Confusion about the A2DP-HFP pipeline example

[RaresCon]

In the A2DP-HFP pipeline example, I am not sure I understand how the HFP client-pipeline interaction works. The `pipeline_e` variable represents a pipeline that reads data from the codec ES8388 (I assume from the mics that are attached to LyraT for example and connected to the L/R IN lines) and then sends it through the HFP client to the phone/whatever BT device is connected to the board. Is this correct or the example does not transmit any voice data back to the device that received the call?

And if this is correct, what configuration must be done for the codec ES8388 to send that data over I2S to the ESP and not use it during output mixing (as seen in the ES8388 datasheet, where the L/R IN lines seem to be used during mixing of the output)?

Thanks for responding!

[hamzatamer76]

Hi, did you solve the problem? I am also developing with Lyrat Mini, but in the example you gave, the A2DP part works without any problems, while the HFP part does not work. The microphone does not detect or transmit sounds during a call.

[RaresCon]

Hi! I have not resolved the issue, because I use an ESP32-WROOM-32D and an ES8388 codec breakout board. I haven't connected a microphone to the ES8388 to test, but I get another problem on the A2DP sink example. The I2C commands do not work after starting the I2S stream, meaning that all I2C commands to the codec return a HW NACK, which is really strange, because before starting the I2S stream, the calls work just fine. Do you know anything specific about LyraT that I should keep in mind?