Minimal TWS sink sample for nRF5340

[Zipdox]

I want to design a pair of TWS speakers using the nRF5340, but I'm having a hard time figuring out where to start. From what I understand, the unicast server nRF5340 audio application is the closest thing to what I'm looking for. The only problem is that I do not have two nRF5340 Audio DKs. I have more barebones development boards from a third party (E83-2G4M03S-TB). Is there a more minimal example that just outputs I2S and nothing else? Alternatively, how could I configure the unicast server application to remove everything except I2S output?

[Syed Maysum Abbas Zaidi]

Hi,

You are correct that the nRF5340 Audio unicast server application is the closest match to what you want. It already implements the LE Audio sink role and outputs decoded audio over I2S, and it can be configured for left/right stereo operation for TWS style use. However at the moment, Nordic does not provide a separate “minimal” LE Audio TWS sink example that only does I2S output, and there is no documented way to easily strip the unicast server down to just I2S while keeping all LE Audio functionality. The audio applications are intentionally fairly large, as they integrate LE Audio, LC3 decoding, synchronization, and audio routing.

For third-party nRF5340 boards, the usual approach is:

1. First bring up I2S and your external codec using a simple I2S playback example to verify pins and clocks on your hardware.
2. Then use the nRF5340 Audio unicast server (or broadcast sink) as a reference and adapt it to your board, disabling non-essential features as needed.

So the supported path is to start from the existing audio applications and port them to your hardware.

Best Regards,
Syed Maysum

[Zipdox]

So I assume I have to create a new board in nRF connect first? I suppose I could take Audio DK board as a reference and remove everything I don't need and take note of what is removed to remove it in the audio application code as well?

[Syed Maysum Abbas Zaidi]

Hi,

Yes, since you’re using a third-party nRF5340 module, you’ll need to ensure that NCS has a board definition that matches your hardware. For the nRF5340 Audio applications, this typically means creating a custom board and adapting an existing reference board (such as the nRF5340 Audio DK) by editing devicetree and Kconfig to reflect your pin mapping and available peripherals. You can refer to the documentation on adding a new board for guidance on this process.

Rather than removing large parts of the application source code, the recommended approach is to minimize features via configuration (devicetree and Kconfig). This keeps the audio application structure intact while adapting it cleanly to your hardware.

Best Regards,
Syed Maysum