AudioOutput.c File Reference

#include "AudioOutput.h"

Go to the source code of this file.

Data Structures
struct	I2S_RATE_CONFIG

Macros
#define	AUDIO_MAX_SAMPLE_FREQ   48000
#define	AUDIO_SPEEP_UP_TRIGGER   (audio_buffer_size*5/8)
#define	AUDIO_NORMAL_SPEED_TRIGGER   (audio_buffer_size*3/8)
#define	AUDIO_MAX_PC   10

Functions
PRAGMA_ALIGN_4 uint8_t audio_buffer[2048 *2]	ATTR_ALIGNED (4)
Status	I2S_RateFind (LPC_I2S_T *I2Sx, Chip_I2S_Audio_Format_T *audio_format, I2S_RATE_CONFIG *I2S_Config)
void	Audio_Reset_Data_Buffer (void)
uint32_t	Audio_Get_ISO_Buffer_Address (uint32_t last_packet_size)
void	Audio_Init (uint32_t samplefreq)
void	Audio_DeInit (void)
void	I2S0_IRQHandler (void)
uint32_t	CALLBACK_HAL_GetISOBufferAddress (const uint32_t EPNum, uint32_t *last_packet_size)
int	main (void)
	Main program body.
void	SetupHardware (void)
	Hardware setup event callback function.
void	EVENT_USB_Device_Connect (void)
	USB Device connect event callback.
void	EVENT_USB_Device_Disconnect (void)
	USB Device disconnect event callback.
void	EVENT_USB_Device_ConfigurationChanged (void)
	USB Device configuration change event callback.
void	EVENT_USB_Device_ControlRequest (void)
	USB Device control request receive event callback.
void	EVENT_Audio_Device_StreamStartStop (USB_ClassInfo_Audio_Device_t *const AudioInterfaceInfo)
	Audio class driver event for an Audio Stream start/stop change. This event fires each time the device receives a stream enable or disable control request from the host, to start and stop the audio stream. The current state of the stream can be determined by the State.InterfaceEnabled value inside the Audio interface structure passed as a parameter.
bool	CALLBACK_Audio_Device_GetSetEndpointProperty (USB_ClassInfo_Audio_Device_t *const AudioInterfaceInfo, const uint8_t EndpointProperty, const uint8_t EndpointAddress, const uint8_t EndpointControl, uint16_t *const DataLength, uint8_t *Data)

Variables
USB_ClassInfo_Audio_Device_t	Speaker_Audio_Interface
uint32_t	CurrentAudioSampleFrequency = AUDIO_MAX_SAMPLE_FREQ
uint32_t	audio_buffer_size = 0
uint32_t	audio_buffer_rd_index = 0
uint32_t	audio_buffer_wr_index = 0
uint32_t	audio_buffer_count = 0
static uint32_t	I2S_SpeedConfig_index

Macro Definition Documentation

#define AUDIO_MAX_PC   10

Audio APIAudio max packet count.

Definition at line 64 of file AudioOutput.c.

#define AUDIO_MAX_SAMPLE_FREQ   48000

Max Sample Frequency.

Definition at line 52 of file AudioOutput.c.

#define AUDIO_NORMAL_SPEED_TRIGGER   (audio_buffer_size*3/8)

if audio buffer count is under this value, i2s will run in normal speed

Definition at line 56 of file AudioOutput.c.

#define AUDIO_SPEEP_UP_TRIGGER   (audio_buffer_size*5/8)

if audio buffer count is over this value, i2s will run in higher speed

Definition at line 54 of file AudioOutput.c.

Function Documentation

PRAGMA_ALIGN_4 uint8_t audio_buffer [2048*2] ATTR_ALIGNED

(

4

)

Definition at line 42 of file USBTask.c.

void Audio_DeInit

(

void

)

Definition at line 276 of file AudioOutput.c.

uint32_t Audio_Get_ISO_Buffer_Address

(

uint32_t

last_packet_size

)

Definition at line 207 of file AudioOutput.c.

void Audio_Init

(

uint32_t

samplefreq

)

Definition at line 221 of file AudioOutput.c.

void Audio_Reset_Data_Buffer

(

void

)

Definition at line 200 of file AudioOutput.c.

uint32_t CALLBACK_HAL_GetISOBufferAddress	(	const uint32_t	EPNum,
		uint32_t *	last_packet_size
	)

This callback function provides iso buffer address for HAL iso transfer processing.

Definition at line 325 of file AudioOutput.c.

void I2S0_IRQHandler

(

void

)

Definition at line 283 of file AudioOutput.c.

Status I2S_RateFind	(	LPC_I2S_T *	I2Sx,
		Chip_I2S_Audio_Format_T *	audio_format,
		I2S_RATE_CONFIG *	I2S_Config
	)

Definition at line 128 of file AudioOutput.c.

Variable Documentation

uint32_t audio_buffer_count = 0

Definition at line 70 of file AudioOutput.c.

uint32_t audio_buffer_rd_index = 0

Definition at line 68 of file AudioOutput.c.

uint32_t audio_buffer_size = 0

Definition at line 67 of file AudioOutput.c.

uint32_t audio_buffer_wr_index = 0

Definition at line 69 of file AudioOutput.c.

uint32_t CurrentAudioSampleFrequency = AUDIO_MAX_SAMPLE_FREQ

Current audio sampling frequency of the streaming audio endpoint.

Definition at line 58 of file AudioOutput.c.

uint32_t I2S_SpeedConfig_index

static

Definition at line 82 of file AudioOutput.c.

USB_ClassInfo_Audio_Device_t Speaker_Audio_Interface

Initial value:

= {
 .Config = {
  .StreamingInterfaceNumber = 1,

  .DataOUTEndpointNumber    = AUDIO_STREAM_EPNUM,
  .DataOUTEndpointSize      = AUDIO_STREAM_EPSIZE,
  .PortNumber = 0,
 },
}

LPCUSBlib Audio Class driver interface configuration and state information. This structure is passed to all Audio Class driver functions, so that multiple instances of the same class within a device can be differentiated from one another.

Definition at line 41 of file AudioOutput.c.