nRF5340 PDM Mic data send over BLE to PC/mobile to process the audio file

[Virat]

Hi nRF Team,

I would like to know more detailed operation of LE audio profile on nRF5340.

My requirement is to continuously process PDM mic ( PCM data ) interfaced to nRF and send that PCM data over BLE to PC/Mobile(any app is available) to process further for audio. I dont need any audio board other side to process the data because only PC/mobile is allowed.

As of now, I have nRF5340 dk board and interfaced PDM mic, please see following log for confirmation.

PDM_outputdata_280624.txt 

After some exploration I came to know that there is a nRF5340 audio dk board. I have gone through the device datasheet, it is mentioned in BLE specs that it has a version of 5.3 with LE audio profile where as simple dk board doesnot have LE audio. How these two boards are different each other? Can I use nRF5340 dk board to proceed for my required development or shall I purchase nRF audio dk board.

Is any of these boards can fullfil my requirement?

Thanks in advance.

Regards,

Argus

[dejans]

Hi,

Both boards contain nrf5340 SoC which has I2S compatible, digital microphone PDM interface. In comparison to nrf5340-dk, nrf5340_audio-dk has been specifically designed for demonstrating the capabilities of nrf5340_audio applications. It is recommended platform for developing of LE Audio products.

Best regards,
Dejan

[Virat]

As we  shared LOG information about PDM data is correct ?

Could you please verify the file(PDM_outputdata_280624.txt).

 

Regards,

Argus.

[dejans]

Hi Argus,

Could you provide more information about your board and your application?

Virat said:

As we  shared LOG information about PDM data is correct ?

Could you please verify the file(PDM_outputdata_280624.txt).

Where did you take your log from?
Could you specify what kind of file verification you are interested in?

Best regards,
Dejan

[Virat]

Board Detals: nRF5340-DK

Version:SDK v2.6.0

MIC Details:IMP34DT05

MIC is interfacing with PDM. Getting the below data. How to verify weather data is correct are not.
(I am using sample code)

f85f f898 f8dc f8e2 f8f4 f905 f8fa f903 f917 f91d f946 f976 f990 f9aa f9be f9dc fa0a fa37 fa6c fa7e fa9e fac1 fad7 fadd fae1 faf1 faf0 fae5 fadd  

Regards,

Argus.

[dejans]

Hi Argus,

dejans said:

Where did you take your log from?
Could you specify what kind of file verification you are interested in?

Could you provide this information?

Could you also provide more information about your application? What is your application doing and what do you expect to happen?

Virat said:

(I am using sample code)

Which sample code do you use?

Best regards,
Dejan

[Virat]

Hi Dejans,

I am taking the sample code is Dmic sample in that do_PDM_transfer function is there,In this function I added below logic. 

uint16_t *data_ptr = (int *)buffer;
        for(int j = 0; j < size/2; j++){
            printk("%x ", *data_ptr);
            data_ptr++;
        }

This data can convert to .wave or any other audio format file? 

[dejans]

Hi,

It is possible to convert PCM data to WAV.
You can read about the similar issue - extracting data using dmic.

Best regards,
Dejan