from i2s audio to ble streaming

RE: from i2s audio to ble streaming

chaabani — Fri, 31 Aug 2018 12:32:17 GMT

Hi
no you don't need to change, it the same clock frequency of the microphone used in that exemple.

best regards
Houssem

RE: from i2s audio to ble streaming

Kong_Scott — Fri, 31 Aug 2018 02:44:27 GMT

I finally solve that C file problem. I didn't know app_pwm.c was included in the example file.

But next problem is Clock frequency.

I saw on datasheet shp0645 support 2048MHz~4096MHz (BCLK). Then do I have to change

BCLK,LRCK CLOCK ?

Did you change it?

Thank you

SCOTT

RE: from i2s audio to ble streaming

chaabani — Thu, 30 Aug 2018 16:56:26 GMT

Hi Scott

i tested the microphone with sdk13 and sdk14 and it is working fine in the two cases.
maybe you forgot to change the app_pwm.c as noted in the github link.

kind regards
Houssem

RE: from i2s audio to ble streaming

Kong_Scott — Thu, 30 Aug 2018 01:43:25 GMT

Thank you for your help.It is very useful.

But I'm confused somehow.

Which version of SDK did you use ? I'm using SDK 15.0.

Especially, function

err_code = app_pwm_ticks_init(&PWM1,&pwm1_cfg,pwm_ready_callback);

is not working.

Can you please let me know, Which C file include that function ?

I'm using perfectly same sensor with you.

Thanks again.

Scott

RE: from i2s audio to ble streaming

chaabani — Tue, 28 Aug 2018 13:27:52 GMT

Hi Kong_scott

the problem is that the nrf52 support only 24 bits and this microphone works with 32 bits.
So we need to change the clk of the i2s of the microphone. here is the solution that i found on github https://github.com/gregtomasch/nRF52_24-bit-_I2S_Microphone_Audio_Recording_Utility

best regards
houssem

RE: from i2s audio to ble streaming

Kong_Scott — Tue, 28 Aug 2018 11:41:08 GMT

Hi hch!

I'm very happy to find someone that success using sph0645. Actually I am confused using that microphone.

I connected

BCLK - SCLK

DATA OUT - SDIN

WS - LRCK

just like this.

But the data only I can get is

<info> app: 1: 0000/0000, expected: CAFD/CAFF (i: 2).

What should I change? I'm using SDK15, i2s example.

Please let me know.

Best regard.

Scott

RE: from i2s audio to ble streaming

Håkon Alseth — Thu, 09 Aug 2018 14:02:01 GMT

Hi,

The problem is that you do not have any native support on the phone / PC for handling the audio.

There are some (limited) options for audio streaming over BLE, see for instance https://devzone.nordicsemi.com/question/72254/is-any-ble-chipset-supports-audio-streaming/. It is technically possible to stream audio via BLE, but there are currently no standardized profiles for it. The Thingy:52 demonstrates that it can be done, and you can also find products in the marked that uses audio over BLE - typically remote controls with voice input. You can take a look at the smart remote 3 which demonstrates transmission of speech. This uses the Opus codec for audio compression (or ADPCM for the older implementation).

Best regards,

Håkon

RE: from i2s audio to ble streaming

chaabani — Thu, 09 Aug 2018 13:35:24 GMT

Hi,

I saw the demo of image transfer and it's was a very good exemple.
if it's possible to stream image with big size data why it's not possible to stream audio ?

Best regrads,

Houssem

RE: from i2s audio to ble streaming

Håkon Alseth — Thu, 09 Aug 2018 13:18:38 GMT

Hi,

Bluetooth LE is not made for streaming audio, and there is no official bluetooth low energy audio profile available.

Sounds like you want to use Bluetooth Classic, which we do not offer in our radios.

Kind regards,

Håkon