I have never dealt with digital audio interface like I2S.

I want to use ESP-07S / ESP8266 audio interfaces as digital audio I/O (for mic + speaker). ESP-07 has two I2S interfaces: 3-wire audio input interface and 3-wire audio output interface.

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ESP-07 manual: https://www.rfsolutions.co.uk/downloads/1494602250ESP-07S_Datasheet.pdf

I found the IC WM8974 of Cirrus Logic a bit interesting. Here is the recommended schematic/interface shown at the last pages of its datasheet:

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Datasheet of WM8974: https://d3uzseaevmutz1.cloudfront.net/pubs/proDatasheet/WM8974_v4.7.pdf

The names of the signals of them are different. For example, there is no "MCLK" signal on ESP-07. I wonder if it is possible to interface that audio IC with the ESP-07... If yes, how do I need to interconnect the parts?

If not, which kind of IC should I use to interface to that ESP-07 I2S interface? This audio IC is called "audio coded mono", so for what keywords should I search.

This is shown on the ESP-07 manual about its I2S:

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  • \$\begingroup\$ As you can see, the WM codec needs a master clock to operate. However the WS and BCK can be inputs or outputs, so it can be a clock master and generate I2S clocks from the MCLK. If the ESP can be set to clock slave so WS and BCK are inputs, it can work. \$\endgroup\$ – Justme Jun 12 '20 at 12:16

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