nrf5340 Audio Application - I2S Slave

RE: nrf5340 Audio Application - I2S Slave

Karl Ylvisaker — Mon, 06 Nov 2023 15:16:52 GMT

Hello Gregor,

Thank you for clarifying - I understand your use-case and I see how it would be beneficial to have this as an easily configurable option in the reference application. I will also discuss this possibility with the LE Audio team to potentially create a task for them to create this in the future, but if this were to happen it would be some time into the future.

Unfortunately, there is no supported non-application-breaking way to do this, and so you would indeed have to follow the approach outlined in the two tickets referenced by your colleague here.

Best regards,
Karl

RE: nrf5340 Audio Application - I2S Slave

G-bauer — Mon, 06 Nov 2023 11:56:45 GMT

Hello,

as my colleague is not returning until Wednesday I will reply instead. The reason why we would like to configure the nRF5340 as slave is because we have a 'main' DSP device that ought to receive audio from various different sources. One of these sources is the I2S interface of the nRF5340, which we use to forward and return audio from and to BLE. Since we have various different audio sources that we need to synchronize on our main device, it seems reasonable to us to configure our main device as master in terms of I2S rather than the nRF5340. Is there any supported non-application-breaking way of achieving this? Or will we have to use a workaround like it is described in the posts liked by my colleague?

Thank you in advance!
Kind regards,

Gregor

RE: nrf5340 Audio Application - I2S Slave

Karl Ylvisaker — Mon, 30 Oct 2023 13:42:04 GMT

Hello Martin,

Thank you for your patience with this.

[quote user=""]I have followed the instructions Amanda has given (diabling drift_comp and pres_comp here), but with no luck.[/quote]

Could you elaborate on the issue you are seeing when doing this? How does it fail, and how does it behave compared to what you would have expected? Could you share the changes/modifications you made?

[quote user=""]

The issue Max was having is now 5 months old, maybe there have been some updates from your side. I am using NCS version 2.4.2.

Could you elaborate, why the compensation mechanisms have to be avoided in this configuration? Why does disabling I2S clock output for the gateway break the application?

[/quote]

The nRF5340 Audio application is built on some assumption about the synchronization between the NET and APP core (and more explicitly also between the I2S peripheral and the NET core), and so when these assumptions no longer holds then the application will break. I guess it comes down to that since this is not a supported feature of the nRF5340 LE Audio reference application it is not something that the LE Audio team is working to ensure is possible, or have made any tests or accommodations for.

Could you elaborate on your use-case here, so that I may understand your situation better?

Best regards,
Karl