte channel = address - 0x0A;
+ volume[channel] = value & 0xF;
+ for (int i = 0; i < 32; i++) {
+ int tmp = ((signed_byte)wave[channel][i] * volume[channel]) / 16;
+ volAdjustedWave[channel][i] = (tmp * masterVolume) / 256;
+ }
checkMute();
} else {
// change enable-bits
@@ -208,8 +255,8 @@
setChipMode(SCC_Real);
deformationRegister = 0;
- for (int i=0; i<5; i++) {
- for (int j=0; j<32 ; j++) {
+ for (int i = 0; i < 5; i++) {
+ for (int j = 0; j < 32; j++) {
wave[i][j] = 0;
volAdjustedWave[i][j] = 0;
}
@@ -218,7 +265,7 @@
volume[i] = 0;
//rotate[i] = 0;
}
- ch_enable = 0xff;
+ ch_enable = 0xFF;
cycle_4bit = false;
cycle_8bit = false;
refresh = false;
@@ -239,9 +286,7 @@
int *SCC::updateBuffer(int length)
{
- //PRT_DEBUG("SCC: updateBuffer called");
if (isInternalMuted()) {
- //PRT_DEBUG("SCC: muted");
return NULL;
}
@@ -278,6 +323,5 @@
enable >>= 1;
volumePtr++;
}
- //PRT_DEBUG("SCC: setInternalMute(" << mute << "); ");
setInternalMute(mute);
}
Index: SCC.hh
===================================================================
RCS file: /cvsroot/openmsx/openMSX/src/sound/SCC.hh,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -d -r1.7 -r1.8
--- SCC.hh 16 Oct 2002 08:46:43 -0000 1.7
+++ SCC.hh 24 Feb 2003 20:29:59 -0000 1.8
@@ -3,14 +3,9 @@
#ifndef __SCC_HH__
#define __SCC_HH__
-#ifndef VERSION
-#include "config.h"
-#endif
-
#include "openmsx.hh"
#include "SoundDevice.hh"
-// forward declarations
class EmuTime;
@@ -25,7 +20,8 @@
// interaction with realCartridge
void reset();
byte readMemInterface(byte address,const EmuTime &time);
- void writeMemInterface(byte address, byte value,const EmuTime &time);
+ void writeMemInterface(byte address, byte value,
+ const EmuTime &time);
void setChipMode(ChipMode chip);
// SoundDevice
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