ref: 26658f1045a1e336a10039c0869eda27b34c6eb1
dir: /Game/src/audiolib/pas16.c/
/*
Copyright (C) 1994-1995 Apogee Software, Ltd.
This program 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.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/**********************************************************************
module: PAS16.C
author: James R. Dose
date: March 27, 1994
Low level routines to support Pro AudioSpectrum and compatible
sound cards.
(c) Copyright 1994 James R. Dose. All Rights Reserved.
**********************************************************************/
#include <dos.h>
#include <conio.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "dpmi.h"
#include "dma.h"
#include "interrup.h"
#include "irq.h"
#include "pas16.h"
#include "_pas16.h"
#define USESTACK
static const int PAS_Interrupts[ PAS_MaxIrq + 1 ] =
{
INVALID, INVALID, 0xa, 0xb,
INVALID, 0xd, INVALID, 0xf,
INVALID, INVALID, 0x72, 0x73,
0x74, INVALID, INVALID, 0x77
};
static void ( interrupt far *PAS_OldInt )( void );
static int PAS_IntController1Mask;
static int PAS_IntController2Mask;
static int PAS_Installed = FALSE;
static int PAS_TranslateCode = DEFAULT_BASE;
static int PAS_OriginalPCMLeftVolume = 75;
static int PAS_OriginalPCMRightVolume = 75;
static int PAS_OriginalFMLeftVolume = 75;
static int PAS_OriginalFMRightVolume = 75;
unsigned int PAS_DMAChannel;
static int PAS_Irq;
static MVState *PAS_State = NULL;
static MVFunc *PAS_Func = NULL;
static MVState PAS_OriginalState;
static int PAS_SampleSizeConfig;
static char *PAS_DMABuffer;
static char *PAS_DMABufferEnd;
static char *PAS_CurrentDMABuffer;
static int PAS_TotalDMABufferSize;
static int PAS_TransferLength = 0;
static int PAS_MixMode = PAS_DefaultMixMode;
static unsigned PAS_SampleRate = PAS_DefaultSampleRate;
static int PAS_TimeInterval = 0;
volatile int PAS_SoundPlaying;
void ( *PAS_CallBack )( void );
// adequate stack size
#define kStackSize 2048
static unsigned short StackSelector = NULL;
static unsigned long StackPointer;
static unsigned short oldStackSelector;
static unsigned long oldStackPointer;
// This is defined because we can't create local variables in a
// function that switches stacks.
static int irqstatus;
// These declarations are necessary to use the inline assembly pragmas.
extern void GetStack(unsigned short *selptr,unsigned long *stackptr);
extern void SetStack(unsigned short selector,unsigned long stackptr);
// This function will get the current stack selector and pointer and save
// them off.
#pragma aux GetStack = \
"mov [edi],esp" \
"mov ax,ss" \
"mov [esi],ax" \
parm [esi] [edi] \
modify [eax esi edi];
// This function will set the stack selector and pointer to the specified
// values.
#pragma aux SetStack = \
"mov ss,ax" \
"mov esp,edx" \
parm [ax] [edx] \
modify [eax edx];
int PAS_ErrorCode = PAS_Ok;
#define PAS_SetErrorCode( status ) \
PAS_ErrorCode = ( status );
/*---------------------------------------------------------------------
Function: PAS_ErrorString
Returns a pointer to the error message associated with an error
number. A -1 returns a pointer the current error.
---------------------------------------------------------------------*/
char *PAS_ErrorString
(
int ErrorNumber
)
{
char *ErrorString;
switch( ErrorNumber )
{
case PAS_Warning :
case PAS_Error :
ErrorString = PAS_ErrorString( PAS_ErrorCode );
break;
case PAS_Ok :
ErrorString = "Pro AudioSpectrum ok.";
break;
case PAS_DriverNotFound :
ErrorString = "MVSOUND.SYS not loaded.";
break;
case PAS_DmaError :
ErrorString = DMA_ErrorString( DMA_Error );
break;
case PAS_InvalidIrq :
ErrorString = "Invalid Pro AudioSpectrum Irq.";
break;
case PAS_UnableToSetIrq :
ErrorString = "Unable to set Pro AudioSpectrum IRQ. Try selecting an IRQ of 7 or below.";
break;
case PAS_Dos4gwIrqError :
ErrorString = "Unsupported Pro AudioSpectrum Irq.";
break;
case PAS_NoSoundPlaying :
ErrorString = "No sound playing on Pro AudioSpectrum.";
break;
case PAS_CardNotFound :
ErrorString = "Could not find Pro AudioSpectrum.";
break;
case PAS_DPMI_Error :
ErrorString = "DPMI Error in PAS16.";
break;
case PAS_OutOfMemory :
ErrorString = "Out of conventional memory in PAS16.";
break;
default :
ErrorString = "Unknown Pro AudioSpectrum error code.";
break;
}
return( ErrorString );
}
/**********************************************************************
Memory locked functions:
**********************************************************************/
#define PAS_LockStart PAS_CheckForDriver
/*---------------------------------------------------------------------
Function: PAS_CheckForDriver
Checks to see if MVSOUND.SYS is installed.
---------------------------------------------------------------------*/
int PAS_CheckForDriver
(
void
)
{
union REGS regs;
unsigned result;
regs.w.ax = MV_CheckForDriver;
regs.w.bx = 0x3f3f;
#ifdef __386__
int386( MV_SoundInt, ®s, ®s );
#else
int86( MV_SoundInt, ®s, ®s );
#endif
if ( regs.w.ax != MV_CheckForDriver )
{
PAS_SetErrorCode( PAS_DriverNotFound );
return( PAS_Error );
}
result = regs.w.bx ^ regs.w.cx ^ regs.w.dx;
if ( result != MV_Signature )
{
PAS_SetErrorCode( PAS_DriverNotFound );
return( PAS_Error );
}
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_GetStateTable
Returns a pointer to the state table containing hardware state
information. The state table is necessary because the Pro Audio-
Spectrum contains only write-only registers.
---------------------------------------------------------------------*/
MVState *PAS_GetStateTable
(
void
)
{
union REGS regs;
MVState *ptr;
regs.w.ax = MV_GetPointerToStateTable;
#ifdef __386__
int386( MV_SoundInt, ®s, ®s );
#else
int86( MV_SoundInt, ®s, ®s );
#endif
if ( regs.w.ax != MV_Signature )
{
PAS_SetErrorCode( PAS_DriverNotFound );
return( NULL );
}
#if defined(__WATCOMC__) && defined(__FLAT__)
ptr = ( MVState * )( ( ( ( unsigned )regs.w.dx ) << 4 ) +
( ( unsigned )regs.w.bx ) );
#else
ptr = MK_FP( regs.w.dx, regs.w.bx );
#endif
return( ptr );
}
/*---------------------------------------------------------------------
Function: PAS_GetFunctionTable
Returns a pointer to the function table containing addresses of
driver functions.
---------------------------------------------------------------------*/
MVFunc *PAS_GetFunctionTable
(
void
)
{
union REGS regs;
MVFunc *ptr;
regs.w.ax = MV_GetPointerToFunctionTable;
#ifdef __386__
int386( MV_SoundInt, ®s, ®s );
#else
int86( MV_SoundInt, ®s, ®s );
#endif
if ( regs.w.ax != MV_Signature )
{
PAS_SetErrorCode( PAS_DriverNotFound );
return( NULL );
}
#if defined(__WATCOMC__) && defined(__FLAT__)
ptr = ( MVFunc * )( ( ( ( unsigned )regs.w.dx ) << 4 ) +
( ( unsigned )regs.w.bx ) );
#else
ptr = MK_FP( regs.w.dx, regs.w.bx );
#endif
return( ptr );
}
/*---------------------------------------------------------------------
Function: PAS_GetCardSettings
Returns the DMA and the IRQ channels of the sound card.
---------------------------------------------------------------------*/
int PAS_GetCardSettings
(
void
)
{
union REGS regs;
int status;
regs.w.ax = MV_GetDmaIrqInt;
#ifdef __386__
int386( MV_SoundInt, ®s, ®s );
#else
int86( MV_SoundInt, ®s, ®s );
#endif
if ( regs.w.ax != MV_Signature )
{
PAS_SetErrorCode( PAS_DriverNotFound );
return( PAS_Error );
}
PAS_DMAChannel = regs.w.bx;
PAS_Irq = regs.w.cx;
if ( PAS_Irq > PAS_MaxIrq )
{
PAS_SetErrorCode( PAS_Dos4gwIrqError );
return( PAS_Error );
}
if ( !VALID_IRQ( PAS_Irq ) )
{
PAS_SetErrorCode( PAS_InvalidIrq );
return( PAS_Error );
}
if ( PAS_Interrupts[ PAS_Irq ] == INVALID )
{
PAS_SetErrorCode( PAS_InvalidIrq );
return( PAS_Error );
}
status = DMA_VerifyChannel( PAS_DMAChannel );
if ( status == DMA_Error )
{
PAS_SetErrorCode( PAS_DmaError );
return( PAS_Error );
}
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_EnableInterrupt
Enables the triggering of the sound card interrupt.
---------------------------------------------------------------------*/
void PAS_EnableInterrupt
(
void
)
{
int mask;
int data;
unsigned flags;
flags = DisableInterrupts();
if ( PAS_Irq < 8 )
{
mask = inp( 0x21 ) & ~( 1 << PAS_Irq );
outp( 0x21, mask );
}
else
{
mask = inp( 0xA1 ) & ~( 1 << ( PAS_Irq - 8 ) );
outp( 0xA1, mask );
mask = inp( 0x21 ) & ~( 1 << 2 );
outp( 0x21, mask );
}
// Flush any pending interrupts
PAS_Write( InterruptStatus, PAS_Read( InterruptStatus ) & 0x40 );
// Enable the interrupt on the PAS
data = PAS_State->intrctlr;
data |= SampleBufferInterruptFlag;
PAS_Write( InterruptControl, data );
PAS_State->intrctlr = data;
RestoreInterrupts( flags );
}
/*---------------------------------------------------------------------
Function: PAS_DisableInterrupt
Disables the triggering of the sound card interrupt.
---------------------------------------------------------------------*/
void PAS_DisableInterrupt
(
void
)
{
int mask;
int data;
unsigned flags;
flags = DisableInterrupts();
// Disable the interrupt on the PAS
data = PAS_State->intrctlr;
data &= ~( SampleRateInterruptFlag | SampleBufferInterruptFlag );
PAS_Write( InterruptControl, data );
PAS_State->intrctlr = data;
// Restore interrupt mask
if ( PAS_Irq < 8 )
{
mask = inp( 0x21 ) & ~( 1 << PAS_Irq );
mask |= PAS_IntController1Mask & ( 1 << PAS_Irq );
outp( 0x21, mask );
}
else
{
mask = inp( 0x21 ) & ~( 1 << 2 );
mask |= PAS_IntController1Mask & ( 1 << 2 );
outp( 0x21, mask );
mask = inp( 0xA1 ) & ~( 1 << ( PAS_Irq - 8 ) );
mask |= PAS_IntController2Mask & ( 1 << ( PAS_Irq - 8 ) );
outp( 0xA1, mask );
}
RestoreInterrupts( flags );
}
/*---------------------------------------------------------------------
Function: PAS_ServiceInterrupt
Handles interrupt generated by sound card at the end of a voice
transfer. Calls the user supplied callback function.
---------------------------------------------------------------------*/
void interrupt far PAS_ServiceInterrupt
(
void
)
{
#ifdef USESTACK
// save stack
GetStack( &oldStackSelector, &oldStackPointer );
// set our stack
SetStack( StackSelector, StackPointer );
#endif
irqstatus = PAS_Read( InterruptStatus );
if ( ( irqstatus & SampleBufferInterruptFlag ) == 0 )
{
#ifdef USESTACK
// restore stack
SetStack( oldStackSelector, oldStackPointer );
#endif
_chain_intr( PAS_OldInt );
}
// Clear the interrupt
irqstatus &= ~SampleBufferInterruptFlag;
PAS_Write( InterruptStatus, irqstatus );
// send EOI to Interrupt Controller
if ( PAS_Irq > 7 )
{
outp( 0xA0, 0x20 );
}
outp( 0x20, 0x20 );
// Keep track of current buffer
PAS_CurrentDMABuffer += PAS_TransferLength;
if ( PAS_CurrentDMABuffer >= PAS_DMABufferEnd )
{
PAS_CurrentDMABuffer = PAS_DMABuffer;
}
// Call the caller's callback function
if ( PAS_CallBack != NULL )
{
PAS_CallBack();
}
#ifdef USESTACK
// restore stack
SetStack( oldStackSelector, oldStackPointer );
#endif
}
/*---------------------------------------------------------------------
Function: PAS_Write
Writes a byte of data to the sound card.
---------------------------------------------------------------------*/
void PAS_Write
(
int Register,
int Data
)
{
int port;
port = Register ^ PAS_TranslateCode;
outp( port, Data );
}
/*---------------------------------------------------------------------
Function: PAS_Read
Reads a byte of data from the sound card.
---------------------------------------------------------------------*/
int PAS_Read
(
int Register
)
{
int port;
int data;
port = Register ^ PAS_TranslateCode;
data = inp( port );
return( data );
}
/*---------------------------------------------------------------------
Function: PAS_SetSampleRateTimer
Programs the Sample Rate Timer.
---------------------------------------------------------------------*/
void PAS_SetSampleRateTimer
(
void
)
{
int LoByte;
int HiByte;
int data;
unsigned flags;
flags = DisableInterrupts();
// Disable the Sample Rate Timer
data = PAS_State->audiofilt;
data &= ~SampleRateTimerGateFlag;
PAS_Write( AudioFilterControl, data );
PAS_State->audiofilt = data;
// Select the Sample Rate Timer
data = SelectSampleRateTimer;
PAS_Write( LocalTimerControl, data );
PAS_State->tmrctlr = data;
LoByte = lobyte( PAS_TimeInterval );
HiByte = hibyte( PAS_TimeInterval );
// Program the Sample Rate Timer
PAS_Write( SampleRateTimer, LoByte );
PAS_Write( SampleRateTimer, HiByte );
PAS_State->samplerate = PAS_TimeInterval;
RestoreInterrupts( flags );
}
/*---------------------------------------------------------------------
Function: PAS_SetSampleBufferCount
Programs the Sample Buffer Count.
---------------------------------------------------------------------*/
void PAS_SetSampleBufferCount
(
void
)
{
int LoByte;
int HiByte;
int count;
int data;
unsigned flags;
flags = DisableInterrupts();
// Disable the Sample Buffer Count
data = PAS_State->audiofilt;
data &= ~SampleBufferCountGateFlag;
PAS_Write( AudioFilterControl, data );
PAS_State->audiofilt = data;
// Select the Sample Buffer Count
data = SelectSampleBufferCount;
PAS_Write( LocalTimerControl, data );
PAS_State->tmrctlr = data;
count = PAS_TransferLength;
// Check if we're using a 16-bit DMA channel
if ( PAS_DMAChannel > 3 )
{
count >>= 1;
}
LoByte = lobyte( count );
HiByte = hibyte( count );
// Program the Sample Buffer Count
PAS_Write( SampleBufferCount, LoByte );
PAS_Write( SampleBufferCount, HiByte );
PAS_State->samplecnt = count;
RestoreInterrupts( flags );
}
/*---------------------------------------------------------------------
Function: PAS_SetPlaybackRate
Sets the rate at which the digitized sound will be played in
hertz.
---------------------------------------------------------------------*/
void PAS_SetPlaybackRate
(
unsigned rate
)
{
if ( rate < PAS_MinSamplingRate )
{
rate = PAS_MinSamplingRate;
}
if ( rate > PAS_MaxSamplingRate )
{
rate = PAS_MaxSamplingRate;
}
PAS_TimeInterval = ( unsigned )CalcTimeInterval( rate );
if ( PAS_MixMode & STEREO )
{
PAS_TimeInterval /= 2;
}
// Keep track of what the actual rate is
PAS_SampleRate = CalcSamplingRate( PAS_TimeInterval );
if ( PAS_MixMode & STEREO )
{
PAS_SampleRate /= 2;
}
}
/*---------------------------------------------------------------------
Function: PAS_GetPlaybackRate
Returns the rate at which the digitized sound will be played in
hertz.
---------------------------------------------------------------------*/
unsigned PAS_GetPlaybackRate
(
void
)
{
return( PAS_SampleRate );
}
/*---------------------------------------------------------------------
Function: PAS_SetMixMode
Sets the sound card to play samples in mono or stereo.
---------------------------------------------------------------------*/
int PAS_SetMixMode
(
int mode
)
{
mode &= PAS_MaxMixMode;
// Check board revision. Revision # 0 can't play 16-bit data.
if ( ( PAS_State->intrctlr & 0xe0 ) == 0 )
{
// Force the mode to 8-bit data.
mode &= ~SIXTEEN_BIT;
}
PAS_MixMode = mode;
PAS_SetPlaybackRate( PAS_SampleRate );
return( mode );
}
/*---------------------------------------------------------------------
Function: PAS_StopPlayback
Ends the DMA transfer of digitized sound to the sound card.
---------------------------------------------------------------------*/
void PAS_StopPlayback
(
void
)
{
int data;
// Don't allow anymore interrupts
PAS_DisableInterrupt();
// Stop the transfer of digital data
data = PAS_State->crosschannel;
data &= PAS_PCMStopMask;
PAS_Write( CrossChannelControl, data );
PAS_State->crosschannel = data;
// Turn off 16-bit unsigned data
data = PAS_Read( SampleSizeConfiguration );
data &= PAS_SampleSizeMask;
PAS_Write( SampleSizeConfiguration, data );
// Disable the DMA channel
DMA_EndTransfer( PAS_DMAChannel );
PAS_SoundPlaying = FALSE;
PAS_DMABuffer = NULL;
}
/*---------------------------------------------------------------------
Function: PAS_SetupDMABuffer
Programs the DMAC for sound transfer.
---------------------------------------------------------------------*/
int PAS_SetupDMABuffer
(
char *BufferPtr,
int BufferSize,
int mode
)
{
int DmaStatus;
int data;
// Enable PAS Dma
data = PAS_State->crosschannel;
data |= PAS_DMAEnable;
PAS_Write( CrossChannelControl, data );
PAS_State->crosschannel = data;
DmaStatus = DMA_SetupTransfer( PAS_DMAChannel, BufferPtr, BufferSize, mode );
if ( DmaStatus == DMA_Error )
{
PAS_SetErrorCode( PAS_DmaError );
return( PAS_Error );
}
PAS_DMABuffer = BufferPtr;
PAS_CurrentDMABuffer = BufferPtr;
PAS_TotalDMABufferSize = BufferSize;
PAS_DMABufferEnd = BufferPtr + BufferSize;
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_GetCurrentPos
Returns the offset within the current sound being played.
---------------------------------------------------------------------*/
int PAS_GetCurrentPos
(
void
)
{
char *CurrentAddr;
int offset;
if ( !PAS_SoundPlaying )
{
PAS_SetErrorCode( PAS_NoSoundPlaying );
return( PAS_Error );
}
CurrentAddr = DMA_GetCurrentPos( PAS_DMAChannel );
if ( CurrentAddr == NULL )
{
PAS_SetErrorCode( PAS_DmaError );
return( PAS_Error );
}
offset = ( int )( ( ( unsigned long )CurrentAddr ) -
( ( unsigned long )PAS_CurrentDMABuffer ) );
if ( PAS_MixMode & SIXTEEN_BIT )
{
offset >>= 1;
}
if ( PAS_MixMode & STEREO )
{
offset >>= 1;
}
return( offset );
}
/*---------------------------------------------------------------------
Function: PAS_GetFilterSetting
Returns the bit settings for the appropriate filter level.
---------------------------------------------------------------------*/
int PAS_GetFilterSetting
(
int rate
)
{
/* CD Quality 17897hz */
if ( ( unsigned long )rate > ( unsigned long )17897L * 2 )
{
/* 00001b 20hz to 17.8khz */
return( 0x01 );
}
/* Cassette Quality 15090hz */
if ( ( unsigned long )rate > ( unsigned long )15909L * 2 )
{
/* 00010b 20hz to 15.9khz */
return( 0x02 );
}
/* FM Radio Quality 11931hz */
if ( ( unsigned long )rate > ( unsigned long )11931L * 2 )
{
/* 01001b 20hz to 11.9khz */
return( 0x09 );
}
/* AM Radio Quality 8948hz */
if ( ( unsigned long )rate > ( unsigned long )8948L * 2 )
{
/* 10001b 20hz to 8.9khz */
return( 0x11 );
}
/* Telphone Quality 5965hz */
if ( ( unsigned long )rate > ( unsigned long )5965L * 2 )
{
/* 00100b 20hz to 5.9khz */
return( 0x19 );
}
/* Male voice quality 2982hz */
/* 111001b 20hz to 2.9khz */
return( 0x04 );
}
/*---------------------------------------------------------------------
Function: PAS_BeginTransfer
Starts playback of digitized sound on the sound card.
---------------------------------------------------------------------*/
void PAS_BeginTransfer
(
int mode
)
{
int data;
PAS_SetSampleRateTimer();
PAS_SetSampleBufferCount();
PAS_EnableInterrupt();
// Get sample size configuration
data = PAS_Read( SampleSizeConfiguration );
// Check board revision. Revision # 0 can't play 16-bit data.
if ( PAS_State->intrctlr & 0xe0 )
{
data &= PAS_SampleSizeMask;
// set sample size bit
if ( PAS_MixMode & SIXTEEN_BIT )
{
data |= PAS_16BitSampleFlag;
}
}
// set oversampling rate
data &= PAS_OverSamplingMask;
data |= PAS_4xOverSampling;
// Set sample size configuration
PAS_Write( SampleSizeConfiguration, data );
// Get Cross channel setting
data = PAS_State->crosschannel;
data &= PAS_ChannelConnectMask;
if ( mode == RECORD )
{
data |= PAS_PCMStartADC;
}
else
{
data |= PAS_PCMStartDAC;
}
// set stereo mode bit
if ( !( PAS_MixMode & STEREO ) )
{
data |= PAS_StereoFlag;
}
PAS_Write( CrossChannelControl, data );
PAS_State->crosschannel = data;
// Get the filter appropriate filter setting
data = PAS_GetFilterSetting( PAS_SampleRate );
// Enable the Sample Rate Timer and Sample Buffer Count
data |= SampleRateTimerGateFlag | SampleBufferCountGateFlag;
if ( mode != RECORD )
{
// Enable audio (not Audio Mute)
data |= PAS_AudioMuteFlag;
}
PAS_Write( AudioFilterControl, data );
PAS_State->audiofilt = data;
PAS_SoundPlaying = TRUE;
}
/*---------------------------------------------------------------------
Function: PAS_BeginBufferedPlayback
Begins multibuffered playback of digitized sound on the sound card.
---------------------------------------------------------------------*/
int PAS_BeginBufferedPlayback
(
char *BufferStart,
int BufferSize,
int NumDivisions,
unsigned SampleRate,
int MixMode,
void ( *CallBackFunc )( void )
)
{
int DmaStatus;
PAS_StopPlayback();
PAS_SetMixMode( MixMode );
PAS_SetPlaybackRate( SampleRate );
PAS_TransferLength = BufferSize / NumDivisions;
PAS_SetCallBack( CallBackFunc );
DmaStatus = PAS_SetupDMABuffer( BufferStart, BufferSize, DMA_AutoInitRead );
if ( DmaStatus == PAS_Error )
{
return( PAS_Error );
}
PAS_BeginTransfer( PLAYBACK );
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_BeginBufferedRecord
Begins multibuffered recording of digitized sound on the sound card.
---------------------------------------------------------------------*/
int PAS_BeginBufferedRecord
(
char *BufferStart,
int BufferSize,
int NumDivisions,
unsigned SampleRate,
int MixMode,
void ( *CallBackFunc )( void )
)
{
int DmaStatus;
PAS_StopPlayback();
PAS_SetMixMode( MixMode );
PAS_SetPlaybackRate( SampleRate );
PAS_TransferLength = BufferSize / NumDivisions;
PAS_SetCallBack( CallBackFunc );
DmaStatus = PAS_SetupDMABuffer( BufferStart, BufferSize, DMA_AutoInitWrite );
if ( DmaStatus == PAS_Error )
{
return( PAS_Error );
}
PAS_BeginTransfer( RECORD );
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_CallInt
Calls interrupt 2fh.
---------------------------------------------------------------------*/
int PAS_CallInt( int ebx, int ecx, int edx );
#pragma aux PAS_CallInt = \
"int 2fh", \
parm [ ebx ] [ ecx ] [ edx ] modify exact [ eax ebx ecx edx esi edi ] value [ ebx ];
/*---------------------------------------------------------------------
Function: PAS_CallMVFunction
Performs a call to a real mode function.
---------------------------------------------------------------------*/
int PAS_CallMVFunction
(
unsigned long function,
int ebx,
int ecx,
int edx
)
{
dpmi_regs callregs;
int status;
callregs.EBX = ebx;
callregs.ECX = ecx;
callregs.EDX = edx;
callregs.SS = 0;
callregs.SP = 0;
callregs.DS = 0;
callregs.ES = 0;
callregs.FS = 0;
callregs.GS = 0;
callregs.IP = function;
callregs.CS = function >> 16;
status = DPMI_CallRealModeFunction( &callregs );
if ( status != DPMI_Ok )
{
return( PAS_Error );
}
return( callregs.EBX & 0xff );
}
/*---------------------------------------------------------------------
Function: PAS_SetPCMVolume
Sets the volume of digitized sound playback.
---------------------------------------------------------------------*/
int PAS_SetPCMVolume
(
int volume
)
{
int status;
volume = max( 0, volume );
volume = min( volume, 255 );
volume *= 100;
volume /= 255;
status = PAS_CallMVFunction( PAS_Func->SetMixer, volume,
OUTPUTMIXER, L_PCM );
if ( status == PAS_Error )
{
return( status );
}
status = PAS_CallMVFunction( PAS_Func->SetMixer, volume,
OUTPUTMIXER, R_PCM );
if ( status == PAS_Error )
{
return( status );
}
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_GetPCMVolume
Returns the current volume of digitized sound playback.
---------------------------------------------------------------------*/
int PAS_GetPCMVolume
(
void
)
{
int leftvolume;
int rightvolume;
int totalvolume;
if ( PAS_Func == NULL )
{
return( PAS_Error );
}
leftvolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, L_PCM );
rightvolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, R_PCM );
if ( ( leftvolume == PAS_Error ) || ( rightvolume == PAS_Error ) )
{
return( PAS_Error );
}
leftvolume &= 0xff;
rightvolume &= 0xff;
totalvolume = ( rightvolume + leftvolume ) / 2;
totalvolume *= 255;
totalvolume /= 100;
return( totalvolume );
}
/*---------------------------------------------------------------------
Function: PAS_SetFMVolume
Sets the volume of FM sound playback.
---------------------------------------------------------------------*/
void PAS_SetFMVolume
(
int volume
)
{
volume = max( 0, volume );
volume = min( volume, 255 );
volume *= 100;
volume /= 255;
if ( PAS_Func )
{
PAS_CallMVFunction( PAS_Func->SetMixer, volume, OUTPUTMIXER, L_FM );
PAS_CallMVFunction( PAS_Func->SetMixer, volume, OUTPUTMIXER, R_FM );
}
}
/*---------------------------------------------------------------------
Function: PAS_GetFMVolume
Returns the current volume of FM sound playback.
---------------------------------------------------------------------*/
int PAS_GetFMVolume
(
void
)
{
int leftvolume;
int rightvolume;
int totalvolume;
if ( PAS_Func == NULL )
{
return( 255 );
}
leftvolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, L_FM ) & 0xff;
rightvolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, R_FM ) & 0xff;
totalvolume = ( rightvolume + leftvolume ) / 2;
totalvolume *= 255;
totalvolume /= 100;
totalvolume = min( 255, totalvolume );
return( totalvolume );
}
/*---------------------------------------------------------------------
Function: PAS_GetCardInfo
Returns the maximum number of bits that can represent a sample
(8 or 16) and the number of channels (1 for mono, 2 for stereo).
---------------------------------------------------------------------*/
int PAS_GetCardInfo
(
int *MaxSampleBits,
int *MaxChannels
)
{
int status;
if ( PAS_State == NULL )
{
status = PAS_CheckForDriver();
if ( status != PAS_Ok )
{
return( status );
}
PAS_State = PAS_GetStateTable();
if ( PAS_State == NULL )
{
return( PAS_Error );
}
}
*MaxChannels = 2;
// Check board revision. Revision # 0 can't play 16-bit data.
if ( ( PAS_State->intrctlr & 0xe0 ) == 0 )
{
*MaxSampleBits = 8;
}
else
{
*MaxSampleBits = 16;
}
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_SetCallBack
Specifies the user function to call at the end of a sound transfer.
---------------------------------------------------------------------*/
void PAS_SetCallBack
(
void ( *func )( void )
)
{
PAS_CallBack = func;
}
/*---------------------------------------------------------------------
Function: PAS_FindCard
Auto-detects the port the Pro AudioSpectrum is set for.
---------------------------------------------------------------------*/
int PAS_FindCard
(
void
)
{
int status;
status = PAS_TestAddress( DEFAULT_BASE );
if ( status == 0 )
{
PAS_TranslateCode = DEFAULT_BASE;
return( PAS_Ok );
}
status = PAS_TestAddress( ALT_BASE_1 );
if ( status == 0 )
{
PAS_TranslateCode = ALT_BASE_1;
return( PAS_Ok );
}
status = PAS_TestAddress( ALT_BASE_2 );
if ( status == 0 )
{
PAS_TranslateCode = ALT_BASE_2;
return( PAS_Ok );
}
status = PAS_TestAddress( ALT_BASE_3 );
if ( status == 0 )
{
PAS_TranslateCode = ALT_BASE_3;
return( PAS_Ok );
}
PAS_SetErrorCode( PAS_CardNotFound );
return( PAS_Error );
}
/*---------------------------------------------------------------------
Function: PAS_SaveMusicVolume
Saves the user's FM mixer settings.
---------------------------------------------------------------------*/
int PAS_SaveMusicVolume
(
void
)
{
int status;
int data;
if ( !PAS_Installed )
{
status = PAS_CheckForDriver();
if ( status != PAS_Ok )
{
return( status );
}
PAS_State = PAS_GetStateTable();
if ( PAS_State == NULL )
{
return( PAS_Error );
}
PAS_Func = PAS_GetFunctionTable();
if ( PAS_Func == NULL )
{
return( PAS_Error );
}
status = PAS_GetCardSettings();
if ( status != PAS_Ok )
{
return( status );
}
status = PAS_FindCard();
if ( status != PAS_Ok )
{
return( status );
}
// Enable PAS Sound
data = PAS_State->audiofilt;
data |= PAS_AudioMuteFlag;
PAS_Write( AudioFilterControl, data );
PAS_State->audiofilt = data;
}
status = PAS_CallMVFunction( PAS_Func->GetMixer, 0, OUTPUTMIXER, L_FM );
if ( status != PAS_Error )
{
PAS_OriginalFMLeftVolume = PAS_CallMVFunction( PAS_Func->GetMixer,
0, OUTPUTMIXER, L_FM ) & 0xff;
PAS_OriginalFMRightVolume = PAS_CallMVFunction( PAS_Func->GetMixer,
0, OUTPUTMIXER, R_FM ) & 0xff;
return( PAS_Ok );
}
return( PAS_Warning );
}
/*---------------------------------------------------------------------
Function: PAS_RestoreMusicVolume
Restores the user's FM mixer settings.
---------------------------------------------------------------------*/
void PAS_RestoreMusicVolume
(
void
)
{
if ( PAS_Func )
{
PAS_CallMVFunction( PAS_Func->SetMixer, PAS_OriginalFMLeftVolume,
OUTPUTMIXER, L_FM );
PAS_CallMVFunction( PAS_Func->SetMixer, PAS_OriginalFMRightVolume,
OUTPUTMIXER, R_FM );
}
}
/*---------------------------------------------------------------------
Function: PAS_SaveState
Saves the original state of the PAS prior to use.
---------------------------------------------------------------------*/
void PAS_SaveState
(
void
)
{
PAS_OriginalState.intrctlr = PAS_State->intrctlr;
PAS_OriginalState.audiofilt = PAS_State->audiofilt;
PAS_OriginalState.tmrctlr = PAS_State->tmrctlr;
PAS_OriginalState.samplerate = PAS_State->samplerate;
PAS_OriginalState.samplecnt = PAS_State->samplecnt;
PAS_OriginalState.crosschannel = PAS_State->crosschannel;
PAS_SampleSizeConfig = PAS_Read( SampleSizeConfiguration );
}
/*---------------------------------------------------------------------
Function: PAS_RestoreState
Restores the original state of the PAS after use.
---------------------------------------------------------------------*/
void PAS_RestoreState
(
void
)
{
int LoByte;
int HiByte;
// Select the Sample Rate Timer
PAS_Write( LocalTimerControl, SelectSampleRateTimer );
PAS_State->tmrctlr = SelectSampleRateTimer;
PAS_Write( SampleRateTimer, PAS_OriginalState.samplerate );
PAS_State->samplerate = PAS_OriginalState.samplerate;
// Select the Sample Buffer Count
PAS_Write( LocalTimerControl, SelectSampleBufferCount );
PAS_State->tmrctlr = SelectSampleBufferCount;
LoByte = lobyte( PAS_OriginalState.samplecnt );
HiByte = hibyte( PAS_OriginalState.samplecnt );
PAS_Write( SampleRateTimer, LoByte );
PAS_Write( SampleRateTimer, HiByte );
PAS_State->samplecnt = PAS_OriginalState.samplecnt;
PAS_Write( CrossChannelControl, PAS_OriginalState.crosschannel );
PAS_State->crosschannel = PAS_OriginalState.crosschannel;
PAS_Write( SampleSizeConfiguration, PAS_SampleSizeConfig );
PAS_Write( InterruptControl, PAS_OriginalState.intrctlr );
PAS_State->intrctlr = PAS_OriginalState.intrctlr;
PAS_Write( AudioFilterControl, PAS_OriginalState.audiofilt );
PAS_State->audiofilt = PAS_OriginalState.audiofilt;
PAS_Write( LocalTimerControl, PAS_OriginalState.tmrctlr );
PAS_State->tmrctlr = PAS_OriginalState.tmrctlr;
}
/*---------------------------------------------------------------------
Function: PAS_LockEnd
Used for determining the length of the functions to lock in memory.
---------------------------------------------------------------------*/
static void PAS_LockEnd
(
void
)
{
}
/*---------------------------------------------------------------------
Function: allocateTimerStack
Allocate a block of memory from conventional (low) memory and return
the selector (which can go directly into a segment register) of the
memory block or 0 if an error occured.
---------------------------------------------------------------------*/
static unsigned short allocateTimerStack
(
unsigned short size
)
{
union REGS regs;
// clear all registers
memset( ®s, 0, sizeof( regs ) );
// DPMI allocate conventional memory
regs.w.ax = 0x100;
// size in paragraphs
regs.w.bx = ( size + 15 ) / 16;
int386( 0x31, ®s, ®s );
if (!regs.w.cflag)
{
// DPMI call returns selector in dx
// (ax contains real mode segment
// which is ignored here)
return( regs.w.dx );
}
// Couldn't allocate memory.
return( NULL );
}
/*---------------------------------------------------------------------
Function: deallocateTimerStack
Deallocate a block of conventional (low) memory given a selector to
it. Assumes the block was allocated with DPMI function 0x100.
---------------------------------------------------------------------*/
static void deallocateTimerStack
(
unsigned short selector
)
{
union REGS regs;
if ( selector != NULL )
{
// clear all registers
memset( ®s, 0, sizeof( regs ) );
regs.w.ax = 0x101;
regs.w.dx = selector;
int386( 0x31, ®s, ®s );
}
}
/*---------------------------------------------------------------------
Function: PAS_Init
Initializes the sound card and prepares the module to play
digitized sounds.
---------------------------------------------------------------------*/
int PAS_Init
(
void
)
{
int Interrupt;
int status;
int data;
if ( PAS_Installed )
{
return( PAS_Ok );
}
PAS_IntController1Mask = inp( 0x21 );
PAS_IntController2Mask = inp( 0xA1 );
status = PAS_CheckForDriver();
if ( status != PAS_Ok )
{
return( status );
}
PAS_State = PAS_GetStateTable();
if ( PAS_State == NULL )
{
return( PAS_Error );
}
PAS_Func = PAS_GetFunctionTable();
if ( PAS_Func == NULL )
{
return( PAS_Error );
}
status = PAS_GetCardSettings();
if ( status != PAS_Ok )
{
return( status );
}
status = PAS_FindCard();
if ( status != PAS_Ok )
{
return( status );
}
PAS_SaveState();
PAS_OriginalPCMLeftVolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, L_PCM ) & 0xff;
PAS_OriginalPCMRightVolume = PAS_CallMVFunction( PAS_Func->GetMixer, 0,
OUTPUTMIXER, R_PCM ) & 0xff;
PAS_SoundPlaying = FALSE;
PAS_SetCallBack( NULL );
PAS_DMABuffer = NULL;
status = PAS_LockMemory();
if ( status != PAS_Ok )
{
PAS_UnlockMemory();
return( status );
}
StackSelector = allocateTimerStack( kStackSize );
if ( StackSelector == NULL )
{
PAS_UnlockMemory();
PAS_SetErrorCode( PAS_OutOfMemory );
return( PAS_Error );
}
// Leave a little room at top of stack just for the hell of it...
StackPointer = kStackSize - sizeof( long );
// Install our interrupt handler
Interrupt = PAS_Interrupts[ PAS_Irq ];
PAS_OldInt = _dos_getvect( Interrupt );
if ( PAS_Irq < 8 )
{
_dos_setvect( Interrupt, PAS_ServiceInterrupt );
}
else
{
status = IRQ_SetVector( Interrupt, PAS_ServiceInterrupt );
if ( status != IRQ_Ok )
{
PAS_UnlockMemory();
deallocateTimerStack( StackSelector );
StackSelector = NULL;
PAS_SetErrorCode( PAS_UnableToSetIrq );
return( PAS_Error );
}
}
// Enable PAS Sound
data = PAS_State->audiofilt;
data |= PAS_AudioMuteFlag;
PAS_Write( AudioFilterControl, data );
PAS_State->audiofilt = data;
PAS_SetPlaybackRate( PAS_DefaultSampleRate );
PAS_SetMixMode( PAS_DefaultMixMode );
PAS_Installed = TRUE;
PAS_SetErrorCode( PAS_Ok );
return( PAS_Ok );
}
/*---------------------------------------------------------------------
Function: PAS_Shutdown
Ends transfer of sound data to the sound card and restores the
system resources used by the card.
---------------------------------------------------------------------*/
void PAS_Shutdown
(
void
)
{
int Interrupt;
if ( PAS_Installed )
{
// Halt the DMA transfer
PAS_StopPlayback();
// Restore the original interrupt
Interrupt = PAS_Interrupts[ PAS_Irq ];
if ( PAS_Irq >= 8 )
{
IRQ_RestoreVector( Interrupt );
}
_dos_setvect( Interrupt, PAS_OldInt );
PAS_SoundPlaying = FALSE;
PAS_DMABuffer = NULL;
PAS_SetCallBack( NULL );
PAS_CallMVFunction( PAS_Func->SetMixer, PAS_OriginalPCMLeftVolume,
OUTPUTMIXER, L_PCM );
PAS_CallMVFunction( PAS_Func->SetMixer, PAS_OriginalPCMRightVolume,
OUTPUTMIXER, R_PCM );
// DEBUG
// PAS_RestoreState();
PAS_UnlockMemory();
deallocateTimerStack( StackSelector );
StackSelector = NULL;
PAS_Installed = FALSE;
}
}
/*---------------------------------------------------------------------
Function: PAS_UnlockMemory
Unlocks all neccessary data.
---------------------------------------------------------------------*/
void PAS_UnlockMemory
(
void
)
{
DPMI_UnlockMemoryRegion( PAS_LockStart, PAS_LockEnd );
DPMI_Unlock( PAS_Interrupts );
DPMI_Unlock( PAS_OldInt );
DPMI_Unlock( PAS_IntController1Mask );
DPMI_Unlock( PAS_IntController2Mask );
DPMI_Unlock( PAS_Installed );
DPMI_Unlock( PAS_TranslateCode );
DPMI_Unlock( PAS_OriginalPCMLeftVolume );
DPMI_Unlock( PAS_OriginalPCMRightVolume );
DPMI_Unlock( PAS_OriginalFMLeftVolume );
DPMI_Unlock( PAS_OriginalFMRightVolume );
DPMI_Unlock( PAS_DMAChannel );
DPMI_Unlock( PAS_Irq );
DPMI_Unlock( PAS_State );
DPMI_Unlock( PAS_Func );
DPMI_Unlock( PAS_OriginalState );
DPMI_Unlock( PAS_SampleSizeConfig );
DPMI_Unlock( PAS_DMABuffer );
DPMI_Unlock( PAS_DMABufferEnd );
DPMI_Unlock( PAS_CurrentDMABuffer );
DPMI_Unlock( PAS_TotalDMABufferSize );
DPMI_Unlock( PAS_TransferLength );
DPMI_Unlock( PAS_MixMode );
DPMI_Unlock( PAS_SampleRate );
DPMI_Unlock( PAS_TimeInterval );
DPMI_Unlock( PAS_SoundPlaying );
DPMI_Unlock( PAS_CallBack );
DPMI_Unlock( PAS_ErrorCode );
DPMI_Unlock( irqstatus );
}
/*---------------------------------------------------------------------
Function: PAS_LockMemory
Locks all neccessary data.
---------------------------------------------------------------------*/
int PAS_LockMemory
(
void
)
{
int status;
status = DPMI_LockMemoryRegion( PAS_LockStart, PAS_LockEnd );
status |= DPMI_Lock( PAS_Interrupts );
status |= DPMI_Lock( PAS_OldInt );
status |= DPMI_Lock( PAS_IntController1Mask );
status |= DPMI_Lock( PAS_IntController2Mask );
status |= DPMI_Lock( PAS_Installed );
status |= DPMI_Lock( PAS_TranslateCode );
status |= DPMI_Lock( PAS_OriginalPCMLeftVolume );
status |= DPMI_Lock( PAS_OriginalPCMRightVolume );
status |= DPMI_Lock( PAS_OriginalFMLeftVolume );
status |= DPMI_Lock( PAS_OriginalFMRightVolume );
status |= DPMI_Lock( PAS_DMAChannel );
status |= DPMI_Lock( PAS_Irq );
status |= DPMI_Lock( PAS_State );
status |= DPMI_Lock( PAS_Func );
status |= DPMI_Lock( PAS_OriginalState );
status |= DPMI_Lock( PAS_SampleSizeConfig );
status |= DPMI_Lock( PAS_DMABuffer );
status |= DPMI_Lock( PAS_DMABufferEnd );
status |= DPMI_Lock( PAS_CurrentDMABuffer );
status |= DPMI_Lock( PAS_TotalDMABufferSize );
status |= DPMI_Lock( PAS_TransferLength );
status |= DPMI_Lock( PAS_MixMode );
status |= DPMI_Lock( PAS_SampleRate );
status |= DPMI_Lock( PAS_TimeInterval );
status |= DPMI_Lock( PAS_SoundPlaying );
status |= DPMI_Lock( PAS_CallBack );
status |= DPMI_Lock( PAS_ErrorCode );
status |= DPMI_Lock( irqstatus );
if ( status != DPMI_Ok )
{
PAS_UnlockMemory();
PAS_SetErrorCode( PAS_DPMI_Error );
return( PAS_Error );
}
return( PAS_Ok );
}