Get sound data on gateway NRF5340 audio DK

[flamefire]

We are doing some module testing, and we want to get the audio data on the gateway, before it is sent over bluetooth.
Right now we send data through gateway, and collect again on headset.
Specifically we are testing different filters applied to an audio signal. We have tried to send the data to the consol
but it seems there is restrictions on speed, so its not all the data that is fed through.

Can i save the data in a file, and collect on the pc?

[flamefire]

For information we are using two nrf5340 audio DK boards, to send audio from gateway to headset using this application: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/applications/nrf5340_audio/README.html

In the function:

int sw_codec_decode(uint8_t const *const encoded_data, size_t encoded_size, bool bad_frame,

            void **decoded_data, size_t *decoded_size)

We are processing the pcm data before LC3 encoding with:

sw_codec_lc3_enc_run(pcm_data_mono[AUDIO_CH_L], pcm_block_size_mono,

                           LC3_USE_BITRATE_FROM_INIT, AUDIO_CH_L,

                           sizeof(m_encoded_data), m_encoded_data,

                           &encoded_bytes_written);

We want to get the data out before LC3 encoding.

[Amanda Hsieh]

Hi, 

https://github.com/nrfconnect/sdk-nrf/blob/main/applications/nrf5340_audio/src/audio/sw_codec_select.c#L64. The char pcm_data_mono is just pure PCM data.

https://github.com/nrfconnect/sdk-nrf/blob/8d552d2f049c096a6c7188299d39c5b4afe1b64e/applications/nrf5340_audio/src/audio/audio_system.c#L146 pcm_raw_data is PCM data as well, but it's both left and right and the bit depth is 16 bits, so every two bytes it will alternate between the two channels.

Regards,
Amanda H.

[flamefire]

Thank you for response! Yes we are aware of that, we have also converted the pcm data to int16 for both channels and back.

What i meant by getting the data "out" is to write the data to a file that can be accessed on the computer. Or if there is pin on the Audio DK board that we can send signal out. We have tried uart but its restricted in messages to console.

[Amanda Hsieh]

Hi, 

I think you can write data to SD Card. All the functionality you need to get this up and running is present in the sd_card.c/h files. 

I will be out of the office until next Tuesday. If you are urgent to get a reply to further questions, please create a new support case. 

Regards,
Amanda H.