playmix.cpp

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/****************************************************************************
*                                                                           *
*  (C) Copyright Creative Technology Ltd. 1994-1996. All rights reserved.   *
*                                                                           *
*  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY    *
*  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE      *
*  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR    *
*  PURPOSE.                                                                 *
*                                                                           *
* You have a royalty-free right to use, modify, reproduce and               *
* distribute the Sample Files (and/or any modified version) in              *
* any way you find useful, provided that you agree that                     *
* Creative has no warranty obligations or liability for any Sample Files.   *
*                                                                           *
****************************************************************************/

/*
 * Program to demonstrate mixing of two VOC files, pitch shifting one of them,
 * and playing them using low-level programming.
 *
 * D. Kaden 8/4/93
 *
 * Modified 1/31/94
 * Got rid of PLAYMIX1 and PLAYMIX2, made PLAYMIX.  Made it take file names
 * from the command line.
 *
 */



#define AUTOINIT      /* Define this for auto-initialized mode (no clicks).
                       * Undefine it for non-auto-init mode, but it will
                       * click slightly.  Auto-init is only available on
                       * cards with DSP versions of 2 or above.
                       */



#include <stdio.h>
#include <dos.h>
#include <stdlib.h>
#include <conio.h>
#include <dir.h>
#include <string.h>
#include "mix.h"


#define SPACEKEY ' '
#define ESC 27
#define LEFTKEY 75        /* really 0, 75 */
#define RIGHTKEY 77
#define F1KEY 59
#define F2KEY 60
#define F3KEY 61
#define F4KEY 62

#define dspReady 0xAA     /* byte returned by DSP when ready after reset */


/***
 *** WARNING:  THESE CONSTANTS DEFINE HOW THE PROGRAM ASSUMES THE BOARD TO
 *** BE CONFIGURED.  MAKE SURE THESE MATCH YOUR BOARD BEFORE YOU RUN THIS
 *** PROGRAM.  DON'T USE IRQ 10, THOUGH, BECAUSE THIS PROGRAM ISN'T DESIGNED
 *** FOR IT (it uses the other 8259 PIC).
 ***/

#define SBADDR     0x220        /* Sound Blaster base port address */
#define SBIRQNUM   5            /* Sound Blaster IRQ number */
#define SBDMACHAN  1            /* Sound Blaster DMA channel */


#define IRQ (SBIRQNUM+8)        /* interrupt number corresponding to IRQ number */
#define IRQmask (1 << SBIRQNUM) /* interrupt mask corresponding to IRQ number */


/* port addresses for Sound Blaster */
#define dspaddrWrBuf     (SBADDR+0xC)    /* DSP Write Buffer address */
#define dspaddrReadData  (SBADDR+0xA)    /* DSP Read Data address */
#define dspaddrDataAvail (SBADDR+0xE)    /* DSP Data Available address */
#define mixeraddr        (SBADDR+0x4)    /* mixer address (register select) port */
#define mixerdata        (SBADDR+0x5)    /* mixer data port */
#define dspaddrReset     (SBADDR+0x6)    /* dsp reset port address */


/* port addresses for 8237 DMA controller and its page registers */
#define DMACMaskReg 0xA
#define DMACModeReg 0xB
#define DMACFFReg   0xC
#define DMA1PAGE    0x83
#define DMA1ADDR    0x2
#define DMA1COUNT   0x3
#define DMA3PAGE    0x82
#define DMA3ADDR    0x6
#define DMA3COUNT   0x7


#if SBDMACHAN==1
   #define DMAPAGE  DMA1PAGE
   #define DMAADDR  DMA1ADDR
   #define DMACOUNT DMA1COUNT
#elif SBDMACHAN==3
   #define DMAPAGE  DMA3PAGE
   #define DMAADDR  DMA3ADDR
   #define DMACOUNT DMA3COUNT
#else
   ERROR: No constants defined for DMA channel.
#endif


/* constants for 8250 Peripheral Interrupt Controller */
#define PICMODE     0x20
#define PICMASK     0x21
#define PICEOI      0x20


/* some Sound Blaster commands */
#define dspcmdDirect8DAC   0x10    /* DSP Direct 8-bit DAC command */
#define dspcmdDMADAC       0x14    /* DSP 8-bit DAC DMA transfer */
#define dspcmdDirectADC    0x20    /* DSP Direct ADC command */
#define dspcmdDMAADC       0x24    /* DSP 8-bit ADC DMA transfer */
#define dspcmdTimeConst    0x40    /* set time constant for DMA transfer */
#define dspcmdBlockSize    0x48    /* DMA transfer block size */
#define dspcmdHaltDMA      0xD0    /* stop DMA */
#define dspcmdContDMA      0xD4    /* continue DMA */
#define dspcmdSpeakerOn    0xD1    /* turn speaker on */
#define dspcmdSpeakerOff   0xD3    /* turn speaker off */
#define dspcmdSpeakerStat  0xD8    /* get speaker status */

#define dspcmdAUTODMADAC   0x1C    /* DSP 8-bit ADC Auto-init DMA transfer */
#define dspcmdAUTODMAADC   0x2C    /* DSP 8-bit ADC Auto-init DMA transfer */
#define dspcmdHaltAuto     0xDA    /* halt auto-init DMA transfer */


/* Sound Blaster mixer registers */
#define MASTERVOL 0x22
#define VOCVOL    0x04
#define FMVOL     0x26
#define CDVOL     0x28
#define MICVOL    0x0A
#define ADCSELECT 0x0C



#define BUFSIZE 1024*1

unsigned char buf0[BUFSIZE], buf1[BUFSIZE];


unsigned int page0, page1, offset0, offset1, count=BUFSIZE-1, outtc=166 /* 11K */;

int BusyBuf, BufToFill;

VOCfile v1,v2;

char filename1[MAXPATH], filename2[MAXPATH];


boolean v2pitchshift=false;
boolean v1repeat=true;
boolean v2repeat=true;
unsigned int v2skip=20;



void dspout(unsigned int val)
/* Outputs a byte to the dsp.  This polls the write buffer status bit, waits
 * for it to be 0, then outputs the value to the write buffer.
 * The C equivalent code is:
 *    while (inp(dspaddrWrBuf) & 0x80)
 *        ;
 *    outp(dspaddrWrBuf,val);
 */
{
   asm {
      mov dx,dspaddrWrBuf
   }
   test:
   asm {
      in al,dx
      or al,al
      js test
      mov al,byte ptr val
      out dx,al
   }
}


void dspin(unsigned int *val)
/* Read a value from the dsp.  Poll the Data Available bit until it is 1,
 * then read the value from the read data port.
 */
{
   while (!(inp(dspaddrDataAvail) & 0x80)) {
      ;
   }
   *val=inp(dspaddrReadData);
}



void SegToPhys(unsigned char far *ptr, unsigned long size, unsigned long *physaddr, unsigned long *endaddr)
/* Converts a segmented address to a physical memory address.  Also gives
 * the end address ('size' bytes past ptr).
 */
{
   *physaddr=(unsigned long)(((unsigned long)FP_SEG(ptr) << 4) + FP_OFF(ptr));
   *endaddr = *physaddr+size-1;
}



unsigned int PhysToPage(unsigned long physaddr, unsigned long endaddr, unsigned int *page, unsigned int *offset)
/* Converts a physical memory address to a page/offset type of address for
 * DMA (NOT the same as a segmented address).  It returns the number of bytes
 * between physaddr and endaddr (the DMA buffer) that are in the DMA page.
 * If the return value is less than the buffer size (endaddr-physaddr+1),
 * the DMA buffer is crossing a page boundary and must be discarded.  In that
 * case, allocate some more memory and try again.
 */
{
   unsigned int remaining;
   *page=physaddr >> 16;
   *offset=physaddr & 0xFFFF;

   remaining=0xFFFF - *offset + 1;   /* bytes remaining in page */
   if (remaining>endaddr-physaddr)   /* if more bytes left in page than in buffer */
      return endaddr-physaddr+1;     /* return number of bytes in buffer */
   else return remaining;            /* else return number of bytes left in page */
}




void SetupOutputDMA(unsigned int page, unsigned int ofs, int count,
 unsigned char tc)
/* This programs the Sound Blaster board and the DMA controller to play
 * from a buffer.
 *
 */
{
/**** There MUST be parens around the values to be output, or the compiler
 **** will convert them to unsigned chars BEFORE it does the operations
 **** on them.
 ****/
#ifdef AUTOINIT
  /* In this mode, the DMAC and DSP are only programmed once.  The DSP is
   * programmed for a block size half of what the DMAC is programmed for,
   * so interrupts are generated every half-buffer.  In this program, buf0
   * and buf1 are both half buffers.  The DMAC will be programmed to trans-
   * fer 2*BUFSIZE, while the DSP is programmed for just BUFSIZE.
   */
   outp(DMACMaskReg,4 | SBDMACHAN);     /* mask off dma channel */
   outp(DMACFFReg,0);                   /* clear flip-flop */
/* This next value to DMAC is different between auto-init and non-auto-init.
 * (0x58 vs. 0x48) */
   outp(DMACModeReg,0x58 | SBDMACHAN);  /* set mode for DAC, channel 1 */
   outp(DMAADDR,(ofs & 0xFF));          /* low byte base addr */
   outp(DMAADDR,(ofs >> 8));            /* high byte base addr */
   outp(DMAPAGE,page);                  /* physical page number */
   outp(DMACOUNT,((count-1) & 0xFF));   /* count low byte (ENTIRE buffer) */
   outp(DMACOUNT,((count-1) >> 8));     /* count high byte */
   outp(DMACMaskReg, SBDMACHAN);        /* enable dma channel 1 */

   dspout(dspcmdTimeConst);    /* time constant command */
   dspout(tc);                 /* the time constant (for sample rate) */
   dspout(dspcmdBlockSize);    /* set block size= HALF DMA buffer size */
   dspout((count/2-1) & 0xFF);
   dspout((count/2-1) >> 8);
   dspout(dspcmdAUTODMADAC);   /* program dsp for auto-init dma mode dac */
#else
   outp(DMACMaskReg,4 | SBDMACHAN);     /* mask off dma channel */
   outp(DMACFFReg,0);                   /* clear flip-flop */
   outp(DMACModeReg,0x48 | SBDMACHAN);  /* set mode for DAC, channel 1 */
   outp(DMAADDR,(ofs & 0xFF));          /* low byte base addr */
   outp(DMAADDR,(ofs >> 8));            /* high byte base addr */
   outp(DMAPAGE,page);                  /* physical page number */
   outp(DMACOUNT,(count & 0xFF));       /* count low byte */
   outp(DMACOUNT,(count >> 8));         /* count high byte */
   outp(DMACMaskReg, SBDMACHAN);        /* enable dma channel 1 */

   dspout(dspcmdTimeConst);    /* time constant command */
   dspout(tc);                 /* the time constant (for sample rate) */