nRF5340 audio dk stereo issue with cis bidirectional mode

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

Karl Ylvisaker — Thu, 17 Aug 2023 13:02:56 GMT

No problem at all, I am happy to help! :)

Please do not hesitate to ask if you should have any follow-up questions later on.

Best regards,
Karl

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

slswks — Sat, 12 Aug 2023 03:43:15 GMT

Okay, thanks Karl. We'll do as you suggest.

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

Karl Ylvisaker — Thu, 10 Aug 2023 12:51:11 GMT

Hello again,

[quote user="slswks"]Thanks for the quick response[/quote]

No problem at all, I am happy to help! :)

[quote user="slswks"]Oh, and another question, can I switch to just the right channel without hardware mods?[/quote]

No, unfortunately not - the CS47L63 will only output on the 'left' connector on the audio jack.
You could of course change the payload of the channel to be the 'right' data stream, but it would still come out in your left ear on the headphones connected to the jack.

[quote user="slswks"]Do you have any suggestions for what codec chip to use?[/quote]

We do not have any official recommendation for this, unfortunately, but I suppose most external/'breakout board' stereo channel codecs should work, so long as they can accept the I2S output from the nRF5340.

Best regards,
Karl

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

slswks — Thu, 10 Aug 2023 08:06:20 GMT

Oh, and another question, can I switch to just the right channel without hardware mods?

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

slswks — Thu, 10 Aug 2023 07:54:25 GMT

Thanks for the quick response! That's great information. Do you have any suggestions for what codec chip to use?

RE: nRF5340 audio dk stereo issue with cis bidirectional mode

Karl Ylvisaker — Thu, 10 Aug 2023 07:16:44 GMT

Hello,

[quote user=""]

In this configuration, I'm connecting to a set of ear buds but only the left channel is present on the dk headphone jack from the ear bud microphones.

Is this a limitation of the dk hardware, app or do I have something misconfigured?

[/quote]

No worries, you have not misconfigured anything; The nRF5340 Audio DK's onboard CS47L63 chip functions as a DAC to output the audio to the audio jack - however, this DAC only processes a single audio channel, and so the LE Audio DK will only output 1 channel (the left) on the audio jack.

In essence, there is no technical limitation on the nRF5340 to be able to output stereo audio.
If you would like to output stereo audio you will need to use an external stereo DAC. In that case, you can bypass the onboard Cirrus Logic chip by doing the following:

Best regards,
Karl