I2S Echo Sample
This sample demonstrates how to use an I2S driver in a simple processing of an audio stream. It configures and starts both the RX and TX streams and then mixes the original signal with its delayed form that is buffered, providing a simple echo effect.
The sample uses the WM8731 audio CODEC that can be found, for example,
on the Audio Codec Shield, but it can be easily adapted to use other
CODECs. The I2S device to be used by the sample is specified by defining
a devicetree node label named
i2s_rxtx or separate node labels
i2s_tx if separate I2S devices are to be used for the RX and TX
This sample has been tested on nRF52840 DK (nrf52840dk_nrf52840) and nRF5340 DK (nrf5340dk_nrf5340_cpuapp), using the Audio Codec Shield, and provides overlay files for both of these boards.
More information about the used shield and the CODEC itself can be found here:
Building and Running
The code can be found in samples/drivers/i2s/echo.
To build and flash the application:
west build -b nrf52840dk_nrf52840 samples/drivers/i2s/echo west flash
Press Button 1 to toggle the echo effect and Button 2 to stop the streams.