Component: WAV Library File (Audio Output)

Author	Matrix TSL
Version	1.0
Category	Audio Output

WAV Library File component

Allows WAV files to be played or recorded using a file component to provide the data. Complete with buffer to allow for uninterrupted playback when performing other tasks. Playback compatible with analogue outputs such as DAC or PWM. Recording compatible with analogue inputs such as a Microphone.

Component Source Code

Please click here to download the component source project: FC_Comp_Source_WAV_Player_FAT.fcfx

Please click here to view the component source code (Beta): FC_Comp_Source_WAV_Player_FAT.fcfx

Detailed description

No detailed description exists yet for this component

Examples

No additional examples

Macro reference

StartPlayback

	StartPlayback
Start playing a WAV file from the SD card. Use the GetNextSample and EndOfFile macros to read out the contents of the file. Use the ProcessBuffer macro to maintain the local buffer. Returns 1 if file found and opened, else returns 0.
- STRING	Filename
WAV Filename e.g. "Test.wav"
- BYTE	Return

EndOfFile

	EndOfFile
A simple check to see if we are at the end of the file. Returns 0 if we and not yet at the end fo the file. Returns 1 if we are at the end of the file.
- BOOL	Return

ProcessBuffer

	ProcessBuffer
When Playing a WAV File - Fills the local data buffer from the SD card. When Recording a WAV File - Writes the local data buffer to the SD card. Must be called often enough to maintain playback or recording. Returns 0 for buffer OK 1 for buffer overrun
- BYTE	Return

StopRecording

	StopRecording
- VOID	Return

PutNextSample

	PutNextSample
Writes the value for the next sample and auto increments the file pointer. Ideally this function should be called as part of a timer interrupt at the sample rate. The value written should be collected using an analogue input such as a Mic.
- UINT	Sample
- VOID	Return

GetNumChannels

	GetNumChannels
Returns the number of audio channels stored in the WAV file during playback.
- BYTE	Return

StartRecording

	StartRecording
Start recording a WAV file to the SD card. Use the WritetNextSample macro to write the contents of the file. Use the ProcessBuffer macro to maintain the local buffer. Returns 1 if file created and opened, else returns 0.
- STRING	Filename
WAV Filename e.g. "Test.wav"
- BYTE	BitsPerSample
Number of bits per sample - 8 or 16
- ULONG	SampleRate
Sample Rate in Hz e.g. 8000 for 8KHz
- BYTE	Return

GetBitsPerSample

	GetBitsPerSample
Returns the number of bits per sample during playback.
- BYTE	Return

GetNextSample

	GetNextSample
Retreives the value for the next sample and auto increments the file pointer. Ideally this function should be called as part of a timer interrupt at the sample rate. The value returned should be passed onto a means of analogue output e.g. a DAC or PWM.
- UINT	Return

Property reference

	Properties
	LinkTo
	Buffer Size
The number of RAM bytes to allocate to the WAV buffer. The buffer must be big enough to store enough WAV audio samples to maintain playback or recording when doing other program tasks or performing SD card read/write operations.
	Memory Type