bryan wade / Mbed 2 deprecated usb_sound_effects

Streams USB audio with sound effects applied. Sound effect selected by joystick and intensity altered by tilting the mbed. Output to the mbed-application-board phono jack.

Dependencies:   C12832_lcd MMA7660 USBDevice mbed

/media/uploads/bw/img_1293.jpg 

/* Uses the mbed LPC1768 and mbed-application-board to create a USB audio device
 * that streams audio from a host computer to headphones or powered speakers. 
 * A couple different sound effects can be applied to the stream in real-time,
 * and tilting the mbed alters intensity of the effect.
 *
 *                                               ECHO
 *       The joystick selects )                   |
 *       one of three effect  )       STRAIGHT -  o  - STRAIGHT
 *       modes.               )                   |
 *                                              REVERB   
 * 
 *
 *
 *                                               \\           ||    
 *       Tilting the mbed     )      ======       \\          ||
 *       determines intensity )                    \\         ||
 *       of the effect.       )
 *                                     0%         50%         100%  
 *
 * The LCD display shows the current effect mode, intesity and buffer level.
*/

buffer.h

Committer:
bw
Date:
2014-03-27
Revision:
2:9429f84ea165
Parent:
0:bbf6cf0eab95

File content as of revision 2:9429f84ea165:

/*******************************************************************************
 * Implements FIFO buffer for glitch-free audio playback.
 * Bryan Wade
 * 27 MAR 2014
 ******************************************************************************/
#ifndef BUFFER_H
#define BUFFER_H

#include <stdint.h>
#include <stdlib.h>

typedef struct buffer_t buffer_t; // Opaque type declaration.

// Get a ptr to a new buffer.
buffer_t *Buffer_Create(void *ram, size_t size);

// Read one sample from buffer.
bool Buffer_Read(buffer_t *buffer, int16_t *pDataOut);

// Write one sample to buffer.
void Buffer_Write(buffer_t *buffer, int16_t DataIn);

// Write a block of data to buffer.
void Buffer_WriteBlock(buffer_t *buffer, const int16_t *pDataIn, uint32_t length);

// Get the current number of samples buffered.
int32_t Buffer_GetLevel(buffer_t *buffer);

#endif