sample2413.c

/*============================================================

  Test code for emu2413.c

    Write 2 seconds of the piano tone into temp.wav

  gcc -Wall -lm sample2413.c emu2413.c
  (The author had tried to compile on Solaris7 with gcc 2.8.1)

=============================================================*/
#include <stdio.h>
#include <time.h>
#include "emu2413.h"

/* Standard clock = MSX clock */
#define MSX_CLK 3579545

#define SAMPLERATE 44100
#define DATALENGTH (SAMPLERATE*2) 

static void WORD(char *buf, uint32 data){

  buf[0] = data & 0xff ;
  buf[1] = (data & 0xff00) >> 8 ;

}

static void DWORD(char *buf, uint32 data){

  buf[0] = data & 0xff ;
  buf[1] = (data & 0xff00) >> 8 ;
  buf[2] = (data & 0xff0000) >> 16 ;
  buf[3] = (data & 0xff000000) >> 24 ;

}

static void chunkID(char *buf, char id[4]){

  buf[0] = id[0] ;
  buf[1] = id[1] ;
  buf[2] = id[2] ;
  buf[3] = id[3] ;

}

int main(void){

  static char wave[DATALENGTH*2] ;
  char filename[16] = "temp.wav" ;
  char header[46] ;
  int i ;
  clock_t start,finish ;

  FILE *fp ;
  OPLL *opll ;

  /* Create WAVE header */
  chunkID(header,"RIFF") ;
  DWORD(header+4,DATALENGTH*2+36) ;
  chunkID(header+8,"WAVE") ;
  chunkID(header+12,"fmt ") ;
  DWORD(header+16,16) ;
  WORD(header+20,1) ;                   /* WAVE_FORMAT_PCM */
  WORD(header+22,1) ;                   /* channel 1=mono,2=stereo */
  DWORD(header+24,SAMPLERATE) ;         /* samplesPerSec */
  DWORD(header+28,2*SAMPLERATE) ;       /* bytesPerSec */
  WORD(header+32,2) ;                   /* blockSize */
  WORD(header+34,16) ;                  /* bitsPerSample */
  chunkID(header+36,"data") ;
  DWORD(header+40,2*DATALENGTH) ;

  OPLL_init(MSX_CLK,SAMPLERATE) ;
  opll = OPLL_new() ;
  OPLL_reset(opll) ;
  OPLL_reset_patch(opll,0) ;            /* if use default voice data. */ 

  OPLL_writeReg(opll,0x30,0x30) ;   /* select PIANO Voice to ch1. */ 
  OPLL_writeReg(opll,0x10,80) ;     /* set F-Number(L). */
  OPLL_writeReg(opll,0x20,0x15) ;   /* set BLK & F-Number(H) and keyon. */

  start = clock() ;

  for(i=0;i<DATALENGTH;i++)
    WORD(wave+i*2,OPLL_calc(opll));

  finish = clock() ;

  OPLL_delete(opll) ;
  OPLL_close() ;

  printf("It has been %f sec to calc %d waves.\n",
	 (double)(finish-start)/CLOCKS_PER_SEC, DATALENGTH) ;
  printf("%f times faster than real YM2413.\n",
	 ((double)DATALENGTH/SAMPLERATE)/((double)(finish-start)/CLOCKS_PER_SEC)) ;

  fp = fopen(filename,"wb") ;
  
  if(fp == NULL) return 1 ;

  fwrite(header,46,1,fp) ;
  fwrite(wave,DATALENGTH,2,fp) ;
  
  fclose(fp) ;

  printf("Wrote : %s\n",filename) ;

  return 0 ;
}