gbsnd.h

ESS3890+SL原代码（1*16内存）

/* Copyright 2001, ESS Technology, Inc.
/* SCCSID @(#)gbsnd.h	1.7 03/27/03 */

/* Based on gbsnd.h	1.10 03/14/02 */

/** VGB: portable GameBoy emulator ***************************/
/**                                                         **/
/**                         GBSND.c                         **/
/**                                                         **/
/** This file contains definitions and declarations for     **/
/** routines in GBSND.c.                                    **/
/**                                                         **/
/** Copyright (C) Marat Fayzullin 1995-2001                 **/
/**     The contents of this file are property of Marat     **/
/**     Fayzullin and should only be used as agreed with    **/
/**     him. The file is confidential. Absolutely no        **/
/**     distribution allowed.                               **/
/*************************************************************/
#ifndef GBSND_H
#define GBSND_H

#define GBSND_BASE     131072 /* Base frequency             */
#define GBSND_CHANNELS 4      /* Number of channels         */
#define RECORD_NOTES   8 
#define SND_CONSTANT 111861 /* Sound base frequency (Hz)     */
#define SND_UPDATE   60     /* Sound update frequency (Hz)   */


#ifndef BYTE_TYPE_DEFINED
#define BYTE_TYPE_DEFINED
typedef unsigned char byte;
#endif
#ifndef WORD_TYPE_DEFINED
#define WORD_TYPE_DEFINED
typedef unsigned short word;
#endif

#ifdef VGB
/** GBSND ****************************************************/
/** This data structure stores GameBoy sound chip state.    **/
/*************************************************************/
typedef struct
{
  byte *R;                      /* Current register contents from FF00h */

  /* Sound parameters */
  int Count[GBSND_CHANNELS];    /* Counter to the sound's end (ms) */
  int Length[GBSND_CHANNELS];   /* Sound length (ms) */
  int Freq[GBSND_CHANNELS];     /* Frequency (Hz) */
  int Volume[GBSND_CHANNELS];   /* Volume (0..15) */
  int ChVolume[GBSND_CHANNELS]; /* Master volume (0..14) */

  /* Volume Envelopes */
  int VCount[GBSND_CHANNELS];   /* Counter to the next step (ms) */
  int VPeriod[GBSND_CHANNELS];  /* Time between steps (ms) */
  int VDir[GBSND_CHANNELS];     /* Increment (+1) or decrement (-1) */

  /* CH1 Frequency Sweep */
  int FCount;                   /* Counter to the next step (ms) */
  int FPeriod;                  /* Time between steps (ms) */
  int FDir;                     /* Increment (+1) or decrement (-1) */
  int FNumber;                  /* Frequency number 000h-7FFh */
  int FStep;                    /* FNum[t+1]=FNum[t]+FNum[t]/(2^FStep) */

  int First;                    /* First Sound() channel to use */
  
  int rp;
  int wp;
  int freq[RECORD_NOTES][GBSND_CHANNELS];
  int volume[RECORD_NOTES][GBSND_CHANNELS];
  int SOUND_amplify;
  int lasttimer;
  int deltatime;
  int savedvol[GBSND_CHANNELS];
  int savedfreq[GBSND_CHANNELS];
  int lastvol[GBSND_CHANNELS];

} GBSND;

GBSND *SNDChip;           /* GameBoy sound chip state         */

/** ResetSND() ***********************************************/
/** Reset the sound chip and use sound channels from the    **/
/** one given in First.                                     **/
/*************************************************************/
void ResetSND(register GBSND *D,byte *Regs,int First);

/** WriteSND() ***********************************************/
/** Call this function to output a value V into the sound   **/
/** chip register A.                                        **/
/*************************************************************/
byte WriteSND(register GBSND *D,register byte A,register byte V);

/** LoopSND() ************************************************/
/** Call this function periodically to update volume        **/
/** envelopes. Use mS to pass the time since the last call  **/
/** of LoopSND() in milliseconds.                           **/
/*************************************************************/
int LoopSND(register GBSND *D,int mS);

/** SyncSND() ************************************************/
/** Flush all accumulated changes by issuing Sound() calls  **/
/** and set the synchronization on/off. The second argument **/
/** should be GBSND_SYNC/GBSND_ASYNC to set/reset sync, or  **/
/** GBSND_FLUSH to leave sync mode as it is. To emulate     **/
/** noise channel with MIDI drums, OR second argument with  **/
/** GBSND_DRUMS.                                            **/
/*************************************************************/
void SyncSND();
#endif

#ifdef INES
typedef struct
{
  /* Sound parameters */
  int  Volume[6];
  int  Freq[6];      /* Sound volumes (0-255) and frequencies (Hz) */
  int  VSweep[5];
  int  FSweep[5];    /* Volume and frequency deltas                */
  int  VCount[5];
  int  FCount[5];    /* Volume envelope and frequency counters     */
  int  VDecay[5];    /* Volume decay                               */
  byte SND[32];      /* Sound chip registers                       */

  int rp;
  int wp;
  int freq[RECORD_NOTES][GBSND_CHANNELS];
  int volume[RECORD_NOTES][GBSND_CHANNELS];
  int SOUND_amplify;
  int lasttimer;
  int deltatime;
  int motor_cnt;

  int volume_display;  /* For volume bar display */
  int volume_display_stime;
} NESSND;

#ifndef CD_GAME
NESSND  *NSNDChip;
int *P_Lengths;
int *Noise_freq;
extern int key0;

int SoundLoop(int);
int InitSound(int Rate) ;
void TrashSound(void);
#endif /*CD_GAME*/
#endif

/** TrashSound() *********************************************/
/** Shut down sound.                                        **/
/*************************************************************/


#endif /* GBSND_H */