beep.c

isp1160_isa_evel_codeUSB主机软件

/*
**  Kenobi2          version 1.3  (Sing unit)
**
**      ** This code has been made to check/learn the 1161 functionalities ** 
**      ** Release 25-Feb-2002                                             **
**
**      OKANO, Akifumi 
**      
**		Computing Segment, Semisonductors Div, Philips Japan Ltd.
**      [e-mail]
**      [phone] 
*/

#ifndef		NoBEEP

#include	<stdio.h>
#include	<math.h>
#include	<limits.h>

#include	"dev_ep.h"
#include	"ui.h"
#include	"sing.h"
#include	"beep.h"

#define		PI				3.1415926535


unsigned long		g_beep_sample_count;
unsigned long		g_duration;
unsigned char		g_decay_sw;

double				g_freq_factor_L;
double				g_freq_factor_R;


unsigned int buffer_fill_beep_sound( unsigned char *buffer_ptr );



void beep( double frequency, double duration, unsigned char decay, unsigned char poly )
{
	device_instance		*dvi_ptr;

	if ( is_audio_active() )
		return;


	/*								*/
	/*  Finding USB audio device	*/
	/*								*/
	
	if ( NULL == (dvi_ptr		= find_class_interface( AUDIO_CLASS_INTERFACE )) )
		return ;

	g_beep_sample_count		= 0;
	g_duration				= (unsigned long)(duration * 44100);
	g_decay_sw				= decay;
	
	g_freq_factor_L			= frequency * ((2.00 * PI) / 44100.00);
	
	if ( poly == MONO )
		g_freq_factor_R			= g_freq_factor_L * 1.00;
	else
		g_freq_factor_R			= g_freq_factor_L * 1.3333333333;

	/*								*/
	/*	Initialize Audio functions	*/
	/*								*/
	
	if ( 0 != audio_initialize( dvi_ptr, NULL, buffer_fill_beep_sound ) )
		return;
		
		
	/*								*/
	/*	Start to play Audio 		*/
	/*								*/

	audio_start();
}


unsigned int buffer_fill_beep_sound( unsigned char *buffer_ptr )
{
	short				*bf;
	short				sample_L;
	short				sample_R;
	double				amp;
	unsigned int		i			= 0;

	bf		= (short *)buffer_ptr;

	if ( g_decay_sw )
	{
//		amp			= 0.10 * (1.00 - log10( 1.00 + g_beep_sample_count / (g_duration * 0.10) ));		//	log decay
		amp		    = 0.70 * ((double)(g_duration - g_beep_sample_count) / (double)g_duration);			//	linear decay
	}
	else
	{
		amp		    = 0.70;
	}
	
	amp		   *= (double)SHRT_MAX;
	
	while ( ((g_beep_sample_count + 1) < g_duration) && (i < (SINGLE_BUFFER_SIZE__SHORT >> 1)) )
	{
		sample_L			= (short)( sin( (double)g_beep_sample_count * g_freq_factor_L ) * amp);
		sample_R			= (short)( sin( (double)g_beep_sample_count * g_freq_factor_R ) * amp);
		
		*bf++	= sample_L;
		*bf++	= sample_R;
		
		g_beep_sample_count++;
		i++;
		
#if 0
		*bf++	= sample_L;
		*bf++	= sample_R;
		
		g_beep_sample_count++;
		i++;
#endif
	}
	
	return ( i << 2 );

}






















#endif