dxx-rebirth/arch/dos/mm_snd/drv_sb.c
2006-03-20 17:12:09 +00:00

519 lines
8.8 KiB
C
Executable file

/*
Name:
DRV_SB.C
Description:
Mikmod driver for output on Creative Labs Soundblasters & compatibles
(through DSP)
Portability:
MSDOS: BC(y) Watcom(y) DJGPP(y)
Win95: n
Os2: n
Linux: n
(y) - yes
(n) - no (not possible or not useful)
(?) - may be possible, but not tested
*/
#include <stdio.h>
#include <stdlib.h>
#include <dos.h>
//#include <malloc.h>
//#include <conio.h>
#include <string.h>
//#ifndef __DJGPP__
//#include <mem.h>
//#endif
#include "mikmod.h"
#include "mdma.h"
#include "mirq.h"
/***************************************************************************
>>>>>>>>>>>>>>>>>>>>>>>>> Lowlevel SB stuff <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
***************************************************************************/
static UWORD sb_port; /* sb base port */
/*
Define some important SB i/o ports:
*/
#define MIXER_ADDRESS (sb_port+0x4)
#define MIXER_DATA (sb_port+0x5)
#define DSP_RESET (sb_port+0x6)
#define DSP_READ_DATA (sb_port+0xa)
#define DSP_WRITE_DATA (sb_port+0xc)
#define DSP_WRITE_STATUS (sb_port+0xc)
#define DSP_DATA_AVAIL (sb_port+0xe)
static void SB_MixerStereo(void)
/*
Enables stereo output for DSP versions 3.00 >= ver < 4.00
*/
{
outportb(MIXER_ADDRESS,0xe);
outportb(MIXER_DATA,inportb(MIXER_DATA)|2);
}
static void SB_MixerMono(void)
/*
Disables stereo output for DSP versions 3.00 >= ver < 4.00
*/
{
outportb(MIXER_ADDRESS,0xe);
outportb(MIXER_DATA,inportb(MIXER_DATA)&0xfd);
}
static BOOL SB_WaitDSPWrite(void)
/*
Waits until the DSP is ready to be written to.
returns FALSE on timeout
*/
{
UWORD timeout=32767;
while(timeout--){
if(!(inportb(DSP_WRITE_STATUS)&0x80)) return 1;
}
return 0;
}
static BOOL SB_WaitDSPRead(void)
/*
Waits until the DSP is ready to read from.
returns FALSE on timeout
*/
{
UWORD timeout=32767;
while(timeout--){
if(inportb(DSP_DATA_AVAIL)&0x80) return 1;
}
return 0;
}
static BOOL SB_WriteDSP(UBYTE data)
/*
Writes byte 'data' to the DSP.
returns FALSE on timeout.
*/
{
if(!SB_WaitDSPWrite()) return 0;
outportb(DSP_WRITE_DATA,data);
return 1;
}
static UWORD SB_ReadDSP(void)
/*
Reads a byte from the DSP.
returns 0xffff on timeout.
*/
{
if(!SB_WaitDSPRead()) return 0xffff;
return(inportb(DSP_READ_DATA));
}
static void SB_SpeakerOn(void)
/*
Enables DAC speaker output.
*/
{
SB_WriteDSP(0xd1);
}
static void SB_SpeakerOff(void)
/*
Disables DAC speaker output
*/
{
SB_WriteDSP(0xd3);
}
static void SB_ResetDSP(void)
/*
Resets the DSP.
*/
{
int t;
/* reset the DSP by sending 1, (delay), then 0 */
outportb(DSP_RESET,1);
for(t=0;t<8;t++) inportb(DSP_RESET);
outportb(DSP_RESET,0);
}
static BOOL SB_Ping(void)
/*
Checks if a SB is present at the current baseport by
resetting the DSP and checking if it returned the value 0xaa.
returns: TRUE => SB is present
FALSE => No SB detected
*/
{
SB_ResetDSP();
return(SB_ReadDSP()==0xaa);
}
static UWORD SB_GetDSPVersion(void)
/*
Gets SB-dsp version. returns 0xffff if dsp didn't respond.
*/
{
UWORD hi,lo;
if(!SB_WriteDSP(0xe1)) return 0xffff;
hi=SB_ReadDSP();
lo=SB_ReadDSP();
return((hi<<8)|lo);
}
/***************************************************************************
>>>>>>>>>>>>>>>>>>>>>>>>> The actual SB driver <<<<<<<<<<<<<<<<<<<<<<<<<<<<<
***************************************************************************/
static DMAMEM *SB_DMAMEM;
static char *SB_DMABUF;
static UBYTE SB_TIMECONSTANT;
static UWORD sb_int; /* interrupt vector that belongs to sb_irq */
static UWORD sb_ver; /* DSP version number */
static UBYTE sb_irq; /* sb irq */
static UBYTE sb_lodma; /* 8 bit dma channel (1.0/2.0/pro) */
static UBYTE sb_hidma; /* 16 bit dma channel (16/16asp) */
static UBYTE sb_dma; /* current dma channel */
static BOOL SB_IsThere(void)
{
char *envptr,c;
static char *endptr;
sb_port =0xffff;
sb_irq =0xff;
sb_lodma=0xff;
sb_hidma=0xff;
if((envptr=getenv("BLASTER"))==NULL) return 0;
while(1){
/* skip whitespace */
do c=*(envptr++); while(c==' ' || c=='\t');
/* reached end of string? -> exit */
if(c==0) break;
switch(c){
case 'a':
case 'A':
sb_port=strtol(envptr,&endptr,16);
break;
case 'i':
case 'I':
sb_irq=strtol(envptr,&endptr,10);
//added on 11/5/98 by Victor Rachels to hardwire 2->9
if(sb_irq==0x02)
sb_irq=0x09;
//end this section addition - VR
break;
case 'd':
case 'D':
sb_lodma=strtol(envptr,&endptr,10);
break;
case 'h':
case 'H':
sb_hidma=strtol(envptr,&endptr,10);
break;
default:
strtol(envptr,&endptr,16);
break;
}
envptr=endptr;
}
if(sb_port==0xffff || sb_irq==0xff || sb_lodma==0xff) return 0;
/* determine interrupt vector */
sb_int = (sb_irq>7) ? sb_irq+104 : sb_irq+8;
if(!SB_Ping()) return 0;
/* get dsp version. */
if((sb_ver=SB_GetDSPVersion())==0xffff) return 0;
return 1;
}
static void interrupt newhandler(MIRQARGS)
{
if(sb_ver<0x200){
SB_WriteDSP(0x14);
SB_WriteDSP(0xff);
SB_WriteDSP(0xfe);
}
if(md_mode & DMODE_16BITS)
inportb(sb_port+0xf);
else
inportb(DSP_DATA_AVAIL);
MIrq_EOI(sb_irq);
}
static PVI oldhandler;
static BOOL SB_Init(void)
{
ULONG t;
if(!SB_IsThere()){
myerr="No such hardware detected, check your 'BLASTER' env. variable";
return 0;
}
/* printf("SB version %x\n",sb_ver); */
/* if(sb_ver>0x200) sb_ver=0x200; */
if(sb_ver>=0x400 && sb_hidma==0xff){
myerr="High-dma setting in 'BLASTER' variable is required for SB-16";
return 0;
}
if(sb_ver<0x400 && md_mode&DMODE_16BITS){
/* DSP versions below 4.00 can't do 16 bit sound. */
md_mode&=~DMODE_16BITS;
}
if(sb_ver<0x300 && md_mode&DMODE_STEREO){
/* DSP versions below 3.00 can't do stereo sound. */
md_mode&=~DMODE_STEREO;
}
/* Use low dma channel for 8 bit, high dma for 16 bit */
sb_dma=(md_mode & DMODE_16BITS) ? sb_hidma : sb_lodma;
if(sb_ver<0x400){
t=md_mixfreq;
if(md_mode & DMODE_STEREO) t<<=1;
SB_TIMECONSTANT=256-(1000000L/t);
if(sb_ver<0x201){
if(SB_TIMECONSTANT>210) SB_TIMECONSTANT=210;
}
else{
if(SB_TIMECONSTANT>233) SB_TIMECONSTANT=233;
}
md_mixfreq=1000000L/(256-SB_TIMECONSTANT);
if(md_mode & DMODE_STEREO) md_mixfreq>>=1;
}
if(!VC_Init()) return 0;
SB_DMAMEM=MDma_AllocMem(md_dmabufsize);
if(SB_DMAMEM==NULL){
VC_Exit();
myerr="Couldn't allocate page-contiguous dma-buffer";
return 0;
}
SB_DMABUF=(char *)MDma_GetPtr(SB_DMAMEM);
oldhandler=MIrq_SetHandler(sb_irq,newhandler);
return 1;
}
static void SB_Exit(void)
{
MIrq_SetHandler(sb_irq,oldhandler);
MDma_FreeMem(SB_DMAMEM);
VC_Exit();
}
static UWORD last=0;
static UWORD curr=0;
static void SB_Update(void)
{
UWORD todo,index;
curr=(md_dmabufsize-MDma_Todo(sb_dma))&0xfffc;
if(curr==last) return;
if(curr>last){
todo=curr-last; index=last;
last+=VC_WriteBytes(&SB_DMABUF[index],todo);
MDma_Commit(SB_DMAMEM,index,todo);
if(last>=md_dmabufsize) last=0;
}
else{
todo=md_dmabufsize-last;
VC_WriteBytes(&SB_DMABUF[last],todo);
MDma_Commit(SB_DMAMEM,last,todo);
last=VC_WriteBytes(SB_DMABUF,curr);
MDma_Commit(SB_DMAMEM,0,curr);
}
}
static void SB_PlayStart(void)
{
VC_PlayStart();
MIrq_OnOff(sb_irq,1);
if(sb_ver>=0x300 && sb_ver<0x400){
if(md_mode & DMODE_STEREO){
SB_MixerStereo();
}
else{
SB_MixerMono();
}
}
/* clear the dma buffer to zero (16 bits
signed ) or 0x80 (8 bits unsigned) */
if(md_mode & DMODE_16BITS)
memset(SB_DMABUF,0,md_dmabufsize);
else
memset(SB_DMABUF,0x80,md_dmabufsize);
MDma_Commit(SB_DMAMEM,0,md_dmabufsize);
if(!MDma_Start(sb_dma,SB_DMAMEM,md_dmabufsize,INDEF_WRITE)){
return;
}
if(sb_ver<0x400){
SB_SpeakerOn();
SB_WriteDSP(0x40);
SB_WriteDSP(SB_TIMECONSTANT);
if(sb_ver<0x200){
SB_WriteDSP(0x14);
SB_WriteDSP(0xff);
SB_WriteDSP(0xfe);
}
else if(sb_ver==0x200){
SB_WriteDSP(0x48);
SB_WriteDSP(0xff);
SB_WriteDSP(0xfe);
SB_WriteDSP(0x1c);
}
else{
SB_WriteDSP(0x48);
SB_WriteDSP(0xff);
SB_WriteDSP(0xfe);
SB_WriteDSP(0x90);
}
}
else{
SB_WriteDSP(0x41);
SB_WriteDSP(md_mixfreq>>8);
SB_WriteDSP(md_mixfreq&0xff);
if(md_mode & DMODE_16BITS){
SB_WriteDSP(0xb6);
SB_WriteDSP((md_mode & DMODE_STEREO) ? 0x30 : 0x10);
}
else{
SB_WriteDSP(0xc6);
SB_WriteDSP((md_mode & DMODE_STEREO) ? 0x20 : 0x00);
}
SB_WriteDSP(0xff);
SB_WriteDSP(0xef);
}
}
static void SB_PlayStop(void)
{
VC_PlayStop();
SB_SpeakerOff();
SB_ResetDSP();
SB_ResetDSP();
MDma_Stop(sb_dma);
MIrq_OnOff(sb_irq,0);
}
MDRIVER drv_sb={
NULL,
"Soundblaster & compatibles",
"MikMod Soundblaster Driver v2.1 for 1.0 / 2.0 / Pro / 16",
SB_IsThere,
VC_SampleLoad,
VC_SampleUnload,
SB_Init,
SB_Exit,
SB_PlayStart,
SB_PlayStop,
SB_Update,
VC_VoiceSetVolume,
VC_VoiceSetFrequency,
VC_VoiceSetPanning,
VC_VoicePlay
};