wmwavegen.h

pxa270平台 windows mobile 5.2 wm9713 触摸屏+音频驱动

/*-----------------------------------------------------------------------------
 * Copyright (c) Wolfson Microelectronics plc.  All rights reserved.
 *
 * This software as well as any related documentation is furnished under 
 * license and may only be used or copied in accordance with the terms of the 
 * license. The information in this file is furnished for informational use 
 * only, is subject to change without notice, and should not be construed as 
 * a commitment by Wolfson Microelectronics plc. Wolfson Microelectronics plc
 * assumes no responsibility or liability for any errors or inaccuracies that
 * may appear in this document or any software that may be provided in
 * association with this document. 
 *
 * Except as permitted by such license, no part of this document may be 
 * reproduced, stored in a retrieval system, or transmitted in any form or by 
 * any means without the express written consent of Wolfson Microelectronics plc. 
 *
 * $Id: WMWaveGen.h 4452 2007-05-29 09:40:15Z fb $
 *
 * Functions for generating different sound waveforms.
 *
 * Warning:
 *  This driver is specifically written for Wolfson Codecs. It is not a 
 *  general CODEC device driver.
 *
 * -----------------------------------------------------------------------------*/
#ifndef __WMWAVEGEN_H__
#define __WMWAVEGEN_H__

/*
 * Include files
 */
#include "WMConfig.h"
#include "WMPlatformDefs.h"     /* for WM_AUDIO_SAMPLE */

/*
 * Definitions
 */

/*!
 * WM_WAVEGEN_FORMAT specifies what sort of data to generate.
 * 
 * Stereo data has the right channel in the upper 16 bits and the left channel
 * in the lower 16 bits of the 32-bit word.
 */
typedef enum tagWM_WAVEGEN_FORMAT
{
    WM_WAVEGEN_CONTIGUOUS_WIDE,	/*< samples butting up against each other on a 32 bit wide DMA */
    WM_WAVEGEN_CONTIGUOUS,		/*< samples butting up against each other */
    WM_WAVEGEN_MONO,			/*< single-sample mono data */
    WM_WAVEGEN_LEFT,			/*< stereo data in the left channel of each sample */
    WM_WAVEGEN_RIGHT,			/*< stereo data in the right channel of each sample */
    WM_WAVEGEN_STEREO			/*< stereo data duplicated in both channels of each sample */
} WM_WAVEGEN_FORMAT;

/*
 * A restart context for the wave generation, allowing the generation to
 * continue smoothly across multiple calls.
 */
typedef struct 
{
    int quot;
    int rem;
} WM_WAVEGEN_CTX;

/* A constant to initialise the wave generation to the start of the wave. */
#define WM_START_OF_WAVE    { 0 }

/*
 * Function prototypes
 */
#ifdef __cplusplus
extern "C" {
#endif


/*-----------------------------------------------------------------------------
 * Function:    WMGenerateSineWave
 *
 * Generates a sine wave of the given frequency.
 *
 * Parameters:
 *		buffer      buffer to receive samples
 *      nSamples    number of samples to generate (mono or stereo,
 *                   according to 'format')
 *      sampleRate  output sample rate (e.g. 44100)
 *      frequency   frequency to generate
 *      amplitude   peak amplitude to generate (0 to 32768)
 *      format      what the resulting data should look like.  One of the
 *                  WM_WAVEGEN_FORMAT constants.
 *      pRestart    pointer to a restart context - position after previous call.
 *                  Used to restart the wave where the previous call left off.
 *                  Updated to the start position for the next call.
 *                  Can be NULL - in this case will always start at the start of
 *                  the wave.
 *
 * Returns:     void
 *---------------------------------------------------------------------------*/
void WMGenerateSineWave(WM_AUDIO_STEREO_SAMPLE   *buffer,
                        int               nSamples,
                        int               sampleRate,
                        unsigned short    frequency,
                        unsigned short    amplitude,
                        WM_WAVEGEN_FORMAT format,
                        WM_WAVEGEN_CTX    *pRestart
                        );

/*-----------------------------------------------------------------------------
 * Function:    WMGenerateSquareWave
 *
 * Generates as close an approximation as possible to a square wave of the
 * given frequency.
 *
 * Parameters:
 *		buffer      buffer to receive samples
 *      nSamples    number of samples to generate (mono or stereo,
 *                   according to 'format')
 *      sampleRate  output sample rate (e.g. 44100)
 *      frequency   frequency to generate
 *      amplitude   peak amplitude to generate (0 to 32768)
 *      format      what the resulting data should look like.  One of the
 *                  WM_WAVEGEN_FORMAT constants.
 *      pRestart    pointer to a restart context - position after previous call.
 *                  Used to restart the wave where the previous call left off.
 *                  Updated to the start position for the next call.
 *                  Can be NULL - in this case will always start at the start of
 *                  the wave.
 *
 * Returns:     void
 *---------------------------------------------------------------------------*/
void WMGenerateSquareWave(WM_AUDIO_STEREO_SAMPLE   *buffer,
                          int               nSamples,
                          int               sampleRate,
                          unsigned short    frequency,
                          unsigned short    amplitude,
                          WM_WAVEGEN_FORMAT format,
                          WM_WAVEGEN_CTX    *pRestart
                          );


#ifdef __cplusplus
}   /* extern "C" */
#endif

#endif	/* __WMWAVEGEN_H__ */
/*------------------------------ END OF FILE ---------------------------------*/