I2S

Not to be confused with I2C, is a protocol for connecting to audio devices. The samples are sent continuously in the background using DMA transfer.

This library is in beta, and the API / implementation is subject to change!

To use this library, include it in your code:

#include "I2S.h"

I2SClass i2s(...);

I2SClass(SPI_TypeDef *instance);

Construct I2S that will be connected to the specified I2S instance on chip.

The board default pins will be used for sd/ws/ck. mck will not be used.

I2SClass(SPI_TypeDef *instance, uint8_t sd, uint8_t ws, uint8_t ck);

Construct I2S that will be connected to the specified I2S instance on chip.

The specified pins will be used for sd/ws/ck. mck will not be used.

I2SClass(SPI_TypeDef *instance, uint8_t sd, uint8_t ws, uint8_t ck, uint8_t mck);

Construct I2S that will be connected to the specified I2S instance on chip.

The specified pins will be used for sd/ws/ck/mck.

uint8_t I2SClass::begin(i2s_mode_t mode, uint32_t sampleRate, uint8_t bitsPerSample);

Configure the pins, and the parameters for the connection.

write(int16_t data);

Send 16 bit data. Blocks if there is no space left in the internal buffer.

write(int16_t *data, uint16_t size);

Send 16 bit data. Blocks if there is no space left in the internal buffer.

setBuffer(uint16_t *buffer, int bufferSize);

Set the DMA transfer buffer size. The default buffer is 2048 * 16 bits.

int getBufferSize();

Returns size of the transfer buffer.

stm32SetSD(uint8_t pin);

Set the alternative SD pin used by this I2S.

This method must be called before begin()!

stm32SetWD(uint8_t pin);

Set the alternative WD pin used by this I2S.

This method must be called before begin()!

stm32SetCK(uint8_t pin);

Set the alternative CK pin used by this I2S.

This method must be called before begin()!

stm32SetMCK(uint8_t pin);

Set the alternative MCK pin used by this I2S.

This method must be called before begin()!