#ESP32 I2S MEMS Microphone Arduino IDE Example This repository holds some samples for connecting a I2S MEMS microphone to an ESP32 board.
At first I thought hooking up an I2S microphone would be straight forward, but it seems that I2S is a somewhat new or neglected interface. The examples distributed by adafruit only apply for Feather M0; the generic I2S example from the ESP32 examples is not directly applicable. Hence this repository.
I am using these components:
There are no dedicated I2S pins on the ESP32. Instead, you will have to configure/enable the pins in your code. Eventually, I connected I2S-MEMS pins to the following ESP32 pins:
- SEL is unconnected, i.e. only one channel, apparently left
- LRCL to #15
- DOUT to #32
- BCKL to #14
- GND to GND
- 3V to 3V
Don't try to connect them to the similar sounding SCL/SCA/SCK, they're for the incompatible I2C interface.
You can open each of the examples as a sketch in the Arduino IDE. I've commonly used a baudrate of 115200, you will need to configure this in your serial monitor, otherwise it'll display rubbish.
- Either the
SELconfig is wrong, or the ESP32 I2S channel handling.- I had to use
I2S_CHANNEL_FMT_ONLY_RIGHTwheneverSELpin was unconnected/ground, andI2S_CHANNEL_FMT_ONLY_RIGHTwhenSELis high.
- I had to use
- I could only get it to work with 32 bit sampling.
- I don't know if this is a limitation of either hardware, or a configuration mistake on my side.
- Although the setup seems to react nicely to noise.
- I do not know if the recorded data is actually a valid sound.
- There might be some bit-juggling still to be done.
Credits go to Adafruit for the easy-to-use hardware and the nice guide (even if it is not fully applicable here, it's still a great place for starters) and the espressif examples.