nRF5340 Audio DK: Walkie Talkie Demo - LINE IN instead of MIC

[fweinrebe]

Hello,

I am working with the Demo application for the Walkie Talkies using LE Audio. It works great with the onboard Microphone. I use only 2 boards. One is flashed as GATEWAY and the other is HEADSET (HS).

I now want to change the demo to get the audio input from the LINE IN socket instead of the Microphone.

What I tried I added the following to the prj.conf file as per recommendation from the SDK documents:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/applications/nrf5340_audio/README.html#enabling-the-walkie-talkie-demo

CONFIG_AUDIO_SOURCE_I2S=y

But the audio still comes from the Microphone instead of the LINE IN input.

How can I change the demo to work from the LINE IN input instead of the microphone?

Thanks

[fweinrebe]

Hi Amanda,

Many thanks your reply was very helpful.  Your post did not show up in my search because of the "_" in the name "WALKIE_TALKIE_DEMO".

I did change it now so that the Walkie Talkie config is removed from the proj.conf file and I added:

CONFIG_STREAM_BIDIRECTIONAL=y

This one was already there:

CONFIG_AUDIO_SOURCE_I2S=y

The Line In on the Gateway is working now but the Headset side is still on PDM Mic

 

In the Headset side of the code I found the problem, the compiler directives are still enabling the MIC.

In .../src/modules/hw_codec.c:

#if ((CONFIG_AUDIO_DEV == HEADSET) && CONFIG_STREAM_BIDIRECTIONAL)

    ret = cs47l63_comm_reg_conf_write(pdm_mic_enable_configure,

                      ARRAY_SIZE(pdm_mic_enable_configure));

    if (ret) {

        return ret;

    }

#endif /* ((CONFIG_AUDIO_DEV == HEADSET) && CONFIG_STREAM_BIDIRECTIONAL) */

After code was changed to this on the Headset section, the Line In worked on both sides:

#if ((CONFIG_AUDIO_DEV == HEADSET) && (CONFIG_AUDIO_SOURCE_I2S))

    if (IS_ENABLED(CONFIG_WALKIE_TALKIE_DEMO))

    {

        ret = cs47l63_comm_reg_conf_write(pdm_mic_enable_configure,

                                          ARRAY_SIZE(pdm_mic_enable_configure));

        if (ret)

        {

            return ret;

        }

    }

    else

    {

        ret = cs47l63_comm_reg_conf_write(line_in_enable, ARRAY_SIZE(line_in_enable));

        if (ret)

        {

            return ret;

        }

    }

#endif /* ((CONFIG_AUDIO_DEV == HEADSET) && CONFIG_STREAM_BIDIRECTIONAL) */

EDIT: Using NCS 2.2.0 but 2.3.0 was fixed already.

Regards

Fritz