Can we use I2S and USB both for audio out?

[Puneeth1]

Hi 

we need to connect nrf audio to two different module( 1 LTE, 2 PI ), so we are planning to use USB audio to PI (Linux) module and I2s audio to Lte module.

our question is does NRF5340 can use as a bridge in following cases.

case 1. 

- nrf should receive audio from LTE module the same data need to transfer to Pi module, and vice versa.

Case 2

- nrf should receive audio from LTE module the same data need to transfer by BLE, an vice versa.

Case 3.

- nrf should receive audio from Pi module the same data need to transfer by BLE, an vice versa.

Thanks 

Puneeth

[Kenneth]

Hello,

I think your main problem will be if you are able to control which of the audio interface is a (audio) master and (audio) slave at any given time. Only one of the interfaces can be a (audio) master at any given time, the other interace must be a (audio) slave, else you will experience clock drift between the interfaces which will cause audio overrun or audio underrun in the buffers, and you will not have resources to compensate for this in the nRF5340, so it will cause audio glitches if you have two (audio) masters at the same time.

Kenneth

[Puneeth1]

Hi Kenneth 

Thanks for your response!!

If nRF support 1 Host and 1 slave means we can use in the following way

1. IK nRF USB audio act as slave so we can connector our Linux module it will be a master.

2. out LTE module i2s can be used as slave only so, nRF i2s can be used as a master.

does this configuration will work?

Puneeth

[Kenneth]

Hello,

I do believe this will work yes. I can't think of any reason this should not work then.

Kenneth

[Puneeth1]

Hi 

Thanks for the Good news!!

do you have any example SDK for this or for using USB audio and I2S audio. this would be very helpful.

Puneeth

[Kenneth]

Hello,

In general you can find examples two places:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/index.html 
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples.html 

I have not looked through all examples, but I could find these that may be useful:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/boards/litex/i2s/README.html 
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/subsys/usb/audio/headphones_microphone/README.html 
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/subsys/usb/audio/headset/README.html 

Kenneth

[Puneeth1]

Thanks! Kenneth