/*
AppleWin : An Apple //e emulator for Windows
Copyright (C) 1994-1996, Michael O'Brien
Copyright (C) 1999-2001, Oliver Schmidt
Copyright (C) 2002-2005, Tom Charlesworth
Copyright (C) 2006-2007, Tom Charlesworth, Michael Pohoreski
AppleWin is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
AppleWin is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with AppleWin; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* Description: Speaker emulation
*
* Author: Various
*/
/* Remake for SDL Audio for Linux (or other SDL-compliant OSes) by beom beotiger --bb */
#include "stdafx.h"
// for _ASSERT ion. (here _ASSERT means Unix(tm) assert) --bb
#include <assert.h>
// Notes:
//
// [OLD: 23.191 Apple CLKs == 44100Hz (CLK_6502/44100)]
// 23 Apple CLKS per PC sample (played back at 44.1KHz)
//
//
// The speaker's wave output drives how much 6502 emulation is done in real-time, eg:
// If the speaker's wave buffer is running out of sample-data, then more 6502 cycles
// need to be executed to top-up the wave buffer.
// This is in contrast to the AY8910 voices, which can simply generate more data if
// their buffers are running low.
// number of channels and buffer size for Apple][ Speakers
static const unsigned short g_nSPKR_NumChannels = 1;
//-------------------------------------
// Globals (SOUND_WAVE)
// GPH This "INIT" value is the actual sample data written to the speaker when
// it gets whapped with a BIT $C030. Note the output is always digital.
// The Apple II had no notion of volume or of looping waves, only the single
// "click" of the speaker. We set this to a value well under the maximum to
// provide headroom for mixing Mockingboard sound without causing peak clipping.
const short SPKR_DATA_INIT = (short)0x2000; // data written to speakers buffer
static short g_nSpeakerData = 0x0000; //SPKR_DATA_INIT;
static short *g_pSpeakerBuffer = NULL;
static UINT g_nBufferIdx = 0;
static short *g_pStereoBuffer = NULL; // buffer for stereo samples
static short *g_pRemainderBuffer = NULL; // Remainder buffer
static UINT g_nRemainderBufferSize; // Setup in SpkrInitialize()
static UINT g_nRemainderBufferIdx; // Setup in SpkrInitialize()
// Application-wide globals:
DWORD soundtype = SOUND_WAVE; //default
double g_fClksPerSpkrSample; // Setup in SetClksPerSpkrSample()
// Globals
static unsigned __int64 g_nSpkrQuietCycleCount = 0;
static unsigned __int64 g_nSpkrLastCycle = 0;
static bool g_bSpkrToggleFlag = false;
static bool g_bSpkrAvailable = false;
static bool g_bSpkrRecentlyActive = false;
//-----------------------------------------------------------------------------
// Forward refs:
//ULONG Spkr_SubmitWaveBuffer_FullSpeed(short* pSpeakerBuffer, ULONG nNumSamples);
static ULONG Spkr_SubmitWaveBuffer(short* pSpeakerBuffer, ULONG nNumSamples);
static void Spkr_SetActive(bool bActive);
//=============================================================================
// Let us leave benchmark for the near future --bb ^_^
#if 0
static void DisplayBenchmarkResults ()
{
DWORD totaltime = GetTickCount() - extbench;
VideoRedrawScreen();
TCHAR buffer[64];
sprintf(buffer,
TEXT("This benchmark took %u.%02u seconds."),
(unsigned)(totaltime / 1000),
(unsigned)((totaltime / 10) % 100));
/* MessageBox(g_hFrameWindow,
buffer,
TEXT("Benchmark Results"),
MB_ICONINFORMATION | MB_SETFOREGROUND);*/
printf("This benchmark took %u.%02u seconds.",
(unsigned)(totaltime / 1000), (unsigned)((totaltime / 10) % 100));
}
#endif
//=============================================================================
static void SetClksPerSpkrSample()
{
// // 23.191 clks for 44.1Khz (when 6502 CLK=1.0Mhz)
// g_fClksPerSpkrSample = g_fCurrentCLK6502 / (double)SPKR_SAMPLE_RATE;
// Use integer value: Better for MJ Mahon's RT.SYNTH.DSK (integer multiples of 1.023MHz Clk)
// . 23 clks @ 1.023MHz SPKR_SAMPLE_RATE = 44100Hz!?
g_fClksPerSpkrSample = (double) (UINT) (g_fCurrentCLK6502 / (double)SPKR_SAMPLE_RATE);
}
//=============================================================================
static void InitRemainderBuffer()
{
delete [] g_pRemainderBuffer;
SetClksPerSpkrSample();
g_nRemainderBufferSize = (UINT) g_fClksPerSpkrSample;
if ((double)g_nRemainderBufferSize != g_fClksPerSpkrSample)
g_nRemainderBufferSize++;
g_pRemainderBuffer = new short [g_nRemainderBufferSize];
memset(g_pRemainderBuffer, 0, g_nRemainderBufferSize);
g_nRemainderBufferIdx = 0;
}
//
// ----- ALL GLOBALLY ACCESSIBLE FUNCTIONS ARE BELOW THIS LINE -----
//
//=============================================================================
void SpkrDestroy ()
{
Spkr_DSUninit();
if(soundtype == SOUND_WAVE)
{
delete [] g_pSpeakerBuffer;
delete [] g_pStereoBuffer;
delete [] g_pRemainderBuffer;
g_pSpeakerBuffer = NULL;
g_pStereoBuffer = NULL;
g_pRemainderBuffer = NULL;
}
}
//=============================================================================
void SpkrInitialize ()
{
if(g_fh)
{
fprintf(g_fh, "Spkr Config: soundtype = %d ", (int)soundtype);
switch(soundtype)
{
case SOUND_NONE: fprintf(g_fh, "(NONE)\n"); break;
case SOUND_WAVE: fprintf(g_fh, "(WAVE)\n"); break;
default: fprintf(g_fh, "(UNDEFINED!)\n"); break;
}
}
if(g_bDisableDirectSound)
{
// SpeakerVoice.bMute = true;
}
else
{
//DSInit();
g_bSpkrAvailable = Spkr_DSInit();
}
if (soundtype == SOUND_WAVE)
{
InitRemainderBuffer();
// Buffer can hold a max of 1 seconds worth of samples
g_pSpeakerBuffer = new short [SPKR_SAMPLE_RATE];
g_pStereoBuffer = new short [SPKR_SAMPLE_RATE * 2]; // doubled for stereo
}
}
//=============================================================================
// NB. Called when /g_fCurrentCLK6502/ changes
void SpkrReinitialize ()
{
if (soundtype == SOUND_WAVE)
{
InitRemainderBuffer();
}
}
//=============================================================================
void SpkrReset()
{
g_nBufferIdx = 0;
g_nSpkrQuietCycleCount = 0;
g_bSpkrToggleFlag = false;
InitRemainderBuffer();
Spkr_SubmitWaveBuffer(NULL, 0);
Spkr_SetActive(false);
Spkr_Demute();
}
//=================2012 AD =========================================================
#if 0
BOOL SpkrSetEmulationType (DWORD newtype)
{
if (soundtype != SOUND_NONE)
SpkrDestroy();
soundtype = newtype;
if (soundtype != SOUND_NONE)
SpkrInitialize();
if (soundtype != newtype)
switch (newtype) { // some fault occured
case SOUND_WAVE:
/* MessageBox(window,
TEXT("The emulator is unable to initialize a waveform ")
TEXT("output device. Make sure you have a sound card ")
TEXT("and a driver installed and that windows is ")
TEXT("correctly configured to use the driver. Also ")
TEXT("ensure that no other program is currently using ")
TEXT("the device."),
TEXT("Configuration"),
MB_ICONEXCLAMATION | MB_SETFOREGROUND);*/
// Need to tuck SDL_GetError() hhere? ------------------------------------------
fprintf(stderr, "Unable to initialize a waveform output device.\n");
return 0;
}
return 1;
}
#endif
//=============================================================================
static void ReinitRemainderBuffer(UINT nCyclesRemaining)
{
if(nCyclesRemaining == 0)
return;
for(g_nRemainderBufferIdx=0; g_nRemainderBufferIdx<nCyclesRemaining; g_nRemainderBufferIdx++)
g_pRemainderBuffer[g_nRemainderBufferIdx] = g_nSpeakerData;
_ASSERT(g_nRemainderBufferIdx < g_nRemainderBufferSize);
}
static void UpdateRemainderBuffer(ULONG* pnCycleDiff)
{
if(g_nRemainderBufferIdx)
{
while((g_nRemainderBufferIdx < g_nRemainderBufferSize) && *pnCycleDiff)
{
g_pRemainderBuffer[g_nRemainderBufferIdx] = g_nSpeakerData;
g_nRemainderBufferIdx++;
(*pnCycleDiff)--;
}
if(g_nRemainderBufferIdx == g_nRemainderBufferSize)
{
g_nRemainderBufferIdx = 0;
signed long nSampleMean = 0;
for(UINT i=0; i<g_nRemainderBufferSize; i++)
nSampleMean += (signed long) g_pRemainderBuffer[i];
nSampleMean /= (signed long) g_nRemainderBufferSize;
if(g_nBufferIdx < SPKR_SAMPLE_RATE-1)
g_pSpeakerBuffer[g_nBufferIdx++] = (short) nSampleMean;
}
}
}
static void UpdateSpkr()
{
if(!g_bFullSpeed /*|| SoundCore_GetTimerState()*/)
{
ULONG nCycleDiff = (ULONG) (g_nCumulativeCycles - g_nSpkrLastCycle);
UpdateRemainderBuffer(&nCycleDiff);
ULONG nNumSamples = (ULONG) ((double)nCycleDiff / g_fClksPerSpkrSample);
ULONG nCyclesRemaining = (ULONG) ((double)nCycleDiff - (double)nNumSamples * g_fClksPerSpkrSample);
while((nNumSamples--) && (g_nBufferIdx < SPKR_SAMPLE_RATE-1)) {
g_pSpeakerBuffer[g_nBufferIdx++] = g_nSpeakerData;
}
ReinitRemainderBuffer(nCyclesRemaining); // Partially fill 1Mhz sample buffer
}
g_nSpkrLastCycle = g_nCumulativeCycles;
// GPH Added - simulate decoupling capacitor - use approximate value
//g_nSpeakerData = (short)((double) g_nSpeakerData * 0.995);
}
//=============================================================================
// Called by emulation code when Speaker I/O reg (0xC030) is accessed
BYTE SpkrToggle (WORD, WORD, BYTE, BYTE, ULONG nCyclesLeft)
{
g_bSpkrToggleFlag = true;
if(!g_bFullSpeed)
Spkr_SetActive(true);
needsprecision = cumulativecycles; // ?
// if (extbench)
// {
// DisplayBenchmarkResults();
// extbench = 0;
// }
if (soundtype == SOUND_WAVE)
{
CpuCalcCycles(nCyclesLeft);
UpdateSpkr();
g_nSpeakerData = g_nSpeakerData ^ SPKR_DATA_INIT; //~g_nSpeakerData;
// printf("SpkrToggle: %04x\n",g_nSpeakerData);
}
return MemReadFloatingBus(nCyclesLeft); // reading from $C030..$C03F retrurns unpredictable value?
}
//=============================================================================
// Called by ContinueExecution()
void SpkrUpdate (DWORD totalcycles)
{
if(!g_bSpkrToggleFlag)
{
if(!g_nSpkrQuietCycleCount)
{
g_nSpkrQuietCycleCount = g_nCumulativeCycles;
}
else if(g_nCumulativeCycles - g_nSpkrQuietCycleCount > (unsigned __int64)g_fCurrentCLK6502/5)
{
// After 0.2 sec of Apple time, deactivate spkr voice
// . This allows emulator to auto-switch to full-speed g_nAppMode for fast disk access
Spkr_SetActive(false);
}
}
else
{
g_nSpkrQuietCycleCount = 0;
g_bSpkrToggleFlag = false;
}
if (soundtype == SOUND_WAVE)
{
UpdateSpkr();
ULONG nSamplesUsed;
if(g_bFullSpeed) g_nBufferIdx = 0; // try this --bb
// nSamplesUsed = Spkr_SubmitWaveBuffer/*_FullSpeed*/(g_pSpeakerBuffer, g_nBufferIdx);
else {
nSamplesUsed = Spkr_SubmitWaveBuffer(g_pSpeakerBuffer, g_nBufferIdx);
_ASSERT(nSamplesUsed <= g_nBufferIdx);
if(nSamplesUsed == 0) return;
memmove(g_pSpeakerBuffer, &g_pSpeakerBuffer[nSamplesUsed], g_nBufferIdx-nSamplesUsed);
g_nBufferIdx -= nSamplesUsed;
}
}
}
//=============================================================================
//-----------------------------------------------------------------------------
static ULONG Spkr_SubmitWaveBuffer(short* pSpeakerBuffer, ULONG nNumSamples)
{
// submit nNumSamples (== 2bytes long each (sizeof short))??
// from pSpeakerBuffer to pDSSpkrBuf for callback DSPlaySnd
// if(!g_bSpkrRecentlyActive) return nNumSamples;//if not active, just return?
if(pSpeakerBuffer == NULL)
{
// just init sound buffer and cursors??
return 0;
}
// Convert mono Speakers sounds to stereo (mainly for Mockingboard support)
UINT len = nNumSamples * 2; // stereo = 2 * mono
UINT i;
for(i = 0; i < len; i += 2)
{
g_pStereoBuffer[i] = g_pStereoBuffer[i + 1] = pSpeakerBuffer[i >> 1];
}
// use code from OpenMSX
// DSUploadBuffer(pSpeakerBuffer, nNumSamples);
DSUploadBuffer(g_pStereoBuffer, len); // submit stereo wave data
return nNumSamples; // always return as if we've filled everything!? --bb
}
///////////// Mute - set volume to MINIMUM, Demute - set volume to NORMAL STATE? -bb
void Spkr_Mute()
{
SDL_PauseAudio(1); // dangerous functiouse - will mute Mockingboard, too. Need to be changed
}
void Spkr_Demute()
{
SDL_PauseAudio(0);
}
//-----------------------------------------------------------------------------
static void Spkr_SetActive(bool bActive)
{ // yes, I know the right way is: g_bSpkrRecentlyActive = bActive;, but... ^_^ --bb
if(bActive)
{
// Called by SpkrToggle() or SpkrReset()
g_bSpkrRecentlyActive = true;
}
else
{
// Called by SpkrUpdate() after 0.2s of speaker inactivity
g_bSpkrRecentlyActive = false;
}
}
bool Spkr_IsActive()
{
return g_bSpkrRecentlyActive;
}
//-----------------------------------------------------------------------------
// How to deal with volume in SDL Audio
// may be need to go to SDL Mixer?
DWORD SpkrGetVolume()
{
// return SpeakerVoice.dwUserVolume;
return 0;
}
void SpkrSetVolume(DWORD dwVolume, DWORD dwVolumeMax)
{
/* SpeakerVoice.dwUserVolume = dwVolume;
SpeakerVoice.nVolume = NewVolume(dwVolume, dwVolumeMax);
if(SpeakerVoice.bActive)
SpeakerVoice.lpDSBvoice->SetVolume(SpeakerVoice.nVolume);*/
}
//=============================================================================
bool Spkr_DSInit()
{
//
// Create single Apple speaker voice
//
if(!g_bDSAvailable)
return false; // do not have DirectSound? Sorry, SDL Audio! ^_^ --bb
return true;
}
void Spkr_DSUninit()
{
}
//=============================================================================
DWORD SpkrGetSnapshot(SS_IO_Speaker* pSS)
{
pSS->g_nSpkrLastCycle = g_nSpkrLastCycle;
return 0;
}
DWORD SpkrSetSnapshot(SS_IO_Speaker* pSS)
{
g_nSpkrLastCycle = pSS->g_nSpkrLastCycle;
return 0;
}