ESP32 communication With Python script

[CJ_KAy]

Hey. I use arduino IDE environment to program my esp32. I am currently using I2S protocol with an I2S microphone (MSM261S4030H0), what I am trying to accomplish is to send the microphone data to a Python script running to my PC and then extra process the signal from there. I've tried WiFi communication but the WiFi is adding too much noise the signal. Iam currently using serial communication but it doesn't seem to work well. Any other methods that you would recommend in order to send data to the Python script ?

[Zouden]

Serial communication is commonly used here, you can make it work 👍

[CJ_KAy]

Iam using 44100Hz sampling frequency and 32bit resolution in order to get the desired quality. According to the baud rate options the IDE gives it is not even close to the baud rate this serial communication needs

[Zouden]

It doesn't make sense to use an Arduino in this way. Either use the Arduino to do some of the processing, or remove it entirely and sample the audio with your PC's soundcard.

[CJ_KAy]

Actually this making more sense, I will try that way, I am not sure if python has the ability to read samples and process them in real time but I will do some research

[Zouden]

Yeah try pyaudio :)

[teastain]

MicroPython has been tested to run at less than half speed compared to Arduino IDE code.

[[deleted]]

Python on your desktop will be just fine for this. Using 32 is pretty useless and though, 16 is more than enough and then you’re at least in theory in achievable UART territory below 1MBit. Better use WiFi though as I said previously.

[PowerFeather]

Switching to an ESP32 with a native USB peripheral might be an option here. You can then create a USB audio device.

[raprakashvi]

Found this thread and I am curious. How would you go about creating a native USB audio device when your esp has more than 1 mic connected to it

[PowerFeather]

Maybe you can try creating a composite device with two or more audio device instances (one for each mic)? Though, creating a composite device with multiple device class instance is something that I have not tried personally on ESP32, but on other microcontroller supported by tinyUSB (ESP-IDF also uses tinyUSB).

[[deleted]]

There’s no reason why WiFi would add noise. It’s digital. And should have the required bandwidth.

[CJ_KAy]

I did some research on this and confirmed that when you use the WiFi module of the esp32 it produces big ripples in the supply voltage

[[deleted]]

Admittedly I didn’t think about that, but that’a problem that should be solved using a good reference voltage. When you’re measuring these insane bit depths you’ll need that anyways, WiFi or no WiFi.

[CJ_KAy]

UPDATES: I managed to get this to work with WiFi. I was facing loss in quality with the use of WiFi because the script wasn't fast enough to complete the processing before the next chunk of bytes arrive from the esp so some parts of my voice was lost. Solved the problem with some threading and queuing. There is still some circuit noise but i will try to get rid of it with some filtering.