Pmod i2s2 with an ESP32

[Nathan Byrer]

I would like to use the Pmod i2s2 with an ESP32.  Does anyone have experience wiring these up together and be willing to point me to documentation, help guide, or other resource?  

Thank you in advance.

[artvvb]

Hi Nathan,

Digilent doesn't have any materials on using the two Pmods together, other than what you might have found already for using each of them with various different dev kits individually (here are some links for resource centers with documentation for the Pmod ESP32 and the Pmod I2S2). How to proceed really depends on what you're trying to do with them. Couple examples: you might be able to stream audio data from a computer, might be able to play different locally-stored sounds based on commands sent over WiFi, or might be able to configure I2S clock settings or some audio DSP parameters in an audio processing chain through WiFi access. It really depends.

Thanks,

Arthur

[Nathan Byrer]

@artvvb, thanks for the response.  I'm planning on using the Pmod i2s2 with an ESP32 running WLED Sound Reactive.  I'd like to plug a microphone into the input of the i2s2.  

[artvvb]

Sounds like a cool project, I haven't run across WLED before. It looks like it might be nontrivial to set up, looking through some initial documentation for WLED, it looks like it (at least by default) uses the GPIO36/Sensor_VP pin of the ESP32 for audio input, which isn't wired to any I/O on the Pmod ESP32. Maybe rewrites of the WLED code to accept data from the UART line would be possible, but I'd expect it to substantially drop the achievable data rates.

Couple of sources:

• https://github.com/atuline/WLED/wiki: Default pins used section
• https://digilent.com/reference/_media/pmod/pmodesp32/pmodesp32_sch.pdf: Sensor_VP is N/C
• https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf: pin definitions on page 9

One other thing to note is that microphones can require some additional setup over line out audio from a PC: